Joe Romm for ThinkProgress:  Remarkable drops in the cost of solar and wind power have effectively turned the global power market upside down in recent years.

We’ve seen prices for new solar farms below 3 cents per kilowatt hour (kwh) in other countries for over a year now, but before this week, not in the U.S. That changed on Monday when Tucson Electric Power (TEP), an Arizona utility company, announced that it had reached an agreement to buy solar power at the same game-changing price.

TEP says that this is a “historically low price” for a 100-megawatt system capable of powering 21,000 homes — and that the sub-3-cents price is “less than half as much as it agreed to pay under similar contracts in recent years.”  Full article: