Following on from my previous post on the applications of solar power for the home, the next part of this renewable energy series looks into the effects and uses of wind, whether this be for electric radiators, hot water, or another use. With the main usage, of course, being electricity. As we have been using this power for centuries (sails etc...), it seems only fitting that wind power has become a prevalent force in the small-scale renewable energies market. In this post I will attempt to cover the basics of the technology, its applications, and to what extent it is cut out for the task of small scale energy production.
Wind power is the conversion of wind into a useful form of energy e.g. using wind turbines to create electricity.
In terms of electrical uses on a large-scale, wind farms are the key. These are a collection of many wind turbines to collect as much wind power from one geographically-viable area as possible. To make use of wind in a personal, or small-scale, way, the use of turbines and storage capacitors’ are the way forward. Wind Farms are connected to the electric power transmission network, whereas smaller facilities are used to provide electricity to isolated locations. Utility companies increasingly buy back surplus electricity produced by small domestic turbines.
As an alternative to fossil fuels, wind power has ample positive factors. It is plentiful, clean, renewable, widely distributed, and produces no greenhouse gas emissions during operation. However, the construction of wind farms/turbines has been frowned upon in some communities and areas, as it can have a large visual impact aesthetically. Yet, with some of the most viable areas for wind farming out to sea (and thus more wind farms being built at sea) this could be a small complaint of the future. Any effects on the environment, nevertheless, are generally among the least problematic of any power source, making it a favorite amongst the more environmentally friendly of you.
In a wind farm, individual turbines are interconnected with a medium voltage, power collection system and communications network. At a substation, this medium-voltage electric current is increased in voltage with a transformer for connection to the high voltage electric power transmission system.
In small scale wind energy generation, the surplus power produced by domestic micro generators can be fed into the network and sold to the utility company, producing a retail credit for the micro generators' owners to offset their energy costs. This works on a retail credit system, the same as that used in small scale solar power generation.
Wind turbines have been used for household electricity generation in conjunction with battery storage over many decades in remote areas. The diagram here shows the basics of what is needed in a turbine. Hub and Shaft provide support and stability; Blade, Gearbox and Generator provide the means to produce/take in the energy; and the Transformer takes the converted energy from the turbine.
There are several different ways to secure a wind turbine. Mounted on a suitable tower, using a ‘shelter model’ to predict how nearby obstacles will affect local wind conditions, or even installed on a roof. Installation issues then include the strength of the roof, vibration, and the turbulence caused by the roof ledge. Small-scale rooftop turbines suffer from turbulence and rarely generate significant amounts of power, especially in towns and cities.
Although this may be motivated by practical considerations (such as unreliable grid power or long distance from the grid) it is primarily used to describe the environmentally-conscious and their approaches to generating power that aspire to zero or low-carbon footprints.
Environmentally, studies have backed-up the environmental impacts of wind power on a small-scale in the UK. (A new study by the Carbon Trust into the potential of small-scale wind energy has found that small wind turbines could provide up to 0.4% of the total UK electricity consumption. This is saving 0.6 million tonnes of carbon dioxide emission.
It seems that wind turbines seem like a great idea for urban personal renewable energy, due to factors like; ease of installation, benefits to the environment and ability (in the right conditions) to easily (and effectively) produce electricity in many different environments, wind power will continue to be a popular source of personal renewable energy. However, as there is various issues with the technology and its suitability in various places, it may be best left to those in areas high above sea level, or in less densely populated urban areas, and of course the most environmentally conscious.
Article submitted by Carlo Ruggiero.
Carlo Ruggiero is a green aficionado who is passionate about getting the word out on renewable sources of energy and all things green, from funding your hot water to making money from your electric heating. You can follow his struggle with social media and daily musings on Twitter.