Buying a small
A step by step guide to site selection,
planning and funding.
Table of Contents
Introduction ............................................ 2
A Small Wind Turbine System .............. 2
Assessing Your Project......................... 4
Energy Generation Estimation................... 4
Planning Constraints ................................. 5
Locating the Turbine.................................. 6
Selecting the Tower................................... 6
Electrical Connection................................. 7
Funding ..................................................... 7
Domestic ....................................................... 7
Community Schemes .................................... 8
Planning Permission Application ......... 9
Funding Application ............................ 10
Delivery ................................................... 10
Installation ............................................ 10
Selling Your Surplus Power................ 11
Surplus Power Sales ............................... 11
Renewable Obligation Certificates........... 11
Issue 1 September 2006
This is a step by step guide to all the issues that need to be addressed when planning
and getting a small wind turbine from Dulas.
As far as possible, Dulas will help and guide you through the process to make it as
simple as possible for you.
Before spending any money there are some important questions that need to be
answered and the first section of this guide will help you to do that.
1. How much energy will it generate?
2. Is the proposed site suitable?
3. Is planning permission likely to be granted?
4. How will the turbine be funded?
5. How much will it cost?
To help you with some of these steps Dulas have provided this guide.
Once you have determined that your proposed site is suitable for a small wind turbine then you can go ahead
with the remaining steps:
1. Getting an all inclusive quotation from Dulas.
2. Obtaining planning permission.
3. Getting any funding.
4. Placing your order.
5. Selling your surplus power and claiming ROCs.
Before progressing into looking at your site and situation in detail it may be helpful to read some of the guides
that are available from other organisations that will give you some background information on small wind
systems. The most useful and relevant of these are from:
• The British Wind Energy Association: http://www.bwea.com/small/
• The Energy Savings Trust: http://www.est.org.uk/uploads/documents/aboutest/wind_energy.pdf
There is also a Frequently Asked Questions (FAQ) section on the Iskra web site which contains further
information, and is frequently updated: http://www.iskrawind.com/faqs/faqs.htm
A Small Wind Turbine System
There are many parts that make up a small wind turbine system.
1. Turbine. This converts the
energy from the wind into
electricity. It does this using
highly efficient aerodynamic
blades, which are in essence like
aeroplane wings or propeller
blades. The blades drive the
generator round which in turn,
generates electricity. In the case
of the Iskra this is three phase
AC power at around 400V, which enables relatively long wires to be used between the turbine and the
electrical connection, with minimal loss of energy.
The Iskra AT5-1 has many innovative design features which make it one of the best small wind
turbines on the market, and you may view a more detailed technical specification at:
2. Tower. The turbine needs to be mounted onto a tower so that is safe from humans, and also the
higher off the ground the turbine is, the more energy it will generate. This is because nearer the
ground the wind is slowed down by friction with the earth, as well as buildings or trees getting in the
way. Dulas offer two types of tower;
• Guyed Tower. This has 4 wire guy wires that go from half way up the tower to the ground,
and these enable the tower itself to be a lot smaller, lighter and therefore slightly cheaper, as
well as needing smaller foundations.
• Free-standing Tower. This is a single ‘monopole’ which is larger and stronger, and therefore
does not need guy wires, and takes up a lot less space on the ground. It is however slightly
more expensive and needs larger concrete foundations.
3. Inverter. The AC power from the generator is not only the wrong voltage to be connected to the
national grid, but also, as the wind speed changes so does the rotational speed of the turbine, and
therefore the frequency of the power generated. The power from the generator therefore needs to be
converted to DC and then fed into an inverter, to ensure that it is always at 240VAC and 50hz, as
required by the UK’s grid system.
4. Cable Trench. Generally a cable trench will need to be dug between where your wind turbine will be
installed, and your electrical connection point. Sometimes this might be done using a ‘mole’ which can
tunnel a cable duct under a road, or other hard surface.
5. Meters. In order to charge your electricity supplier for any energy that you export to the grid, you need
to have a new bi-directional electricity meter installed which will work both when you buy (import) and
sell (export) electricity. To claim your sale of Renewable Obligation Certificates (ROCs) you will also
need a ROC meter, which keeps track of all the energy your turbine generates, irrespective of it being
used by you, or exported to the grid.
Shown below is a simplified block diagram of how all the system components are connected.
