 So much positive energy and warmth, what if there were a way to save it all and use it when we want? Well there is, and we've been doing it since we discovered fire. Trees absorb and store the sun's energy by turning it into wood, which has always been the world's most used source of renewable energy. We don't just cook and heat our homes with it, new scientific advances using wood waste are opening it up to even more uses like liquid biofuels to power cars and aeroplanes, making it a fuel of the future. Using wood sustainably keeps a balance for future generations. The Forest. Nature's powerhouse.