Owners of Austin-area homes built with bales of straw and other natural materials like the idea that they are having less of an impact on the environment, and they're getting health and economic benefits as well.
The bales for the 18-inch walls have been covered with stucco on the home's exterior and smooth adobe plaster on the interior, helping to keep the home earthy, comfortable and quiet. His average monthly utility bill is about $55. And the large, deep window sills are perfect for his two kids to sit and read their favorite books.
In addition to straw bales, green builders also are using rammed earth, or dirt compressed into building blocks; cob, a mixture of adobe and straw; and aerated concrete blocks.
The building project started last fall, with carpenters erecting the post-and-beam structure that would support the weight of the roof. Then on a sunny November day, people came to the Rainey's bale-raising party from as far away as Houston and Oklahoma. News of straw-bale raising workshops is spread through word-of-mouth and Internet message boards.
For six hours, everyone worked to raise the walls, using more than 300 bales of straw. Some stacked the bales, some droves stakes through the bales to anchor them together. Others tied bamboo stakes together on both sides of the bale wall, giving it stability until plastering.
Rainey estimates it will take three more months for contractors to finish the electrical wiring and plumbing. Then the Raineys will hold another workshop, led by a local contractor, this time covering the topic of plastering interior walls. Before the walls are plastered, Rainey must trim the edges of the straw bales to ensure a smooth wall surface. Small recesses will be cut into the walls for niches, and wood studs will be added in preplanned areas in order to have wall support to hang pictures.
So far, the biggest surprise in the building project was related to insurance coverage. In short, his insurer told him it wouldn't cover a straw-bale structure. But Rainey said he talked with other people in town who know about sustainable building and found a carrier who covered such homes.
Obregon said that many people wrongly think that straw bales are highly flammable, and that this leads some insurers to refuse coverage. But Obregon said that structural engineers have tested straw for fire safety and discovered that when properly installed, these structures do not burn easily.
"The heat transfer is not an issue. It's great," Obregon said. In fact, densely packed bales limit oxygen flow.
"The biggest concern for our area can be the moisture level in straw bales," he said. It's important to keep the bales moisture-free, especially before the wall-raising, he said. It's also important to waterproof the exterior walls, to create wide roof overhangs and to seal the doors and windows tightly.
Vicki Howard of Austin chose an alternative to straw-bale construction. She decided that living in a house built of dirt would be a clean, although counterintuitive, solution to her health problems. So she lives in what's called a rammed-earth home.
full article
Saturday, 18 August 2007
Green Earth Fuels' Facility Goes Beyond Two Million Gallons
On Thursday, Green Earth Fuels announced that to date its new Galena Park facility on Houston's Ship Channel, which opened for operations on July 24th of this year, has produced 2.4 million gallons of biodiesel fuel, with all of the fuel meeting the rigorous quality control requirements of ASTM specifications D6751.
Green Earth Fuel's first process line, capable of producing 45 million gallons per year (mmgpy) of quality biodiesel produced its first two batches of biodiesel from Soybean oil, and these met the national ASTM (American Society of Testing and Materials) specifications. This first of two planned trains was, according to the company, completed on schedule and on budget.
Biodiesel is the fastest-growing fuel in the U.S. according to the Department of Energy. Biodiesel is a renewable fuel derived from natural sources such as vegetable oils and animal fats which can be blended seamlessly into diesel fuel. U.S. biodiesel production last year reached an estimated 225 million gallons. The federal government wants biodiesel to account for five percent, or an estimated 3 billion gallons, of all fuel produced in the U.S by 2015.
Critics say that we have a long way to go toward refining and making cost-effective biofuels such as biodiesel. A study published last year by Oregon State University backs up this critical stance. The study shows that industry has yet to develop biofuels that are as energy efficient as the gasoline we make from petroleum. Energy efficiency is the measure of how much usable energy for a given purpose is derived from a certain amount of input energy.
The OSU study discovered corn-derived ethanol to be only 20% energy efficient. Biodiesel fuel was found to have 69% energy efficiency. Gasoline made from petroleum has an energy efficiency of 75%.
