Wind Energy - price per watt

Those of you who've looked for facts about wind energy prices on the internet will probably agree with me that there's too much opinion and not enough data on-line.

I'm no expert, so I've taken the published price of some wind farms and other power stations, along with their rated outputs. I've used the assumption that the wind turbines develop their rated power for a third of the time (capacity factor .33) which is in line with a recent REF survey of the best-sited UK wind farms.

I have calculated the price per watt (delivered) of generating capacity by dividing the price by the output. Here are the figures, per watt.

STATION	Type	Price	Rated Power	Capacity Factor	Available Power	Source of info	Price per watt
------	------	------	------	------	------	------	------
Hadyard Hill	Wind	£85M	100MW	.33	33MW	BWEA	£2.57
Solway Firth (proposed)	Wind	£375M	180MW	.33	60MW	BBC	£5.41
Scroby Sands	Wind	£75M	60MW	.33	20MW	BBC	£3.75
Whitstable	Wind	£2700M	1000MW	.33	333MW	Business Week	£8.11

For comparison:

Olkiluoto 3, Finland	Nuclear	£2000M	1600MW	.75	1200MW	BBC	£1.67
Sanmen etc China	Nuclear	$5300M	4000MW	.75	3000MW	Bloomberg	£0.80
Severn Power	Gas	£350M	800MW	.75	600MW	BBC	£0.58
Kingsnorth (proposed)	Coal	£1000M	1600MW	.75	1200MW	E.On	£0.83
Killingholme (proposed)	Coal / CO2 storage	£1000M	800MW	.75	600MW	BBC	£1.67

Remember when making comparisons that the coal and gas price per watt doesn't include the price of the fuel itself. I've used a load factor of .75 for nuclear, coal and gas, so an 800 MW unit is treated as delivering 600MW of electrical energy. For the Westinghouse Sanmen/Yangjiang contract with China (Dec 06) I've used an exchange rate of $1.00 = 50p.

To return to wind turbines - recent figures on wind farm performance from Germany are somewhat unsettling:

A report from German energy company E.On quotes an estimate that, although by 2020 Germany plans to have 48 gigawatts of "installed wind capacity", this will equate to only two gigawatts of stable fossil fuel capacity.

This would be equivalent to a capacity factor or 2/48, or.0416. The effect on the electricity price per watt installed would be as follows:

STATION	Type	Price	Rated Power	Available Power	Price per watt
Hadyard Hill	Wind	£85M	100MW	4.16MW	£20.43
Solway Firth (proposed)	Wind	£375M	180MW	7.49MW	£43.39
Scroby Sands	Wind	£75M	60MW	2.50MW	£30.00
Whitstable	Wind	£2700M	1000MW	41.6MW	£64.90
--------------	------	------	------	------	------
Olkiluoto 3, Finland	Nuclear	£2000M	1600MW	1200MW	£1.67
Sanmen etc China	Nuclear	$5300M	4000MW	3000MW	£0.80
Severn Power	Gas	£350M	800MW	600MW	£0.58

I welcome comments on these figures. I'm not pro or anti; I just want to know what's going on. Billions of pounds of taxpayers' money are being put into wind farms. If the figures above are anywhere near the truth, the money is being wasted.

On top of this, most of the wind energy generated at night cannot be used by the Grid. People are asleep, factories are closed, and wind energy cannot be stored.

My own turbine, as I write this, is stationary, as it was yesterday, and my batteries are flat; I'm back on the mains. We have a second, larger turbine which will be installed for testing soon. To satisfy my curiosity I calculated the price per watt of my "600W" wind turbine on a breezy day:

STATION	Type	Price	Rated Power	Available Power	Price per watt
Suttonelms 1, Leicestershire	Wind	£1500	600W	30W	£50.00
Suttonelms 2 Leicestershire	Wind	(larger)	being installed

Nigel Deacon / habitat21 website

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