Nick Palmer <ni...@wynterwood.co.uk> wrote: Not a perfect reply to the above, but it gives some idea... > > > > http://fullfact.org/factchecks/wind_turbines_performance_capacity_muir_trust_express_daily_mail-2646
That is an interesting article, worth reading. Their average actual values are: Onshore wind % capacity 2005, 28.1% 2006, 26.7 2007, 27.3 2008, 29.4 2009, 26.9 That is somewhat lower than you get at a prime U.S. onshore area such as the Dakotas or Texas. The article explains that they need to upgrade the power distribution network, and some of the power is going to waste now. The 2009 figure is abnormally low but it probably has to do with ongoing construction; i.e. units added to total capacity midway through the year. Nowadays, before they erect towers, they do comprehensive, 1 or 2-year studies with a small temporary tower equipped with anemometers and other weather forecasting equipment, so they know beforehand what to expect. The original article claims there was a turbine that produced only 15% of nameplate. Either it was out of service, badly sited, or that was a remarkable weather anomaly. If it was an anomaly, I suppose that since the wind has to blow somewhere, another turbine may have intercepted most of the wind and performed above average. Wind is a function of solar radiation and that has not changed, so I doubt overall wind or the patterns of wind have changed, or can change. Many conventional generators do not perform up to the expected fraction of nameplate performance for one reason or another, such as having the roof blown sky-high from a hydrogen explosion. As this article says, no one expects wind turbines to produce nameplate power on average. The original article was wrong about that. Probably, the author was dissembling. Regarding conventional alternative energy, here is an interesting article about a factory in Japan that produces nearly 1 GW (nameplate) in solar PV per year: http://www.renewableenergyworld.com/rea/news/article/2011/04/solar-frontier-opens-largest-thin-film-plant-in-the-world PV also produces roughly 30% of nameplate because the sun shines with peak intensity around 8 hours per day. However, unlike wind power, PV produces peak electricity at exactly the moment when demand peaks during the summer, because air conditioning kicks in when the sun is hottest. - Jed
