Lucas123 writes: Even with today's inefficient wafer-based crystalline silicon photovoltaics, terawatt-scale solar power systems are coming down the pike, according to a 356-page report from MIT on the future of solar energy. Solar electricity generation is one of "very few low-carbon energy technologies" with the potential to grow to very large scale, the study states. In fact, solar resources dwarf current and projected future electricity demand. The report, however, also called out a lack of funds for R&D on newer solar technology, such as thin-film wafers that may be able to achieve lower costs in the long run. Even more pressing than the technology are state and federal policies that squelch solar deployment. For example, government subsidies to solar are dwarfed by subsidies to other energy sources, and trade policies have restricted PV module and other commodity product imports in order to aid domestic industry. Additionally, even though PV module and inverter costs are essentially identical in the United States and Germany, total U.S.residential system costs are substantially above those in Germany.