by Robert X. Cringely
Photovoltaic solar cells have been part of renewable energy planning for as long as such planning has existed, with most of those solar cells made from crystalline silicon with energy conversion efficiencies above 20 percent. But crystalline cells are expensive and take a lot of energy to create, reducing their net energy contribution. Fortunately there are other types of solar cells including thin film, amorphous, plastic, and others. All of these are cheaper than crystalline cells though they also tend to have shorter working lives and lower efficiencies. We care about them, though, because organic plastic solar cells in particular offer the prospect of producing the cheapest electric power of all. That is if one of our Startup Tour companies — Solarmer Energy Inc. — meets its design goals. I think they will.
Solarmer is effectively a Chinese company operating in America. Located in Baldwin Park, CA, Solarmer’s management is entirely from Taiwan, though many U. S. nationals are employed at the company. Solarmer is well funded, has been operating for several years now, and is moving relentlessly toward the goal of creating very large plastic solar cells that are 10 percent efficient, have a 10-year service life, and can be manufactured for $0.50 per watt or less.
Crystalline solar cells last for 25 years or more, but plastic or polymer solar cells have traditionally operated for only 2-3 years. Through the use of special UV-resistant coatings, Solarmer is attacking this longevity issue, though since the cost of plastic cells is so much less than silicon, 10 years is good enough.
Solarmer is steadily pushing cell efficiency, too, with their current world record in excess of eight percent efficient. Their goal is 10 percent and I believe they will make it.
Solarmer’s target of $0.50 per watt is based on low material cost and especially on low cost of production. The capital cost for producing Solarmer plastic cells is almost nothing as you’ll read below.
Plastic solar cells are made with a roll-to-roll printing process that starts with a clear plastic substrate on which multiple photo-sensitive semiconducting layers are printed, followed by a clear coat. Solarmer has a pilot printing plant operating in a clean room at its facility, though the world record cells have to this point been mainly built by hand.
Solarmer didn’t invent plastic solar cells, nor are they the only manufacturer. Another company — Konarka Technologies Inc. — is already producing such cells that can be found in many products. Both companies make flexible plastic solar cells, but there is a significant difference in their manufacturing strategies that made one company more interesting to me than the other (both were nominated for the Startup Tour).
Konarka builds its plastic solar cells in a 250,000 square foot former Polaroid photographic film plant in New Bedford, MA. With total control of its own production Konarka is already selling product where Solarmer is not. Unlike Konarka’s Big Factory strategy, Solarmer says it intends to license its technology to commercial printers. The difference between printing Parade magazine for your Sunday paper or printing hundreds of thousands of plastic solar cells per day is the addition of an extra drying stage at the output end of the web printer.
That’s why Solarmer quietly works-away, relentlessly pushing its technology to produce a little more power for a lot less cost. Once the specs are where the company wants them to be, their process will be released to a magazine publishing industry that has been slowly dying, killed by a combination of economic recession and Internet publishing. Hundreds of web printers originally costing tens of millions each will be repurposed for inexpensive energy production at that target $0.50 per watt — not just grid-parity but a quarter the cost of power from coal.
Flexible plastic solar cells will go everywhere the sun shines, produced in long rolls, covering roofs and even windows (the cells can be made transparent). Efficiencies are lower, sure, but so will be the cost. Any structure can produce at least some of its own energy. And though the plastic cells will have only a 10-year life, that’s longer than a paint job lasts in Charleston.
It’s a strategy of ubiquitous good-enough solar power that I find very compelling as part of our energy future.