What if you needed a wrench and, when you tried to buy one, you found that they were all the same size? How many problems can be solved with a wrench of only one size? Eventually, you would have to find other ways to solve problems, and you would relegate the single-sized wrench to the class of projects that happened to be compatible.
Much the same is true of today's solar solutions: They come in one size (large, flat plate-glass modules) and are suited primarily to the task of capturing the sun in large open fields. But what about all the other places where energy is either unavailable or not cost-effective? Solving that problem requires wrenches of different sizes and even different shapes. The one-size mentality does not fit all problems, and in fact, a wide variety of alternative and embedded forms are required to really address the potential for solar energy to address the world's energy needs.
Let's look at the problem of needing electricity where it simply isn't available. Solar technology can be integrated into the wings of unmanned aerial vehicles for both military and civilian uses, increasing flight times dramatically. How about charging that cellphone and iPad we carry everywhere with us? Flexible sheets that can be right-sized to fit our portable devices could provide tens of watts of power everywhere we go. And no plug is required.
In the developing world, the need for energy is extreme. In fact, many researchers believe that economic and social prosperity starts by ensuring a ready and adequate supply of energy. The sun shines all day long -- why not build flexible charging mats that can provide kilowatts of energy in an area that's no bigger than a small patio? A 10x10-foot mat could be easily rolled up and stored but provide more than 2kW of energy generation capability when unfolded and exposed to the sun. Even a solar mat the size of a queen-sized sheet would provide 1kW.
In much of the developing world, the primary source of energy generation is either centralized coal power plants or decentralized diesel generators. Why not deploy hybrid diesel systems that use the sun to generate power during the day and only consume diesel at night? The problem of intermittency goes away completely, while the consumption of costly diesel fuel would plummet. The same technology can be deployed to our armed forces, where the cost of carrying extra fuel or batteries is often immeasurable.
Electric vehicles are another good example. The batteries of today's electric vehicles must be maintained at a specific temperature to maintain their maximum storage capacity and overall lifetime. What happens when an electric vehicle is left parked in the hot daytime sun? The cooling system for the battery system will be drawing energy from the same battery it's trying to cool. In some cases, this could result in a catastrophic discharging of the vehicle's battery, destroying the battery. Why not integrate some flexible solar film into the vehicle's roof to solve this problem? One technology that's almost ready for prime time offers thin, flexible solar film sheets that can be molded directly into the car's glass roofing material and could provide more than 500W.
The eventual solution needs to be thin and light and be able to convert a significant amount of the sun's energy into electricity. Glass-plate silicon-based solar panels are too rigid and heavy. Thin film technologies such as CIGS are inefficient. What's coming are superthin GaAs-based solar cells that can be integrated into other materials. Only then can we realize embedding power everywhere.
Rich Kapusta is vice president of marketing at Alta Devices.