Energy answer is blowin
September 1st 2005 Ian Clay attended the launch of a revolutionary new wind turbine intended for domestic and commercial use. But asks the question ‘Is the technology a futile gesture or a genuine solution?’
By 2010 the Government is committed to the task of having 10% of the UK’s energy demand to be met through renewable sources be they solar power, wave power or wind energy.
This initiative is of course part of the wider campaign to reduce the levels of CO2 emitted by the UK per year (currently 560 million tonnes) and popular philosophy would have us believe therefore slow down global warming.
We are all familiar with the dramatic pictures of offshore wind farms and those atop hillsides but Windsave Limited has pushed the concept with the introduction of the Plug ‘n’ Save wind turbine suited for domestic and commercial use. The product is in the very simplest terms a wind turbine that sits on the roof of your house or building and generates supplementary 240V electricity which feeds directly back into your own ring main.
The Windsave rooftop model is expected to produce around 1kW of electricity (units can be combined for commercial properties generating up to 6kW). In order to ‘spread the word’ British Gas has signed an exclusive agreement with Windsave to make the roof top turbines available to all UK households.
Dr Diane Montgomery, head of environment strategy at British Gas said "Having a roof top turbine means householders can save money and help do their bit for the environment - initial estimates show one unit could cut annual domestic electricity bills by up to one third and reduce CO2 emissions by a half a tonne per annum."
The micro wind generators are plugged directly into the mains through a standard 3 pin plug and can operate in wind speeds as low as three miles per hour. A cable leads directly from the turbine into a control box where electronics smooth out the ‘rough’ electricity created by the wind power and convert it to match the mains frequency so it can be fed into the household mains through a 13A plug.
In order to address health and safety concerns about allowing these units to be installed by the general public British Gas plans to use its network of engineers to install the turbines which, similar in size to a satellite dish, can be bolted on to a wall or gable end. The company’s engineers will also be on hand to maintain the systems through an annual maintenance contract.
The technical requirements of the generator were developed by AEG Electric Motors. Based upon the company’s 90mm frame motor and included in its design features is a specially developed braking system that prevents over speed in high winds. It also has special rotor laminations and windings to maximise efficiency, along with rare earth magnets to achieve the rated power output. Windsave chose AEG as one of the requirements for the system was that it would have to be ‘maintenance free’. By their very nature the wind turbines are in difficult to access locations and the present system offers a 10 year working life.
The cost
But what will such a system cost? The initial thought is that the installed cost for the Windsave system will be £1000 which if you take energy savings themselves into account could mean quite a lengthy payback. However, there are certain grants and financial incentives available which will make the payback far quicker. Although exact figures are not available a significant grant (perhaps as much as 50% of the initial cost) will be made available to those looking to install the system. As well as off setting the initial spend Renewable Obligation Certificates (R.O.C’s) are also worth investigating. If a commercial site (or domestic user) can submit its electricity meter readings to the DTI then it should be eligible for an R.O.C worth around £60 per year. Obviously if you have more than one turbine then the savings will be multiplied.
Other questions surrounding planning permission and noise pollution have also been answered. The belief is that planning permission for a turbine presents no problem as long as the unit is within 2m of a boundary wall and not more than 2m above the top of a house/premises.
Encouragingly all units that have been put through for planning permission have thus far proved to be acceptable. In terms of noise the blades of the turbine have been electronically balanced (much as the wheels of a car are balanced) and therefore the noise level is 47dBA. This level is perceptible of course but should not be obtrusive.
The Windsave unit is not the answer to the looming energy crisis that the UK will have to face in the next decade. IP&E believes the answer to that particular political question is nuclear power (see TMC Smith article May 2005 supplement).
However, perhaps that is expecting too much of the system and not really what its purpose is.
If a well informed energy or facilities manager can tap into the funding available for the system and work through the paperwork surrounding the R.O.C’s then, along with the savings in their electricity bills they could actually save a tidy sum of money. A good example of when, as the old adage goes "if you look after the penny’s then the pounds will look after themselves." | 
