Solar Panels Using Nanotechnology

I have a state competition tommorrow and I need help on solar energy?
My question is what besides solar panels and zeolites can store solar energy?
Our project is about using nanotechnology to store solar energy. We are trying to think and look of something that may store solar energy and is much like chloroplasts (if possible).
Thank you
Well any green plant that is growing is storing solar energy. And you can release that energy by burning the plant.
Emerging Technologies: Green Nanotech & MEMS – AlwaysOn GoingGreen 2007