400V AC Inverter
Your Property Meter
Dulas shortly hopes to offer an off-grid package which when combined with a battery pack, and optionally
solar PV panels and/or a diesel generator will enable the generation of “mains” power where there is no grid
Assessing Your Project
Energy Generation Estimation
Wind speed varies with time, from nothing on calm days to occasional violent gusts. If
the wind speed at a site is recorded over a year, it will be seen to vary about an
average wind speed value. This is the annual mean wind speed (AMWS) and is an
indication of how much wind energy is available. In the UK, AMWS could be as low
as 4 m/s (9.0 mph) for an inland site to around 8 m/s (13 mph) or higher on the most
exposed sites. The majority of sites in the UK suitable for a small wind turbine
however are between 5 and 6 m/s.
You can get a reasonable estimate of ‘windiness’ of the site from its postcode. By
entering your postcode into the Iskra web site you can get an estimate of the AMWS and expected energy
output for your site. http://www.iskrawind.com/windchecker.htm
Of course, this is only an approximate method. The actual wind speed at your site may also be influenced by
the local topography and any nearby obstructions such as trees, buildings etc. However, it will provide you
with a useful indication of the likely energy capture from the wind turbine.
Once you have your estimated wind speed you can see the expected annual energy that your turbine will
produce, and of course, the revenue that you can expect from your turbine.
You may find that if your AMWS is significantly less than 5 m/s that your annual energy generation may be
lower that you would wish for, and might make it difficult to cost justify the purchase of any small wind turbine.
Please bear in mind however that the AMWS provided from your post code is only an estimate, and a good
site, e.g. at the top of a slope, may have a substantially higher wind speed than indicated.
The following graph gives an approximate indication of the energy that the Iskra AT5-1 turbine can generate
per day and per annum.
Note: 1MWh = 1,000kWh or 1,000 units. A typical UK house would use about 4MWh per annum, while a
community centre, school, farm or commercial premises could use more than 20MWh.
A site with an AMWS of 5m/s should generate 8.7MWh per annum, which equates to an annual saving, or
income, of approximately £1,000 per annum. A site with an AMWS of 6m/s should generate 13.1MWh per
annum, which equates to an annual saving or income of approximately £1,500 per annum. All the equipment
has a design life of 20 years, and of course nobody knows what will happen to future electricity prices.
The database of wind speeds used by Dulas was developed by the DTI and is called the NOABL database. It
does however have some limitations, and the average wind speed and energy estimates produced from it, are
subject to a number of potential inaccuracies:
1. It is based upon a 1km square grid, and depending upon the topology of the area in which the site is
located, there can be significant differences between areas within the 1km grid.
2. Sites on the top of hills, especially with South West facing slopes, could be expected to have a
significantly higher AMWS than other sites.
3. There has been very little research into how built up areas affect the AMWS, but it is reasonable to
assume that the AMWS in urban areas would be significantly lower than the NOABL database would
4. The NOABL database does not take account of the impact of “sea breezes”, and therefore may
significantly under estimate the AMWS in coastal regions.
5. The AMWS, whist an important indicator of energy capture, is not the only determining factor. Other
parameters such as the density of the air, which increases the energy capture and is normally higher
on the coast, or the amount of turbulence, which reduces it and is much higher around buildings and
other obstructions, will have a significant effect.
Dulas will discuss these factors with you on the site survey and always try and indicate how they may affect
your expected annual energy generation from your wind turbine.
Planners are generally very supportive and pro-active towards small wind generation projects, and are obliged
under Government rules to consider them in a positive light. Often just calling your local planning authority to
explain you are looking at such a project can be worthwhile to get some initial feedback. We have excellent
and very successful supporting documents to help with your planning application.
There are however a number of specific planning related issues that may prevent you from installing a turbine
on your site and it would be wise to ensure that you are not going to fall foul
of any of these before proceeding.
1. Military installations. A small wind turbine will not be allowed in
close proximity to a military airfield or radar installation.
2. Proximity to neighbours. A small wind turbine should be located at
least 50m from the nearest neighbour, and ideally 75m to 100m
depending upon the ground cover and tress etc.
3. Designated areas. Whilst there is not an absolute ban on small wind
turbines in National Parks or Areas of Outstanding Natural Beauty,
you may find it more difficult to satisfy the local planning officer.
4. Civil Airport. If you live close to a civil airport, e.g. Gatwick or Heathrow, you should contact the
airport authority in advance of applying for planning permission, to see if they have any objection.
There is no precise rule about what “close” means, but anything less than 20 miles away would be
advisable to check with them first. They probably won’t object if you are more than a “few” miles away,
but they may take a long time to respond, so best to make the enquiry early in the process.
