Blu-Wind Tower and Turbine Combination: 250Kw + 50M Tower

What is Wind Power?

The winds that blow across much of the world’s land masses can be harnessed by wind turbines to provide electricity. Wind turbines sited in suitable locations already provide a small, but growing percentage of European and USA electricity generation. In a variety of forms from traditional windmills to simple wind-driven water pumps, the power generated from this most natural form of sustainable energy has, over the ages, been used successfully all around the world.

Global investment into renewable energy surpassed $100 billion for the first time in history in 2009. And Wind power is leading this growth; in the four years from end-2004 to end-2008 wind power capacity has increased 250 percent to 121 GW.

Wind turbine technology combined with innovative new tower designs has also greatly improved over the last ten years, making wind turbines quieter and more efficient so that electricity generated from the wind can now compete with that from the more traditional coal and gas-fired and nuclear power stations.

Wind turbines are also beginning to be built at sea and in the future much of the world’s electricity requirements could come from both onshore and offshore wind farms. In addition, smaller scale turbine/tower configurations will start to provide a considerable share of local community, village and small town energy needs, particularly in the energy starved Developing world.

What is Green Electricity?

Have you ever stopped to think about where your electricity comes from? In Europe about two thirds of electricity requirements are generated by burning coal and gas in power stations. This releases millions of tones of carbon dioxide into our fragile environment, the main gas responsible for climate change, every year. The other third of electricity mainly comes from nuclear power, which has raised many cost, safety and environmental concerns.

‘Green or clean electricity’' means electricity produced from sources which do not impact negatively upon the environment. Of course, every type of electricity generation has some impact, but some sources are much greener than others. The cleanest energy sources are those which utilise the natural energy flows of the Earth such as sunlight, tides, geothermal heat and wind. These are usually known as renewable energy sources, because they are naturally replenished.

How does a wind turbine make electricity?
What influences the output of the wind turbine?
How much of the time do wind turbines produce electricity?
How safe is wind energy?
Local law and subsidies
What advantages do I get if I place the wind turbine?
Do I need permission for placing a wind turbine?
How much wind is needed to produce electricity?
How do I read the characteristics?
How much service cost is there?
If I supply the over production to the grid, will I get paid?
How much will the power company pay per kWh?
Can I use a wind turbine without a connection to the power grid (electricity network)?
What is the life expectancy of a wind turbine?
Who does the service and maintenance on my wind turbine?
Do I need a grid connection?
My farm/factory uses a lot of electricity. Can I use wind energy?
Does the wind turbine switch on and off automatically when the wind speed changes?
Does wind energy have an impact on the environment?
Do wind turbines influence birds?
Do wind turbines frighten livestock?
Are wind turbines noisy?


How does a wind turbine make electricity?

The simplest way to think about this is to imagine that a wind turbine works in exactly the opposite way to a fan. Instead of using electricity to make wind, like a fan, turbines use the wind to make electricity. Almost all wind turbines producing electricity consist of rotor blades which rotate around a horizontal hub. The hub is connected to a generator, which are located inside the nacelle. The nacelle is the large part at the top of the tower where all the electrical components are located. The wind turns the blades round, this spins the shaft, which connects to a generator and this is where the electricity is made. A generator is a machine that produces electrical energy from mechanical energy, as opposed to an electric motor which does the opposite!

What influences the output of the wind turbine?

  • The average wind speed. More wind means higher electricity production. It means both how fast it blows and how often it happens. More important is the average speed than the speed at any given moment.
  • The bigger the rotor diameter, the higher the output.
  • The tower height. Wind speeds increase at higher altitudes. So, the higher the tower, the more wind the turbine catches.
  • Turbine type; downwind or upwind. Most wind turbines face into the wind, these are called "upwind turbines" Turbines that face the other direction are called "down wind turbines". A downwind turbine produces less energy and wears out faster compared with an upwind turbine. The reason is that the airflow around the tower introduces turbulence.

Blu-Wind's partner turbines are upwind turbines.

Related entries: Two-bladed versus Three-bladed Wind turbines.

How much of the time do wind turbines produce electricity?

A modern wind turbine produces electricity 70-85% of the time, but it generates different outputs dependent on wind speed. Over the course of a year, it will generate about 30% of the theoretical maximum output. This is known as its load factor. The load factor of conventional power stations is on average 50%.

Example calculation for a BW250 Turbine and 30 meter tower:

One year has (24 * 365 hours) = 8760 hours. When full power (= 250kW) can be generated all the time, the theoretical yearly output will be 2.190.000 kWh. In practice this will be around 30% of this amount = 657.000 kWh.

How safe is wind energy?

Wind energy is one of the safest energy technologies. No member of the public has ever been injured by wind energy or wind turbines anywhere in the world, despite the fact that there are now over 100.000 operational wind turbines.

Local law and subsidies

Many countries and local authorities support and stimulate renewable energy. Please contact your Blu-Wind dealer to check what kind of subsidies or other support you can get from them when switching to wind energy.

What advantages do I get if I place the wind turbine?

Most important reason:
Wind turbines pay back for them selves in 3 to 7 years. After this period wind turbines generate electricity for many more years without significant costs. Contact your local Blu-Wind dealer to make a calculation for you.

On top of this there are various other advantages depending on the situation you are in:

  • A wind turbine may stabilize an instable grid.
  • You decrease your diesel need and cost.
  • You decrease the diesel generator noise.
  • You decrease your electricity cost.
  • You produce green energy for a better environment.
  • You educate your community by setting an example of a better environment

Do I need permission for placing a wind turbine?

