In 2009 the US EIA expected 319 GW of wind power plants worldwide by 2020. The outcome: 733 GW
world wind capacity, GW
2.3 times more. The level the projection expected by 2030 was passed in 2017. Later projections raised the bar and still lagged.
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The US Energy Information Administration published the International Energy Outlook. Its reference case assumes current laws and technologies: a calculation, not a promise, yet investments were planned on it.
The solid line: the outcome in EIA statistics. Dashed: projections of different editions, the one in the text highlighted.
- 2009 outlook for 2020
319 GW
- Actual 2020
733 GW
- 2009 outlook for 2030
490 GW
Reference case of the International Energy Outlook editions 2009, 2010, 2011, 2013, 2016; outcome: EIA international statistics (INTL bulk file). Solar: photovoltaic and concentrating plants together.
Energy projections missed both ways: solar and wind grew much faster, nuclear and coal in older projections slower. A scenario is not a forecast, as the authors themselves say, yet it is used as one.
A question for this picture
Why did the projection extend past growth again and again, not its acceleration?