What's the best way to generate more power? There are a lot of options for a county or state to consider when increasing their power generation: coal, gas, nuclear, solar, or wind, to name a few. But which to choose? There are many different factors to consider when choosing a new power source, but perhaps the best choice is the cheapest one. The University of Texas Austin's Energy Institute crunched the numbers and found the cheapest power plant to build in every county in the U.S. They compiled the data and created an interactive map for you to play with. Here's what that map looks like:On this map, natural gas plants, in orange and red, are the cheapest option for much of the south and west. Wind energy, in green, is very cheap in the Midwest and northeast, and solar, in purple and gray, is good for the southwest and some areas in the deep south. Nuclear, in blue, makes a few appearances near Lake Superior and the northwest. Since the map is interactive, you can change the costs of different power sources to see how that changes the situation. For instance, if a small carbon tax is applied, wind becomes the cheapest power source for most of the country while nuclear becomes the best option in many southern states. It's an open question whether any of that would actually happen, however this map is a useful tool for predicting the future of U.S. energy. If you want to play with the map yourself, you can do so here.