The idea of taking energy from the wind and making it do useful work is an old one, used to great effect in draining mush of East Anglia, reating the most agriculturally productive area of Britain.

The technology has been brought up-to-date and now extremely elegant and efficient turbines can produce large quantities of energy through a wide range of windspeeds.

Case Study - Wind Power

Energy use at this pharmaceutical site in the rural south west of England is made up of electricity for site plant and office operational requirements, natural gas and fuel oil which are used building heating and steam generation process use. Based on 2007 data the site consumes 4,884,995kWh of electricity a year. There are also 122,000litres of fuel oil consumption which equates to 142,740kWh and an additional 116,095kWh of natural use. Half hourly data indicated a site base electricity load profile of ~520kW.

The identified scheme considers installation of 2 number 2 megawatt wind energy generator (WEG) turbines to generate electricity for site demand and export to the grid or other end users. It has been identified that annual site electricity demand is ~ 4.8GWh/year and that potential combined WEG output would be ~7.4GWh/year.

Taking this into account ALL on site demand can be met with notional WEG output with a further ~2.6GWh of electricity being available for export to the grid or potentially a private wire system to other industrial estate end users.

For the purposes of economic appraisal savings identified are calculated based on the combined value of displaced electricity (at 10p/kWh current price), Renewable Obligation Certificates (ROC’s) revenue at £34.30/MWh and the value of grid export electricity which has been estimated at a value of 5p/kWh which is thought to be representative of potential market acceptance.

Two implementation options are recommended for consideration, those being option 1 to enter into a long term design build and operate agreement with a wind energy contract entity whereby a pence per kilowatt hour (p/kWh) charge mechanism would apply and option 2 where the company would realise full capital investment for erection and operation of wind turbines at their site.

There is an identified cost benefit of £155K a year saving for option 1 and £563K per annum saving for option 2 with an estimated payback of 6.92 years against an estimated total capital investment of ~£3.9 million.

Indicative carbon dioxide savings from displaced grid supplied electricity by wind turbine generation output are 3,186.3 tonnes a year.