Researchers Transform Sewage Sludge Into Power

by Ariel Schwartz

Waste treatment plants have to get rid of sludge somehow, so why not try to find a way to turn all that muck into energy? That’s what researchers at the University of Nevada, Reno are attempting to do at the Truckee Meadows Water Reclamation Facility. If all goes well in Truckee, the system could be expanded to other reclamation facilities in the state. And with 700,000 metric tons of dried sludge generated each year in California alone, there’s a huge opportunity to generate low-cost, low-impact energy for widespread use.

The gasification process developed by the researchers sticks the sludge in a low-temperature bed of sand and salts, as waste heat from the facility drives the dryer’s electricity and the unsavory mix dries out into a powdered biomass fuel and . So far, researchers have been able to produce three pounds dried powder from 20 pounds sludge each hour. Eventually, they hope to develop a full-scale system that could generate 25,000 kilowatt-hours per day–enough to completely power the reclamation facility.

World’s First Molten Salt Solar Plant Produces Power at Night

by Philip Proefrock

Sicily has just announced the opening of the world’s first concentrated solar power (CSP) facility that uses molten salt as a heat collection medium. Since molten salt is able to reach very high temperatures (over 1000 degrees Fahrenheit) and can hold more heat than the synthetic oil used in other CSP plants, the plant is able to continue to produce electricity even after the sun has gone down.

While photovoltaic solar panels work by directly producing electricity from sunlight, CSP plants use mirrors to concentrate sunlight and produce high temperatures in order to drive a turbine to generate electricity. CSP plants have been in existence for many years, but the Archimede plant is the first instance of a facility that uses molten salt as the collection medium.
Heat from the molten salt is used to boil water and drive the turbines, just like other fossil fuel plants. CSP plants use the same kind of steam turbines as typical fossil fueled power plants. This makes it possible to supplement existing power plants with CSP or even to retrofit plants to change over to clean energy producing technology. Some existing CSP plants have used molten salt storage in order to extend their operation, but the collectors have relied on oil as the heat collection medium. This has necessitated two heat transfer systems (one for oil-to-molten-salt, and the other for molten-salt-to-steam) which increases the complexity and decreases the efficiency of the system. The salts used in the system are also environmentally benign, unlike the synthetic oils used in other CSP systems.

Since molten salts solidify at around 425 degrees F, the system needs to maintain sufficient heat to keep from seizing up during periods of reduced sunlight. The receiver tubes in the Archimede facility are designed to maximize energy collection and minimize emissions with a vacuum casing that enables the system to work at very high temperatures required with molten salts. By using the higher temperatures of molten salts, instead of oil, which has been used in other CSP plants until this point, the plant is able to maintain capacity well after the sun sets, allowing it to continue generating power through the night.
The Archimede plant has a capacity of 5 megawatts with a field of 30,000 square meters of mirrors and more than 3 miles of heat collecting piping for the molten salt. The cost for this initial plant was around 60 million Euros.

Ultra-Efficient Bladeless Wind Turbine Inspired by Nikolai Tesla

by Philip Proefrock

SolarAero recently unveiled a new bladeless wind turbine that offers several advantages over current wind turbines — it emits hardly any noise in operation, has few moving parts, and since it doesn’t use spinning blades it’s much less of a hazard to bats and birds. The whole assembly is inside an enclosed housing, with screened inlets and outlets to keep animals safely out. It also can be installed on sensitive locations such as radar installations or sites under surveillance where the rotating blades cause detrimental effects. Read on to learn what makes it work.

 

 

 

Whether they are vertical axis or horizontal axis, typical wind turbines work by catching moving air with blades, and using that force to rotate the axle, which turns a generator to produce electricity. Instead of pushing on blades, SolarAero’s turbine is based on the Tesla turbine originally developed by Nikolai Tesla. The principle of the Tesla turbine is to set up an array of closely-spaced, very thin, and extremely smooth metal disks. The viscous flow of air moving in parallel to the disks is what propels the turbine, instead of buffeting blades with moving air. This makes for a more compact mechanism with only one moving part: the turbine-driveshaft assembly.
According to the company, this turbine should cost around $1.50 per watt of rated output, and have a lifetime operating cost of about 12 cents per kilowatt-hour — comparable to, or even better than, current retail electrical rates in many parts of the country. This would make the SolarAero turbine about 2/3 the price of a comparable bladed unit, and because of the significantly lower operating costs, lifetime maintenance could be just 1/4 the cost. At this point the project is still under development, and no manufacturer has been lined up as of yet.

Turbine Light Illuminates Highways With Wind

by Ariel Schwartz

As more and more people across the world adopt cars as their primary mode of transportation, well-lit highways become increasingly important. But how can we sustainably power all those energy-sucking lights? TAK Studio addressed that question in their entry into this year’s Greener Gadgets competition to find the green technology solution of the future. Dubbed the Turbine Light, their design aims to illuminate our roadways using the power of the wind.

TAK’s wind-powered light uses the moving air from cars zipping by on the highway to generate energy that can be used to power roadside lighting. It’s a controversial idea–could wind from passing cars actually provide enough power for lighting?–but one that has the potential to save lots of cash in already wind-heavy regions. Alternatively, cities might consider using solar-powered lights instead. The idea has been proven to work many times over, including at the recent COP15 climate change conference.

Bercy Chen Buries a High-Tech Update of a Traditional Pit-House

by Lloyd Alter

Bercy-Chen Studio is doing a fascinating 1400 square foot residence in Austin, Texas that hits all the right TreeHugger buttons. It is on a modern version of the pit-house used by ancient Pueblo and Cherokee Indians.
The Red Bluff house is a little more sophisticated; like the pit-house it uses the earth's thermal mass to temper the climate. However it adds a few modern touches like hydronic heating & cooling, geothermal heat exchange, phase-change thermal heat storage, rainwater collection and a green roof.

The architect writes:

The house's relationship to the landscape both in terms of approach as well as building performance references the oldest housing typology in North America; the pit house. Like a pit house, the house will undergo a 7-foot excavation gaining benefits from the earth's mass to maintain thermal comfort throughout the year. Such architectural settings create opportunities for maximum energy efficiency using a proposed Integrated Hydronic HVAC system.

The heating and cooling system is very sophisticated, yet based on simple principles of thermal mass and time-shifting. Heat from the sun is absorbed through the patio floor and circulated into phase change storage, smoothing down the peaks and reducing load on the heat pumps. (See full size drawing on flickr here)

According to Designboom, the site is a brownfield that contained an oil pipeline that will be excavated and removed, and that "central to this retreat for a science fiction writer is the healing of the land, a charges site where the urban/industrial condition once met nature in a brutal and unsympathetic manner."

Sanyo Unveils World’s Most Efficient Solar Module HIT-N230

by Yuka Yoneda

Electronics giant Sanyo recently announced the development of what they are claiming is the world’s most efficient solar module. Called the HIT-N230, the new module has an impressive energy conversion efficiency of 20.7% which is unprecedented in the market.

How did Sanyo achieve this feat? According to Akihabara News’ report, the leader in solar module manufacturing increased the number of solar cell tabs from 2 to 3 and made each tab thinner. They also applied AG coated glass, which allows “light trapping” or reduction of reflection and scattering of light.
While the N230 is getting the most attention for its high efficiency, Sanyo has another model in the N series – the N225 (225W) – and both are scheduled to be launched in Japan in Autumn 2010.

New Quantum Dot Photovoltaics Could Double Solar Cell Efficiency

by Cameron Scott

You’ve heard the statistic: enough solar power hits the Earth in an hour to meet our energy needs for an entire year. The trick is harnessing it. Today’s solar cells make use of just under a third of the energy hitting them, overheating to create “hot electrons” that escape before they can be converted into electricity. A study published in this week’s Science demonstrates a new type of solar technology could harness quantum dots to convert two-thirds of the sun’s energy into electrical power.

