Power-up is one of a set of very simple games offered by the Nasa ‘Climate Kids’ microsite. There are two, overlapping, aims of the game: To shift a turbine up and down to catch the wind and a solar panel back and forth to avoid cloud and rain. The combination of these tasks offer a degree of gaming challenge as well as a nod to the compromises and complexities involved in building a usable energy mix. Warning: Addictive.