Solar Power - Not Ready for Primetime

The growing awareness of America's total dependence upon fossil fuels in order to run its economy has focused tremendous attention on alternatives. Solar power has long been a contender for the mantle of oil's eventual successor. Indeed, given the almost total lack of downsides that other contenders like wind and nuclear power must struggle to surpass, solar power has long looked like a pretty safe bet.

Much has been made of solar's inability to provide power at night, or whenever the sun isn't shining. While solar power is clearly at a deficit compared to nuclear power here, the simple truth is that powerful, portable, and cheap batteries are a complete prerequisite for any transition away from the internal combustion engine in transportation.

And it is solar power's reliance upon battery technology to enable consumers to use electricity effectively that ensures solar power will not replace oil in any significant sense for at least a quarter century.

Solar panels have grown significantly more efficient over the last few decades, but they have achieved most of these gains by incorporating exotic materials and high-tech processing technology. While it is clear that many of these advances will eventually be available on materials cheap enough for mass consumption, the best value proposition in solar cells available today is on decidedly low tech variants. Two decade old technology does not approach the efficiency of the most up-to-date versions, but it has the chief advantage of being quite cheap. Because most solar panels can be expanded by two or three times without any real cost (due to roof space that is much larger than the most modern solar panels), using old solar panels to cover an entire roof is usually more economical than buying new solar panels.

The real trouble facing solar power is that battery technology has simply not kept up with the growth of other technologies. Lithium ion batteries attract a great deal of attention, but lead acid batteries - a hundred year old technology - remain at the forefront of the cost-benefit curve. And even if lead acid batteries somehow became twice as cheap, they are still subject to the fundamental weakness of modern battery technology - they become much less effective and store much less energy over time. In particular, batteries need to be drained completely and then recharged fully before their next use in order to maximize their lifespan. Since no real power system will allow its reserves to be completely drained at any time, all batteries connected to solar power sources will operate far below peak efficiency.

Another difficulty that holds solar power back is that solar power is usually considered a personal power solution. Since most homeowners that utilize solar power will have their own solar panels, they will need to face the entire cost of building their power supply up front. Even the so-called "grid-interface" systems that allow consumers to sell unused power back to the electric utility will be financed up front by consumers. If large corporations used solar panels to provide energy, they might use financial markets to achieve the ability to pay over time. Consumers, however, are unlikely to use financing to get solar power when the current system of lighting their homes requires no such investment. Ultimately, it doesn't make sense to take on another liability roughly equal to another car payment just to achieve energy self-sufficiency.

The trouble is compounded because solar energy doesn't scale up in a way that makes it attractive to large corporations. Each solar panel will produce power more or less independently of how many other panels are present in the grid. Since corporations should prefer energy sources that allow them to take advantage of their increased scale, an actual advantage is turned into a disadvantage. It is valuable to have a decentralized power grid, but not to the corporations that would like to control that grid.