Ask a consumer to think of solar power and chances are they’re going to imagine some panels on a roof, tilting toward the south.
Polysilicon has represented the most efficient way to create solar power for some years, and companies like Applied Materials were already scaled up to meet increased demand for what is, at its heart, chip-making technology.
A lot is still happening in the solar panel market. Sharp has begun mass production of new cells with a back contact structure and improved alignment. It estimates production for next year alone at the equivalent of 200 megawatts. Intevac just bought Solar Implant Technologies with an eye toward bringing SIT’s ion implant module to market in its LEAN SOLAR production system.
If we have standards for how big a panel should be, how it should fit on the roof, and how it should connect to the grid, we can have a great business. You can buy panels today and, when better panels come out in a few years, you can replace them easily.
But you don’t need panels.
For years now CIGS systems have been the main alternative to panels. CIGS efficiency is improving, and on a per-watt basis it should prove better than silicon soon. And it’s not the only thin film technology available. Konarka produces a thin, flexible plastic with an efficiency rating of “only” 8.3%, but the flexibility and low cost of what it calls “power plastic” give it many market advantages.
A lot of excitement remains in university labs, but some breakthroughs there are closer to market than you think. Iowa State researchers think they can improve the efficiency of thin films by 20% with a very thin substrate that adds texture and can capture twice the light of flat cells. This is a manufacturing technique, which could make thin films as efficient as silicon within a very short time.
Besides looking like a hard panel or a thin film on a wall, future solar panels could also look a lot like your cable dish.
Stanford researchers have an entirely new energy conversion process to offer, called photon enhanced thermionic emission (PETE). PETE coats a semiconductor with cesium to harvest both light and heat. Its efficiency peaks at well over the boiling point of water, and the heat can be re-used by other technologies, says Nick Melosh.
The theoretical efficiency of the process is 60%, which they hope to prove by replacing the gallium nitride semiconductor they had been using with gallium arsenide, which can take more heat.
All this is a problem for those now in the business. We can have standards for panels, and encourage short term sales based on regular replacements, but what if thin film proves better? What if PETE does?
The answer is to retain your imagination. Solar technology will come to the market as a film, as a paint, even as dishes. The key to success will be in doing the math for your customers, and playing straight with them.
It will lie in building relationships with them so you are trusted for repeat business. How much power can they generate, how durable is the solution they’re looking at, how long will it take for them to get back their investment, and what can you do for them then?
Wash, rinse, repeat.