For decades now, wind turbines have been generating electricity more cheaply than most other (non-hydro) renewable energy technologies. In particular, wind has maintained a comfortable lead over...
Wind faces a nano-scale threat.
senior executives at the Accenture International Utility & Energy Conference in mid-April. “Emerging nanotechnology will accelerate progress in the cost of solar panels.”
Already nanotech R&D is turning out some mind-boggling PV products. A company called Nanosolar now is selling thin-film solar panels—which the DOE’s National Renewable Energy Laboratory certified as being more than 15 percent efficient—produced by nano-printers at a rate of 100 feet per minute. The company claims that when it reaches full production it will be producing PV panels for 60 cents a watt; that’s wholesale cost, not installed retail cost, which is more like $2.50 a watt. Nevertheless, it compares favorably to roughly 80 cents for a watt of wind power capacity.
At PV’s exponential pace of progress, Kurzweil says the tipping point, at which the cost-per-watt of output from PV becomes lower than the cost from oil and coal, will occur in about five years—sometime around 2015. And assuming nanotech and solar R&D continues following Moore’s Law, global solar energy production will continue doubling every two years. “We are less than 10 doublings from [PV being capable of meeting] 100 percent of the world’s energy needs,” Kurzweil said.
Such hyperbolic predictions might be hard to swallow, and in fact Kurzweil wasn’t saying PV will replace every other energy source. Indeed, he was careful to point out that no technologies advance in a vacuum, and other energy technologies will enjoy their share of improvements. In particular, he said electricity storage and fuel cell technologies are advancing at a logarithmic rate, in keeping with their IT-driven nanotech R&D.
For wind, however, those improvements seem likely to advance at a more incremental pace, which raises a key question. Will solar eventually render today’s big wind farms obsolete?
Once capital costs are fully absorbed, the answer comes down to operating cost. For both wind and solar, the fuel literally falls out of the sky, so electricity costs for wind and solar plants depend entirely on operations and maintenance. According to figures prepared by Navigant Consulting (see “ Green Job Realities ”), wind farms rank among the cheapest to operate of all energy sources, including fossil, nuclear and hydro. By contrast, solar PV facilities are among the most expensive to operate, given the need to continually clean utility-scale solar panels.
For some time, this difference likely will keep existing wind farms comfortably competitive with solar among the renewable options available to the industry. But that could change too, given the relentlessly doubling nature of nanotech-driven PV. Spray-on materials, such as those described in a New Energy Technologies patent application, might need cleaning no more frequently than the windows to which they’re applied. And technologies like nanowires and quantum dots could embed PV cells into a range of products, including fabrics, paints and shingles. Such cells would have a low energy conversion rate, but so what?
If the cells are cheap enough, and the O&M costs are low (or even zero), PV becomes a game changer—challenging not only the industry’s traditional energy sources, but also the reigning green champion, utility-scale