North by Northwest

Photovoltaic Moore’s Law Will Make Solar Competitive by 2015

Now there are some new twists and turns—essentially, three very positive developments that would not have been generally anticipated a decade ago. First, silicon-based solar technology has decoupled from the semiconductor industry and is achieving steady cost reductions, so that those following PV discern a kind of Moore’s law at work. In 2005, production of silicon for solar cells already surpassed production of silicon for semiconductors.

Second, the industry has become so confident in that evolutionary path, policymakers and planners have started to set dates when they expect PV-generated electricity to be competitive with the major sources of electricity sold on the grid now. And third, while the incremental path promises a commercial breakthrough within ten years, it’s suddenly looking like second generation technology may be arriving after all—in which case wide commercialization of PV could occur much sooner.

 
[Above, maps showing average daily solar energy]

In recent years, global PV production has been increasing at a rate of 50 percent per year, so that accumulated global capacity doubles about every 18 months. The PV Moore’s law states that with every doubling of capacity, PV costs come down by 20 percent. In 2004, installing PV cost about $7 per watt, compared to $1/W for wind, which at that time was beginning to stand on its own feet commercially, Last, year, as recently noted in this blog, average global solar costs had come down to between $4 and $5 per watt, right in line with the PV Moore’s law. Extrapolate those gains out six or seven years, and PV costs will be below $2/W, making photovolatics competitive with 2004 wind.