Wind Power: The Devil is in the Detail

 Take a look at this table from the USA Energy Information Administration (EIA). 

From a first glance it looks like the MW/Hr cost of on-shore wind is actually less than that for nuclear.

Meanwhile the price of off-shore wind is the same untenable basket case that it is over here.
This off-shore nightmare really needs no further discussion now. Maybe another day.

What about the on-shore figures?

The figures are full enough to give us a really good insight into the viability of wind turbine generators (WTG's) in the UK.

This table gives the levelised (or naked - no subsidy) costs and necessary charges.

It shows the obvious - that wind has no fuel costs.
It gives a viable price for each generation technology per MW/hr
It gives a price for the capital cost and running costs., including fuel where appropriate
Crucially it also gives the capacity factor needed for achieving this price MW/hr

This table is vitally important to understanding why almost all windpower in the UK is unviable without subsidy, and also why almost all on-shore as well as off-shore wind generation  in the UK is hugely more expensive than other generation technologies.

How come? It all comes down to the capacity factor (CF) used. Here it is a whopping 34%

We know from the table that almost all of the costs of running a turbine are fixed costs. This means that a WTG generating alot of electricity is going to have (as near as dammit) the same overall costs as a similar WTG generating much less.

Obviously the more productive turbine gets paid more. Remember - the running costs are fixed.

The amount of electricity generated over a year is directly related to the CF. Double the CF - double the amount of electricity generated. Half the CF then you halve the amount of electricity generated. Double the CF = double the income and vice sa versa.

We also know (from the table) the viable price for electricity MW/hr at the given capacity factor. (CF). After all, the whole point of this table is to provide price comparisons between generation technologies.

The table tells us that the system levelised cost for an on-shore wind turbine generator (WTG) per MW/hr to be viable  is $97 per MW/hr.

To achieve this price, according to the EIA, the WTG needs to operate with a CF of 34%

The costs are fixed. If the CF drops there is no fuel saving because there is no fuel. The potential loss of revenue has to be made up by increasing the cost per MW/hr.

If the WTG was to operate at 20% CF then the price needed to break-even rockets from $97 MW/hr to  $165 per MW/hr.

The rolling average UK CF is 27%. The English rolling CF is 25%. in the SouthWest this drops to 23%. East Stoke in Dorset, the CF would be about 20%. The Reading Turbine is around 15%. If I remember correctly, the highest individual on-shore English CF was in 2009 at Workington at 32%

Clearly without the double payment from the ROC subsidy there will be very few WTG's in the UK that are viable. Yet with the double payment even the utterly crap turbines can make a profit.

Nothing is going to get better about this.

There is no magic to increase the CF or wind speed. A turbine addicted to the ROC will always be addicted to the ROC

And you will pay for it.

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