Satellites offer synoptic views of the physical phenomena of interest to renewable energies. Satellite images are routinely used to map solar radiation. Wave height over the whole ocean can be imaged, and maps can be constructed which may be helpful to assess the swell close to seashore. Scatterometers aboard satellite provide maps of wind speed offshore. Sea surface temperature is mapped from space for many decades. Using such maps and solar irradiation and wind speed as inputs to a model yields vertical profile of the temperature, from bottom to surface, helpful to assess the potentail of a OTEC system. Satellite data can be assimilated into numerical models. They can be fused with in situ measurements, e.g. buoys, to produce maps of greater accuracy, such as for sea surface temperature. They can be fused with other satellite data having different properties. For example, scatterometers and SARs both provide wind speed but with different spatial resolution and time scale. Wind statistics obtained from scatterometers far from the coast can be enhanced in spatial resolution and brought to the coast by a fusion with SAR images.