Spire Corp., a company involved in the design of solar cells and solar cell manufacturing equipment, has reported that it has successfully designed a solar concentrator cell with a 41 percent efficiency level, matching that of previous records. The design, which is a result of an ongoing contract with the National Renewable Energy Laboratory (NREL), is one more milestone that Spire has reached on its way towards its goal of a 42.5 percent efficiency level.
Commenting on the achievement was Roger G. Little, Chairman and CEO of Spire Corporation. “We have experienced continuous improvement in our proprietary cell processing design technology throughout the NREL contract. We are excited to have matched the current world record efficiency, and we have nearly four months remaining under the subcontract to surpass this level and achieve the target 42.5% efficiency. A more efficient concentrator solar cell will provide a lower cost and more reliable source of solar generated electricity.”
The solar concentrator cells are intended for use in concentrator photovoltaic solar systems. These systems traditionally have used large mirrors and optical lenses that concentrate sunlight at energy levels that are 500 or more times higher than natural sunlight. Because this concentrated sunlight is focused directly onto the solar cell, the amount of power that a solar cell can generate is proportional to the sunlight energy level in the concentrated sunbeam, often measured in terms of suns.
One of the main advantages that concentrator photovoltaic systems have over standard photovoltaic systems is that they require much less space. For example, if you concentrate sunlight at levels of 500 suns, you create a sunlight beam that has 500 times more energy per unit area than that of everyday sunlight. This means that with a solar concentrator system with 500 times sun magnification you could potentially design a solar cell system that is 500 times smaller.
Adding to the power generation capacity of concentrator systems are solar concentrator cells, like the one Spire has developed. These solar cells are miniaturized versions of concentrator photovoltaic systems, complete with the tiniest of lenses and mirrors. When these solar concentrator cells are used in concentrator photovoltaic system, the amount of sunlight per unit area can then be ratcheted up another order of magnitude, resulting in high-powered miniature solar energy systems.
Although solar concentrator cells are expected to eventually become commercially feasible, they will be much higher-priced than silicon solar cells. However, they potentially offer a faster return on investment than silicon solar cells and also have the potential to reduce the cost of generating solar kilowatt-hours to pennies, making solar cell technology far more cost effective than all other forms of energy.
