The solar power industry is going through a tremendous burst of creativity and innovation as more people switch to solar energy instead of energy generated by fossil fuel-burning power plants.
The latest generation of solar photovoltaic (PV) cells is far more efficient than their predecessors. Many are thinner or blend into a roof better. In addition, forward thinking people determined to harness the sun’s energy in exciting new ways are developing other types of solar power systems.
The first solar cells were developed more than 60 years ago. But the technology has caught on more in recent years, which is prompting further innovation. Here are some major milestones in solar panel history along with some of the newest types of solar panels that are either on the market or being developed for the future.
Innovations to convert more sunlight to energy
Silicon is reflective. As a result, solar panels do not absorb most of the light that hits them and they send the light particles back out into the atmosphere. Adding an anti-reflective coating helps a little, but not enough. Most of today’s solar PV panels convert up to 23 percent of the sunlight that reaches them into electricity. (This is better than the 10 percent achieved in the 1960s, but far short of ideal.) So, researchers have been looking for a solution to boost the efficiency of solar PV panels.
One solution could come from an unexpected source: moths. Moths have eyes with textured patterns. When light hits their eyes, far more is absorbed so they can see better at night. The texture cuts reflective glare too, so moths’ eyes do not glimmer and draw predators. Attempts to mimic moth eyes have improved glare on TV screens and are now being tested for solar panels. Scientists have begun creating tiny patterns in the silicon on the solar cell using a reactive gas plasma. The chip industry commonly uses this approach on electronic circuits. The results are promising and seem to improve performance of the solar panels by as much as 20 percent.
Ripasso Energy, a Swedish firm, has developed a different approach that they report converts 34 percent of the sun’s energy that hits their innovative device into electricity. Scientists at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) used a PV device to convert 40.8 percent of the light that hit it into electricity. While it was not achieved easily, the test shows that future innovations in solar panels will be more efficient in trapping the sun’s rays. But that’s no reason to not go solar today.
Alternatives to the traditional big solar panels
New Powerhouse “solar shingles” made by Dow integrate solar cells into roofing shingles to improve the aesthetics for those who don’t like the look of large solar panels. This allows homeowners to install a new roof and a new solar energy system as one project, since the solar shingles are applied like conventional shingles. The Dow shingles are now on the market in some states, but not all.
There are other types of what are called “building integrated photovoltaics,” including wall systems for office buildings and creative building designs using the panels. One building incorporated solar panels in a giant circle built into the architecture, while another used them as a curtain wall. Another building used the solar shingles in a dramatic, eye-catching pattern rather than a solid row. Solar cells have also been built into skylights or, at the California Academy of Science Museum, a solar glass canopy around the perimeter of the building that can generate 130 kW.
Other companies are trying to reduce the PV surface area that they use. One way they are investigating is to use concentrators to direct sunlight to smaller, more efficient solar panels. Toward that end, one company is testing inflatable solar collectors, aka balloons. The balloons would be approximately 400 times cheaper than an energy concentrator made out of polished aluminum, and they can be mounted on wires, reducing costs further.
Thin film solar panels
Demand for silicon has grown with all the electronic gadgets and mobile devices people use. So, faced with a shortage of silicon, several companies have been working on thin new solar panels. The NREL has created thin film solar panels that are not quite as efficient as the silicon-based versions, but they are getting very close.
With so many innovations in the works, it could be tempting to take a wait and see attitude toward installing solar panels now. However, with the tax incentives currently available and savings in energy costs to be gained now, there is a strong argument against waiting.
RGS Energy has almost 40 years of experience in installing state-of-the-art solar energy systems throughout the country. To find out how solar energy could power your home, visit www.rgsenergy.com.