   

The technology utilizes semiconductor nanocrystals, or “quantum dots” — which slow the cooling of hot electrons to create time to grab them — and a titanium dioxide conductor to accomplish the task. A previous study pioneered the use of quantum dots to slow the electrons’ cooling. The recently documented breakthrough is significant for its use of an inexpensive titanium dioxide “wire.”
Besides taking the discovery from theoretical science into practical engineering, one big problem still remains: hot electrons also lose their energy as they travel along the wire.

Greener Appliances

Bosch Factory Tour Unveils 5 Keys to Buying Greener Appliances

by Evelyn Lee

In the small, unimposing town of New Bern, NC (infamously known as the birthplace of Pepsi-Cola) lies the only US appliance manufacturer with complete lines of Energy Star-certified dishwashers, washers, and refrigerators — Bosch. That’s right, the German Company. Surprised? It was the first of many surprises I discovered while touring their US manufacturing facility. Here are five lessons learned from Bosch that have me taking a second look at my appliances, where they come from, and what they are or are not doing for the environment.

  

1. Performance

Imagine a room filled with 50 dishwashers running through their various different cycles — do you think you could hear a pin drop? That might just be possible if they’re Bosch’s latest 800 Plus Dishwashers, which feature a LED indicator light that shines on the floor when it’s closed so you can tell whether or not the machine is actually running. If, like me, you are wondering why Bosch has so many machines running at once, you will be interested to hear that Bosch runs performance tests on each and every one of their machines prior to packaging and shipping to retailers. When looking a machine’s performance you have to decide what’s most important for you. If it’s efficiency you’re looking for, don’t stop at the Energy Star label. With so many products now sporting this government-backed certification, it is important to look at the small print and really asses how much electricity and water is being used each cycle. Which leads us to our next lesson…

2. Cost Savings in Efficiency & Rebate Programs

Cost savings do not depend solely upon the initial purchase price — they should also include the overall performance of the appliance itself. Bosch’s latest Vision line features the most energy and water-efficient full-sized front-load washers that are available in the U.S. (They also happen to be available in a variety of cool colors including: sliver, anthracite, sky, and sepia.)
A lot of manufacturers are offering additional rebates to those looking to make green changes in their homes. One quick way to find available rebates it to check out the SEEARP (State Energy Efficient Appliance Rebate Program). Bosch also has an available Rebate Resource Center for consumers to learn all about government, retailer, and Bosch rebates that are currently available.

3. Lifecycle Management

The last time my parents purchased a major appliance, the old one ended up in our garage, as a back-up fridge. (Really – a back-up fridge?!?) When considering the entire lifecycle of your appliance or future appliance, don’t forget to consider what happens after many years of holiday dinners and family bake-offs. In Bosch’s case, 90% of their cooking appliances by weight can be recycled, and wall ovens are at least 92% recyclable. How many of your current appliances will end-up in the junkyard?

4. Supply Chain Management

It takes many suppliers to build one product — especially with all the individual parts that come together in big appliances. Bosch helps motivate their individual suppliers to integrate more environmentally-conscious methods into their practices, especially when it comes to their shipping materials. In 2009 the company saved approximately 52,200 pallets and cardboard boxes through the use of returnable containers. When taking a hard look at the appliances that you’re purchasing, think out of the box and beyond the finished product to see where other sustainable efforts are being made – if any are being made at all.

5. A Sustainable Company

Earlier this winter Bosch was recognized for the second consecutive year as the Energy Star Partner of the Year for Appliances by the U.S. Department of Energy (DOE), which says a lot about the Germany company. One of its primary motivators to manufacture in New Bern, NC has to do with their desire to produce locally in the markets they sell in – reducing the associated environmental effects caused by shipping items overseas and meeting sustainable manufacturing goals.
I admit that the trip may have left me a little bit biased and my roaming designer eye has a tendency to lean towards a European aesthetic. However, the next time you go through the decision-making process to purchase your next big appliance consider the following: overall performance, cost savings, lifecycle & supply chain management, and the company’s overall commitment to sustainability. You might be surprised to find out that the most homegrown decision you can make just might be a European one.

Zero-Energy Bio Refrigerator Cools Your Food With Future Gel

by Brit Liggett

In a valiant effort to rethink the ubiquitous refrigerator — which has seen few design changes since the invention of freon refrigerators in the 1930’s — Russian designer Yuriy Dmitriev has unveiled a fresh-looking, gel-filled appliance of the future. His Bio Robot Refrigerator utilizes a special gel-like substance that suspends and cools food once inserted. Dmitriev’s design is one of 25 finalists in the Electrolux Design Lab competition, which challenged entrants with the task of redesigning modern appliances for the future.

 

The Bio Robot Refrigerator mounts on a wall — Dmitriev points out it can be mounted horizontally, vertically or even on the ceiling. The fridge does not have a motor or other traditional technology like most refrigerators, — the gel does all the work — so, 90% of the appliance is actual usable space. To use the fridge you basically shove food into it’s biopolymer gel — which has no odor and is not sticky — and it is suspended and cooled until you need it again.
Dmitriev notes that the cooling agents are the “bio robots” inherent in the gel that use luminescence — light generated in cold temperatures — to preserve food. Although this sounds super techy and fun, Dmitriev doesn’t really explain how it’s going to work, so we’re a little skeptical of the Bio Robot Refrigerator becoming a reality someday. Viability aside, the fridge is definitely a huge step forward in terms of rethinking the design of one of our most-used appliances. Probably the best thing about this concept machine is that it uses zero energy for cooling — it just needs energy for it’s little control pad. Compared to the typical modern fridge, which uses about 8% of a household’s energy, this nifty-looking gadget of the future could cut our energy use significantly.

Move Over OLEDs: Scientists Create Cheap, Fully Recyclable Lighting Material

by Brian Merchant, Brooklyn, New York

Photo via Gizmag
Swedish and American researchers have just developed a fully recyclable lighting component with what Science Daily is terms a "new super material": graphene. Graphene is both inexpensive to produce and is 100% recyclable, and could be used to create glowing wallpaper made out of plastic--much like OLEDs could. But graphene appears to improve on OLEDs in some very big ways . . .

As you know, we've been big fans of the very efficient, long-lasting Light Emitting Diodes and Organic LED technology. But as Science Daily notes, there are still problems:

Today's OLEDs have two drawbacks -- they are relatively expensive to produce, and the transparent electrode consists of the metal alloy indium tin oxide. The latter presents a problem because indium is both rare and expensive and moreover is complicated to recycle.

A graphene lattice
Researchers believe they've found a solution by creating an organic light-emitting electrochemical cell (LEC) with the transparent electrode made of the "carbon material graphene." Graphene is used instead of conventional metal electrodes--and since everything in an LEC, including the graphene, can be created from liquid solutions, they will be able to be produced through a printing process. This makes them much more efficient--and much less expensive--to create en masse than OLEDs. Researchers involved in the project say that graphene paves the way for cheap production of plastic-based lighting, perhaps for the first time.
So what does this graphene consist of? SD has the skinny:

Graphene consists of a single layer of carbon atoms and has many attractive properties as an electronic material. It has high conductivity, is virtually transparent, and can moreover be produced as a solution in the form of graphene oxide.

