98% of what?
On Twitter, I was sent to the headline Wind supplied 98% of Scotland’s household Power in 2014 and other Amazing Green Energy Stories.
That sounds pretty amazing. Nearly all of household electricity from wind. The next question, of course, is “And how much of the commercial and industrial electricity?”
What actually happened was that wind power supplied 40% of Scotland’s electricity last year. That’s still pretty good, but it doesn’t make such a great headline. Since household electricity was 41% of use, if you pretend that all the wind power went to households, you get 98% of household use.
The headline is misleading in the obvious way. It’s also misleading in a non-obvious way: one of the problems with wind power is that it’s generated when the wind blows, not on demand. If the power grid were set up so that household electricity was a thing, you couldn’t reasonably supply 98% of household power from wind alone.
The figure seems to come from WWF Scotland
Wind turbines provided an estimated 8,958,130MWh of electricity to the National Grid, or an average of 746,510MWh each month – enough to supply the electrical needs of 98% of Scottish households, or 2.36 million homes.
Most people who reported it didn’t go as far as the headline I quoted; on the other hand, most people didn’t pass on the data that lets you work out the real proportion.
Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »