Appropriate Technology Roundup #28 [7/19/08]

1. Solar Water Heaters Now Mandatory In Hawaii from Metaefficient

Hawaii has become the first state to require solar water heaters in new homes. The bill was signed into law by Governor Linda Lingle, a Republican. It requires the energy-saving systems in homes starting in 2010. It prohibits issuing building permits for single-family homes that do not have solar water heaters. Hawaii relies on imported fossil fuels more than any other state, with about 90 percent of its energy sources coming from foreign countries, according to state data.

Related: 90% Of Israeli Homes Have Solar Water Heaters also from Metaefficient

2. Mobile Phone Ingenuity in Africa from Afrigadget

Dual Sim

One of the more interesting innovations is the development of a dual SIM card hack so that users can access multiple carriers.

“This product has two SIM card slots in a single phone – primarily to support price sensitive/prudent consumers who wish to optimise their call costs by maintaining SIM cards from two different phone operators. As in many countries – calls to a customer using a different Ghanaian operator cost slightly more than those on the same network.”

3. Trash-fed Generator Tested in Baghdad from Ecogeek

Trash Fed Generator

The US military is looking to cut back on two things in Iraq: fuel consumption and trash. So they’re finally getting on board with alternative fuel sources, using the trash they don’t want to get the fuel for electricity they need.

In March, we let you know that trash-to-fuel generators were getting shipped to Iraq. Well, they’ve arrived and are being tested.

4. Electric bike project from MAKE

DIY Electric Bike

The bike itself started as a $150 walmart special. Within 30 minutes of getting it home I had stripped everything off the frame. Then bolted on 2 brushless hub motors rated for 500 watts. Next came drilling some holes through the frame and bolting on some sheet aluminium panels to hold the electronics. There are 2 battery packs( 36volt 8amp nimh cells ), 2 36volt 3 amp charges for them and 2 speed controllers. Both speed controllers are tied to the throttle grip and you can switch between front wheel drive, rear wheel or both. 2/wheel drive is a lot of fun when you go offroad with it. And the side covers and tank where made from scrap pink insulation core then covered with fibreglass cloth and epoxy resin. I was trying for a Thunderbirds look, maybe I need to make wheel disks.

5. Small-scale Hydro Allows AK Family to Live Off-Grid from Treehugger

When I think about people who live off the grid the first thing that pops to mind isn’t hydropower. Solar panels, small wind turbines, geothermal? Yes. Technology that dates back to 1870? No. Granted, the number of sites where small-scale hydro can work for a home are more limited than those which are suitable for other technologies. Perhaps that’s part of it. In any case, as an example of what can be done if the site suits witness the Shaul family of Juneau, Alaska.

6. 3 Out Of 4 U.S. Ethanol Plants At Risk Of Shutting Down from Earth 2 Tech

[C]lose to three quarters of U.S. ethanol plants, or 123 of America’s 160 operating ethanol plants, are at risk of being shuttered in the coming months, according to Citigroup analyst David Driscoll. (hat tip MarketWatch). Small and mid-sized ethanol plants are in trouble due to a record-setting spike in corn prices, bumped up by the Midwest floods and increasing demand. This news comes after Citigroup downgraded all the major publicly traded ethanol players including Archer Daniels Midland, BioFuel Energy and VeraSun Energy.

7. Communal Bikes in Boston from Bostonist

[City Councilor John Connolly] filed legislation yesterday to order a hearing on bringing shared bikes to the city. It’ll be like ZipCar for bikes.