Of course, we'll have to wait until more tests are done to get a fuller idea of its lifecycle and range of applications, but this seems like pretty intriguing news indeed

GEOTHERMAL or GROUND SOURCE HEAT PUMPS

CONSUMER ENERGY CENTER on GEOTHERMAL or GROUND SOURCE HEAT PUMPS

Heat pumps move heat from one place to another - from outside to inside a home, for example. That's why they're called "heat pumps."
We explained the way that they work in the section "Central HVAC." Here's a simplified version of how a heat pump works:
All heat pumps have an outdoor unit (called a condenser) and an indoor unit (an evaporator coil).
A substance called a refrigerant carries the heat from one area to another. When compressed, it is a high temperature, high-pressure liquid. If it is allowed to expand, it turns into a low temperature, low pressure gas. The gas then absorbs heat.
In the winter the normal heat pump system extracts heat from outdoor air and transfers it inside where it is circulated through your home's ductwork by a fan.
Even cold air contains a great deal of heat; the temperature at which air no longer carries any heat is well below -200 degrees Fahrenheit. But the coldest temperature ever recorded in the lower 48 states was -70 degrees, recorded at Roger Pass, Montana on January 20, 1954. Obviously in such weather, a heat pump would have to work pretty hard to produce 68-degree temperatures inside your home.
That's why geothermal heat pumps are so efficient.
Geothermal heat pumps are similar to ordinary heat pumps, but instead of using heat found in outside air, they rely on the stable, even heat of the earth to provide heating, air conditioning and, in most cases, hot water.
From Montana's minus 70 degree temperature, to the highest temperature ever recorded in the U.S. - 134 degrees in Death Valley, California, in 1913 - many parts of the country experience seasonal temperature extremes. A few feet below the earth's surface, however, the ground remains at a relatively constant temperature. Although the temperatures vary according to latitude, at six feet underground, temperatures range from 45 degrees to 75 degrees Fahrenheit.
Ever been inside a cave in the summer? The air underground is a constant, cooler temperature than the air outside. During the winter, that same constant cave temperature is warmer than the air outside.
That's the principle behind geothermal heat pumps. In the winter, they move the heat from the earth into your house. In the summer, they pull the heat from your home and discharge it into the ground.
Studies show that approximately 70 percent of the energy used in a geothermal heat pump system is renewable energy from the ground. The earth's constant temperature is what makes geothermal heat pumps one of the most efficient, comfortable, and quiet heating and cooling technologies available today. While they may be more costly to install initially than regular heat pumps, they can produce markedly lower energy bills - 30 percent to 40 percent lower, according to estimates from the U.S. Environmental Protection Agency, who now includes geothermal heat pumps in the types of products rated in the EnergyStar® program. Because they are mechanically simple and outside parts of the system are below ground and protected from the weather, maintenance costs are often lower as well.
As an added benefit, systems can be equipped with a device called a "desuperheater" can heat household water, which circulates into the regular water heater tank. In the summer, heat that is taken from the house and would be expelled into the loop is used to heat the water for free. In the winter, the desuperheater can reduce water-heating costs by about half, while a conventional water heater meets the rest of the household's needs. In the spring and fall when temperatures are mild and the heat pump may not be operating at all, the regular water heater provides hot water.
How Do They Compare?
Surveys taken by utilities have found that homeowners using geothermal heat pumps rate them highly when compared to conventional systems. Figures indicate that more than 95 percent of all geothermal heat pump owners would recommend a similar system to their friends and family. 

Cost
As a rule of thumb, a geothermal heat pump system costs about $2,500 per ton of capacity. The typically sized home would use a three-ton unit costing roughly $7,500. That initial cost is nearly twice the price of a regular heat pump system that would probably cost about $4,000, with air conditioning.
You will have to, however, add the cost of drilling to this total amount. The final cost will depend on whether your system will drill vertically deep underground or will put the loops in a horizontal fashion a shorter distance below ground. The cost of drilling can run anywhere from $10,000 to $30,000, or more depending on the terrain and other local factors.
Added to an already built home an replacing an existing HVAC unit, an efficient geothermal system saves enough on utility bills that the investment can be recouped in five to ten years. 

Durability
Geothermal heat pumps are durable and require little maintenance. They have fewer mechanical components than other systems, and most of those components are underground, sheltered from the weather. The underground piping used in the system is often guaranteed to last 25 to 50 years and is virtually worry-free. The components inside the house are small and easily accessible for maintenance. Warm and cool air are distributed through ductwork, just as in a regular forced-air system.
Since geothermal systems have no outside condensing units like air conditioners, they are quieter to operate.
How Do They Work?
Remember, a geothermal heat pump doesn't create heat by burning fuel, like a furnace does. Instead, in winter it collects the Earth's natural heat through a series of pipes, called a loop, installed below the surface of the ground or submersed in a pond or lake. Fluid circulates through the loop and carries the heat to the house. There, an electrically driven compressor and a heat exchanger concentrate the Earth's energy and release it inside the home at a higher temperature. Ductwork distributes the heat to different rooms.
In summer, the process is reversed. The underground loop draws excess heat from the house and allows it to be absorbed by the Earth. The system cools your home in the same way that a refrigerator keeps your food cool - by drawing heat from the interior, not by blowing in cold air.
The geothermal loop that is buried underground is typically made of high-density polyethylene, a tough plastic that is extraordinarily durable but which allows heat to pass through efficiently. When installers connect sections of pipe, they heat fuse the joints, making the connections stronger than the pipe itself. The fluid in the loop is water or an environmentally safe antifreeze solution that circulates through the pipes in a closed system.
Another type of geothermal system uses a loop of copper piping placed underground. When refrigerant is pumped through the loop, heat is transferred directly through the copper to the earth. 

Types of Loops
Geothermal heat pump systems are usually not do-it-yourself projects. To ensure good results, the piping should be installed by professionals who follow procedures established by the International Ground Source Heat Pump Association (IGSHPA). Designing the system also calls for professional expertise: the length of the loop depends upon a number of factors, including the type of loop configuration used; your home's heating and air conditioning load; local soil conditions and landscaping; and the severity of your climate. Larger homes requiring more heating or air conditioning generally need larger loops than smaller homes. Homes in climates where temperatures are extreme also generally require larger loops.
Here are the typical loop configurations:

Horizontal Ground Closed Loops

This type is usually the most cost effective when trenches are easy to dig and the size of the yard is adequate. Workers use trenchers or backhoes to dig the trenches three to six feet below the ground in which they lay a series of parallel plastic pipes. They backfill the trench, taking care not to allow sharp rocks or debris to damage the pipes. Fluid runs through the pipe in a closed system. A typical horizontal loop will be 400 to 600 feet long for each ton of heating and cooling.

Vertical Ground Closed Loops

This type of loop is used where there is little yard space, when surface rocks make digging impractical, or when you want to disrupt the landscape as little as possible. Vertical holes 150 to 450 feet deep - much like wells - are bored in the ground, and a single loop of pipe with a U-bend at the bottom is inserted before the hole is backfilled. Each vertical pipe is then connected to a horizontal underground pipe that carries fluid in a closed system to and from the indoor exchange unit. Vertical loops are generally more expensive to install, but require less piping than horizontal loops because the Earth's temperature is more stable farther below the surface.

Pond Closed Loops

This type of loop design may be the most economical when a home is near a body of water such as a shallow pond or lake. Fluid circulates underwater through polyethylene piping in a closed system, just as it does through ground loops. The pipes may be coiled in a slinky shape to fit more of it into a given amount of space. Since it is a closed system, it results in no adverse impacts on the aquatic system.
Although they are less applicable to California, there are other loop systems described at the Geothermal Heat Pump Consortium's Web Site. These include an Open Loop System in which ground water is pumped into and out of a building, transferring its heat in the process; and Standing Column Well Systems, which can be up to 1,500 feet deep and can also furnish potable water.
In a few places, developers have installed large community loops, which are shared by all of the homes in a housing project.
To date, geothermal heat pumps are an under-used technology, merely because few people are aware of it's potential. The Department of Energy's Office of Geothermal Technologies, however, wants to increase installations of geothermal systems to about 400,000 a year by 2005. If the goal is reached, that would mean that 2 million systems would be in service, saving consumers over $400 million per year in energy bills and reducing U.S. greenhouse gas emissions by over 1 million metric tons of carbon each year.

