Scientific American: Solar energy is touted by some as the solution to the world’s energy woes. But the process of making the various components requires fossil fuels, both for power and for the components themselves, some of which are based on petroleum. A new company, BioSolar, aims to kick petroleum to the curb, at least in the realm of building solar photovoltaics, cells of crystalline silicon that turn sunlight into electricity. Such photovoltaic cells rely on conventional plastic polymers to provide …