Yes. Please contact your local Blu-Wind dealer for the details.

How much wind is needed to produce electricity?

The Blu-Wind tower -Turbine combination will start to produce at 4 m/s, however, with an average wind speed of 5 m/s it gets economically interesting to produce your own electricity with a wind turbine. Stronger wind produces more electricity. For example:

BW 250 Wind speed Annual production
5,0 301.928
6,0 471.323
6,5 559.720
7,0 647.532
7.5 734.572

How do I read the characteristics?

  • Nominal Power is measured in kilowatt (kW) or megaWatt (mW). Nominal power tells the maximum amount power that the turbine can produce.
  • Production is measured in kiloWatt hours (kWh) or megaWatt hours (mWh). Production tells you how much electrical energy will generate during a period of time. Often the time period is one year.

How much does turbine service/maintenance cost?

Wind turbines need maintenance. Service costs for Blu-Wind's partner turbines are low. The annual estimated service cost for a Blu-Wind tower and turbine is Euro 3,000 for 3 bladed turbine. The down-time for a Blu-Wind turbine during a maintenance job is limited to only a few hours.

If I supply the over production to the grid, will I get paid for?

This depends on your local regulations. In many countries you get paid for the kWh that you supply to the grid, please consult your local Blu-Wind dealer he is aware of all regulations and possible future changes.

How much will the power company pay per kWh?

This all depends on the country you live in. Many governments have rules and regulations regarding the prices per kWh. This should be checked on an individual basis, your local Blu-Wind dealer can help to make calculations.

Can I use a wind turbine without a connection to the power grid (electricity network)?

There are two types of wind turbines: grid-connected and non-grid-connected. The grid connected wind turbines are the larger ones that produce electricity. The non-grid-connected are usually the very small wind turbines that charge batteries only. Blu-Wind turbines can be grid connected, except for our Hybrid stand-alone Wind/Diesel system. See: What is a hybrid stand-alone wind/diesel system?

Related entries: What is a hybrid stand-alone wind/diesel system?

What is the life expectancy of a wind turbine?

Most medium to large wind turbines have a life expectancy of 20 years.

Who does the service and maintenance on my wind turbine?

When you purchase a Blu-Wind turbine from a certified Blu-Wind dealer, you can enter into a service contract with the Blu-Wind dealer or a local service company. The service contract ensures that your wind turbine gets the regular bi annual service it needs on time and you don’t have to worry about keeping track of the maintenance. For most wind turbine owners this is the preferred method.

Do I need a grid connection?

Blu-Wind and its partners manufacture grid connected and Hybrid Wind/Diesel wind turbines for off-grid purposes.

Grid connected: When connected to the grid (the local electricity network) and behind the meter, the electricity will be consumed directly by you at your house, farm or factory. Excess electricity produced will be fed into the grid. In this case a meter keeps track of your supplied kWh to the grid and your power company will pay you a certain amount of money per kWh (net-metering). This price is usually pre-determined and often regulated by the government. In times of insufficient wind, you will automatically draw electricity from the grid.

Stand-alone: In this case the wind turbine feeds electrical energy into a small isolated grid. Often powered by a diesel generator. Blu-Wind turbines and diesel generators use grid frequency to control energy production.

My farm / factory uses a lot of electricity. Can I use wind energy?

Yes! As a matter of fact, if there is space to install a wind turbine and there is sufficient wind, then any farm or factory can use a wind turbine. For example: A poultry farmer has a house and a large poultry shed and it consumes 120.000 kWh per year. There is sufficient wind available and the local regulations allow you to use a wind turbine. In this case a Blu-Wind tower with an 50 kW generator can easily produce 150.000 kWh per year. Enough for your own electricity needs. At times when there is not enough wind, you will automatically draw electricity from the power grid. In this case you only pay the power company for the electricity you take from them and the rest you get from your wind turbine. If you produce more electricity (150.000 to 120.000 kWh = 30.000 kWh) then you can sell the over production to the power company and they will pay you a certain amount per kWh delivered. Many factory or farm owners that use wind turbines use such a set up.

Does the wind turbine switch on and off automatically when the wind speed changes?

Yes, the system is fully automatic. It start automatically when the wind speed reaches at least 4 m/s, it follows the wind direction automatically and it slows down and stops automatically when the wind speeds reach or pass the maximum wind speed.

Does wind energy have an impact on the environment?

Yes, as wind energy is a clean energy it only has a positive impact! Wind energy decreases the use of fossil fuels, nuclear energy and other polluting energy sources. It also decreases CO2 emissions.

Do wind turbines influence birds?

Many people are concerned about the influence wind turbines have on the safety of birds. Extensive surveys show that very few birds are killed by wind turbines and that they have no influence on the bird migratory routes at all.

Do wind turbines frighten livestock?

Wind farming is popular with farmers, because their land can continue to be used for growing crops or grazing livestock. Sheep, cows and horses are not disturbed by wind turbines.

Are wind turbines noisy?

Wind turbines are not noisy. The evolution of wind farm technology over the past decade has rendered mechanical noise from turbines almost undetectable with the main sound being the aerodynamic swoosh of the blades passing the tower. There are strict guidelines on wind turbines and noise emissions to ensure the protection of residential amenity. It is possible to stand underneath a turbine and hold a conversation without having to raise your voice. As wind speed rises, the noise of the wind masks the noise made by wind turbines. For more information, read the facts about noise from wind turbines or why not visit a wind farm and experience it for yourself.