Search the internet for the keywords 'wind power', 'manufacturing', 'process' and 'industry' and see what you find. After a little delving in relation to business, the sector you might come across most is farming and 'wind farms', but not much about wind power for manufacturers and process plant operators.

A pity, for it seems these enterprises would benefit by offsetting their energy bills with 'green' electricity generated from one or more wind turbines on their premises. This is no longer far-fetched: in recent decades wind power generation has become a highly developed industry.

But there is hot debate about wind farms. Like the wind, informed arguments on the value of the power generated blow this way and that. True, in certain conditions, some large-scale turbines consume electricity in order to operate, and there are questions about the frequency and strength of the wind during the year in the British Isles, and will the contribution from wind make a real difference in the long run? The fact remains that the world is faced with an energy crisis, made more critical now with global warming. In UK industry, other factors are driving the search for efficiency and economy: energy consumption shows no sign of lessening, electricity prices continue to rise, and fossil fuel may be in short supply within two decades. Worldwide agreements like Kyoto and economic concerns have prompted the UK government to tell the country's energy industry that by the year 2010, 10% of supply must come from renewable sources. Despite arguments, off- and onshore wind farms are proliferating, as is research into other forms of renewable energy generation. Europe is well advanced in the design, development and manufacture of large and small wind turbines. And there is proof that wind power is viable for industry. Take Ford's Dagenham estate in Essex, claimed to be London's first large-scale wind park. Located on two sites, two 85m-high turbine towers, each supporting 80-tonne generator units and blades measuring the same as a Boeing 737 aeroplane's wingspan, are supplying electricity into the company's new high-tech Dagenham Diesel Centre (DDC), which opened in November last year. With a combined capacity of 3.6MW, the two wind turbines are expected to generate over 6.7million kWh of 'clean' electricity per annum. It is claimed this will meet all electricity requirements for the DDC, which produces a high performance 2.7-litre V6 engine. In comparative terms, the energy would be enough to supply over 2,000 homes, nearly 7million units per annum. The wind turbines will also generate annual emissions savings of carbon dioxide (5,762 tonnes), sulphur dioxide (67 tonnes) and nitrogen oxide (20 tonnes). In other words, if coal, oil or gas-fired power stations had generated the electricity needed, these emissions would have been produced. In comparison to so-called 'brown' energy, wind power produces no such environmentally harmful by-products. There are interesting features about the Ford case. First, the automotive manufacturer doesn't own or operate the turbines, it didn't install and doesn't maintain the system. It simply buys the electricity generated from a pioneering wind power developer and licensed electricity supplier called Ecotricity, the company responsible for the whole outsourced project. It installed the German-made Enercon wind turbines, manages the power supply to Ford and provides all related support. If the wind drops, the plant draws on power from conventional sources, controlled through a switching and metering system. In practice, the force and frequency of wind at Dagenham, not the windiest place in Britain, has been assessed as adequate to make the scheme work effectively. And the real point is, Ford has decided that, all things considered, the project is economically viable. Figures are not published, but Gary Freedman, Ecotricity's partnership manager, says: "The big factor is actually not so much the financial outlay as financial risk and that's the big thing in energy: what everyone wants to avoid is risk." He explains that in the case of supplying renewable energy, most customers want to get on with their core business, and not be distracted by buying, installing and maintaining a power generating plant. Risk arises because it's hard to predict changes in regulations, technology and market forces likely to occur over the next 30 years, the life of a large wind turbine. Other issues also represent risk, such as making planning applications. This may involve studies, reports and appeals costing six-figure sums for largescale and environmentally sensitive sites. Applications may fail. Freedman says this is why companies like Ford outsource projects of this kind and his firm deals with the cost and risk of the planning process: "We take on the risk and that's the biggest thing, as much as the capital outlay." At the other extreme, the risk is less severe and simpler. Based in Nottingham, Iskra is a DTI SMART award winner and manufactures an advanced, 5kW wind turbine addressing a market that includes small commercial and industrial premises. Typically mounted on a single post tower and supported by guy ropes, this is a stark contrast to the sleek machines at Dagenham. The turbine incorporates a high electrical efficiency, three-phase alternator using rare earth permanent magnets. The machine has a 20-year life and is designed to be cost effective, robust yet simple, and require little maintenance. Whether a wind turbine is large, like those at Dagenham, or the other extreme cited here, a key priority when considering wind power is to first consult the local planning office. Environmental and aesthetic issues are paramount. According to yes2wind, a pro-wind support group, a legal requirement for plans exceeding 5MW output means the developer has to engage a consultant to define issues in the form of an environmental impact assessment (EIA). Local considerations Local planning departments, briefed by central government to encourage renewable energy initiatives, might not object to an installation. However, away from the metropolitan areas, it is the parish councils that may block progress. A number of points need to be considered including noise, annoying 'flicker' or shadows caused by the rotating turbine blades, and such factors as the effects on wild bird life, should your site be located near wetlands, for example. In this country, because each location is different, it is vital to find out from the planners, or use a