Solar optimists are easily impressed

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I wrote a month ago about the strange claims from Chris Nelder that solar power could easily reach 10% of global electricity supply by 2020. Here he was:

Energy analyst Gregor Macdonald’s analysis of BP data shows that solar power consumption has grown at a compound annual growth rate of 63.2 percent over the past five years. He believes it should be able to maintain that rate as its rapidly falling costs and simplicity of deployment undercut alternatives. If so, solar would provide more than 10 percent of global electricity demand by 2020, surpassing nuclear generation, even while global power consumption grows by 3.4 percent per year.

This obviously impossible claim has since been repeated by Nelder, so I presume he thinks it is a serious forecast. So I was very surprised today to see him describe as “bullish” the latest IEA projections of solar growth in the next 6 years. According to the piece over at GreenTechMedia:

Total renewable capacity is expected to grow from 1,580 gigawatts in 2012 to 2,350 GW in 2018, while renewable electricity generation grows from 4,860 terawatt-hours to 6,850 terawatt-hours. Renewable generation will be 50 percent greater over the six-year forecast period than it was over the six years from 2006 to 2012.

It’s a remarkably bullish outlook compared to most forecasts. It’s particularly remarkable for the IEA, whose conservative outlook on renewables has historically lagged behind reality.

Global solar PV capacity will triple to 308 gigawatts, with 57 percent of new capacity being built in the OECD.

So, an IEA forecast of solar PV tripling in six years is “remarkably bullish” compared to most forecasts. But how exactly does it compare with the forecast of MacDonald? Not particularly well. In fact MacDonald seems to believe that total solar capacity will be more than six times higher in 2018 than the IEA does. Instead of bullish, Nelder surely should be calling this bearish. But this kind of incoherence is now to expected by those who buy into the narrative that the solar revolution is unstoppable. And while I am no fan of forecasts, this IEA one certainly implies that solar power is now off the exponential growth curve, if it was ever on it.

Hyped up claims aside, the realities of the growth of renewables is much more sobering than many of its advocates imply. A topic I will cover in more depth in an upcoming post.