Further responses to Nick on the reliability of wind

Nick, we are discussing changing out power generating systems. The peak capacity you discuss is part of the system we should be replacing. There are two questions about wind:
1. How useful is it in decreasing CO2 emissions right now?
2. What role can it play in a post carbon electrical generating system.

The answer to question one appears to be less than expected, and the total impact is not clear. Is the current subsidy on wind cost effective in reducing CO2 use? This is a clear unknown. Would, for example diverting the wind generating subsidy to more efficient electrical use yield a greater CO2 emission savings? Suppose the government took the money it now pays for wind subsidies, bought florescent light bulbs with it, and gave the light bulbs to anyone who wanted them. Would giving away florescent light bulbs create more CO2 savings.

How about the government giving homeowners solar water heating systems? What sort of CO2 savings would come from such a program?

Finally some studies of the actual CO2 savings from wind conclude that they are modest at best. Dieter Helm, Energy Economist and Fellow in Economics, New College, Oxford, observes:
“What we know, is the wind blows sufficient for these windmills to be producing about 35%, perhaps 40% of the time. So the paradox of building windmills is that you have to build a lot of ordinary power stations to back them up and those are going to be almost certainly gas in the short to medium term and that’s what’s required."

Wind in the present is tied to the use of CO2 generating fossil fuels.

Despite advocates claims about CO2 savings, we need much better data. The whole matter needs careful and impartial research.

This then is the case in the present. What about the future?

There are several problems with wind in a post carbon future. We have focused some attention to on what role wind can play in a future electrical generating system. I am looking right now at graphs of wind generation data from Amarillo, Texas (http://www.stanford.edu/group/efmh/winds/power_monthly/ama_powerm.html). I picked out Amarillo because it is regarded as having very good wind resources. Wind generators in Amarillo have excellent capacity factors [at least by wind generation standards]. The graph for August clearly shows wind capacity factors dropping to almost zero in mid morning and not rebounding until late afternoon. [This is true everywhere in Texas.] Thus Texas wind resources cannot be counted on during the hottest hours of summer days. A few years ago the staff of the Electric Reliability Council of Texas (ERCOT) argued that exactly 2% of rated wind resources of Texas should be included in the accounting of as summer peak. There is a good case that are right. Summer peak power producers should be producing electricity at 1:00 PM on summer days. But almost everywhere wind capacity factors drop to unacceptable levels in the middle of hot summer days.

Are there enough good wind spots in the country to provide reliable electricity? A glance at the Stanford data suggests that we cannot expect consistent, steady generation from wind anywhere, and that national wind output varies significantly by time of day and season of the year. But summer winds seem light almost everywhere. Given what we know about wind, there appears little doubt that it cannot deliver power at the very moment when power is in demand. This is simply unacceptable, and raises serious doubts about the role of wind in a post carbon electrical generating system.