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Greenpeace UK tweeted about the UK having enough wind to power the country five times over:

MT @1010: The UK has enough wind to power the country five times over. Let's use it!

window power infographic

After a bit of Googling the only source for the data seems to be a wind energy company. That doesn't mean the data is false, but I'd like a more trustworthy source.

Does the UK really have a 2,000 TWH capacity for wind power as claimed?

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    I edited the question to focus on one of the claims made. No-one here seems to be claiming that wind can replace other sources - merely that it has the potential to provide more power than is currently used. (For example: There is enough wind on the ocean to drive many, many more sailboats than we have motorboats, but that doesn't mean sailboats can replace motorboats.) – Oddthinking Jul 26 '14 at 4:02
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TL:DR; Yes, the UK has potential wind resource to power itself many many times over. Yes, it could be five times as much (range: 4-200x). No, its technical potential harnessable wind resource is not 2000 TWh a year - it's much larger, but we don't know how much more; it's probably in the range 10,000 - 80,000 TWh/y.

For context, UK primary energy demand is of the order of 2500 TWh/y (Digest of UK Energy Statistics 2013, p14); final energy consumption is about 1630 TWh/y (ibid); electricity is currently around 376 TWh/y (ibid p113). So it depends which of those figures you take, and which of the estimates you use: the potential wind resource is somewhere between four and 200 times the size needed to power the country.

How much larger the potential wind resource is very unclear, because there's an enormous potential resource, but we don't know how much of it is technically accessible. There are several reasons for this.

  • we don't know how densely we can site floating turbines - they only exist as prototypes at the moment.

  • we don't know how deep the waters are that we can harvest wind in. Although much of the UK's Exclusive Economic Zone is in waters of less than 700 metres depth, there are extremely strong winds in deeper waters.

  • we don't know how big the inter-array wake losses are if deployment ever got to saturation density. (see the discussion in the section "The modelling methodology smackdown" in my answer here) Given the scale of the potential resource, we won't get to within 20% of saturation density for many decades.

Here's one estimate of the UK offshore wind potential, which estimates it at 2.2 TW of mean electrical output: with 8760 hours in the year, that's 20,000 TWh per year - more than ten times the number you've found. (graph is GW mean power - multiply by 8.76 to get the equivalent TWh/y for non-leap years). You might want to deduct 10% for shipping lanes, but that's just a guess at what the right % would be.

Graph of wind availability by depth of water

Stuart Gatley's M.Eng ("An investigation of the potential of offshore wind power in the UK, University of Nottingham, 2012) estimates the offshore resource as being in the range 10,862-79,978 TWh/y (p56)

That's the offshore resource, which dwarfs the onshore resource. "The UK onshore wind energy resource", ETSU R-99, F Brocklehurst, 1997, estimates the technical potential in the range 20-50GW mean power - that's 175 - 438 TWh/y. (that number is from memory: I don't have the report to hand; I'll verify that on Monday; but safe to say it gets lost in the rounding of the offshore wind resource)

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    I think the single most misleading aspect of the claim, which this answer does not address, is that a wind turbine only works when the wind is blowing. To actually use wind to produce all the power UK needs, you'd either need a storage technology that doesn't exist, or have the winds correspond to demand. You also seem to neglect transmission losses (which will be significant for deep water wind farms). – Gabe Jul 28 '14 at 6:32
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    @Gabe - thanks for your comment. I've taken the question as it stands to refer to long-term averge resource, rather than second-by-second resource, because AIUI that's what the original claim assumed. I'm happy to work through any of those points with you: please do post any of them as questions over on the Sustainability Stack; or, if you can find a notable claim about any of them, then please do post them as a question here. – EnergyNumbers Jul 28 '14 at 6:35

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