Basically, the ‘Green Energy’ idea is how our everyday needs are supplied by natural resources such as wind, tides and even geothermal heat. They are considered ‘Green’ because they are environmentally friendly. It’s interesting to note that in some instances we’re actually travelling back in time to utilise some of the older energy skill sets e.g. Wind Power (Windmills etc.) But in the main, this is the process of utilising modern technology to provide eco-efficient and planet-friendly alternatives.
In the home environment, one can see examples such as Solar Thermal and Solar Water Heating Collectors. To gain electricity from roof panels you would need solar electrical panels (PV’s). Following on from this is a process known as Biomass Energy – which includes Boilers burning wood and other fuels. We now also have Ground Source Heat Pumps – which draw out the heat left by the Sun. Finally, we have two of the most traditional forms of energy generation that have gone through some resurgence over the last few years; these being Wind Power, Wind Turbines and Hydropower (including Water Wheels.)
solar energy Systems: Also known as Solar Energy, this mainly uses two, albeit different types of solar panels to get the desired results. Initially, there is the process of obtaining hot water from the Sun via Solar Water Heating Collectors. Furthermore, there are the Solar Electrical Panels (more correctly known as Photovoltaic heat collectors) which transform solar radiation into electricity. Obviously situated away from blockages such as chimneys etc., these Solar Panels need to be mounted on south facing roofs at an angle of 30 degrees from the horizontal.
In the UK, Solar Water Power is now one of the most sought after forms of Solar Energy. With the ability to provide almost half the annual need for hot water in the house, Solar Water heating systems are very important. The cost of fitting depends on whether you do it yourself (500 to 1500 pounds) or whether you get a professional fitter – in which case it will cost between 2-5k overall.
Biomass Energy Based Systems: Historically, this has come from plants and animals, though nowadays this also includes new genetcially engineered ‘energy crops’. Considering its ability to produce energy in the form of heat and electricity, this type of energy is extremely flexible. Furthermore, within the European Markets, the UK is one of the central producers of Biomass fuels. Considering all this, and the relative lack of C02 produced, makes the whole process highly green overall. Much of the UK wood crop is sustainable, in order to ensure that C02 produced during any heating process is absorbed.
Within this field is the need for the use of ‘Energy Crops’, such as fast growing trees, e.g. Willow and Poplar or other entities grown on a Short Rotation Coppice (SRC). Also producing high yields of dry matter are the perennial grasses. Equally significant within this practice sit Municipal and Agricultural waste products. To begin with, Agricultural Waste is often produced as part of the agricultural process overall. However, waste derived from food or wood is another biomass entity – called Municipal Waste.
Systems Based On Geo-Thermal Energy: Used in the generation of both warm water and electricity, this energy mainly comes from the Sun and heats the Earth. Using the ground temperature of around 12 degrees in the UK – we can both heat and cool buildings. Generally, items such as Heat Pumps are thought of as very effective, as they produce four units of energy for every one that is used for generation. A greate return of energy (sometimes almost 100 percent) is produced – because heat source pumps can operate in-line with wind turbines and solar electrical panels.
Wind Energy: The use of wind as a source of energy has been going on for thousands of years, especially in milling grain and pumping water. However, in more recent times there’s been the option to recover the energy for its own sake – and deliver this either to a home unit or to the local power grid. The UK is considered as one of the best sources of wind generation within Europe. It is interesting to note that whilst we can produce 10 percent of our entire power requirement from wind power, at present we only produce 1 percent. Instead of producing electricity at a rate of 2-10p per kWh, we could be generating at 2p per kWh. From this, the estimation of the cost recovery period is around 6-9 months overall.
Hydropower is a method that suits the UK energy production system. The field of using moving water to release energy is a very old technique – albeit we now do this in new ways. It is this type of energy production that could meet 2 percent of all the UK’s demand.
By using a turbine, a Hydropower system can transfer the kinetic energy of moving water into another form. By using a dam or a natural river drop, these turbines do not require water storage. ‘Micro-Hydro’ however, uses the dam and sluice systems that have been made redundant by the larger national distributions. Although a lesser known form of electricity output, this process could supply 200mW of UK demand. A micro-hydro system like this would be expected to cost between 200 and 3,000 pounds per kW of the energy.
‘Green Energy’ is growing – mainly due to the demands of the Western World. That said, the UK is well placed – especially in the domestic sector – to take full advantage of the items above.
With the rise in demand for domestic installations, both Electricians and Plumbers are well placed to take advantage of this technology. With ‘Green Energy’ rising up the political agenda in Europe, a range of financial aids and grants are becoming available. It is important to gain the correct qualifications to install these items. Electrical or plumbing training that incorporates green technology could be very useful for the future.
(C) S. Edwards 2009. Check out Solar Energy Courses or Solar Energy Training.