Jon Chase joins engineering students at Cambridge University hoping to win a race across Australia in their solar-powered car. Today they are testing the 110 km/h car on an airfield. They need as much power as possible, so the team uses solar cells normally used in space to power satellites. Jon discovers how the cells use light to make electricity. But solar power isn’t all about electricity. Plants are solar powered. And because we eat plants, this means most of us are solar-powered too. The substance in plants that captures light energy is called chlorophyll. Jon experiments with chlorophyll and finds out why green plants are green. Teacher notes: When learning about energy transfers, or when learning about light, this could be used to illustrate that light energy can be transferred to electrical and chemical energy. When teaching about photosynthesis, this can be used to consolidate understanding about what makes plants green and the role of chlorophyll in photosynthesis. Students learn how the green pigment in plants (chlorophyll) reflects certain colours of light from the visible spectrum and absorbs others. Pupils could discuss the statement: 'humans are solar-powered' and construct explanations, using their knowledge about food chains and food webs, and the interdependence of organisms in an ecosystem.