Critics also are concerned that putting too much emphasis on biofuels will result in too little space for food-purpose agriculture, disrupting the environment and sharply driving up food prices.
full article
Green Earth Fuel's first process line, capable of producing 45 million gallons per year (mmgpy) of quality biodiesel produced its first two batches of biodiesel from Soybean oil, and these met the national ASTM (American Society of Testing and Materials) specifications. This first of two planned trains was, according to the company, completed on schedule and on budget.
Biodiesel is the fastest-growing fuel in the U.S. according to the Department of Energy. Biodiesel is a renewable fuel derived from natural sources such as vegetable oils and animal fats which can be blended seamlessly into diesel fuel. U.S. biodiesel production last year reached an estimated 225 million gallons. The federal government wants biodiesel to account for five percent, or an estimated 3 billion gallons, of all fuel produced in the U.S by 2015.
Critics say that we have a long way to go toward refining and making cost-effective biofuels such as biodiesel. A study published last year by Oregon State University backs up this critical stance. The study shows that industry has yet to develop biofuels that are as energy efficient as the gasoline we make from petroleum. Energy efficiency is the measure of how much usable energy for a given purpose is derived from a certain amount of input energy.
The OSU study discovered corn-derived ethanol to be only 20% energy efficient. Biodiesel fuel was found to have 69% energy efficiency. Gasoline made from petroleum has an energy efficiency of 75%.
Critics also are concerned that putting too much emphasis on biofuels will result in too little space for food-purpose agriculture, disrupting the environment and sharply driving up food prices.
full article
Friday, 17 August 2007
EU biofuel policy is a 'mistake'
The EU target of ensuring 10% of petrol and diesel comes from renewable sources by 2020 is not an effective way to curb carbon emissions, researchers say.
A team of UK-based scientists suggested that reforestation and habitat protection was a better option.
Writing in Science, they said forests could absorb up to nine times more CO2 than the production of biofuels could achieve on the same area of land.
The growth of biofuels was also leading to more deforestation, they added.
"The prime reason for the renewables obligation was to mitigate carbon dioxide (CO2) emissions," said Renton Righelato, one of the study's co-authors.
"In our view this is a mistaken policy because it is less effective than reforesting," he told BBC News.
Dr Righelato, chairman of the World Land Trust, added that the policy could actually lead to more deforestation as nations turned to countries outside of the EU to meet the growing demand for biofuels.
full article
A team of UK-based scientists suggested that reforestation and habitat protection was a better option.
Writing in Science, they said forests could absorb up to nine times more CO2 than the production of biofuels could achieve on the same area of land.
The growth of biofuels was also leading to more deforestation, they added.
"The prime reason for the renewables obligation was to mitigate carbon dioxide (CO2) emissions," said Renton Righelato, one of the study's co-authors.
"In our view this is a mistaken policy because it is less effective than reforesting," he told BBC News.
Dr Righelato, chairman of the World Land Trust, added that the policy could actually lead to more deforestation as nations turned to countries outside of the EU to meet the growing demand for biofuels.
full article
Marko Spiegel wants to help people design houses that are heated with one watt of energy per square foot of space - a mere tenth of what's normally needed.
That means the energy equivalent of three 100-watt light bulbs could heat your 300-square-foot living room on a very cold day.
Spiegel, an engineer based in LaFox, will talk about his One-Watt-House at 9:30 a.m. Saturday at the Sixth Annual Illinois Renewable Energy and Sustainable Lifestyle Fair, which will continue Aug. 12 in Oregon, Ill., southwest of Rockford.
These homes currently cost 10 percent to 40 percent more than regular construction, Spiegel said.
He emphasizes that the homes are not only less expensive to operate, but are more comfortable and healthier, too.
One-Watt-Houses are so energy efficient that they do not require conventional furnaces, said Spiegel, and these homes use one-tenth the energy of an average Midwest building.
