When it comes to the power that keeps our lights on, our food cold and our computers and TVs operating, we don’t want to consider the what ifs: What if the power goes out? What if supply can’t keep up with demand?

“We all know that once you go into what ifs, it’s a big set of what ifs,” says Mihai Anitescu of Argonne National Laboratory. And uncertainties only multiply as utilities add renewable energy sources such as wind to an already enormous and complex power grid. Each wind turbine increases variability in the power supply. Utilities must address new questions like, What if wind energy suddenly increases in the Chicago area but drops off around St. Louis? What if we count on wind energy but it doesn’t come through?