consultant, to establish all the local factors before spending a lot more time and money on the project. According to Iskra, noise output from its 5kW device is low, thanks to careful rotor design and no necessity for a gearbox. With regard to the proximity of domestic housing and the possibility of annoyance, the company says: "It is generally accepted that if the wind turbine noise is less than 10dB(A) below background noise levels, this will not cause a nuisance to neighbours." As a general rule, it advises the nearest residents to the wind turbine should be more than 100m away. Depending on the processes used in the plant, the background noise at industrial sites may vary, but the value above indicates what would be acceptable. Regarding operating conditions, Iskra offers the following advice: the turbine should be sited as far away as possible from buildings or trees, which may deflect the wind and create unwelcome turbulence. As a guide, the turbine itself should be positioned about twice the height of any obstructions in front of it in relation to the direction of the prevailing wind. Taller masts are available - 15, 20 and 25m versions - to address issues of obstruction. In general, the company says, the higher the tower, the higher the average wind speed that will be encountered. The distance on the ground between the turbine mast and any obstruction should be 20 times the height of each obstruction. The space around the turbine mast needs to accommodate guy wire supports and allow for lowering the mast to access the turbine. If need be, the whole assembly can be moved at any time, although the new site would require concrete foundations to be installed. The turbine's three-bladed 5m diameter rotor is mounted on a standard 12m mast, which means it is sufficiently high to prevent it being a hazard to people and property in the vicinity. Connected by a cable and remote from the turbine, ancillary control gear is mounted on a panel just over 1m2 in size that carries a pair of inverters, a rectifier box, meters and wiring. It may be mounted alongside the factory's main consumer unit, or outside. John Balson, Iskra's director of engineering design, outlines the economic and practical considerations. He says that by installing a wind turbine and becoming an electricity generator, savings may be achieved. The power generated is used instead of buying electricity from a supplier. In addition, a reward may be claimed for becoming a producer of renewable energy. A Renewable Obligation Certificate (ROC) is submitted to Ofgem, the energy regulator. In return, a payment is received. Balson says: "It's very much having your cake and eating it. If you generate the power you can claim for having generated it, even if you immediately use it on site. You get to keep the energy and you get paid just for having generated it and using it yourself." The bottom line The cost of buying the turbine, mast and full two-day installation plus testing and approval from his company amounts to between £15,000 and £16,000 in total. This will yield a saving of around £1,200 per annum, with £800 of that due to not buying in electricity and the other £400 in the form of a cheque from Ofgem. Surplus energy could also be sold back to the grid, but Balson says this is not always easy and most small-scale generators would want to use all the electricity themselves. The return on investment may seem low, but electricity prices show no sign of going down. A larger, higher output turbine would yield more. He points out there is another benefit, less tangible but equally important: that of visibly making a contribution to a greener environment. For some companies that is vital, especially if their customers apply a policy of environmental concern and want their suppliers to demonstrate the same commitment. Between these two extremes lies another approach: organisations on industrial estates or business parks may share a communal wind turbine installation, creating a small-scale wind farm. This is already happening and lends itself to many options, either through the estate developer or management company, or by several companies taking the initiative themselves. Gary Freedman says Ecotricity is pursuing the potential of this market. In particular, his company's merchant wind power scheme offers an attractive way to deal with a serious barrier to the uptake of wind power generation: the planning application. "It's a very lengthy, difficult and drawnout process and it often leads to appeals; it's a really big stumbling block, it's also very expensive. In other countries around Europe it's a lot smoother." Size matters For a large enterprise considering wind power, using the services of a company such as Freedman's would save much time. A smaller business might be unable to afford the luxury and have to go through a number of steps: either engaging consultants or undertaking the planning application itself; checking its energy requirements and where savings would best help; investigating and shortlisting suppliers; finding out about wind conditions and the appropriateness of the particular site; investigating grants or setting up the administration of ROC or sales of surplus energy. Help with some of these tasks may be obtained from a turbine manufacturer or a service company picked to supply and install the equipment. Iskra's John Balson says instead of spending £3,000-£4,000 doing expensive wind monitoring and data logging on the site, the former Energy Technology Support Unit (ETSU) - now part of Future Energy Solutions - offers a less costly solution. It provides data about wind conditions throughout the UK, down to a square kilometre. In conclusion, besides the potential pitfalls posed by the planning process, the key issue is payback: at Dagenham, Ford has gone ahead on a scheme worth £3m, for which it only pays for energy supply and no commitment to equipment. But slowly, around the country, smaller-scale installations are beginning to appear next to factory plant. This visible gesture marks a business out as being environmentally responsible, a PR benefit in itself. A factor that may accelerate take-up - and wake up local planners and parish councils - is the talk of pressure on primary energy production and distribution, mostly during the winter. Media reports this year drew attention to the possibility of so-called outages or 'brown-outs'. Investing in a means to counter this risk might prove timely and wise. And guess when the wind blows strongest?