The renewable energy sources, derived principally from the enormous power of the sunâ€™s radiation, are at once the most ancient and the most modern forms of energy used by humanity.
We've used the Sun for drying clothes and food for thousands of years, but only recently have we been able to use it for generating power. In fact, solar power both in the form of direct solar radiation and in indirect forms such as bio energy, water or wind power was the energy source upon which early human societies were based. When our ancestors first used fire, they were harnessing the power of photosynthesis, the solar-driven process by which plants are created from water and atmospheric carbon dioxide.
Photovoltaics (PVs) convert sunlight into electricity. They are made from silicon, the second most abundant element in the Earth's crust. The cells are fitted in panels to the exterior of buildings and are clean, safe and silent in operation. Although at the moment they are an expensive method of generating electricity for the grid, they compete very successfully with conventional systems for a wide range of applications in remote locations, and are being used more and more in the developing world. For example, solar cells provide power for refrigeration and water pumping in hot desert regions, and for telecommunication equipment on mountain tops.
The most important issue with solar panels is capital cost. Newer alternatives to the standard crystalline silicon modules are creating more efficient panels. Due to economies of scale, solar panels get less costly as people use and buy more. In fact, as manufacturers increase production to meet demand, the cost and price is expected to drop in the years to come.
The use of wind turbines can be a great way to provide a source of clean and renewable energy for your home or business. There are a number of small wind energy devices that you can use to generate power, and most of these are very cost effective in providing a substantial level of electricity. Wind turbines use the wind's lift forces to rotate aerodynamic blades that turn a rotor which creates electricity.
Some believe that to make a substantial change one has to invest thousands of Euro, yet many underestimate the results brought about by more efficient use of resources.
Installing alternative energy generators such as Photovoltaic panels, at a substantial cost, before assessing the current efficiency (or lack of) patterns could easily be considered a waste of money and resources as the clean energy generated will only be used to compensate for the current inefficiencies.
In this section we will focus on specific ways on how to reduce the inefficiencies in a household. Cutting these inefficiencies could be the first step towards a reduction in emissions with substantial impacts on a national level.