Frequently Asked Questions

The blades of the turbines are usually made of either reinforced polyester, fiberglass or wood-epoxy. The towers are usually made of either concrete or steel, tubular in shape and mostly painted light grey. Light grey is often used due to the inconspicuousity under most lighting conditions. Finishings are usually matte, to decrease the amount of reflected light.

On average, the size of onshore wind turbines are around 2.5 - 3 MegaWatts (MW). Offshore wind turbines currently reach just over 6 MW, with a rotor diameter of approximately 120 meters.

Wind Turbines generally start operating around wind speeds of 4-5 meters per second. Maximum power of a Wind Turbine is reach at 15 meters/second. Wind Turbines cannot function and will shut down during periods of very high wind speeds, such as for example during gale winds, which are around 25 meters/second.

Modern Wind Turbines can produce around 70-85% of the time, but output is dependent upon the wind speed.

A few factors need to be considered when designing a wind farm. One main factor to consider is that the area that is desired for the wind farm should be as wide and open as possible in the prevailing wind direction, with as minimum of obstacles as possible. The turbines must also be easily accessible for maintenance and repair. Noise levels can be calculated as well so that they fall within the levels of sound that are required by national legislation.

The type of wind turbine selected is all dependent upon certain conditions such as the landscape where the wind turbine is to be located, the wind conditions, the noise levels, the national/local rules on the heights of the wind turbines, how easily can it be transported to the site location, the possibility of earthquakes occuring at the farm location, etc.

Construction of a wind farm can take about 2 months for a 10 MW wind farm and around 6 months for a 50 MW wind farm.

The actual costs in building a wind farm vary. However, the major cost is for the wind turbine itself. This is typically a capital cost and usually is paid for upfront and may account for roughly 75% of the costs.

Wind pass over the blades, creating a lift, which causes the rotor to turn. Once the blades start to turn, it turns a low-speed shaft within the nacelle. The gears within the nacelle connect the low speed shaft of the rotor with a high speed shaft that in turn moves the generator. As the shafts continuing spinning, it drives the generator to produce electrical energy. Electricity within the generator is then transported to a transformer which converts the electrical energy into the right voltage required for the electrical grid.

Electrical output of a wind turbine depends on the wind speed and the size of the turbine. Wind Turbines manufactured today have an output range anywhere between 250 watts and 7 MW.

Solar Energy is the process of using the Sun's energy in order to generate electricity or heat, using a system of mirrors or panels.

Photovoltaic Cells (Solar Cells) convert sunlight directly into electricity. Photovoltaic cells are generally made up of silicon, and are usually arranged on rectangular panels (as shown in the picture above).

When the sunlight hits an Photovoltaic cell, the energy knocks the electrons free of their atoms, which allows flow through the material. Resulting Direct Current (DC) electricity is then sent to an inverter for conversion into Alternating Current (AC).

Solar Concentration systems generally use mirrors that are arranged in a series of long, parabolic troughs, a circle surrounding a "power tower" or a large round dish. This is done to focus the sun's reflected rays on heat-collection. Concentrated sunlight heats water or heat-transferring liquids to generate steam, which then is used to power turbines to generate electricity, as shown in the below diagram.

Solar Energy can be used any where the sun shines. The use of solar energy can allow for the reduction of electric bills. Many businesses/farms have been seen to install enough solar panels that would allow of a reduction of costly summer rates or even pay their entire electric bill.

The cost of Solar Energy comes down to the performance of the system. Certain factors determine the performance of a system, such as the inverters, panels, size of wiring, connection of the wiring, mounting/racking, conditions of the surrounding environment, etc all affect the value of the system. The total cost of a solar panel system depends upon the panels themselves and the rest is determined by electrical wiring components, inverter, racking/mounting hardware, and labor to install the panels.

The power that a solar panel produces in comparison to the power it can achieve are two different things. A simple method to calculate this amount is to determine the number of "peak sun hours" your particular location receives. Any reputable vendor should have this information. Peak Sun Hour is defined as one hour of 1,000 watts per sqaure meter sunlight. You can multiply the watt rating of a solar panel by the number of peak sun hours in your location in order to get a rough estimate of how much power a solar panel can produce. Please make note that the sun hours vary on the season, and are the lowest during the winter season.

