Looking for signs that renewable energy is gaining real traction? We present IKEA.

Back in the day, every single solar installation from the purveyor of cheap and cheerful home furnishings was news. Now, IKEA solarizing a store is as common as, well, a birch veneer bookshelf. That’s got to be a sign of progress.

Already this month, the retailer has unveiled solar power arrays in Florida, Virginia, Texas, Michiganand, most recently, Pennsylvania. That flourish of installations brings the company’s U.S. total to 22 completed solar projects. (Update: Make that 23. A few hours after this story went up, Ikea announced the completion of another system, just over 1 megawatt, in Georgia.)

But what really demands emphasis here – it’s