Energy plays a crucial role in today’s economy, and fossil fuels make up about 85% of the total energy consumption around the world. Global aggregate demand for energy is growing, even in the face of the undeniable impact of carbon dioxide emissions on the environment. Hence arises the need to shift to renewable energy sources in the coming decades, and therefore many exciting research possibilities. The talk will include a broad overview of the currently known techniques for (a) photovoltaic conversion of solar energy, and (b) the use of solar thermal energy, pointing out some possible research areas and typical applications. Sample calculations of cost will also be presented, on a per kilowatt-hour basis and also for an interesting small application.