5. Neighbours. You should also make sure that your direct neighbours are not going to object to your
application, as not only will that make it more difficult for you to get planning, but no matter how
worthwhile getting a wind turbine may be, it’s probably not worth falling out with your next door
6. Noise. This is often one of the most emotive issues for objections to large and small wind turbines,
and unfortunately there is a lot of miss-information out in the public domain. Dulas will provide you
with detailed information on the expected noise levels and provide evidence to support your planning
application, including dispelling some of the myths around about wind turbines and noise.
It is essential in England and Wales to get planning permission to install a small wind turbine, but Dulas will
help you with this process and provide you with all the supporting information you need.
Locating the Turbine
Ideally, the turbine should be sited as far away as possible from buildings or trees, which may block the wind
and cause turbulence. See the figure below illustrating where a wind turbine should ideally be located.
Other considerations include:
1. It must also be at least 50m, (ideally more), from the nearest neighbour’s property to avoid noise or
flicker being an issue.
2. Access to the site will be needed for a lorry or crane in order to deliver and install the turbine pole.
3. The turbine should be located away from busy public areas, e.g. school play areas or busy car parks.
The Iskra AT5-1 turbine is not suitable for mounting onto a domestic roof, as it would impose too much stress
onto the building and Dulas do not currently offer a version of the AT5-1 turbine for mounting onto a
Another consideration is that the longer the distance from the turbine to the property, the longer and more
expensive the cable will be to connect the turbine to the electrical grid. Typically a distance of 100m – 150m is
reasonably economic, but distances of more than 300m, while possible, will become very expensive.
Selecting the Tower
The towers are available in a range of heights from 9m – 15m. The choice of tower type and height is
dependant upon a number of factors including:
• In some areas the planners may impose a restriction on
taller towers, and they may mandate a 9m tower. This is
quite likely in National Parks and Areas of Outstanding
• A guyed tower may not be considered suitable for
locations which could be subject to vandalism, e.g.
• A taller tower may be recommended where there are
buildings, or other obstructions, near the turbine
• The free standing tower uses considerably less ground
space than the guyed tower, and may be more appropriate
for a semi-urban setting, e.g. an industrial estate.
Following a site survey, Dulas will advise on the choice of tower
type and the pros and cons of each option.
All towers need to have lightning protection installed and this is
provided by Dulas fully inclusive in the price of the selected tower.
In order to use the electricity generated by the turbine, it needs to be connected to the mains electrical supply
via an electrical panel which is supplied by Dulas.
This panel performs a number of
1. It contains a rectifier which
converts the three phase
“wild” AC from the turbine
into DC suitable for use by
2. It holds the inverter(s)
which convert from DC to
grid synchronised AC.
3. It has safety fuses and
isolator switches, for the
input from the turbine, and
output to the grid.
4. It holds various meters for
measuring the energy
generated by the system
and the voltage and
current coming from the
The electrical connection may be either to a single or three phase supply, depending upon the type of
electricity supply to your property.
You may also need to get permission from your local electricity supplier to make the grid connection, but
Dulas will contact them on your behalf and make the required arrangements.
The types and amounts of funding available for purchasing and installing a wind turbine depend on the
purchaser and the area. Renewable energy installations can receive funding from several sources.
In England, Wales and Northern Ireland until recently there was funding
available from the Clear Skies Programme (www.clear-skies.org). This grant
scheme has now been replaced by the Low Carbon Buildings Programme
(LCBP) http://www.lowcarbonbuildings.org.uk managed by the Energy Saving
Trust http://www.est.org.uk The level of grants is broadly the same but with
some additional criteria:
1. £1,000 per kW installed up to a maximum of £5,000 or 30% of total installed cost.
2. The grant must be spent within 6 months of being awarded.
3. The property must meet a minimum level of energy efficiency e.g. 270mm loft insulation, cavity wall
insulation, basic central heating controls (timer & thermostat) and low energy light bulbs as
The new scheme is open for applications by submission of a paper copy downloaded from the Energy Saving
Trust website. There is no carry over of unsuccessful applications from Clear Skies.
The application process is relatively simple and quick and Dulas will provide you with all the information you
need to complete the application form.
For grants to be awarded, all installations must be carried out by a registered
installer under the DTI's Clear Skies programme.
The Low Carbon Buildings Programme offers grants to Community Schemes, and there are many other
organisations that may provide additional funding support for specific community projects some of which are
listed here. Please contact Dulas for advice on the type and sources of funding that your project may be
eligible for and assistance with completing applications for funding.
