Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Solar power, with a side of hot running water

New system for flat-panel solar power could be combined with hot water systems for greater performance.

MIT researchers and their collaborators have come up with an unusual, high performance and possibly less expensive way of turning the sun’s heat into electricity.

Their system, described in a paper published online in the journal Nature Materials on May 1, produces power with an efficiency roughly eight times higher than ever previously reported for a solar thermoelectric device — one that produces electricity from solar heat. It does so by generating and harnessing a temperature difference of about 200 degrees Celsius between the interior of the device and the ambient air.

The concept “is very radical,” says Gang Chen, MIT’s Carl Richard Soderberg Professor in Power Engineering and director of the Pappalardo Micro and Nano Engineering Laboratories, who co-authored the new paper with MIT doctoral student Daniel Kraemer and collaborators from Boston College and GMZ Energy. The work is funded by the Solid-State Solar-Thermal Energy Conversion Center, an Energy Frontier Research Center at the U.S. Department of Energy.

While solar thermal electricity systems aren’t a new idea, they typically involve vast arrays of movable mirrors that track the sun and focus its rays on a small area. The new approach uses flat, stationary panels similar to traditional solar panels, eliminating the need for tracking systems.

Like the silicon photovoltaic cells that produce electricity when struck by sunlight, Chen’s system is a solid-state device with no moving parts. A thermoelectric generator, placed inside a vacuum chamber made of glass, is covered with a black plate of copper that absorbs sunlight but does not re-radiate it as heat. The other side of the generator is in contact with ambient temperatures. Placed in the sun, the entire unit heats up quickly, even without facing the sun directly.

The device requires much less material than conventional photovoltaic panels, and could therefore be much less expensive to produce. It can also be integrated into solar hot water systems, allowing the expenses of the structure and installation to serve two functions at once. Such solar water heaters are rarely seen in the United States, but are already a highly successful mass-market product in China and Europe, where they provide households with hot water and in some cases space heating as well.

The materials used to build such solar thermoelectric generators, made through a nanostructured process, were developed jointly a few years ago in Chen’s lab at MIT and in co-author Zhifeng Ren’s lab at Boston College. Their teams have continued to work on improving these materials and integrating them into complete systems.

Chen points out that the U.S. Department of Energy has programs to develop thermoelectric systems, mostly geared toward harnessing waste heat from car and truck engines. He says that solar applications for such devices also can “have an important role to play” in reducing carbon emissions. “Hopefully we can prove that,” he adds.

Li Shi, associate professor of mechanical engineering at the University of Texas at Austin, says this approach to solar power is “very novel, simple, and easy for low-cost implementation.” The efficiency level they have demonstrated so far, at 4.6 percent, is “already quite impressive,” he says.

“With the use of other or new thermoelectric materials that can operate at a higher temperature,” Shi adds, “the efficiency may be improved further to be competitive with that for state-of-the-art amorphous silicon solar cells. This can potentially provide a different approach to realizing the $1-per-watt goal for solar-electricity conversion.”

The new system wouldn’t be a substitute for solar photovoltaics, Chen says, but offers “another way” of tapping into the enormous amount of solar energy that bathes the Earth every day. And because it can be piggybacked onto the existing solar hot-water industry, the thermoelectric device could be a relatively inexpensive addition, with “no subsidies required,” Chen suggests. “It can be a game-changing thing,” he says.

Caroline McCall | EurekAlert!
Further information:

More articles from Power and Electrical Engineering:

nachricht New method increases energy density in lithium batteries
24.10.2016 | Columbia University School of Engineering and Applied Science

nachricht 'Super yeast' has the power to improve economics of biofuels
18.10.2016 | University of Wisconsin-Madison

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

Im Focus: New Products - Highlights of COMPAMED 2016

COMPAMED has become the leading international marketplace for suppliers of medical manufacturing. The trade fair, which takes place every November and is co-located to MEDICA in Dusseldorf, has been steadily growing over the past years and shows that medical technology remains a rapidly growing market.

In 2016, the joint pavilion by the IVAM Microtechnology Network, the Product Market “High-tech for Medical Devices”, will be located in Hall 8a again and will...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Oasis of life in the ice-covered central Arctic

24.10.2016 | Earth Sciences

‘Farming’ bacteria to boost growth in the oceans

24.10.2016 | Life Sciences

Light-driven atomic rotations excite magnetic waves

24.10.2016 | Physics and Astronomy

More VideoLinks >>>