There is windy talk taking place in that big building by College Green. No, not the Cathedral, I mean the Council House. Under discussion: a proposal to build two wind turbines at Avonmouth for the purpose of generating electricity.

This is a fantastically bad idea. Supremely Bad. Short of building a BRT route along a cycle path I can't think of a worse idea (note: That's me off the fence then. More to follow on my research into BRT economics). Let's suspend disbelief for a moment and try to follow the chain of reasoning that leads to a local council building turbines:

  1. The council needs electricity
  2. Wind Turbines generate electricity
  3. The council should build some Wind Turbines

This can't be the reason behind this decision, since Wind Turbines are a very inefficient and unpredictable way of generating electricity. Over at the Burning Our Money blog, Wat Tyler discussed the Danish example. Although the official statistics for the Danes are that they get 16% of their national power from Wind, it would be more accurate to say that they offload their wind power onto their neighbours, and import a more predictable supply from foreign fossil or nuclear sources.

Good Intentions

A quick skim through the council's websites provides the intentions behind this idea:

  • prevent the release of many thousands of tonnes of CO2 per year.
  • control an element of its own power supply stream. That is, the council can sell the power the turbines generate to their own buildings at a lower price than if bought in the open market.
  • lower energy costs for our city's local public services.
  • generate its own ‘green’ electricity, as at present demand for renewable electricity far outstrips supply.
  • reduce its carbon footprint and help meet government targets.
  • be provided with ‘green’ energy for the life of the turbines (i.e. 20 to 25 years).
  • actively promote a sustainable energy future for Bristol and its communities.

Of these seven intentions, six are politically driven, and will be paid for by our Council Tax regardless of their underlying economic viability. "Lower Energy Costs" is at least mentioned, but is not exactly getting top billing. And it's an unlikely outcome given the implicit unreliability of Wind Power. There's not a lot else to be said about the carbon footprint arguments - either you believe the sky is falling or you don't. The goal that really puzzles me is "to control an element of its own power supply stream"Are the council worried that the National Grid will declare war and cut off strategic supplies? Or perhaps they fear an Anschluss if w're overreliant on Scottish Power. I can't see the point in seeking energy Isolationism.

After all, why stop at Energy? Consider that Bristol as a city in inextricably dependent on others for our food and water. Damn the Merchant Venturers - let's plough up the Downs and plant carrots; let's turn Cabot Circus into a water tank. With a planned & sustainable diet of fresh vegetables and a handful of mud, Bristolians could relax safe in the knowledge that they were living the traditional lifestyle of their ancestors, free for the vagaries of international financiers, globalised food markets and fickle foreign producers (i.e. Somerset). Until Winter of course, when we all die of thirst, starvation and malnutrition. Or choke on a piece of Queen Anne's lace.

Clearly we're not going down the self-sufficiency route for food and water, for very good reasons. Therefore it is reasonable to be sceptical about similar arguments about the need for independence in power, particularly if the generation system is intrinsically unreliable (i.e. Wind) and under the management of public sector managers. Local government officers are career bureaucrats - which is no insult; bureaucracy has its place. But their historic performance in market oriented endeavours where there is exposure to risk is not good. Examples? Take your pick, but locally the school building programme - particularly Redland Green School - is a good starting point.

Following the Money

Other than allowing the city to purchase the third millenium's answer to the Papal Indulgence (The Carbon Credit) and giving the Energy Management Unit a new toy to play with - which I suppose would distract them from signing any more declarations on our behalf - would this policy make much of a difference to the council's 'leccy bill, and therefore to Council Tax?

There's no Budget Book from the Council for 2008/09 yet, so for a quick back of a fag packet (only smoked outdoors) calculation we can use some figures from the odious Carbon Reduction Strategy 2007. In that year, the city spent just over £7,000,000 on "building energy". Let's keep the numbers simple and say the Council spends the same ever year and pays 0.10 pence per kWh on the wholesale market, which gives a total energy usage of 70,000 MWh every year, or an average of 190MWh every day.

The proposal is for two turbines rated at up to 3MW. "Up To" is the key bit of the sentence, as wind turbines average out at around 25% of their top capacity, since the wind doesn't always blow. So a more reasonable figure for the wind farm is 1.5 MW of generating capacity, with an output of 36MWh ever day, or about 19% of the Council's energy needs which - using our original assumption - would cost £1.3 million to buy.

The going rate for capital purchase of a Wind Turbines is somewhere around £1,000,000 per MW, so the full price would be around £6,000,000. So early in the fifth year of operation, the turbines break even and the next twenty years are just gravy.

But all the averaging hides the problem that even if the wind does blow, it doesn't necessarily blow at exactly the same time you need power. The purveyors of wind power would rather you didn't know this: you can't run a power grid using wind unless you've got a much larger traditional source of generating capacity to smooth out the supply. And we haven't discussed maintenance, spares and other running costs.

The Personal and the National

There's no way in hell that wind can deliver anything close to the predictable 350 TeraWatt Hours of electricty the United Kingdom needs every year.

Now I don't care about the spurious economics of Carbon Footprints, but I'm always keen to lower my electricity bill. UK households have an average annual domestic consumption of around 5 MWh of power (Bristol's figure is somewhere around 4,200-4,600 kWh annually), but if you want to find out your figure you could sit in front of the meter with a paper and pencil and do some sums. Or, like me, you could buy an Owl Wireless Electricity Meter:

Owl

Stick the sensor around your incoming power cable, and you can find out in excruciating detail exactly how much you're spending on electricity.

Alternatives to Alternative Energy?

"Alternative" tends to be used as a negating modifier: "Alternative Medicine" doesn't make you healthier, "Alternative Investment" doesn't make you richer, and of course "Alternative Energy" doesn't generally increase available power.

But there is some cause for interest in the sector: have a look at Bristol's own Marine Current Turbines, who are building a 1.2 MW tidal power generation system off the coast of Northern Ireland, and have plans for a Canadian installation generating nearly 4MW of power. Another local research team in the tidal power sector trade as Tidal Generation Limited.

It's still early days. Another decade of work is needed before this technology is genuinely commercially viable (for example the MCT Northern Irish project required a significant government grant). But tidal power generation is worth watching.

The Party Political Bit

David Cameron, leader of the Conservative Party, is famously an advocate of Wind Power. This is not his fault - he is, after all, a product of the British education system and is thus woefully unprepared for dealing with any matter of public policy involving science or engineering.

Say what you like about the French - and I do - but at least they've got the sense to put the Engineers in charge rather than the Classicists .