Are Ground Source Heat Pumps (AKA Geothermal Systems) A Good Choice?

by Lloyd Alter, Toronto

Every time I write about ground source heat pumps, (like in my post Blowing Hot and Cold on Ground Source Heat Pumps) the commenters are enraged, saying " If I were a geothermal contractor or manufacturer I would have asked that this be removed for falsely conveying what geothermal has to offer " and "engineering degree would probably help too."

But I just got my licence to practice architecture thirty years ago this month and obviously don't know what I am talking about, so it is great to find a real expert, like Alex Wilson at Green Building Advisor, saying much the same thing.

Right off the bat I am excited about his post, for he agrees with me about calling them ground source heat pumps instead of geothermal. (and if you want to see more people calling me an idiot, read the comments at Jargon Watch: Geothermal vs Ground Source Heat Pump) Alex writes:

A ground-source heat pump (GSHP) is also referred to as a "geothermal" heat pump, though I prefer the former terminology, to avoid confusion with true geothermal energy systems that rely on elevated temperatures deep underground from the Earth's mantle.

After that he could sell me on vinyl replacement windows, let alone GSHPs. Instead he goes on to point out:
They are rarely as efficient as promised; they advertise a Coefficient of Performance of 3.5 times that of straight resistance electric heating, but turn out to be around 2.5. (John Straube at Buildingscience.com notes that the COP rated efficiency may not include the energy required for the pump, suggesting that "This electrical energy can be significant, particularly if the loop is long, the pipes are small, or the flow resistance within the heat pump unit is large." That may account for the difference.)
Alex also notes that the GSHPs run on electricity, which for much of America comes from coal; if you go back to the source, efficiency the numbers are a lot lower. If you care about your carbon footprint, it is actually worse than running on natural gas.a commenter did the numbers:
1. Burn natural gas at 92% efficiency = 1.09 MMBtu of fuel which makes 130 lb CO2.
2. Burn #2 fuel oil at 83% efficiency = 1.2 MMBtu and 175 lb CO2
3. Run a ground-source heat pump and purchase 0.33 MMBtu of electricity which has made 140 lb CO2.
These numbers do not apply if you live in Quebec or parts of the Continent where you can purchase green energy from hydro or renewables.
But ultimately, Alex's objection is the same as mine: they are really expensive and there are better places to spend your money.

The reason I'm not a huge proponent of GSHPs is that they're really expensive. Most of the expense is due to the cost of digging trenches and laying tubing....It is not unusual to hear about GSHPs in Vermont costing as much as $35,000 for typical homes. For the same investment, one could spend $30,000 reducing heating loads (insulating, air sealing, replacing windows, etc.) and install a state-of-the-art mini-split heat pump.

Not only does natural gas have a lower carbon footprint than a coal-fired GSHP, but America is awash in the stuff, so much so that they are thinking of reversing the flow in the pipelines and exporting it to Canada. The development of shale gas in the States changes everything, and anyone who says that you are going to get a return on investment by switching your heating from gas to electricity is basically lying.
We need to invest in reducing our consumption, not in buying green gizmos. That is why I am so enamoured of Passivhaus design. There, the technology is simple: add a shitload of insulation and eliminate leaks. Reduce demand rather than switching supply. That is the path to energy independence and a lower carbon footprint.

Filtered Water In 2 Minutes with New UV Light Bottle Invention

by Jaymi Heimbuch

Image via James Dyson Award
Most portable water filters use carbon filters, special membranes with microscopic openings, or chemicals like chlorine or iodine to clean the water and make it save for drinking. However, one of the best systems for purifying water is actually with ultraviolet light. But how do you get an ultraviolet light purification system into a small portable water bottle that can be used anywhere? One design and technology graduate has figured it out, and already won the UK branch of the prestigious James Dyson Award for his invention.

According to BBC, Timothy Whitehead, a graduate from Loughborough University, came up with the idea for the bottle while traveling in Zambia. Rather than using chlorine or iodine tabs which take half an hour to work and leave a gross taste in the water, this new bottle first filters particles four microns or larger from the water, then uses ultraviolet light (powered by wind-up) to kill 99.9% of bacteria and viruses. All within two minutes and all without altering the taste.
The Pure bottle is already quite advanced in the development process, including an "original filter designed which filters any soiled water down to 4 micron in particle size (fully scientifically proven); a wind-up Ultra violet light system has been produced, including a custom designed PCB to monitor winding frequency and to give user feedback when the water is sterile. The casing has been designed for both prototype production and manufacture."
Now that the invention has proven itself in the UK, it will face off with other finalists from around the world in October.

Papercrete

I would especially like to continue to share this information with my architect/builder/artist/other friends as well as my good friend, Bob Gregory of Texas Disposal Systems (TDS), in that Bob could possibly turn this into a viable reuse product through TDS ingenuity.

This product can be used along with traditional construction and other innovative product use for schools, governmental buildings and commercial applications in addition to residential and art creations.

Prior to being sealed, papercrete can be carved into almost any shape opening up interesting architectural/art possibilities.

There is an organic bed and breakfast, Eve's Garden, in Eve’s Garden located in the beautiful high mountain desert of West Texas, in Marathon that is built completely from papercrete. Check out Eve's garden at www.evesgarden.org 

Thanks for taking your time to read this, research it more if it interests you and feel free to pass it on.

