Articles by Gar Lipow

Built to scale

Small and medium size wind generators of about 100 KW each are playing an important role in the power supplied by the Alaska Village Electric Cooperative (AVEC) -- a non-profit customer-owned electric co-op serving 52 villages throughout interior and western Alaska.

Wind power on this scale, and in these conditions, is not cheap. Unlike megawatt scale wind turbines which cost around $1,600 per KW of installed capacity, these smaller generators run around $10,000 per installed KW. Part of that cost is simply a matter of buying on a smaller scale. But according to Brent Petrie, Key Accounts Manager for AVEC, the harsh Alaska conditions are responsible for much of this cost. Building in permafrost has always been tough, especially when that permafrost undergoes seasonal melts that turns it to mush and marsh. As an environmentally sensitive utility, AVEC is careful to minimize damage during installation. Overall, electricity costs from such small scale generation are estimated by Petrie to run around 15 cents per kWh -- three to four times the price of larger scale wind farms in milder conditions.

But the same conditions that drive the price of wind electricity for the AVEC customers drive up conventional sources even more. Fuel is shipped by barge to the small isolated communities, or even flows in, meaning that electricity is supplied by diesel generators run on the most expensive of fossil fuels. Since transporting large amount of fuel is an expensive prospect, normally fuel is delivered only once a year.

According to Petrie, AVEC tries to make sure that as a cushion each village has storage capacity for 13 months of fuel. Building a diesel storage facility on permafrost is an expensive prospect too. Combined fuel purchase, shipping, and storage for diesel in these villages runs between 13 cents and 25 cents per kWh -- even before purchase and maintenance of generators is considered. Overall, electricity to these villages averages 45 cents per kWh; so the 15 cents per kWh for wind electricity represents a real savings.

Dam it all

Tucuruí, Brazil's second largest dam has many times the GHG emissions of a natural gas plant of the same capacity -- though there is fierce argument over whether that output substantially exceeds what a natural watercourse would produce. (The emissions are due to methane from trapped organic matter in the dam.)

There is now a proposal to tap that methane to run gas turbines and produce electricity, reducing the emissions many times, since CO2 from burning the methane has a much lower impact than the methane itself. It would also close to double the electrical output from the dam. This seems very close to an acknowledgment that critics of methane from dams are correct. Outside of estuaries, I don't know many natural water courses that might be tapped in such a way. I have to admit that it is an ingenious solution to the problems of dams as methane sources.

In case you mistook Schwarzenegger for a green

Ahnold cuts transit funding.

(via Michael O'Hare)

A funny

You decide if the following web comic applies to any viewpoint you are familiar with.