Solar steam generator
Have you ever played in the sun with a magnifying glass? Even the smallest ones can burn wood, or set grass on fire.
So, why can't we build a manifying glass array, point that sun heat towards a steam turbine and produce electricity? Steam turbines are readily available as are the generators they drive. The major engineering would be setting up the glass array and building a solar tracking system to keep it aligned at the correct angle to the sun.
Reward: My reward would be a big smile knowing we are finally using something else besides oil, gas or nuclear.