Feeds

Carbon Trust: Rooftop windmills are eco own-goal

Perhaps we should stop subsidising them

5 things you didn’t know about cloud backup

Not only would rooftop turbines in built-up areas be an enormous money-pit (barring crippling electricity price rises), they would also be bad for the environment. More greenhouse gas would be emitted during their manufacture, shipping, installation and maintenance than would be saved at power stations. The Carbon Trust people considered the case of the SWIFT turbine, a representative model.

Assuming that the entire household population of UK urban areas has this machine installed ... in the majority of cases (over 80 per cent), yields are less than 500 kWh/year ... over 50 per cent of installations have a carbon payback of more than 20 years, which is beyond the expected life of the turbine ...

So an urban rooftop windmill normally produces well under 2 per cent of the energy requirements of an average UK household*, represents an enormous financial loss, and will normally increase the world's greenhouse gas emissions rather than reducing them. So you'd have to be mad to install one.

In fact, no you wouldn't - because the government will give you money or tax breaks for a roof turbine. Even though it's usually expensive and actually bad for the environment, thanks to the various kinds of eco-subsidies (particularly those built into the low- and zero-carbon buildings regs) it may make sound financial sense to buy a windmill.

Some government grants are not conditional on site wind speed and electricity generation potential. This carries the possible risk of grants being awarded to installations which save little carbon ...

Only certain sites amongst all places where small turbines could possibly be installed are actually suitable for installation ...

A range of policies is encouraging the growth of small-scale wind energy in the UK, including the Low Carbon Buildings Programme, Permitted Development Rights (PDRs) for domestic installations and the Code for Sustainable Homes.

It is recommended that ... In any future grant schemes, a criterion is used to measure likely carbon savings ...

You'd think that grant schemes with the phrases "low carbon" and "sustainable" in their titles would have such criteria, but this seems not to be the case.

This is all quite hard for the Trust to say - being eco-quangocrats, they are the kind of people who would love to believe in a Blighty powered largely - or even partly - by renewable microgen. But, through gritted teeth, they admit that "up to 1.5 TWh could be generated [annually] ... these figures are fairly low ... [if the cost of wind turbines halved, this] could change to 3.1 TWh ..."

"Fairly low"?

The UK used 2,700 terawatt-hours of energy in 2006, actually, so we're talking about a thousandth of our energy supplies at the very outside. A better description would be "insignificant" or "microscopic".

It would be nice to think that this finally puts a merciful stake through the heart of the seemingly unkillable home-windmill idea, but it probably won't. Even the Carbon Trust didn't much like reading their own numbers, and it will be surprising if anyone else bothers to heed them. For a lot of people, off-grid living and microgeneration are religious/moral standpoints, not sets of engineering techniques; they won't be swayed by mere numbers, even ones from fairly right-on types like the Trust.

The rest of us, though - unless we happen to live on a windy hilltop out in the boonies - might reasonably file the roof-turbine plans in the bin and think of something else. ®

*According to the UK Office of National Statistics.

Build a business case: developing custom apps

More from The Register

next story
Vulture 2 takes a battering in 100km/h test run
Still in one piece, but we're going to need MORE POWER
Boffins ID freakish spine-smothered prehistoric critter: The CLAW gave it away
Bizarre-looking creature actually related to velvet worms
TRIANGULAR orbits will help Rosetta to get up close with Comet 67P
Probe will be just 10km from Space Duck in October
CRR-CRRRK, beep, beep: Mars space truck backs out of slippery sand trap
Curiosity finds new drilling target after course correction
ANU boffins demo 'tractor beam' in water
The current state of the art, apparently
China to test recoverable moon orbiter
I'll have some rocks and a moon cheese pizza please, home delivery
What does a flashmob of 1,024 robots look like? Just like this
Sorry, Harvard, did you say kilobots or KILLER BOTS?
NASA's rock'n'roll shock: ROLLING STONE FOUND ON MARS
No sign of Ziggy Stardust and his band
Why your mum was WRONG about whiffy tattooed people
They're a future source of RENEWABLE ENERGY
prev story

Whitepapers

Endpoint data privacy in the cloud is easier than you think
Innovations in encryption and storage resolve issues of data privacy and key requirements for companies to look for in a solution.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Top 8 considerations to enable and simplify mobility
In this whitepaper learn how to successfully add mobile capabilities simply and cost effectively.
Solving today's distributed Big Data backup challenges
Enable IT efficiency and allow a firm to access and reuse corporate information for competitive advantage, ultimately changing business outcomes.
Reg Reader Research: SaaS based Email and Office Productivity Tools
Read this Reg reader report which provides advice and guidance for SMBs towards the use of SaaS based email and Office productivity tools.