A conceptual energy storage system design that utilizes ultra high temperature phase change materials is\ud presented. In this system, the energy is stored in the form of latent heat and converted to electricity upon\ud demand by TPV (thermophotovoltaic) cells. Silicon is considered in this study as PCM (phase change\ud material) due to its extremely high latent heat (1800 J/g or 500 Wh/kg), melting point (1410 C), thermal\ud conductivity (~25 W/mK), low cost (less than $2/kg or $4/kWh) and abundance on earth. The proposed\ud system enables an enormous thermal energy storage density of ~1 MWh/m3, which is 10e20 times\ud higher than that of lead-acid batteries, 2e6 times than that of Li-ion batteries and 5e10 times than that\ud of the current state of the art LHTES systems utilized in CSP (concentrated solar power) applications. The\ud discharge efficiency of the system is ultimately determined by the TPV converter, which theoretically can\ud exceed 50%. However, realistic discharge efficiencies utilizing single junction TPV cells are in the range of\ud 20e45%, depending on the semiconductor bandgap and quality, and the photon recycling efficiency. This\ud concept has the potential to achieve output electric energy densities in the range of 200-450 kWhe/m3,\ud which is comparable to the best performing state of the art Lithium-ion batteries

Crystalline silicon solar module manufacturing cost is analysed, from feedstock to final product, regarding the equipment, labour, materials, yield losses and fixed cost contributions. Data provided by European industrial partners are used to describe a reference technology and to obtain its cost breakdown. The analysis of the main cost drivers allows to define new generation technologies suitable to reduce module cost towards the short‐term goal of 1 € per watt‐peak. This goal roughly corresponds with the cost level needed to enable ‘grid parity’: the situation solar electricity becomes competitive with retail electricity. The new technologies are described and their costs are analysed. Cost reductions due to scale effects in production are also assessed for next generation manufacturing plants with capacities in the range of several hundreds of megawatts to one gigawatt of module power per year, which are to come in the near future. The combined effects of technology development and economies of scale bring the direct manufacturing costs of wafer‐based crystalline silicon solar modules down into the range of 0·9–1·3 € per watt‐peak, according to current insights and information (the range results from differences between technologies as well as from uncertainties per technology). Copyright © 2008 John Wiley & Sons, Ltd.

Since its invention in the 1950s, semiconductor solar cell technology has evolved in great leaps and bounds. Solar power is now being considered as a serious leading contender for replacing fossil fuel based power generation. This article reviews the evolution and current state, and potential areas of near future research focus, of leading inorganic materials based solar cells, including bulk crystalline, amorphous thin-films, and nanomaterials based solar cells. Bulk crystalline silicon solar cells continue to dominate the solar power market, and continued efforts at device fabrication improvements, and device topology advancements are discussed. III-V compound semiconductor materials on c-Si for solar power generation are also reviewed. Developments in thin-film based solar cells are reviewed, with a focus on amorphous silicon, copper zinc tin sulfide, cadmium telluride, as well as nanostructured Cadmium telluride. Recent developments in the use of nano-materials for solar power generation, including silicon and gallium arsenide nanowires, are also reviewed