PAPERCRETE Current papercrete construction methods and papercrete research are covered in detail on this site. Papercrete construction involves using waste paper for affordable, sustainable housing.  In the United States, we discard enough paper each year to build a wall 48 feet high around the entire perimeter of the country. Even though about 45 percent of discarded paper is recycled annually, 55 percent or 48 million tons of paper is thrown away or goes into the landfills. Figuring conservatively, it takes about fifteen trees to make a ton of paper. That means that 720 million trees are used once and then buried in a landfill each year. We are experimenting with ways to turn this prodigious amount of waste into low-cost, high-value sustainable housing. Given the skyrocketing costs of building materials & construction, and the pressing need for homes, it is just a matter of time before papercrete will begin to  take its place as an acceptable and even desirable residential construction material.           The press is trailer-mounted and runs on a small gas engine. Blocks are ejected on their side and can be handled immediately. We are also working on a 5-yard mixer with dump bed and pump, which will feed the press! Presses and mixers are still in development, but we expect to have hard information and pricing by March, 2010.
	Below - Clyde T. Curry’s imaginative designs at Eve’s Garden. Below - Tom Curry's vaulted papercrete cottage - Sunny Glen. To the greatest degree possible, we obtain our information from first-hand observation, interviews with experts, experimentation, engineering research and actual construction. However, formulas and methods evolve and change as we learn more, and any material can be dangerous if mixed or installed improperly. Therefore, please read this Disclaimer. 3 mins (DSL or Cable only.) 51 secs(DSL or Cable only.)       Above -The living room and dining room in Zach Rabon's boomerang-shaped 3200 sq. ft. papercrete home.
WHAT IS PAPERCRETE? There are a number of ways to make construction material from paper. The generic term for the method described here is "papercrete". There are a number of variations of papercrete, such as fibrous concrete or fibercrete, fibrous cement, padobe and fidobe. See more about these variations under Mixes. Barry J. Fuller tosses blocks to Lex Terry for stacking at the building site. Papercrete is a tricky term. The name seems to imply a mix of paper and concrete, hence paper-crete. But more accurately, only the Portland cement part of concrete is used in the mix - if used at all. Arguably, it could have been called "paperment." Papercrete may be mixed in many ways. Different types of papercrete contain 50-80 percent waste paper! Up to now, there are no hard and fast rules, but recommended standards will undoubtedly be established in the future. The basic constituents are water and nearly any kind of paper. Cardboard, glossy magazine stock, advertising brochures, junk mail or just about any other type of  "mixed (lower) grade" paper is acceptable.  Some types of  paper work better than others, but all types work.. Newsprint is best. Waterproofed paper and cardboard, such as butcher paper, beer cartons, etc. are harder to break down in water. Catalogs, magazines and other publications are fine in and of themselves, but some have a stringy, rubbery, sticky spine, which is also water resistant. Breaking down this kind of material in the mixing process can't be done very well. Small fragments and strings of these materials are almost always present in the final mix. When using papercrete containing the unwanted material in a finish, such as in stucco or plaster, the unwanted fragments sometimes show up on the surface, but this is not a serious problem. Papercrete can be sculpted into any shape and painted. Practitioners simply flick out the offending pieces as they apply the finish. Papercrete additives can be: Portland cement, sand, dirt, clay, glass, or even "fly ash" - an ash at one time freely emitted into the atmosphere - now at least partially captured from power plant smoke stacks. We are experimenting with powdered glass, rice hull ash, Styrofoam and other additives.
THE ENVIRONMENTAL BONUS The environment sends papercrete Valentines. Using papercrete in construction: Incentivizes the recycling of waste paper, especially in communities with no recycling services. Saves landfill space. Keeps paper processing & printing chemicals out of the water table. Saves trees and other construction resources, which would have been used in place of papercrete for walls and roof. Saves additional trees and other construction resources, which would have been used to "build out" or finish the interior and exterior of the structure. R-Value better than code - saves a significant amount of energy during  the lifetime of the structure. Provides new construction jobs. Provides low-cost, sustainable housing. Individuals and small contractors can get into papercrete. There are no harmful by-products or excessive energy use in the production of papercrete. While it can be argued that Portland cement is not environmentally friendly, it is not used in all types of papercrete, and when it is, it represents a fairly small percentage of the cured material by volume. One of the most advantageous properties of papercrete is the way paper fibers hold Portland cement - or perhaps the way Portland cement adheres to paper fibers. When the water added to the paper and Portland cement drains from the mix, it comes out almost completely clear. There is no messy and eco-unfriendly cement sediment left on the ground, running into waterways, etc. Papercrete can be produced using solar energy. The only power needed is for mixing - and pumping water. Its R-Value is rated between 2.0 and 3.0 per inch. Since walls in a one or two-story house will be 12-16 inches thick, the long-term energy savings of building with papercrete will be a bonanza for the homeowner and the environment.
THE JOB BONUS There will be a positive impact on employment in areas producing papercrete. Homes and other buildings of up to 3300 sq. ft. have been built with papercrete for about $25/sq.ft. That doesn't include labor, but even when labor is factored in, papercrete homes can be built, with all the conveniences, for twenty to thirty percent less than conventional housing. The preparation and installation of papercrete does not require significant outlays of capital or a great deal of additional training. Individuals and new or existing small construction enterprises can add papercrete to their businesses for very little extra money or time. Papercrete batch plants, for building entire sub-developments, are in the prototype stages now and will be available soon. These operations will cost more, but still be within reach for the small sub-contractor.

Michelle Kaufmann Imagines a Future of Green Building

by Michelle Kaufmann, San Francisco, California 04.22.10

This guest post was written by Architect Michelle Kaufmann in celebration of the 40th Anniversary of Earth Day.
TreeHugger: What are the major advances have you seen (in your field) during the past 40 years? What, if any, were the major failures?
Michelle Kaufmann: Well, 40 years ago I was still three years shy of preschool, so I'll focus more on the last 20 years. The adoption of more green building principles, the advent of green rating programs for commercial and residential buildings, alternative energy systems and more prefabrication are a few of the game changers that come immediately to mind.

The development and use of technology in design has definitely raised the bar. It is now possible to make a scale model of a building of almost any shape, run a handheld digitizer over it's surface and send that info to a hard drive. From there that data can be used to create scaled drawings, or in the case of a project I collaborated on recently, the data was sent to a CNC milling machine that manufactured full scale parts of a clients house. Really amazing stuff when you actually consider what a short time we have been using computers.
A few notable mentions in the Darwin Design Awards:
The idea that bigger is better, resulting in the birth of "McMansions," an ill conceived, ugly, wasteful blight on the landscape. Need I say more? The insane notion that a "new house smell" was something to be desired. If you can smell it, it most likely is still off gassing and is toxic! Those not-so-timeless design style fads; 70's brutalism, 80's post-modernism, 90's deconstructivism).
Our use of technology in architecture is still in its infancy. We have been using technology to try to dominate our environment rather than using it to help us better integrate into our ecosystem. How exciting as we look to the immediate future and innovation happening all around us! We have all the pieces; we just need to figure out how best to put them together.
TH: What does a bright green future look like in this field?
MK: I dream of a future where our buildings are not only non off-gassing and have zero toxins, but that they actually improve our health. Imagine buildings that are integrated into the ecosystem, taking what are typically seen as problems (such as affordable food production, fresh water shortages, and increased waste production) and make them into beautiful design solutions such as edible building skins and porous, breathable walls that "drink," purify and store water for the building inhabitants. Imagine buildings that are intelligent and can adjust to maximize comfort and efficiencies at different seasons and times of day (we wear different clothing at different times of year, and out buildings should also be able adjust their skins). Imagine a future with zero waste, where buildings produce their own energy, collect their own water, and improve the lives of the inhabitants.
TH: How would we realistically transition into that sort of ideal situation?
MK: Here are 5 things we can do to make this future a reality:
1. Mashup of Past and Present
Remembering the best design principles from the past and mixing those with advanced technologies is the best recipe for truly sustainable design.
2. Cradle to Cradle
Principles described in the book Cradle to Cradle (by William McDonough and Dr. Michael Braungart) are becoming a reality through the work of their C2C certification program and work with agencies to help provide roadmaps for achieving zero waste while simultaneously driving economic, ecological and equitable growth. I strongly believe this is a path for much innovation in the design and construction industry.
3. Designing for Deconstruction
Knowing our needs and desires change over time, we can design for efficient deconstruction (rather than demolition) resulting in zero waste. For example, currently, if one remodels their kitchen most of the countertops, cabinets and plumbing fixtures are ruined with the removal because of typical construction techniques and how they were originally constructed. However, if we design and build an entire kitchen module that could be removed (floors, walls, mechanical systems and all) and a new kitchen module inserted, the old kitchen stays intact and can be reused by someone else with no waste produced.
4. Present Meaningful Information Clearly
Much like nutrition labels for food, we need more accurate and easy to understand information on products and buildings to help us make better choices. Carbon Emissions labels (including embodied energy) on all products, buildings, foods and services will make a significant difference.
5. Interdisciplinary Collaboration
Some of the most interesting work being done is through collaboration of different disciplines. Imagine a design team comprised of a molecular biologist, a farmer, a building automation specialist as well as an architect. The focused intensity of all these individuals, who might not normally be in the same room together, could be apt to ignite some truly amazing and innovative solutions to current day problems.

http://www.inhabitat.com/2010/03/19/solar-city-tower-for-rio-olympics-giant-energy-generating-waterfall/

Solar City Tower for Rio Olympics is a Giant Energy Generating Waterfall

by Bridgette Meinhold, 03/19/10

This renewable energy generating tower located on the coast of Rio is one of the first buildings we’ve seen designed for the 2016 Rio Olympics, and boy, is it crazy! (In case you didn’t notice, it’s also a waterfall.) The Solar City Tower is designed by Zurich-based RAFAA Architecture & Design, and features a large solar system to generate power during the day and a pumped water storage system to generate power at night. RAFAA’s goal is that a symbolic tower such as this can serve as a starting point for a global green movement and help make the 2016 Olympic Games more sustainable.

