Renewable Energy Sources for Electricity Generation (2012)

The use of conventional energy sources for electricity generation, such as fossil fuel combustion and nuclear power, is questioned because of environmental and safety issues and concerns about possible anthropogenic climate change. This has led to rapid developments in the field of renewable energy exploitation. Entire new fast-growing industries are formed to supply equipment for renewable power plants. The contribution from Swedish industry to this development has so far largely been limited to providing parts and components and in most cases no integrated power plants are offered. From a Swedish perspective an important question is therefore what measures are needed in terms of research and development to increase Swedish participation in the industries related to renewable power plants. Three renewable primary energy sources have been investigated with respect to their energy supply potential, the industries involved, the technical state-of-the-art and finally the state of academic research. These are wind power, PV solar power and geothermal power. Currently, wind power has by far the largest installed base worldwide of these (238 GW) and also has the lowest levelised cost of electricity (LCOE) with credible figures of 7 c€/kWh presented for onshore installations. PV solar power is second in terms of installed power at 67.3 GW but shows faster growth, thanks to rapidly decreasing cost of equipment. The LCOE figures are approaching those of wind power (10 c€/kWh for Southern Europe is recently reported), which should allow for further growth. Geothermal energy production has been exploited for decades, and the installed base has reached 10.7 GW. It shows attractive electricity cost figures thanks to high capacity factor. LCOE is highly dependent on the location, but figures in the range of 4 c€-11c€ have been reported, which implies a significant potential. In terms of installations in Sweden, wind power is by far the dominant of the studied sources, with the remaining two being of marginal significance currently. Regarding academic research to increase the industrial base within renewables in Sweden the following recommendations are given. For wind power this goal can be achieved by promoting research into generator, transformer, and power electronic converter concepts, in close cooperation with established or newly founded companies. As for PV solar power, likely the main potential for Swedish industry lies in seeking further openings in the field of balance-of-system (BOS) equipment, considering the extreme price pressure on PV cells and modules, which has effectively forced several Swedish PV module manufacturers out of business. Academic research should thus focus on BOS aspects, with the aim of reducing LCOE. Finally, for geothermal electricity generation careful monitoring of the area should be encouraged, both technically and in terms of business. This should allow for the identification of suitable areas for research. A particularly interesting aspect that applies to several kinds of renewable energy sources, due to their temporal and spatial variability, is the use of long-distance power transmission, especially high-voltage direct current (HVDC). This is a Swedish strength area with world-leading companies. Therefore, academic research should also focus on the connection of different types of large renewable energy plants to HVDC transmission links.