Wind Power is the use of wind to provide the mechanical power through wind turbines to turn electric generators. Wind farms consist of many individual wind turbines, which are connected to the electric power transmission network. Wind turbine blades rotate when hit by the wind. And this doesn’t have to be a strong wind, either: the blades of most turbines will start turning at a wind speed of 3-5 meters per second, which is a gentle breeze.
Wind power contributed 18% of UK electricity generation in 2018, making up 52% of electricity generation from renewable sources. In the UK, it is a popular low-cost generation mode which is still dropping in price and delivers a rapidly growing percentage of the electricity of the United Kingdom.
Onshore wind farms have an impact on the landscape, as typically they need to be spread over more land than other power stations and need to be built in wild and rural areas, which can lead to “industrialization of the countryside” and habitat loss. Small onshore wind farms can feed some energy into the grid or provide electric power to isolated off-grid locations.
Offshore wind is steadier and stronger than on land and have less visual impact, but construction and maintenance costs are higher.
Historic Trends and Growth
Wind farms were initially made profitable by subsidies through Renewable Obligation Certificates. Early windfarms were part financed through the Renewables Obligation where British electricity suppliers were required by law to provide a proportion of their sales from renewable sources such as wind power or pay a penalty fee. The Energy Act 2008 introduced banded ROCs for different technologies from April 2009. Onshore wind receives 1 ROC per MW·h, however following the Renewables Obligation Banding Review in 2009 offshore wind then received 2 ROCs to reflect its higher costs of generation. The government announced on 18 June 2015 that it intended to close the Renewables Obligation to new onshore wind power projects on 1 April 2016 (bringing the deadline forward by one year). Support for offshore wind was moved into the government’s Contract for Difference support regime.
A 2004 study by the Royal Academy of Engineering using “simplification and approximation” found that wind power cost 5.4 pence per kW·h for onshore installations and 7.2 pence per kW·h for offshore, compared to 2.2p/kW·h for gas and 2.3p/kW·h for nuclear. By 2011 onshore wind costs at 8.3p/kW·h had fallen below new nuclear at 9.6p/kW·h, though it had been recognised that offshore wind costs at 16.9p/kW·h were significantly higher than early estimates mainly due to higher build and finance costs, according to a study by the engineering consultancy Mott MacDonald.
Onshore wind has a much bigger presence in the UK at the moment, just because the technology to support it has been around for much longer than offshore wind. Therefore onshore wind at the moment provides a much higher percentage of the total energy mix than offshore wind in the UK.
As technology has developed, the cost of electricity generation by wind has fallen significantly. In the 2019 CfD round, 6GW of wind was added to the grid at £47/MWh at 2019 prices; the first round that prices were lower than current generation costs. As of 2020 costs for offshore wind power stations is the lowest cost of any other UK electricity generation, less than 50% of the cost of Nuclear Power.
The above figure illustrates the rapid growth of wind generation since 2010. Until Jan 2018, the growth of offshore and onshore wind mirrored each other, however, after this point, the growth of offshore generation has increase and is set to take over the onshore generation.
The UK is significantly off track to meet the level of onshore wind needed to achieve the legally-binding 2050 net zero emissions target. New analysis from the industry body, RenewableUK, shows that without a change in policy, onshore wind capacity is expected to fall nearly 40% short of the target by 2030.
There is currently just over 13.5 gigawatts (GW) of onshore wind installed across the UK and the power it produces avoids over 14 million tonnes of greenhouse gas emissions every year. The Committee on Climate Change advised Government that onshore wind capacity needs to expand by at least 1GW a year to achieve our net zero emissions target, reaching 35GW by 2035. This would require approximately 29GW to be installed by 2030.
New analysis by RenewableUK’s Project Intelligence team shows that, on current trend, capacity will grow to only 17.8GW by 2030. Reaching this level depends on 4.5GW of new onshore wind farms being built without Government-backed contracts for new renewable power. Instead this new capacity would rely on Power Purchase Agreements with corporates or the merchant power price. Just under 1GW (740 megawatts) would be repowered, with older turbines replaced at the end of their life by new modern turbines.
