Appropriate Technology Roundup #22 [12/13/07]

AIDG’s somewhat weekly roundup of appropriate technology stories. This week: underwater turbines, lighter-than-air turbines, turbines powering cell phone base stations in Africa and more.

1. Harnessing the Power of the Gulf Stream from NPR via Green Daily

Underwater turbines to harness the Gulf Stream's energy
Illustration Source: FAU Florida Center for Electronic Communications

As described by Green Daily:

Secretary of the Interior Dick Kempthorne recently made the announcement that we should be using the ocean’s wind and waves as our servants, harvesting their seeming toddler-like hyperactive energy for our own myriad needs. Sounds megalomaniac, but hey, it’s clean.

For a company that is currently harnessing energy through underwater turbines, see Verdant Power

Vid of folks at Verdant Power installing turbine in East River in NYC

2. San Francisco Converts Entire Diesel Vehicle Fleet to Biodiesel from Treehugger

San Francisco hit another major green milestone earlier this week when Mayor Gavin Newsom announced that the city had converted its fleet of approximately 1,500 diesel vehicles to run on biodiesel – a month earlier than the goal it had set in 2006. Fire engines, ambulances and MUNI buses, amongst others, will now run on B20, a blend of 20% biofuel and 80% diesel fuel.

Note: The writers of the press release from the SF mayor’s office made a wee mistake. You don’t convert a diesel vehicle to biodiesel. Diesel engines can automatically use biodiesel. One instance where you would have to convert however is if you have a pre-1993 diesel vehicle. Biodiesel tends to dissolve rubber gaskets and fuel lines over time. Newer vehicles however use non-rubber materials for these parts and are for the most part already biodiesel compatible. Check with the manufacturer if there is any doubt.

Also w00t:

San Francisco’s progress on biodiesel conversion puts San Francisco on track to meet its commitments under the Local Climate Action Plan, which calls for reducing greenhouse gas emissions to 20% below 1990 levels by 2012.

For more basic info of biodiesel see this post from the Practical environmentalist and Using Biodiesel from Utah Biodiesel Supply.

3. Geocell systems has come up with a faster way of building a flood wall that they want to see replace slow, labor-intensive sand bag walls.

Geocell Assembly
Assembly of Geocell Rapid Deployment Flood Wall

Loading the Geocell grids
Loading the grids of the Flood Wall

Find more info on Geocell’s training page.

4. More Wind Powered Cell Phone Base Stations in Africa from Afrigadget

Motorola’s customer based trial of a wind and solar powered network in Namibia.

Duration: 2 min 15 secs

5. Gray Water Package Units from Brac Systems from Treehugger

6. Cheap and Easy Solar Heater from Treehugger

Update:Check out comments section on Treehugger post. The consensus seems to be that this project is of dubious utility.

7. Rural Solar Power in Brazil from Sustainable Design Update

In 2001, Fabio Rosa, a pioneer of rural electrification in Brazil, had a flash of inspiration: he would rent solar energy to rural low income families.

Rentals would allow people to purchase electricity with monthly payments, similar to how grid-connected households pay. In addition solar rentals in Brazil are smart business, rentals are not subject to Brazil’s mind numbingly huge sales tax that adds more than 50% to the cost of a purchase.

I think Soluz used to do something similar in the Dominican Republic.

8. Google Sketchup for Dummies from Boing Boing

See Also: The Sketchup Show for tutorials and podcasts

MAKE SketchUp Workbench video tutorial

9. It looks an Internet hoax, but apparently it’s real.

Mageen Power Air Rotor System (M.A.R.S.)


MARS is a lighter-than-air tethered wind turbine that rotates about a horizontal axis in response to wind, generating electrical energy. This electrical energy is transferred down the 1000-foot tether for immediate use, or to a set of batteries for later use, or to the power grid. Helium sustains MARS and allows it to ascend to a higher altitude than traditional wind turbines. MARS captures the energy available in the 600 to 1000-foot low level and nocturnal jet streams that exist almost everywhere. MARS rotation also generates the “Magnus effect” which provides additional lift, keeps the MARS stabilized, and positions it within a very controlled and restricted location to adhere to FAA (Federal Aviation Administration) & Transport Canada guidelines.

10. LiveRoof: Instant Gratification for a Green Roof from Treehugger

[A] modular removable green roof system that is delivered fully grown.

Living Roof info