Reply #12: Actually, 700 MW of solar is ~200 MW of real-world energy

[NickB79]

Solar energy has a 20-30% loading efficiency when you consider clouds and nighttime, as per calculations performed by NNadir on the Environmental board here at DU. 700 MW is how much power the solar panels produce at peak operating hours, not averaged out over the entire day.

So, Germany would have to triple their current solar energy production to equal one coal or nuke plant. This wouldn't remove the coal or nuclear plant from operation, though, because comparing solar and wind to coal and nuclear are like apples and oranges. Solar and wind compete with natural gas-fired plants, because they are PEAK LOAD operators. Nuclear and coal are BASE-LOAD operators. Building more solar panels or wind turbines remove natural-gas-fired plants from operation, not coal or nuclear plants. Without massive battery back-ups, wind and solar can't be considered base-load power sources.

NNadir summarized it better than I ever could here: http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=115x58005#58104, especially with regards to wind power in Europe in post #19.

"...Despite their being cited as the shining example of what can be accomplished with wind power, the Danish government has canceled plans for three offshore wind farms planned for 2008 and has scheduled the withdrawal of subsidies from existing sites. Development of onshore wind plants in Denmark has effectively stopped. Because Danish companies dominate the wind industry, however, the government is under pressure to continue their support. Spain began withdrawing subsidies in 2002. Germany reduced the tax breaks to wind power, and domestic construction drastically slowed in 2004. Switzerland also is cutting subsidies as too expensive for the lack of significant benefit. The Netherlands decommissioned 90 turbines in 2004. Many Japanese utilities severely limit the amount of wind-generated power they buy, because of the instability they cause. For the same reason, Ireland in December 2003 halted all new wind-power connections to the national grid. In early 2005, they were considering ending state support. In 2005, Spanish utilities began refusing new wind power connections. In 2004, Australia reduced the level of renewable energy that utilities are required to buy, dramatically slowing wind-project applications. On August 31, 2004, Bloomberg News reported that "the unstable flow of wind power in their networks" has forced German utilities to buy more expensive energy, requiring them to raise prices for the consumer.

A German Energy Agency study released in February 2005 after some delay stated that increasing the amount of wind power would increase consumer costs 3.7 times and that the theoretical reduction of greenhouse gas emissions could be achieved much more cheaply by simply installing filters on existing fossil-fuel plants. A similar conclusion was made by the Irish grid manager in a study released in February 2004 : "The cost of CO2 abatement arising from using large levels of wind energy penetration appears high relative to other alternatives.""