Mirrors, pods, printed panels: Solar innovation heats up
When it comes to solar energy, much of the emphasis of late has been on declining prices. And with good reason; the closer to cost parity with fossil fuels, the more likely solar adoption is to accelerate.
But in addition to all of the activity around solar business models and financing mechanisms, underlying solar technologies also remain a major point of interest. From streamlining manufacturing processes to decreasing environmental impacts or simply trying to make it easier to generate power from the sun, a slew of companies are in the business of solar innovation.
The hard part, as is so often the case when it comes to new technology, is making a solid business case and scaling new solutions.
Here's a glimpse of how three specific solar technologies aim to deploy renewable energy in inventive formats.
Mirroring the sun
Sweden-based Ripasso Energy already has 3 gigawatts of manufacturing capacity and is testing its solar concentrating mirrors in South Africa's Kalahari desert.
The system involves huge, 100-square-meter dishes that rotate automatically, accurately following the sun. They concentrate the sun on a small point in the center, which drives a zero-emissions Stirling Engine, reports The Guardian.
The mirrors convert 32 percent of the sun's energy into electricity — much more than the 21 percent converted by the most efficient solar panels. Yet the mirrors also take up much less land than other concentrating solutions and require no water at all.
One mirror generates 80 megawatt hours of electricity a year, enough to power an average 24 average homes, according to tests by IT Power.
The challenge, of course, is to get costs down and to get enough financing, and the mirrors can be used only in areas with strong sunshine.
ECO-GEN claims that its modular solar system brings the costs way down to generate clean electricity. All you need is four to eight solar panels and an 8-foot by 6-foot box called the JouleBox Hybrid Generator.
Each modular pod produces 60 kilowatts of continuous energy a year, rain or shine, by tethering the solar panels to an integrated turbine generator backup system. The boxes can be stacked and expanded to 50 megawatts (MW).
To generate 20 MW takes up less than 55,000 square feet, in contrast to a solar farm which would cover over 600 acres. Although the company eventually plans to make the pods for homeowners, ECO-GEN is starting with commercial applications.
Organic solar cells have been under development for years — flexible, cheap, portable and printable solar cells — and the first generation of the technology is getting close to commercialization.
After printing solar cells, larger cells can be attached to windows to produce electricity and smaller ones can be used to charge smartphones and laptop computers, for example.
The technology works by printing a fine layer of solar semiconductor "ink" onto plastic or steel to capture sunlight. Right now, the printed cells are only 10 percent as efficient as solar panels (although they are also much smaller).
Ink and plastic hardly cost anything, and silicon gets cheaper all the time. With these encouraging economics, the hope is that cheap, printed solar cells could end up in all sorts of applications — especially as they work well even when it's cloudy.
Australia's Victorian Organic Solar Cell Consortium has a goal to develop organic solar PV cells that can be printed commercially and get 10 percent efficiency for 10 years — an endeavor it has termed the 10plus10 challenge.
"Eventually we see these being laminated to windows that line skyscrapers. By printing directly to materials like steel, we'll also be able to embed cells onto roofing materials," David Jones, who coordinates the consortium, told Phys.org. They even could be attached to solar panels to boost their power.