Usually, heat and light cannot be separated, because heat is a also a form of energy that we can’t ignore. Weidlinger Associates, a NY-based company, received a $150,000 grant this week to develop better, more durable hybrid solar roof panels. Hybrid means that they will incorporate both photovoltaic and thermoelectric materials to supply electricity and hot water for buildings.
Columbia University is also collaborating with Weidlinger on the hybrid solar project, hoping that they will convert at least 12% of the incident sunlight into electricity. More expensive, state-of-the-art solar cells reached 41.6% efficiency, but their cost doesn’t cover the benefits, so they won’t be adopted into mainstream usage very soon.
Protoypes of the hybrid thermal solar panels have been built. Their structure comprises a clear protective layer, then the photovoltaic cells, and then the hybridization: a layer of thermoelectric materials, saving the last part of the energy that can be converted into electricity, and they a layer of plastic tubes that carry water, cooling all the other layers. A last layer is a reinforcing plastic, making the entire contraption more durable.
Photovoltaic cells normally do their best up to a certain temperature, above which they inevitably become ineffective, so cooling them with water is increasing their lifetime and efficiency and heating water at the same time.
In addition to being tested in Columbia’s lab, a number of these panels will be installed atop a 6.4-square meter shelter located on the roof of the Frederick Douglass Academy, a New York City high school that specializes in the education of disadvantaged and underrepresented educational groups. Once the shelter is built, students will monitor the performance of the panels. “What we have to do is demonstrate a general commercial viability,” says Huiming Yin the designer behind the hybrid solar panels, adding that this means getting both the technology and its associated costs just right.
Price is a deciding factor after all, despite the efficiency being lower than that of high-end photovoltaic cells. Along with Dow Chemical, who is also making solar powered shingles, Weidlinger Associates is helping make this newer niche in construction materials affordable to more people than ever.