The self-sustaining tower for the 2016 Olympic Games is designed to create renewable energy for use in the Olympic Village as well as the city of Rio. A large solar power plant generates energy during the day. Any excess power not used during the day is utilized to pump seawater into a storage tank within the tower. At night, the water is released to power turbines, which will provide nighttime power for the city. On special occasions water is pumped out to create a waterfall over the edges of the building, which RAFAA says will be, “a symbol for the forces of nature.” Info on the size of the solar and pumped water storage system is not available yet.
Access to the eco tower is gained through an urban plaza and amphitheater 60 meters above sea level, which can be used for social gatherings. On the ocean side of the 105 meter tower (behind the waterfall) is a cafeteria and shop. An elevator takes visitors up to the top floor where an observation deck offers 360 views of the ocean and city. At level 90.5, a bungee platform is available for adventurous visitors.

Earthbag Building

Building with earthbags (sometimes called sandbags) is both old and new. Sandbags have long been used, particularly by the military, for creating strong, protective barriers, or for flood control. The same reasons that make them useful for these applications carry over to creating housing. Since the walls are so substantial, they resist all kinds of severe weather (or even bullets) and also stand up to natural calamities such as earthquakes and floods. They can be erected simply and quickly with readily available components, for very little money.

Earthbag building fills a unique niche in the quest for sustainable architecture. The bags can be filled with local, natural materials, which lowers the embodied energy commonly associated with the manufacture and transportation of building materials. The fill material is generally of mineral composition and is not subject to decomposition (even when damp), attractive to vermin, or burnable...in other word it is extremely durable. The fill material is generally completely non-toxic and will not offgas noxious fumes into the building.

Earthbags have the tremendous advantage of providing either thermal mass or insulation, depending on what the bags are filled with. When filled with soil they provide thermal mass, but when filled with lighter weight materials, such as crushed volcanic stone, perlite, vermiculite, or rice hulls, they provide insulation. The bags can even act as natural non-wicking, somewhat insulated foundations when they are filled with gravel.

Because the earthbags can be stacked in a wide variety of shapes, including domes, they have the potential to virtually eliminate the need for common tensile materials in the structure, especially the wood and steel often used for roofs. This not only saves more energy (and pollution), but also helps save our forests, which are increasingly necessary for sequestering carbon.

Another aspect of sustainability is found in the economy of this method. The fill material can be literally "dirt cheap," especially if on-site soil is used. The earthbags themselves can often be purchased as misprints or recycled grain sacks, but even when new are not particularly expensive. Burlap bags were traditionally used for this purpose, and they work fine but are subject to rot. Polypropylene bags have superior strength and durability, as long as they are kept away from too much sunlight. For permanent housing the bags should be covered with some kind of plaster for protection, but this plaster can also be earthen and not particularly costly.

The ease and simplicity of building with earthbags should also be mentioned, since there is much unskilled labor available around the world that can be tapped for using this technology. One person familiar with the basics of earthbag building can easily train others to assist in the erection of a building. This not only makes the process more affordable, but also more feasible in remote areas where many common building skills are not to be found.

 http://earthbagbuilding.com/index.htm

Small Domes

This three-page how-to shows the steps used in building Riceland, a 14' diameter earthbag/papercrete dome. This prototype dome could serve as a model for emergency shelters, cabins, studios, garden sheds, etc. It should work well in earthquake-prone areas and places subject to flooding, winds, and hurricanes. It could be used as quick housing for people made homeless by natural disasters. One of the most practical structures on a small farmstead is a multi-purpose garden structure that can serve as a storage shed or cool pantry above ground, or as a root cellar or storm shelter below ground. You can build this Low-Cost Multipurpose Minibuilding for about $300 using earthbag construction. This was written by Owen Geiger and is excerpted from The Mother Earth News. The Hermit's Dome I ran across a web site that advertised building emergency shelters out of sandbags. I was quite intrigued by the concept and decided to try to build one for myself. My daughter was not too enthused about the idea. She didn't think that an 81-year-old man with a bad back should take on that kind of task, although she knew it was no use to try talking me out of it. We made a 9-foot 6-inch diameter flexible form rammed earth structure for meditation purposes. We call it A Meditation Kiva, a hut, a dome, a wonder. We felt the deep connection to earth and people throughout history as we filled the bags and slapped on the staw and clay plaster. How peacefully meditative it was to work with this medium, without mechanization or complicated tools and sophisticated know-how! Kaki Hunter and Doni Kiffmeyer describe how they built their Honey House. The merits of "Flexible Form Rammed Earth" are in its use of cost-effective materials, simple construction methods and the durable resistance to the ravages of fires, hurricanes, flooding, termites and, as Nader Khalili has proven in Southern California, earthquakes. The OM Dome My inspiration for earthbag building was on the beach in Thailand. I was pondering the creation of a sound temple and looking for local building materials. While on the beach I watched fishermen fill used woven poly bags with sand and stack them into a retaining wall. Epiphany! I remembered a research paper I did in college on earthen building and Nader Khalili. At Terrasante Village, in the fall of 2000, our first experiment with earth was a simple, partially subterranian adobe-in-a-bag (aka earthbag) 12 foot circular structure with interior ferrocement retaining wall below grade. We called this EarthDome House. Material for the bag walls was excavated from the interior space and the walls were stuccoed with 1” chicken wire mesh for extra strength. Featured are the Earthbag Domes of Akio Inoue of Tenri University, Japan. He assisted building these on the university campus, at an earthquake site near Jamnagar, India, and in Entebe, Uganda. These domes are being considered for use as refugee shelters in the region, because they provide good protection from bullets, fire, wind, and rain. Building an earthbag dome describes hows this 4 meter diameter dome was built at a sustainability education center in Australia. Some of the unique features integrated into the design of the dome include: a rubble trench footing containing a French drain, appropriate passive solar design, rammed earth flooring and a living roof.

Angel's Dome in Mexico was built using volcanic stone as fill material, barrels as window forms, and has a small loft. There will be a skylight at the top, and the windows feature eyebrows. It has a nice curved buttress for the entryway.

