Xcel’s biggest coal plant will be retired in 2069. Xcel says that we will have over 1800 MW of coal plants for the foreseeable future – 50% coal in 2020. Xcel says that in 2020, even with their renewable plans, we will see only a 28% reduction in greenhouse gas emissions. Xcel also says that even at today’s 11% renewables, coal fired power plants force wind farms to be turned off (“curtailed”) even when the wind is blowing so Xcel can burn coal. So Xcel customers pay for both the coal electricity and the “turned-off” wind – $3.8 million in 2010 – costs that have skyrocketed up thirty times since 2007.
Using natural gas generation to complement renewables and fill in their intermittency is not new and is similar to how Xcel is integrating wind on top of their baseload generation from coal. Gas turbines can be turned down or off and restarted within minutes, therefore they provide a more flexible basis for integrating renewables versus the status quo utility baseload coal or nuclear power.