You may however like to contact directly some of the following organisations below who look favourably on
community applications for small wind turbines.
Projects for community groups and not for profit organisations which have a
positive impact on the community.
The Trust is designed to assist the creation of new renewable energy
sources in the UK, encourage research and development of renewable
electricity sources and promote education in the community on new
renewable energy generation.
Funding will be provided to non profit or charitable organisations and or
organisations involved in education and or work at community level to cover
the costs associated with the installation of small-scale renewable
technology and a proportion of the funding requested may be used for
educational purposes (Up to 20%). Funding may also be requested for
feasibility studies into the installation of small-scale renewable technology.
There will be a maximum grant value of £30,000 (Thirty Thousand Pounds)
for installations. Contact: Nigel.French@EDFEnergy.com
The total cost of a small wind turbine installation from Dulas is made up of a number of items, some of which
vary from site to site and the type of tower you choose. It is not therefore possible to provide an accurate
estimate of the cost until a full site survey has been completed, the following however is a guideline.
1. Iskra AT5-1 Turbine: £7,500
2. Tower: £2,000 - £3,000 depending upon type and height.
3. Electrical connection: £3,000 - £4,000 depending upon type of grid connection.
4. Foundations and installation: £3,000 - £7,000 depending upon type of tower, site conditions and
who undertakes the work.
Total: £15,500 - £21,500
V.A.T. is charged for domestic customers and charities at the reduced rate of 5%, and the standard rate of
17.5% for others.
Of course any grant you may be entitled to may reduce this substantially, e.g. the £5,000 from the Low
Carbon Buildings Program for a domestic customer.
Dulas will always install the tower and turbine as this maintains the guarantees and ensures your eligibility for
a grant. You may however arrange your own trenching for the cable and excavations for the foundations, in
line with Dulas’s specifications which we will issue to you. This may save you some money off the above
Dulas will not provide you with a quotation until all the areas of uncertainty have been identified and resolved
and we are confident that we can meet every aspect of the requirement. We will however be able to provide
you at an early stage with a budgetary estimate so you can make an early assessment of the level of funding
that will be required.
Dulas follows a very clear and simple process in order to be able to give you an all-inclusive and accurate full
turn-key quotation for your small wind turbine installation.
1. Initial Evaluation. Based upon the information you provide Dulas will assess the suitability of your
site and proposed project for a small wind turbine. If there are any areas of concern we will discuss
these with you and ensure they can be addressed before proceeding to the next stage.
2. Site Survey. A full site survey will be undertaken by a member of the Dulas engineering team to both
ensure that the site is suitable and to obtain all the information that
will be required to generate a complete quotation and subsequent
planning and funding applications.
3. Analysis. We will analyse all the information gathered from the
site survey and fully cost any special items that have been
identified during the process. We will then produce a complete
quotation for a turn-key installation including the turbine, pole,
electronics and installation.
Planning Permission Application
Having decided to go ahead with a small wind turbine the next step is to obtain planning permission for the
The planning regime for small wind turbines has been made a lot easier in the past year, and with growing
acceptance of the need for renewable energy, planning offices and local residents are becoming less resistant
to potential installations. None the less obtaining planning permission can be a lengthy and complex process
and the easiest way to get it done is to let Dulas do all the work for you.
The key issues that any planning application will need to address are:
1. The benefits of a small wind turbine to the environment and
greenhouse gas emissions.
2. The safety on the installation.
3. Potential noise intrusion from the turbine.
4. Visual impact.
Should you wish to undertake the planning application yourself then Dulas can provide you with example text
from previous applications and guidance notes on how to go about the process.
The Government has published guidelines for planning officers to follow when assessing an application for a
wind turbine and it is essential that all the areas of this guidance are covered in any planning applications.
These guidelines can be downloaded from: http://www.communities.gov.uk/index.asp?id=1143908. Planning
applications can now be filed electronically and the Government has set up a central web site giving general
guidance and making this process a bit easier: http://www.planningportal.gov.uk/.
The application process for the LCBP grant is relatively straightforward and Dulas will provide you with all the
information you need to complete the application form. The form, and associated guidance notes, may be
downloaded from the LCBP web site at: http://www.lowcarbonbuildings.org.uk/how/.
In typical Government fashion however the form must be completed by hand and therefore, as much as we
would love to pre-fill it for you, we’re afraid you must complete the form yourself and
send it off.