1) Solar Power does not produce any polluting emissions, including those emissions that cause global warming

2) Solar Power reduces electric bills for both commercial and residential consumers.

3) Sunlight is infinitely renewable so long as the sun exists

4) Solar Panels are silent (since they do not have moving parts), rarely need maintenance, and are relatively easy to operate

5) When the demand for electricity is high, utilities can use the panels to generate extra energy rather

Solar Energy can be used to power a building, heat a house, power a filter in a swimming pool, heat water tanks and much more. The possibilities are virtually endless!

The actual costs in building a wind farm vary. However, the major cost is for the wind turbine itself. This is typically a capital cost and usually is paid for upfront and may account for roughly 75% of the costs.

Biomass is biological material that is used as a renewable energy resources from plant or plant-derived materials. Biomass can be used directly or can be convered into energy products such as biofuel.

Biomass power plants burn biomass fuel in boilers to heat water and turn steam turbines, which in turn produces electricity. Biomass fuel is anything from landfill trash to wood.

Wood Fuel

Crops

Rubbish

Landfill Gas

Alcohol Fuels

Biomass can be used to generate electricity, liquid fuels or heat.

The most simple way is through Direct Combustion. Using the boilers can produce steam to use for the production of electricity directly or within an industrial process.

Another method to generate electricity from biomass is through the process of Gasification. Instead of simply burning fuel, this process converts it first into combustible gases. This is then burned to create electricity, power industrial applications, fuel vehicles, or be converted into synthetic fuels.

Bioethanol is a type of alcohol that is made by fermenting the sugar components of biomass. Ethanol, in its pure form, can be used to fuel cars. However, it is usually used as a gasoline additive to improve vehicle emission.

This is the process in which energy is built up under the Earth's surface and then rises to the surface in the form of heat. When this heat naturally creates steam or hot water, it is harnessed and used for turning a steam turbine to generate electricity.

Geothermal Energy can be used to heat spas, pools, homes, greenhouses and aquaculture ponds. However, Geothermal energy is one of least explored sources of renewable energy.

Usually, geothermal systems cost a little more to install than a conventional fossil fuel system with air conditioning. However, it has a lower operational cost and no fuel deliveries. Geothermal systems also do not cause any atmospheric emissions such as carbon dioxide, carbon monoxide, and hydrocarbons.

Geothermal systems cost less to operate than electric, propane gas, kerosene, oil, electric heat pumps, or natural gas.

Volcanic Systems, which are usually small but are well developed for electricity generation

Sedimentary Geothermal, which are naturally occuring limestone or sandstone rocks that have water.

Hot Rocks allow for the creation of Engineered Geothermal Systems in which developers artifically create a reservoir for water to flow thorugh hot granite rocks.

Geothermal heat is generated from the slow decay of radioactive elements within the Earth.

This is a system in which the hot rocks, that contain the geothermal energy, do not have a permeable reservoir. In the EGS, the reservoir needs to be created, which can be done in either two ways:

1) Hydraulic Fracture Stimulation which is used to open up natural fractures or zones of weakness in rocks. This can be done by injection of water under high pressure into the rock

2) Injection of Acid into the rock, which can help to dissolve the minerals. This can enhance the permeability of the rock along the existing fracture zones.

This is the use of the mechanical energy of flowing water by moving it through piping called penstock, which then turns a generator which produces power.

High efficiency

High level of reliability

Low operating and maintenance costs

Can easily adjust to meet load changes

The cost of Hydroelectric power depends on the size of the power plant. However, the larger the hydroelectric power plant, the cheaper the cost per kilowatt to produce the electricity.

When the cost of hydroelectric power is compared to the other means of producing electricity, it only costs about 1/3 of the cost for fossil-fuel production and less than 1/4 the cost of gas turbine electrical production.

Producing electricity from waves or tides is optional. Water from high and low tides can be used to spin turbines that can produce electricity.