A research and development team at Wake Forest University has developed a device that is the first to generate power from both the Sun’s heat and its visible light. The team reports this advance in energy-efficient technology can potentially decrease energy costs by as much as 40 percent.
These polymer solar-thermal based cells constitute “a system that is ultra-efficient in home heating and cooling” according to David Carroll, Ph.D., Director of Nanotechnology and Molecular Materials at Wake Forest University, “Our solar-thermal device takes better advantage of the broad range of power delivered from the sun each day.”
Unlike geothermal add-ons for heat pumps on the market today that collect heat from the air or the ground, this new device relies on a fluid that flows through a roof-mounted module, where it collects the Sun’s while an integrated solar cell generates electricity from the Sun’s visible light, reports BioScholar.
The development team states that the design of the new solar-thermal device uses heat captured from an integrated array of clear tubes that are five millimeters in diameter. The tubes lie flat, where a proprietary blend of oil and dye flows through them.
The visible sunlight shines into the clear tube and the oil inside, and is converted to electricity by a spray-on polymer photovoltaic on the back of the tubes. As a result, the oil is superheated, and can then flow into a heat pump to transfer the heat inside a home.
In comparison to flat solar cells, the tube design has an important advantage of capturing light at oblique angles, meaning it can draw power for a longer period of time during the day. The Wake Forest team hopes that such a device can potentially be integrated into building materials, such as roofing tiles.
A standard rooftop can miss as much as 75 percent of Sun’s energy because it cannot capture the longest wavelengths of the light.
Tests thus far have shown 30 percent conversion of solar energy to power whereas standard solar panels convert only up to about eight percent on average. In coming months, the Wake Forest research team will produce a 3’ x 3’ square solar thermal cell as it plans to bring its technology closer to the marketplace.