A Little Dome in Durban, South Africa The boys really liked to learn, though some prefer to learn one aspect and then keep doing that. It seems that in each place only one or two have the mental makeup to really try to absorb everything from A to Z. The brothers who were building got more and more inspired when it was nearing completion and in the end we finished a early. Four  Dome Cottages in Thailand would provide a better standard of acommodation for the volunteers. The training and building went well with so many people involved. A few had specially come to do the training and others from the Burmese refugee community were very keen to aquire these new skills. The children just had great fun and in the end a house to claim as built by them. QUSAYR AL-JAWASREH, designed by Kikuma Wantanabe, is a Community Center for the Al-Jawasreh Village, located in South Shounah near the Dead Sea in Jordan. It is a public facility open to the local community, where educational and vocational programs are provided. New Zealand Hermitage We've decided to “start small” and build an earthbag dome sauna. This will give us some practice with getting a feel for our sand-clay mixture and the amount of work involved in stuffing and laying our tubing. Our goal is to build a home for as little money as possible, and teach others to do the same. If you have played with clay, chances are you can build a dome. The hut is 8' in diameter (wide enough to comfortably lay down inside) and stands over 7' high inside at the center. I used 200 bags for a total cost of less than $40. Building the hut was inexpensive, but required a lot of labor. As far as I'm concerned it has provided many hours of silent retreat for me and it was indeed a ... labor of love. An earthbag model dome is part of the ISEGERO village in Eastern Uganda. It is the beginning of the ecovillage in the Mpambo Afrikan Multiversity, started in August, 2009. The university aims towards Africa cultural revival. They are trying to construct an ecovollage made of earthbag in which the African culture is reflected. One small model dome was constructed to teach them about this technology.Complex Domes
Kelly and Rosana Hart's earthbag/papercrete home completed in 2000. This 1250 sq.ft. home was made with the earthbags filled with socria (crushed volcanic stone) and covered with papercrete plaster. The passive solar design performs well at over 8,000 ft. in the Colorado mountains.
This Earthbag Clinic in the Philippines was coordinated by Illac Diaz, the young Phillipine visionary who has spearheaded many such earthbag projects in the area, including several schools. There is no text describing the process of building, but the many photos tell most of the story. You will notice that the bag material was removed after the fill had set up and before the building was plastered. Featured are the Earthbag Domes of Akio Inoue of Tenri University, Japan. He assisted building these on the university campus, at an earthquake site near Jamnagar, India, and in Entebe, Uganda. These domes are being considered for use as refugee shelters in the region, because they provide good protection from bullets, fire, wind, and rain. Using a technique developed by Cal Earth in California, architect Nader Kahlili worked with the Pegasus Children's Project to build a small sustainable village of over 40 “super adobe domes” to provide permanent shelter. This project accommodates 80 children, 10 staff, and a small school near Kathmandu, Nepal, in the Himalaya Mountains — the first of its kind for the region. Hootenanny in Baja Together with the earth, sun, and sea, we will craft an abode of beauty, simplicity and comfort.  Working together, we'll expand our horizons - how to build a safe and beautiful home for a small cost. I made the project under time, a little over budget, and am significantly happier with the result than I had envisioned.  So, I'm a happy man. Uganda Ecovillage. In 2008 Sunny Tsai volunteered to assist a team of two architects and eight professors, under the direction of Akio Inoue of Tenri University, Japan, to construct an ecovillage by Lake Victoria, Uganda, East Africa. This ecovillage was designed by architect Kikuma Watanabe of the Kochi University of Technology.
Jorge Dominguez has been helping his friend Mark Hanson build the first Code Permitted Hawaiian Dome Home. This is a copy of a desert earthbag dome adapted to super heavy rain. It took Mark like a year to get his permit. Lots of patience required. This dome is going to be sold to a retired couple. It is not meant for a family with kids. The Joshua Tree Home is the eventual residence of Mark Reppert. It is a double eco dome designed by Cal-Earth. San Bernardino County gave Mark a permit to build the house. The building regulations there are some of the toughest in the country. We were an international crew of builders. There were 5 core builders with extra volunteers on occasion. The Warsaw Dome project was built in Poland as a demonstration of inexpensive, sustainable building techniques that others might employ. This is one of many such projects initiated by the Earth, Hands, and Houses organization founded by Paulina Wojciechowska, author of Building with Earth: A Guide to Flexible-Form Earthbag Construction . Two retaining walls and the beginning of an earthbag tube dome home in Midpines, California. "Michele and Sara-Ann standing next to our first window form. We're fast approaching 3000 feet as of April 5, 2007." HomeGrown HideAways, a natural building school in Kentucky helped John Capillo build his Kentucky Dome Home while running a workshop to teach people the fundamentals of earthbag building. The code officials were incredibly open to new things and gave John his permit without hassle. His design has a 16 foot dome with a larger circle coming off the dome that has a wooden roof. Krpasundarananda is a Meditation teacher with Ananda Marga and has been a Monk since 1991. The Eco-Dome in Ananda Nagar, India is a showpiece to inspire other members and teachers and he hopes one or two of the laborers or visiting villagers get the idea and will want to learn more. He'll be happy to help them to build in their own villages. Building the Double Dome in Mongolia was fun and again I learned a lot. I thought I came to teach, but then found that I have hardly any experience how to work with a bunch of unruly teenage boys and girls, what to say...I didn't even speak the language! The kids are very proud of their work and the dome will be used for teenage programs. Mickey Mouse in Morelia, Mexico We should get sponsorship from Disney Land... Mickey Mouse is easy to recognise. Oops, they may charge us royalties. The Sandbag Shelters of Nader Khalili I will show you what to me, is an exellent way to made architecture, how we can make, with few and natural resources, great space design, and at the same time, solve differents social problems, one of the principal motives and preocupations of modern architecture. Tim Hall's Earthbag Home in Hawaii shows, mostly in pictures, how a CalEarth-style Superadobe home was built, using cement-stabilized tubular bags that were then burned away before the building was plastered.

Just east of Bisbee, Arizona this Ransom Ranch Dome project was completed after studying and admiring Nader Khalili's alternative building work since 1985. I finally apprenticed with him at Cal-Earth in November 2007.

This Dome Experiment with Large Windows has a 24' inside diameter at the base, rising on a ‘catenary' curvature to sloping truncation around 16' above grade. This was attempted as a fairly aggressive exploration of structural potential with this system in several capacities, and quite cognizantly surrendered to the tests of time. I can only stand behind this as an artist of sorts, as it is beyond most established protocol of construction.Vertical Wall Homes
Baraka's House evolved after she asked me to help her design her custom earthbag home. She had very specific ideas about the shape and room arrangement, but wanted some input as to what was practical with earthbags and how to accomplish many details of construction. She also wanted a passive solar design and wanted my my advice about this as well. This tastefully designed home was built on a shoestring budget by owner/builder Alison Kennedy in Moab, Utah. The 1,000 square foot earthbag home is the first permitted earthbag house in Utah. Alison in-filled earthbags between concrete and wood posts. A concrete block bond beam was mortared into place on top of the wall. Described by Kaki Hunter and Doni Kiffmeyer. Steve and Carol Escott built a two story home on the remote island of Rum Cay, Bahamas, assisted by Kaki Hunter and Doni Kiffmeyer. This Sand Castle features a first floor made with earthbags filled with sand and crushed coral, upon which a second story, framed house would be constructed and covered with a hip-style roof. Robin's House built near San Miguel de Allende in Mexico is based on a traditional Southwestern adobe and has an open floor plan. Theo describes the building of The Sun House in Haiti. "Rice, barley, wheat all come in poly bags which we've saved. They will be used to hold a mix of moistened sand and clay. The bags will be laid out much like bricks or blocks and barbed wire will be used as mortar between the rows." We spent a year intensively researching alternatives to mainstream building techniques and settled on a plan that fit our very small budget, was simple and low tech, that two reasonably fit persons could build alone. We chose to build a Buddhist Hermitage, which will be the primary residence for the hermitage staff. After months of design work the dome shape was rejected, in favor of sqaure corners and straight walls to accomodate living spaces inside. Several Eternally Solar Earthbag Projects in South Africa demonstrate a unique approach that features poly bags that have been partitioned into three compartments lengthwise, so that the two outer compartments can be filled with soil while the central compartment is left unfilled and creates a void to insulated the center of the wall. Project in Belize This project is presented primarily as a photo essay, but the wealth of details makes it nearly self-explanitory. Kaki Hunter and Doni Kiffmeyer, the authors of Earthbag Building are present, and their trademark methods are employed. Tatu Penrith's Sandbag Hideaway is a haven on top of the world and an appealing terracotta and green house with thick walls that give it an earthy, handmade look. 'Sandbags are much cheaper than bricks, as well as being warm in winter and cool in summer. You can use unskilled labour; we used the women from Sir Lowry's Village down the road, and they sang while they packed the bags.' The Gypsy Farm Adventure chronicles several years in the life of the Newberry family while they build a hybrid earthbag, cob, strawbale, pole frame, ferrocement home in Georgia. "I will continue this journey we once called a Newberry adventure, yet today I see this small adventure as part of a greater journey with it's connections to the others on this planet as we travel together." La Casa de Tierra is a rental house located in Ojochal, also called Playa Tortuga (Turtle Beach), on the Southern Pacific coast in Costa Rica. Judy and her son live on the island of Dominica. They are working to build a earthbag home for Judy. The idea of an earthbag home is that it is resistant to extreme climate occurrences such as hurricanes and tornadoes. It is also supposed to be able to handle earthquakes. Judy hopes to be prepared to deal with whatever challenges come her way.History

