When the wind blows
PUBLISHED: 15:53 24 April 2009 | UPDATED: 15:59 20 February 2013
Seen as the future by many but often controversial, wind turbines are increasingly becoming part of the Kent landscape
Despite the current economic climate, which has seen a number of energy firms recently cutting back on their wind turbine programmes, the government remains committed to wind power. Through generous subsidies, it hopes that wind power will be the key to ensuring that the UK hits it target of deriving 15 per cent of its energy needs from renewables by 2020.
Kent already has one of the UK's largest operational offshore schemes. The Kentish Flats wind farm comprises of 30 turbines, each capable of three Megawatts (MW) of electricity. It is estimated that the farm, which is located six miles away from the coastline at Whitstable will displace around four million tonnes of CO2 over its 20-year lifespan.
There are now more offshore schemes intended for Kent, with two already given the green light from planners.
"The Thanet Wind Farm, which will be located seven miles out at sea from the Kent coast at North Foreland will be made up of 100 turbines. It will produce 300MW of electricity, enough to power 240,000 homes. This is significantly more than our other farm at the Kentish Flats," says Mandy Broughton of Vattenfall Wind Power, which is developing the farm.
On a grander scale and around 12 miles out to sea, the London Array project will cover 90sq miles between Margate and Clacton in Essex. The £1.5bn scheme, which is a joint venture between E.ON and DONG Energy, will have 341 turbines producing in total around 1,000MW of electricity or enough to meet the electricity needs of 750,000 homes. It is estimated that this project will represent nearly 10 per cent of the government's renewables target.
Mandy argues that in addition to the environmental benefits these schemes bring, there will also be other advantages for Kent.
"The total investment for completing our wind farm is around £780 million," she says. "A proportion of this will likely be spent locally with potential benefits for local suppliers and services.
"In the long term, a maintenance facility is needed during the 40-year operational life of the wind farm, which could require locally skilled workers. Tourism may also be boosted. Many visitors have been attracted to both onshore and offshore wind farm developments in the past."
Offshore Wind farms enjoy a relatively high level of public support. They are normally too far out to sea to be that visible from the shoreline and any environmental impact in the immediate area is relatively benign. By contrast, the public support enjoyed by onshore sites cannot be said to be the same.
"The problem with onshore wind turbines is that wind flow is slower, more variable and more turbulent and this dramatically reduces the power output compared to offshore" says Sean Furey, deputy director for CPRE Kent.
"The visual impact is also an issue. Most of Kent is probably unsuitable for wind turbines. The topography of the county is varied and quite sheltered. So, the most effective places for turbines would be on the ridges of the High Weald, the Greensand Ridge and the North Downs, which would alter the character of Kent radically."
Sean adds: "For many residents and visitors, they would see it as yet another degradation of Kent's special 'Garden of England' character, which could hurt the county's important tourism sector."
Evidence of public hostility to onshore farms was revealed during the recent inquiry over Ecotricity's proposed establishment of a small wind park for five 2MW turbines in East Langdon, near Dover. Dover District Council received hundreds of letters objecting to the planned farm and had to set up a relay system and marquee to accommodate the number of people attending a public consultation meeting earlier this year.
Ultimately, despite Ecotricity's claims that the 10MW wind park could generate up to 31 million units of electricity, enough to power 9,000 homes - almost 20 per cent of the homes in the area - the proposal was rejected.
Had this been an offshore site, then it's likely that public reaction would have been more accommodating. Instead, local concerns over potential noise, the visual impact and any possible effect on wildlife will always make the construction of onshore schemes more difficult.
Although much of the investment in renewables today is done by energy companies, there is nothing to stop anyone from getting involved in alternative energy production themselves. Micro-generation is a growing sector of the renewables market and when it comes to wind power, because the turbines are smaller and spread out over larger distances, it is seen by some campaigners against onshore farms as a better onshore option.
"We have had a very positive response to our efforts to increase sustainability, which include several wind turbines," says Peter Smith, chief executive of the Wildwood Wildlife Park in Herne Bay.
"The park has a number of turbines of various sizes which, combined with solar power, we use to generate all our electricity needs. Aside from helping the environment the great thing about generating our own power is that we are able to sell some of the energy we generate back to the National Grid, giving us a small income each year."
Anyone with enough space in their garden can install a small wind turbine. Typically a domestic system would be one to six kilowatts (KW), depending on the location and size of the home. Installation up to 1KW will cost around £1,500 whereas larger systems in the region of 2.5KW to 6KW would cost £11,000 - £19,000.
These costs are inclusive of the turbine, mast, inverters, battery storage (if required) and installation. Government funding is available at a maximum of £1,000 per KW of installed capacity, subject to an overall maximum of £2,500.
In general terms, you will need an annual mean wind speed of at least four metres per second (m/s) to be able to generate a reasonable amount of energy, and ideally in excess of 4.5 m/s.
This tends to only be achievable in rural areas and so most people in towns and cities are unlikely to get the most out of their turbines. It's also best to check with your local authority to see if your requirements necessitate planning permission.
The UK enjoys the best wind resources in Europe. So whereas countries on the Mediterranean might enjoy an advantage in solar energy, wind power is an area where the UK can capitalise. Turbines can blot a landscape and are not to everyone's taste. But then again, we might have to ask ourselves are they a price worth paying to stop something like climate change, which in the longer term would be more damaging to our landscape than any turbine could ever be?
Myths and facts
Myth 1: Tens of thousands of wind turbines will be cluttering the British countryside
To obtain 10 per cent of our electricity from the wind would require constructing around 12,000 MW of wind energy capacity. Depending on the size of the turbines, they would extend over 80,000 to 120,000 hectares (0.3 per cent to 0.5 per cent of the UK land area).
Myth 2: Building a wind farm takes more energy than it ever makes
The average wind farm in the UK will pay back the energy used in its manufacture within six to eight months. This compares favourably with coal or nuclear power stations, which take about six months.
Myth 3: Wind farms are inefficient. They are only operational 30 per cent of the time
Modern wind turbines produce electricity 70 to 85 per cent of the time, but they generate different outputs dependent on wind speed. Over the course of a year, they will generate about 30 per cent of the theoretical maximum output. This is known as its load factor. The load factor of conventional power stations is on average 50 per cent.
Myth 4: Wind power is expensive
Wind energy is one of the cheapest of the renewable energy technologies. The average cost of generating electricity is now around 3p to 4p per kilowatt hour, competitive with new coal (2.5p to 4.5p) and cheaper than new nuclear (4p to 7p). As gas prices increase and wind power costs fall - both of which are very likely - wind becomes even more competitive, so much so that some time after 2010 wind should challenge gas as the lowest cost power source. Furthermore, the wind is a free and widely available fuel source, therefore once the wind farm is in place, there are no fuel or waste related costs.
Myth 5: Wind farms kill birds
The RSPB stated in its 2004 information leaflet Wind farms and Birds, that "in the UK, we have not so far witnessed any major adverse effects on birds associated with wind farms". Wind farms are also always subject to an Environmental Impact Assessment.