Why Dr Evans is wrong

Simon Evans of Carbon Brief is known as the man behind the ludicrous claim that wind power is nine times cheaper than gas, a farrago of disinformation that is debunked in short order here. (Short version – he took gas-fired prices at the top of the market, messed up by taking them in Euros rather than in sterling, and then compared to preposterous figures for wind costs).

Today Dr Evans has declared that Michael Kelly has got it all wrong on electricity storage in an article in the Telegraph today. Unfortunately, this set of arguments is no less ludicrous than the last.

His beef is twofold. Firstly, he says indignantly that the Royal Society has said we can get all our energy from wind and solar. But this is to refute a case that Professor Kelly didn’t make; he restricted his remarks to saying, in effect, that a renewables/storage grid would be very expensive.

And it is the costs that are at the centre of Dr Evans’ other beef:

“[Kelly] claims building wind/solar/storage electricity system would entail costs equivalent to HS2 (let's say ~£100bn) "every year, forever" Right: Royal Society actually says it'd cost £410bn *in total*, which is…not the same thing. Oops!”

It’s hard to know where to start with this. Firstly, as David Turver has noted, the Royal Society figures are based on assumptions that vary between extremely optimistic, and incorrect:

• Demand will be 570TWh, around a third of what it is today (!)
• That demand will not change with weather conditions (!).
• The cost of everything on the system will fall through the floor compared to where it is today (!)
• The efficiency of everything will soar (!)

In other words, much of it could be characterised as “educated speculation”, and in the case of the fixed demand assumption it's simply not going to give you a correct answer. Even just allow that demand to flex with temperature, you are going to need vastly more generation capacity, a bigger store, and more power stations to turn the hydrogen back into electricity. And if you don’t assume, say, that offshore wind will suddenly deliver 63% of capacity, and stick with 40% (where the fleet average has been stuck for 10 years or so), then you will need huge amounts more.

As for the idea that the costs will be “forever”, well yes. Wind turbines (and the rest of it) wear out and need to be replaced. Dr Evans seems to think that they will not - a schoolboy error, if ever I saw one. This is not hard to grasp. If you start installing all those hundreds of gigawatts of wind turbines now, any you do next year will be worn out before 2050 (assuming a 25 year lifespan). Any you install in 2026 will need to be replaced in 2051. So the cost is ongoing. (Note this also means that we need the output of wind turbines to increase from 40% to 63% in two years' time).

The figure of £410 billion that Dr Evans quotes looks fine, if you use the Royal Society's assumptions. Let's call it £16 billion per year. But that's just the capex. You'll have nearly the same again for opex, and probably (optimistically) another £10 billion for cost of capital. So that's £40 billion per year, which is not far short of where HS2 started out (once you adjust to current prices).

But again, that's only if you use the Royal Society's assumptions. The true cost will undoubtedly be much bigger.

I say again, Dr Evans' points are ridiculous.