Solar Energy Collection and Conversion
Harnessing the power of the sun is critical to meeting the world’s energy demands. A multitude of different technologies exist to convert solar energy into electric power or heat. Some popular technologies include solar water heaters, concentrated photovoltaics, and heat engine based systems. All of these solar applications require appropriate thermal management in order to maintain performance and cost goals. Advanced Cooling Technologies, Inc. (ACT) has technologies developed to aid in the thermal management of all of these solar applications.
Examples of ACT’s thermal management products and technologies for solar energy collection and conversion applications include:
- Concentrated Photovoltaics (CPV)
- Solar Water Heaters
- Solar Stirling Heat Engines
In CPV applications, solar energy is concentrated on a small area such that the radiative flux on the photovoltaic cell is increased. This allows CPV engineers to replace the large silicon solar cells used in traditional solar panels with a smaller piece of high performance material while maintaining a similar cost. However, the increased performance can only be maintained if the temperature of the solar cell can be maintained near ambient. This is difficult, as the concentration of the solar radiation also results in a concentration of waste heat that needs to be dissipated. ACT has experiences in designing heat pipe heat sinks to spread the heat from the solar cell and dissipate the heat through finned heat sinks. The benefit of this solution is that there are no moving parts, resulting in the high reliability typical of traditional solar panels.
Converting solar energy directly to heat is a very efficient way to heat space and water supplies in residential homes and commercial buildings, and fluids in industrial processes. Solar troughs with heat pipes are a popular solution to collect the concentrated heat and transfer the heat to a pumped recirculation stream. Commodity solar water heat pipes are limited in their maximum operating temperatures, typically in the range of 80°C to 120°C. This limit prevents the solar heating system from achieving higher efficiencies. ACT has a line of intermediate temperature heat pipes that can expand the solar heating system’s operating temperature beyond 250°C for increased heating efficiency.
Heat engines, such as Stirling engines, thermoacoustic generators, and thermionic converters, are often used to generate electricity from solar energy. In these processes, solar energy is concentrated onto a solar receiver which absorbs the solar energy as heat. The receiver temperature must be in excess of 400°C for the heat engine to be effective. Typically temperatures above 800°C are targeted in order to attain desired solar to electric conversion efficiencies. ACT’s high temperature heat pipes are an effective method of acquiring the high temperature heat from the receiver and transferring the heat isothermally to the hot side of the heat engine with minimal losses.
Whether it’s CPV, solar water heating, or a heat engine, ACT’s team of thermal experts has the broad experience and technology portfolio available to help solve your solar thermal problem.