Consumers are ready to build energy-efficient houses, said the engineer, because energy is becoming more expensive and people are learning how pollution damages the earth.
Zaderej, a mechanical engineer, hopes to develop modular systems for the key elements of the house.
This could reduce the costs of the house by as much as 40 percent, he said.
Like Zaderej's home, these houses would be built with structured insulating panels, which are a sandwich of a boardlike material with solid foam insulation in the middle.
Homes and components would be designed to fit with standard items like windows.
Although existing buildings cannot be retrofitted to the same energy standards as new construction, auditing the energy lost from buildings and designing solutions is part of Spiegel's business.
While One-Watt-Houses can be built with a variety of styles and materials, there are minimal standards and characteristics.
• The home design is simpler and compact.
• Walls and foundation are super-insulated and spots that leak cold or heat are eliminated as much as possible.
The walls' R-value, a measure of resistance to heat flow, is about 40, compared with up to 28 recommended by the Energy Star program, a federally sponsored system to let consumers know how efficient products are.
• Windows have three panes and are gas filled and are very efficient. The home's north side has fewer windows.
Other features of these well-engineered houses include being airtight and a heat transferring ventilation system.
Methods that can be used to heat the house include a hot-water heater, bringing in air heated or cooled from underground, solar power, wood-pellet ovens or geothermal systems. Backup air conditioning should be provided by the smallest unit possible, he said.
One of the features Zaderej is testing on the Oregon house is a metal roof that acts as a solar collector to help warm part of the building.
Metal roofing also reduces air-conditioning needs, he said.
The house is heated with an electric hot water heater and also has a basement designed to pre-heat or pre-cool air for the home.
full article
That means the energy equivalent of three 100-watt light bulbs could heat your 300-square-foot living room on a very cold day.
Spiegel, an engineer based in LaFox, will talk about his One-Watt-House at 9:30 a.m. Saturday at the Sixth Annual Illinois Renewable Energy and Sustainable Lifestyle Fair, which will continue Aug. 12 in Oregon, Ill., southwest of Rockford.
These homes currently cost 10 percent to 40 percent more than regular construction, Spiegel said.
He emphasizes that the homes are not only less expensive to operate, but are more comfortable and healthier, too.
One-Watt-Houses are so energy efficient that they do not require conventional furnaces, said Spiegel, and these homes use one-tenth the energy of an average Midwest building.
Consumers are ready to build energy-efficient houses, said the engineer, because energy is becoming more expensive and people are learning how pollution damages the earth.
Zaderej, a mechanical engineer, hopes to develop modular systems for the key elements of the house.
This could reduce the costs of the house by as much as 40 percent, he said.
Like Zaderej's home, these houses would be built with structured insulating panels, which are a sandwich of a boardlike material with solid foam insulation in the middle.
Homes and components would be designed to fit with standard items like windows.
Although existing buildings cannot be retrofitted to the same energy standards as new construction, auditing the energy lost from buildings and designing solutions is part of Spiegel's business.
While One-Watt-Houses can be built with a variety of styles and materials, there are minimal standards and characteristics.
• The home design is simpler and compact.
• Walls and foundation are super-insulated and spots that leak cold or heat are eliminated as much as possible.
The walls' R-value, a measure of resistance to heat flow, is about 40, compared with up to 28 recommended by the Energy Star program, a federally sponsored system to let consumers know how efficient products are.
• Windows have three panes and are gas filled and are very efficient. The home's north side has fewer windows.
Other features of these well-engineered houses include being airtight and a heat transferring ventilation system.
Methods that can be used to heat the house include a hot-water heater, bringing in air heated or cooled from underground, solar power, wood-pellet ovens or geothermal systems. Backup air conditioning should be provided by the smallest unit possible, he said.
One of the features Zaderej is testing on the Oregon house is a metal roof that acts as a solar collector to help warm part of the building.
Metal roofing also reduces air-conditioning needs, he said.
The house is heated with an electric hot water heater and also has a basement designed to pre-heat or pre-cool air for the home.
full article
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