Wednesday, February 27, 2008

Open Source Block Maker

Blocks Made From Compressed Earth

Schematics for the machine that made these blocks is going to be available free to anyone who wants to make inexpensive construction blocks.

The Liberator Project, the design for a Compressed Earth Block (CEB) machine is an online collaboration, with the final design to be available to all.

The tech. literature for CEBs should show somewhere that working with CEBs is a little tricky. The blocks don’t do well in tension. When the wind blows on an exterior wall it causes the wall to want to bend, possibly making one face of the wall “stretch”. CEBs are a brittle material and they don’t really stretch, instead the walls crack. Designers must overcome this tendency by designing CEB walls and their applied loads heavy enough to keep the inside face from stretching.

You should check out some of the following cool links:


CEB Press

Sustainable Design Update

Tuesday, February 05, 2008

Greenhouse Gas or Fuel Source?

Cow Fart Outdooralex via Flickr
Cow Expressing Displeasure With Photographer

What can we do with cow emissions and animal waste emissions? Animal waste can be collected in a biodigester to make methane gas. Small farms can make enough gas to cook their meals, and larger farms can run their equipment and/or run generators that feed power into the grid. Farm animals belch and otherwise emit copious amounts of methane, a powerful greenhouse gas.

Near New Zealand scientists have discovered a bug that eats only methane. The bug can live in extreme conditions, and I hope it can be safely added to cattle feed to reduce the gas generated by our bovine friends.

From National Geographic:

The reason VOCs are a concern at all is because they're one of the components that contributes to the formation of ozone, which is the primary ingredient of smog," Malay said.

But VOCs aren't the only worrisome gases that emanate from livestock. Scientists say animals such as cattle and sheep are responsible for around 20 percent of global methane emissions.

Methane, a greenhouse gas, is believed to be a major driver of climate change, because it traps 21 times as much heat in the atmosphere as carbon dioxide.

"In more rural communities as much as 50 percent of the methane comes from livestock," said Jamie Newbold, professor at the Institute of Rural Sciences in Aberystwyth, Wales.

Newbold is among a growing number of scientists now investigating how farm animals influence atmospheric pollution. The field is sometimes dismissed by critics as "fart science."

Via: Practical Environmentalist

Photo: Outdooralex Via Flickr