Mike Carrell wrote:
It was millions of windmills, not millions of wind towers.
That's true. A large wind turbine produces 1 or 2 MW nameplate, 0.3 to 0.6 MW actual. The wind tower being planned in Australia will produce 200 MW nameplate, and I suppose about the same actual. So it would take ~300 times more wind turbines than towers to produce an equivalent amount of energy. And 4 or 5 towers will produce as much power as one average U.S. nuclear plant. As I pointed out yesterday, it would take 2,500 towers to supply the US, or millions of wind turbines.
The big difference is land area. The wind power in takes up 10,000 ha, whereas 300 wind turbines take up for the land space, because the base of the tower is small. A nuclear plant takes up very little land area: 100 to 500 ha in the U.S.
The average nuclear plant is about 980 MW I think, and in 1999 the capacity factor was 88.5%, which is lower than I expected. In other words "actual" size is around 870 MW.
As for distance from population centers, so are hydroelectric dams whose power is distributed for hundreds of miles.
Major sources of hydroelectric power are much closer to heavily populated areas than major sources of wind. This is because large hydroelectric power dams are built on large rivers, and cities have always been built on large rivers. Typically, dams are built where there is a steep drop in the river, which was the end of the navigable water. Early 19th century settlements tended to be no more than 50 to 100 km below these steep drops, and by the latter part of the century railroad construction meant that large cities could be -- and were -- built nearby places like Niagara Falls. Areas with a great deal of wind, on the other hand, tend to be isolated because they are unpleasant to live in, with unproductive land. They are still the least populated areas of the United States, especially North and South Dakota.
In other words, it just happens that areas with falling water often attracts population and large cities, whereas concentrated high winds on land tend to drive people away. Offshore wind is a different story. Coastal cities have traditionally been built close to where trade winds are steady and strong, because up until 1860 all of our oceanic trade was powered by wind.
- Jed
