Gonen Fink’s Pythagorean Theorem: a Skylight that Makes Electricity

Not many companies make a completely unique product, even in the world of green tech, which is all about innovation, but Israel’s Pythagoras Solar is one of them.

Here’s the idea. Imagine having a super energy-efficient skylight, that lets in all the sun that you need to fully daylight your store, warehouse or office space, so as to cut down on your electricity bill. Just the thermal efficiency alone would make it a good day-lighting option, blocking all direct solar radiation, to reduce building heating and cooling costs.

And now imagine that that seemingly clear and transparent skylight is actually a solar panel and it is also making your electricity, just like any other solar panel. That is the seemingly magic skylight by Pythagoras Solar.

Most so-called other BIPV or building-integrated photovoltaics is less efficient than traditional crystalline silicon solar. But Pythagoras uses technology from Chinese partner China Sunergy which provides extremely efficient monocrystalline silicon cells to make the impossible happen.

The skylight solar panel makes just as much power as a regular solar panel of the same size: 13 watts a square foot, and it is also ideal for use as a skylight because it also provides better day-lighting compared to a solar panel – being essentially transparent, limiting lighting costs by replacing fluorescent lighting, while looking like a regular skylight that provides real natural daylight.

Lets say you have a single story strip mall with stores that have a window at the front, but the spaces are long deep dark recesses. Now put say two ten foot square skylights in the middle, opening up the store to daylight.

At 13 watts per square foot, a couple of ten foot square Pythagoras skylights, amounting to 200 square feet would comprise a 2.6 KW solar system. On average this would produce around 500 kilowatt hours a month.

The magic of this remarkable double-duty skylight-cum-solar panel is achieved with optics on the surface that filter light to let daylight through, while mirrors reflect light onto solar cells. Typical commercial insulated glass units have two panes of glass, placed about one inch apart and held in a metal frame, which are coated with a film to block out heat from the sun.

CEO and co-founder Gonen Fink, with a B.Sc in computer science and physics and an MA in philosophy, is hardly new to radically useful innovations.

He was also VP of R&D of the internet security company that invented the computer firewall: Israel’s CheckPoint.

:: Pythagoras

Related BIPV solar stories:
People Who Live in Glass Houses Should Harvest Solar
Tel Aviv $60 Million Eco-Office Tower
Pythagoras Solar Unveils Solar Window

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