In a lower growth scenario, onshore wind capacity would grow by only 1GW in the next decade to just 14.5GW by 2030 as the rate of new wind farm installations is outpaced by the retirement of older projects.
Only the high scenario in the analysis envisages significant growth in onshore wind with capacity growing to 24.4GW. Reaching this level would require supportive policies from Government, including allowing onshore wind to compete for new Contracts for Difference, setting planning guidance for repowering and enabling use of the most modern turbines.
Installation of new onshore wind turbines reached a peak of nearly 2.7GW in 2017, before falling by 80% in 2018 to the lowest level of new installations since 2011. The dramatic fall-off in new installations primarily due to policy changes implemented by Government after the 2015 election, including the closure of Contracts for Difference auctions to onshore wind.
|Low-Ambition Scenario “Business as Usual”||– No significant improvement in the existing regulatory framework.|
– Continued year-on-year decreases in input costs
– Stable operational costs
– Rate of new wind farm installations is less than retirement of older projects.
|Medium-Ambition Scenario||– Favourable regulatory reform (e.g. network charging and connections)|
– A robust carbon price.
– Sustained growth in public and private-sector demand for PPAs
– Incremental improvement in climate policy ambition
– No direct policy support for onshore renewables before 2030.
|High-Ambition Scenario||– Favourable regulatory reform (e.g. network charging and connections)|
– A robust carbon price.
– Sustained growth in public and private-sector demand for PPAs
– Incremental improvement in climate policy ambition
– Competition for new Contracts for Difference
– Setting planning guidance for repowering and enabling use of the most modern turbines.
|Net Zero Scenario||– Constant incremental increase to meet 2030 targets|
– No further assumptions made
Research suggests that in the future wind energy will be the most cost-effective source of electrical power. However, the effects of the growth of the wind turbine sector are being felt already, with UK wind power generating enough power for 2.4 million homes in 2011. It is estimated that by 2020 this figure will rise to 7.7 million homes.
Scientists are also working to build wind turbines which can continue to generate electricity even in extremely high winds (at present turbines must shut down in storms in order to avoid causing damage to the mechanism). Conversely, turbines which can function at very low wind speeds are currently in development, meaning that urban and suburban sites may become more suitable for the generation of wind energy.
The UK government’s Energy Technologies Institute (ETI) has proposed a novel, offshore vertical axis (dubbed Nova) wind turbine as part of a project to find ways of bringing down the cost of offshore wind power.
Financing & Landowner Considerations
A landowner with a suitably sized and located space for large scale wind turbine installations (5MW plus, around 2-20 turbines), may be able to rent land to specialist wind developers. These companies will usually pay for 100% of the project and will pay a sum based on the number of wind turbines and their total performance/energy output.
Usually your land will need to have the following attributes:
- An annual average wind speed of at least 6m/s
- Access for works vehicles (lorries, cranes, etc.)
- Not be too close to any dwellings
- A connection to the electricity grid
This kind of arrangement offers significant benefits; usually the landowner will have to cover no capital cost whatsoever, with the wind developer funding the project from the initial feasibility stage through to decommissioning. The financial benefits for the landowner are therefore risk-free and potentially very high, especially if the wind speeds are high.
What’s more, despite the large area needed for the installation of turbines (typically 25-40 acres per turbine), a very small percentage of the land is taken up by the turbine, leaving the remaining space free for normal farming activity. Livestock are also unaffected by the turbines.
Obviously such projects can have a large impact upon the surrounding area, so it is first necessary to obtain planning permission and engage in a public consultation. It is also necessary to bear in mind that you will often be tied into a contract for a long period of time, often 20 years, and you will have little control over the project (though by the same token you won’t have to maintain the system yourself).
On average, a wind farm planning application takes 2 years to be considered by a local authority, with an approval rate of 40%. Approximately half of all wind farm planning applications, over 4 GW worth of schemes, have objections from airports and traffic control on account of their impact on radar.
Financing a Wind Turbine:
The cost of wind turbines is greater than most other renewable sources. A similar pole mounted wind turbine could cost in the region of £20,000. Bigger systems like a 15kW turbine may well set you back £70,000.
