Modesto Irrigation District officials say buying power on the open market can be an expensive proposition.
Consider these wholesale prices:
For October 2007 delivery:
- $58 per megawatt hour (off-peak, when demand is lowest).
For 2008 delivery (anytime during the year):
- $71 per megawatt hour (off-peak).
For wind power, add about $5 to $10 per megawatt hour to the above prices.
Other types of renewable energy aren't traded regularly, according to MID spokeswoman Kate Hora.
"There's no established marketplace like a stock or commodity exchange for it," Hora said. "These are all special 'deals,' where a utility either builds a generator or buys the entire output (usually) of a particular generator at a negotiated price."
Hora said renewable energy types other than wind (geothermal, biomass, solar) are substantially more expensive.
Wind power, Hora said, is the only renewable whose price is even close to competitive with conventional resources such as natural gas.