For community funding applications Dulas will help you to complete the application
forms and where appropriate attend meetings with the potential funding organisation
to help you present your case.
Dulas will also assist with any other funding application you wish to make to the
many organisations providing support to community schemes.
Once you have obtained planning permission, and whatever funding you are entitled to, you are ready to
place your order for your wind turbine installation.
Dulas will confirm your quotation, including any amendments that may have
become necessary following the planning process, and provide you with re-
validated written full quotation and estimated installation date for your turbine.
If you are happy with the quotation and wish to proceed then all you need to do is
sign the order confirmation and send it back to Dulas along with your deposit.
Dulas will endeavour to keep you fully informed of any changes in the expected
delivery date and will work closely with you to ensure that all aspects of the installation proceed as smoothly
Dulas holds stock of all the items required for an Iskra turbine installation at its warehouse facilities and Dulas
will arrange for all the required items to be delivered to the site as close to 9AM as possible on the first day of
Dulas makes a standard charge for this, and this charge is inclusive of Dulas’s delivery costs from its
suppliers. This charge is a mandatory charge and Dulas does not allow the self collection of towers or
This delivery charge is also inclusive of the delivery of the foundation kit to the site in a separate delivery to
the tower and turbine.
The installation comprises of multiple different aspects and it is possible that these will be undertaken by
different engineers, possibly on different days. Dulas will however always seek to minimise the disruption at
your site and will discuss and agree with you the dates and method of each aspect of the installation.
The key steps in the process are:
1. Site Preparation. This includes laying the concrete foundations for the pole and possibly digging a
trench for the electrical connection to be made. You may undertake any, or all, of this part of the
project yourself in order to save money, and Dulas will provide full detailed instructions and drawings
to enable you to do this, or arrange it yourself. The following tasks are part of this phase of the project:
a. Purchase of the cable from the turbine to the electrical panel
b. Digging of trench to hold the cable
c. Laying of cable in trench
d. Backfill of trench
e. Purchase of concrete for the foundations
f. Digging of foundation hole to required length, width and depth
g. Setting of foundation hardware.
h. Laying concrete
2. Electrical. Dulas will supply and install all the electrical components that enable the wind turbine to be
connected to the grid and for you to claim your ROCs. It is also possible that the local electricity
company will need to change your meter for a bi-directional one.
3. Tower. The tower will be delivered by truck, usually with a crane attached, and in a matter of hours it
can be mounted onto the foundations and erected.
4. Turbine. Normally at the same time as the pole is installed the turbine will also be delivered and
mounted onto the pole.
5. Commissioning. Once all the elements are in place the turbine will be commissioned and will start to
generate power and saving you money.
Selling Your Surplus Power
Any energy that your turbine produces will first be used within your own property and this will have the effect
of reducing your electricity bill by the full amount of the energy saved.
Any surplus power, e.g. on windy days, or when you are not using much power yourself, can be sold back to
your electricity provider.
Surplus Power Sales
The rate at which your provider will pay for your surplus power varies considerably, and it may be beneficial
for you to shop around and maybe change your supplier.
Listed below are power companies that may purchase the energy you generate from your wind turbine for a
better rate than your current supplier.
CompanyName WebSite Contact Email Phone
EDF Energy www.edfenergy.com Mark Thompson email@example.com 07875 110451
Green Energy www.greenenergy.uk.com Claire Adam firstname.lastname@example.org 01920 486156
NIE www.nie.co.uk Jenny Boyd email@example.com 028 9068 5089
Ecotricity www.ecotricity.co.uk Gary Freedman firstname.lastname@example.org 01453 769333
e-on www.eon-uk.com John Slater email@example.com 02476 425295
Good Energy www.goodenergy.co.uk firstname.lastname@example.org 0845 456 1640
Tradelink Solutions www.tradelinksolutions.com Penelope Christophorou email@example.com 01923 285583
Npower www.npower.com Louisa Gilchrist firstname.lastname@example.org 01905 340646
Renewable Obligation Certificates
In addition however, you may also get credited with Renewable Obligation Certificates (ROCs), which are in
effect a bonus for generating renewable energy. You will get one ROC for each MWh (1,000kWhs) you
generate. For a typical site in the UK, this should be in the region of £300 - £400 per year, and is paid for all
the energy you generate, no matter if it used by you or exported to the national grid.
We hope you have found this information guide useful, but if you require any further
assistance please contact Dulas and we will be pleased to help.
Email: email@example.com Web: http://www.dulas.org.uk
Phone: 01654 705005 Fax: 01654 703000