Obviously, how much you spend is going to be determined by the return on investment and how much profit you earn from the SEG and cheaper electric bills. The good news is that the bigger the system the more likely you are to benefit and the payback period is shorter than you may think. Find out how much money your wind turbine is likely to make you here.
For most wind turbine installations, you are going to need two types of finance:
- First of all, you will need development at-risk capital which will be used to explore how suitable the site is and your planning application.
- Secondly you will need capital for the actual construction, buying the turbine and having it installed.
You will need to be clear on the return on investment that your new turbine is going to provide but there are number of sources where you can get finance apart from your own bank.
- NatWest have an agriculture division that can offer 100% finance with no deposit for farms that have the land available for a wind farm installation. Find out more about what they can offer here.
- Rural Finance Ltd also deal in agricultural finance and provide a specialist service to farmers and rural communities. Find out more here.
- The Carbon Trust is an international company that can help small business become more eco-friendly with the option of finance packages as well as advice and support on the best renewable solutions. Find out more about The Carbon Trust here.
- Eastern Counties Finance provides a wide range of support to farms and rural businesses including advice on farm energy finance. Find out more about them here.
- If you have land that would be suitable for a wind turbine or even a wind farm and you would like to lease that out rather than build yourself, then you can contact a company like Renewables First who will be able to judge if you are suitable.
The other option for many rural areas is to make larger constructions a community effort. An example is the Valley Wind Co-operative in Colne that is aiming to help produce cleaner and cheaper energy for the local residents.
As with other renewable technologies, wind turbines are eligible for the SEG and Feed in Tariff schemes which means that you can sell your excess electricity production to the grid. Whether you make any profit on your wind turbine energy production will depend on a wide range of factors, including:
- The size and potential output of your wind turbine.
- Its height – the general rule of thumb, up to certain limits, is that you should get a 1% increase in power generation for every meter.
- The quality of the turbine components, initial installation costs and ongoing maintenance needs.
- The wind speed that your site generally gets.
- Distance from obstructions that could affect the wind flow, such as houses, trees or hills.
- Height above sea level may also be another factor that you need to consider.
- Your own energy usage and how much excess you will be able to export to the grid.
Above all others, this is the key question to bear in mind when looking into wind turbines. The suitability of the site dictates the financial gain to be made from the wind turbine installation. A location suitable for the installation of wind turbines will have the following attributes:
- An average wind speed of at least 5m/s
- Free from turbulence caused by nearby obstacles such as hills, buildings and trees, which slow the wind down
- In the case of pole-mounted turbines, enough land on which to build foundations and attach guy ropes (if necessary)
- The site must not be in or near to a Conservation Area or anywhere in the grounds of a Listed Building
Urban and suburban sites are therefore highly unlikely to be suitable for the generation of energy with wind turbines, and are better suited to other renewable energy technologies, such as solar photovoltaic, solar thermal and ground source heat pumps.
Wind turbines are best suited to elevated and open sites in rural and coastal areas. It is for this reason that one finds many domestic and industrial wind turbine installations in Scotland, Ireland and Cornwall.
Assessing your local wind speed is the first step to take when making a decision on purchasing wind turbines. In the first instance, you can use the Energy Saving Trust’s (EST) wind speed prediction tool, which will give you a rough estimate of your area’s wind speeds: Wind Speed prediction tool
If the result of this preliminary test is that your area’s wind speed is greater than 5m/s, the next step would be to monitor the wind speeds that your property receives over a set period of time. At least 3 months’ monitoring is vital, although it is recommended that you monitor for 12 months in order to account for seasonal variations in wind speeds.
The best way to carry out this monitoring is to buy an anemometer (typically costing between £100-£750) and place it at the same height as that of the proposed turbine. The anemometer will measure average and maximum wind speeds, as well as levels of turbulence at your property, and log the data which can then be accessed by a computer interface. Some anemometers also measure wind direction, although this can be done with a separate weathervane.
Once you have monitored wind speeds for your area, it is also advisable to cross-reference the data with other information sources, such as the Met Office. Another useful resource is the DECC UK Wind speed Database.
If the results of the wind speed monitoring are encouraging, you can then arrange for an MCS-accredited engineer or technical surveyor to inspect your property and assess the feasibility of a wind turbine installation.