Xcel energy, which provides electricity and natural gas to Colorado, has apparently completed the bidding process for a solar power facility that will generate 8 megaWatts (800 kW) of solar power. The cost is $60 million. That works out to $750 for 100 Watts, or a little more than what I guesstimated earlier in estimating the cost of solar power facilities to provide all of the country’s electricity needs. First, it’s nice to see the back-of-the-envelope estimate come in within a factor of two of the real cost. More importantly, this is a real-world cost for a large-scale facility, including all the related infrastructure. Future similar installations, if voters elsewhere demand them, like Colorado voters did in 2004, will be cheaper as more solar cell manufacturing plants come on line in the next several years.