The amount of solar radiation striking the earth over a 3 day period is equivalent to all the energy stored in all fossil fuels. To increase the harnessing of this versatile energy source ETP works with partner SISER – Scottish Institute for Solar Energy Research to develop technologies for the more diffuse light levels typical in northern climates as well as technologies for developing countries.
ETP expertise in solar energy
Thin-film PV cells are considerably thinner than regular silicon cells and, being flexible, have the potential to be applied to many different places from building tiles, bodies of electric cars and textiles and clothing. ETP is developing ways to integrate thin-film PV on textiles, develop cheaper/ quicker manufacturing processes and develop new, more efficient, light harvesting materials.
Excitonic and Hybrid PV
Excitonic PV cells harness the sun’s energy in a similar way to plants, using polymers or dye molecules to absorb light energy and create the electrical current. These soluble materials provide the potential to manufacture large area flexible devices at low cost using machinery from the printing industry. ETP is synthesising new dyes and polymers and incorporating them into new cells to increase efficiency.
Next Generation PV
Next generation PV cells have potential efficiencies greater than regular silicon solar cells because they will be able to absorb a greater proportion of the sun’s solar energy spectrum. ETP is investigating several different methods, such as up and down conversion to increase the light- harvesting ability of solar cells.
Low concentrating Solar Thermal uses flat plate or vacuum tube thermal collectors for hot water production for homes and businesses. High concentrating systems which use lenses or mirrors to concentrate the sun’s light are used for electricity generation e.g. using Stirling engines. Researchers in Scotland are investigating ways to increase the efficiency of all these systems.
Concentrating PV (CPV) involves the use of lenses and mirrors to focus and concentrate a large area of light directly onto the PV cells. This allows less PV material to be used, while still maintaining efficiency. ETP is developing new lenses and thermal management systems to increase the efficiency of CPV.
PV systems comprise three main parts: the PV panels which generate the electricity; the load which extracts and uses the power e.g a device, a home or the grid; and the BOS (balance of system) i.e. all the other components that allows the PV generated electricity to be applied by the load e.g. inverters, cables/wires, switches, charge controllers, support racks and mounts, etc. and batteries in the case of off-grid systems. ETP researchers are investigating ways to better integrate these parts so that the systems work more effectively and efficiently with reduced energy losses.
Building Integrated PV
Solar energy is the easiest form of renewable energy to integrate into the fabric of a building. Building Integrated PV provides a way of developing the widespread use of PV. Researchers in Scotland are investigating ways to reduce the barriers to PV integration; for example the development of PV windows and the creation of more aesthetically pleasing PV installations.