Dorset Renewable Energy Strategy Seeks Endorsement

The Dorset Renewable Strategy Update received a mauling when it was first released for Public scrutiny. Particularly it was lambasted for its doctrinaire enthusiasm for covering Dorset with anything up to 360 huge and ineffective wind turbines. (the so-called "realistic" scenario was for 180)

The DEG (now renamed the Dorset Energy Partnership) have supposedly reworked this document. But really little has changed. Even the errors are still there. (more on that later). This reworked version has been released only to selected groups for "endorsement". I have yet to find any publicity for it anywhere for the general public.

So what about the errors?

I will limit myself to the section that is supposedly explaining Capacity Factors, otherwise this post would go on for ever. Below are the correct figures for UK Capacity Factors, taken from the RESTAT Site Here (Renewable Energy Statistics - Dept Energy and Climate Change - see bottom of linked page titled Load Factors there are a set of excel spreadsheets)

The Dorset Renewable Energy Strategy (DRES) is Here See Section 1.5 page 6

 First we have the 30% Capacity Factor Myth
 "wind power technology has a capacity factor of 0.3, or 30%"

 This is WRONG. At best, making such a statement shows a lack of basic research. At worst it is a deliberate attempt at misinformation.

Notice that from the DECC figures, the average CF for the whole of the UK has NEVER even reached 30% let alone become a typical average. For England it is worse. The 10 year rolling CF is less than 25%. The South West (i.e. including Dorset) it is even lower (23.5%) and has dipped to 17.7% in 2010. This document is supposedly about Dorset - right?.

This is not a matter of just  a "couple of per cent".

A 30% CF generator, over a year, will produce 150% of the energy of a 20% CF generator. So essentially this incorrect DRES statement inflates the energy generation we would expect from a Dorset wind turbine by around to 50%. (from high to low the SW CF is inflated by between 17% and 69%)

Some UK turbines DO make it to 30% - but only about 7% of the English fleet manage it. Even then, none are in the South West.

93% of the English turbine fleet have a CF below 30%.  Actually over 70% fail to even hit 25% nationally.  (See earlier post and prof. Jefferson report link Here).

The South West comes third from bottom of a very dismal English CF league.

 The table 1.5.1 in the DRES then uses the UK national CF average of 27%. At least that is an improvement on the mis-truth directly above it in section 1.5, but this is the UK average NOT the English average,  let alone the (worse) South West figure.

Again the figure is WRONG and grossly inflated - especially when related to Dorset.

As an aside, this table also states the off-shore CF as 35%. This is WRONG. In 2008 (the windiest year in the last 12) offshore NEARLY made it to 35% (34.9%). That is as high as it has ever got. Mostly  it has been around the late 20%'s to early 30%'s. Solar PV CF is given as 10% when it is more like 6 -8% in the UK. Then there is biomass and sewage gas. Laudible as these thermal plants are, they are still thermal plant. Even a  new CCGT plant would have difficulty getting a CF over 80% so, with no references,  the quoted 90% CF looks like a bit of extra and unnecessary guilding.

 2. Then we have "Full Power" myth:
 "a wind turbine will typically be generating electricity for 80% of the time, but will only be generating at full power for a smaller % of time, say 10- 15%."
 These are the power output curves for a Nordex turbine (P graph) and a GE (formerally Enron) 1.5MW turbine.

 A turbine only produces full power when the wind reaches about 12 m/s -  Beaufort Scale Force 6-7. A Force 8 is a full Gale.

 This is a graph of typical UK wind speed distribution over time from Here

Can anyone tell me when and how we manage to  get 10-15% at full power out of this? (i.e. 0.12 at 12m/s?)

Now the Bit that is almost (but not quite) a Myth

"producing power for 80% of the time"

There is a grain of truth in this - although it is a very small grain and that grain relates mostly to windy areas. It is almost certainly inflated and untrue for less windy areas - like Dorset.

But the real problem with this statement is that it obfuscates the simple and wholly damning fact that wind turbines operate at considerably below their CF for MOST of the time. This is because they only produce significant amounts of power during periods of high wind. MOST of the time they are producing very little (if any) power. This is accentuated in low wind areas - like Dorset.

This section in the DRES on Capacity Factors is  totally dissociated from the true figures you would expect in Dorset. The section grossly inflates the capabilities of Wind turbines that would operate in this area and so promotes potentially incorrect assumptions on the viability and practicality of building turbines in Dorset.

Essentially these figures in the DRES obscure the true worth (or lack of it) of potential Dorset Wind farms.

The DEP analysis of the data appears to extend solely to what they are told by their peers in RenewablesUK.

Any formal Strategy, especially a strategy that could promote a massive level of industrialisation of a rural area MUST be based on accurate figures and MUST remain impartial.  Unfortunately this document fails on both counts.

Yet it is supposedly good enough for "endorsement".

It will be interesting to see whether our councillors allow themselves to get railroaded by this travesty.

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