by Kelly Hart

The idea of making walls by stacking bags of sand or earth has been around for at least a century. Originally sand bags were used for flood control and military bunkers because they are easy to transport to where they need to be used, fast to assemble, inexpensive, and effective at their task of warding off both water and bullets.
At first natural materials such as burlap were used to manufacture the bags; more recently woven polypropylene has become the preferred material because of its superior strength. The burlap will actually last a bit longer if subjected to sunlight, but it will eventually rot if left damp, whereas polypropylene is unaffected by moisture.
Because of this history of military and flood control, the use of sandbags has generally been associated with the construction of temporary structures or barriers. Using sandbags to actually build houses or permanent structures has been a relatively recent innovation.

In 1976 Gernot Minke at the Research Laboratory for Experimental Building at Kassel Polytechnic College in Germany began to investigate the question of how natural building materials like sand and gravel could be used for building houses without the necessity of using binders. The use of fabric-packed bulk material was found to be a cost-efficient approach. They used pumice to pack in the bags, because it weighs less and has better thermal insulating properties than ordinary sand and gravel. Their first successful experiments were with corbelled dome shapes ( an inverted catenary) which was obtained with the aid of a rotating vertical template mounted at the center of the structure.

1978, a prototype house using an earthquake-proof stacked-bag type of construction was built in Guatemala. They used cotton bags soaked in lime-wash to protect the material from rot and insects. When flattened, the bags measured roughly 8 X 10 cm. Vertical bamboo poles placed on both sides of the bags and interconnected with wire loops gave the stacked bags stability. The bamboo rods were fixed to the foundation and to the horizontal tie beam at the top. (See this page for more about this.)

It was an Iranian-born architect named Nader Khalili who has popularized the notion of building permanent structures with bags filled with earthen materials. Actually his first concept was to fill the bags with moon dust! Attending a 1984 NASA symposium for brainstorming ways to build shelters on the moon, Khalili coupled the old sandbag idea with the ancient adobe dome and arch construction methods from his homeland in the Middle East. He realized that bags filled with lunar “dirt” could be stacked into domes or vaults to provide shelter.
Khalili came up with a further refinement on this building concept on Earth: for a more permanent, shock-resistant structure, why not place strands of barbed wire between the courses of bags, thus unifying the shell into a more monolithic structure?
At first Khalili was filling his experimental bags with desert sand, but then he evolved his idea of “superadobe,” where bags or long tubes of polypropylene bag material would be filled with a moistened adobe soil that would dry into large adobe blocks. In this case the original bag material was merely the initial form and would not necessarily be an integral part of the eventual structure.
Soon after these first experiments, Khalili began publicizing his work through newspaper and magazine articles and conducting workshops and seminars on the techniques that he was perfecting. Many people who read about his work, visited his compound in Hesperia , California , or studied with him there, decided to go ahead with their own experiments with his ideas.
Among these “early adopters” were Joe Kennedy, Paulina Wojziekowska, Kaki Hunter and Doni Kiffmeyer, Akio Inoue, and Kelly Hart. I believe that it was Joe Kennedy who coined the more general term “earthbag” to suggest that the bag could contain a variety of earthen materials.
Paulina Wojciechowska was the first to write an entire book on the topic of earthbag building: Building with Earth: A Guide to Flexible-Form Earthbag Construction was published in 2001. This featured some of her early experiments done at Khalili's CalEarth, along with several other case histories.

Akio Inoue, from Tenri University in Japan, has done extensive experimentation with earthbag construction, both on the campus of the University and in India and Africa where many other domes have been built for assistance programs.
Kaki Hunter and Doni Kiffmeyer (a couple) became enamored with earthbag construction after studying with Khalili, and worked on a variety of projects, both for themselves and for clients. In 2004 they wrote and got published another book,  Earthbag Building : the Tools, Tricks and Techniques , based on their particular experience.

Kelly Hart (the author of this article) first began experimenting with earthbag building in 1997, after being exposed to the concept while producing his video program, A Sampler of Alternative Homes: Approaching Sustainable Architecture . He later documented his experience in actually building his own home in another program titled Building with Bags: How We Made Our Experimental Earthbag/Papercrete Home . Both of these programs are now available as DVD's.
In the meantime, Nader Khalili was continuing the promotion of his “Superadobe” technique and eventually decided to patent the idea, which he obtained in the U. S. in 1999, using very general terms that cover using bags made of any material being filled with virtually any material, and combining these with barbed wired between the courses. While having made many public statements that this concept was his gift to humanity, he obviously wanted to capitalize on the potential economic reward.
Many of us who had been engaged in promoting earthbag building on our own were contacted by Khalili and asked to enter into contracts with him in order to continue our work. It didn't take much research to discover that his patent could easily be disqualified because he had been publicizing his techniques through various media for at least four years before he even applied for his patent. Patent law clearly states that such publicity occurring prior to one year before the patent application would disqualify it for consideration.

So now the door is wide open for anyone to take this concept and run with it, and more people are doing so all the time, all over the world. While Khalili (and most of his students) have focused primarily on using the bags to form large adobe blocks, others have tried filling the bags with a variety of other materials, such as crushed volcanic rock, crushed coral, non-adobe soils, gravel, and rice hulls.
Earthbag building is unique among all other building technologies in that it can be either insulation or thermal mass, depending on what the bags are filled with. This is a very important distinction, because these characteristics of a wall greatly influence how comfortable, economical, and ecological any given system will be.
Safety is of prime concern with all building technologies, and much experimentation and testing has been done to establish guidelines for many ways of building. Khalili has established a relationship with the building department in Hesperia , California where CalEarth is located, an area where earthquakes are naturally a great danger. In 1993 live-load tests to simulate seismic, snow and wind loads were performed on a number of domed earthbag structures at CalEarth and these exceeded code requirements by 200%.
In 1995 dynamic and static load tests were performed on several prototypes for a planned Hesperia Museum and Nature Center to be constructed using Khalili's Superadobe concepts with both dome and vault shapes. All of these tests exceeded ICBO and City of Hesperia requirements.
In 2006, at the request of Dr. Owen Geiger of the Geiger Research Institute of Sustainable Building, the Department of Civil and Mechanical Engineering of the U.S. Military Academy at West Point conducted several controlled and computer-monitored tests to determine the ability of polypropylene earthbags filled with sand, local soil, and rubble to withstand vertical loads. Their written report concluded that “overall, the earthbags show promise as a low cost building alternative. Very cheap, and easy to construct, they have proven durable under loads that will be seen in a single story residential home. More testing should prove the reliability and usefulness of earthbags.”
Despite the success of these tests, earthbag building concepts have yet to be incorporated into the International Residential Building Code. Obviously more enlightened acceptance of the demonstrated viability of earthbag building needs to occur!

It is difficult to know how many residences and other earthbag structures have been made at this point, probably hundreds if not thousands. Many of us have been promoting the technique for use as emergency shelters, and certainly some have been built for this reason. It is easy for folks to accept this way of building temporary shelters because it fits the historical model of sandbag use.
But many of us have also built substantial homes using earthbags, and in the process realized how truly versatile and sustainable the technique is. I wouldn't be surprised if many of these earthbag homes are still standing long after their conventional counterparts built contemporaneously have disintegrated.