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funded by Sustainable Development Technology Canada, will demonstrate a 1-megawatt turbine with a 2-megawatt-hour storage capability. After which the company plans to scale up by “orders of magnitude.”

from http://jason.cox2.name/?p=310

From http://fatknowledge.blogspot.com/2007/10/buddhist-economics.html:

The aim of Western economics is to maximize “standard of living” by the amount of annual consumption, with more being better.

The aim of Buddhist economics is to maximize well-being while minimizing consumption.

177 MW solar thermal power plant Ausra said that project is expected to generate enough electricity to power more than 120,000 homes.
Plant:
Ausra started up the reflector production line at the 130,000 square foot plant, which the company said would also supply the absorber tubes and other key components for solar thermal power projects.
Ausra said the Las Vegas facility would employ a staff of 50, producing more than 700 megawatts of solar collectors annually at full capacity.

Maple Ridge wind project ... 195 turbines soar above Tug Hill, 400 feet high, their 130-foot long blades spinning at 14 revolutions per minute. farmers paid ... a minimum of $6,600 a year for every turbine.

The plants will cover 12.5 square miles of central California with solar panels, and in the middle of a sunny day will generate about 800 megawatts of power, roughly equal to the size of a large coal-burning power plant or a small nuclear plant. A megawatt is enough power to run a large Wal-Mart store.

The coalition plans to buy at least 200 megawatts of renewable power, enough new generation to serve 200,000 homes

www.processimpact.com/goodies.shtml)

from the oil drum
back-of-the-envelope calculations
Kyle Schuant
the energy E required to compress air at 25C is,

E = 110,000 x ln (P1/P2) /m3/mol

There are about 45mol air in 1m3, so,

E = 110,000 x ln (P1/P2) /m3

This howstuffworks article tells us that an air car tank might have 300lt at 4,561psi, which is 29,999,087.707 - call it 30,000 kPa. Atmospheric pressure is 101.3kPa. 300lt at 30,000kPa will be 90,000lt at atmospheric pressure, or 90m3. And so we get,

E = 110,000 x ln (30,000 / 101.3) x 90
= 110,000 x 5.69 x 90
= 56,331,000J
which is 15.6kWhr

However, a company which supplies air compressors tells us that "Most systems typically waste 25 to 50 percent of the energy required to generate compressed air that actually provides useful work."

Let's be optimistic and assume that with lots of air cars zooming around, service stations will buy the most efficient (expensive) compressors. So we get just a 25% loss. This brings us to 20.9kWhr.

Let's round it up to 21kWhr to refill the tank. Again, this isn't the air car referred to in the article, but it gives us an idea of the order of magnitude.

21kWhr to travel 200km.

A regular small city car gets about 10km/lt. Petrol costs about $1.30/lt, and causes 2.32kg CO2e/lt. So to go 200km in a regular car would cost $26 and cause 46.4kg CO2e in emissions.

Electricity from coal cost $0.1355/kWh and 1.21kg CO2e/kWh, so the 200km journey would cost $2.85 and cause 34.9kg CO2e in emissions.

Electricity from wind costs $0.19/kWh and causes 0.04kg CO2e/kWh. So the 200km journey would cost $3.99 and cause 0.84kg CO2e in emissions.

The average Australian car is driven 15,000km annually. That'd be 75 refills, or 1,575kWh energy in all. That's not bad when the average household uses 6,000kWhr annually.

419,000 on 11/2007

11 megawatts of electricity, enough to power 6000 homes

Vermont Energy Investment Corporation
A water heater blanket (about $20) could save you $34 a year for a gas heater; $54 for an electric one. Water heaters made 10 years ago aren't well insulated. If yours dates to 1997 or before, it can lose about 3 degrees Fahrenheit of heat an hour.

Scheer, Hermann, 1944- The solar economy :renewable energy for a sustainable global future /Hermann Scheer. London ; Sterling, VA : Earthscan, 2002.


Dewey Library - Stacks | TJ808.S3313 2002