Tuesday, 23 March 2010

And still the power generation claims of the wind-power lobby get reported as fact

The Telegraph reports the breaking off a wind-turbine blade at a wind farm and ends the piece with this claim: 'The Whitelee windfarm... turbines can generate 322MW of electricity, enough to power 180,000 homes.'

Of course the key word there is 'can' because as well know windfarms rarely produce electricity at anything like capacity. Indeed The TimesM recently reported that:
'THE first detailed study of Britain’s onshore wind farms suggests some treasured landscapes may have been blighted for only small gains in green energy.

The analysis reveals that more than 20 wind farms produce less than a fifth of their potential maximum power output.

One site, at Blyth Harbour in Northumberland, is thought to be the worst in Britain, operating at just 7.9% of its maximum capacity. Another at Chelker reservoir in North Yorkshire operates at only 8.7% of capacity.

Both are relatively small and old, but larger and newer sites fared badly, too, according to analyses of data released by Ofgem, the energy regulator, for 2008.

Siddick wind farm in Cumbria, now operated by Eon, achieved only 15.8% of capacity, the figures suggest. The two turbines at High Volts 2, Co Durham, the largest and most powerful wind farm in Britain when it was commissioned in 2004, achieved 18.7%.

Turbine efficiency is calculated by comparing theoretical maximum output with what the farms actually generate. The best achieve about 50% efficiency and the norm is 25%-30%. '
I cannot find the generation figures for Whitelee but I doubt that it is more than 50% of the 322MW figure quoted in The Telegraph.

As an aside I have just looked at the always fascinating Neta site and see that for the last 24 hours this was the breakdown of power generation by type of power source:
Gas - 52.3%
Coal - 24.3%
Nuclear - 19.8%
Pumped Storage - 1.2%
Wind - 1.1%
Non pumped storage Hydro - 0.7%
Interconnect - 0.6%

That 1.1% is 12,206MWh; I wonder what the claimed capacity of UK Wind Farms is?

ChrisM reports in my comments that "Current capacity is 4122 MW with another 10,000 MW under construction". If this is true then wind farms were running at around 12.3% over the period I examined; impressive!


ChrisM said...

Current capacity is 4122 MW with another 10,000 MW under construction

Craig said...

I've lost count of the number of BBC reports on the industries that could lead us back into strong economic growth that choose renewable energy (especially wind turbine) companies as their prime example.

ChrisM said...

I can assure you it is true I got it from the RenewableUK website here
Sorry I should have included the link.
I have been watching the Neta/Electricity page off and on all winter, today was above average if anything, the very cold period in January was much worse due to a high pressure weather system. So when you need more power it does not tend to be there.
At the time there was a shortfall of gas supplies so they had to increase the coal fired power stations to keep up the supply.
Irony is alive and well.

Richard said...

Excellent post. I have linked to it from mine. Hope that's OK.

Weekend Yachtsman said...

I don't understand how 12,206 can be 12.3% of 4122.

Am I confusing MW with MWh?

Can someone explain this.

And Craig - indeed. They don't seem to understand that "jobs" in things that don't add value are actually a cost, not a benefit. Very annoying.

Not a sheep said...

WY: I believe it is a MW / MWh comparison, my figures are for a 24 hour period.