Renewable energy 
and savings

Modern societies consume huge amounts of energy for heating (homes and offices), transportation, electricity production and industrial use. Due to economic progress and a rising standard of living, the demand for energy is continually increasing. At present, the largest amount of energy we use is derived from conventional sources of energy which are petroleum, gasoline and coal. These are non renewable sources of energy which, sooner or later, will be exhausted. The production and use of energy derived from these sources create a series of environmental problems, the most serious of which, as we all know, is greenhouse effect.

On the other hand, renewable energy sources (RES) are continually renewed by the cycle of nature and are considered to be practically inexhaustible. The sun, wind, rivers, organic material such as wood and even household and agricultural waste are energy sources which are always available and are never exhausted. They are plentiful in our natural environment and they are the first sources of energy used by man, almost exclusively, until the beginning of the 20th century, when humankind turned to the intensive exploitation of coal and hydrocarbons. Today about 16% of global f inal energy consumption comes from renewables, with 10% coming from traditional biomass, which is mainly used for heating, and 3.4% from hydroelectricity. New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels) accounted for another 2.8% and are growing very rapidly. The share of renewables in electricity generation is around 19%, with 16% of global electricity coming from hydroelectricity and 3% from new renewables.

Wind power is growing at the rate of 30% annually, with a worldwide installed capacity of 198 gigawatts (GW) in 2010, and is widely used in Europe, Asia, and the United States. At the end of 2010, cumulative global photovoltaic (PV) installations surpassed 40 GW and PV power stations are popular in Germany and Spain. Solar thermal power stations operate in the USA and Spain, and the largest of these is the 354 megawatt (MW) SEGS power plant in the Mojave Desert. The world’s largest geothermal power installation is the Geysers in California, with a rated capacity of 750 MW. Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18% of the country’s automotive fuel. Ethanol fuel is also widely available in the USA.

Interest in the broader exploitation of RES, as well as in the development of reliable and economically profitable technologies to use their potential appeared, in the beginning, after the first oil crisis in 1979 and became permanent in the following decade after public awareness of global environmental problems. For many countries, RES are a significant energy source, with great development potential on a local and national level. RES make an important contribution to their energy balance, helping to reduce dependence on expensive and imported petroleum and strengthening the security of their energy supply. While many renewable energy projects are large-scale, renewable technologies are also suited to rural and remote areas, where energy is often crucial in human development and at the same time Small & Medium sized enterprises use the latest technological solutions in renewable energy utilization for cutting down their energy costs.