Energy supply

With power supply to consumers is referred to useful energy in business and technology.

The energy in question forms and carriers on the one hand Conducted energy like electricity or liquid or gaseous fuels such as natural gas or gas transmission and district heating, on the other hand solid fuels such as coal, coke or wood. More significant is the future of energy supply from renewable energy, as the sun, wind and water power as opposed to fossil fuels are perpetual and have no available primary energy costs.

• 4.1 Electrical Energy
• 4.2 Other sources of energy

Term

In a broader sense, especially in the designation as an economic sector ( for example according to NACE), the term energy supply includes all energy sources and the entire value chain, from the development of energy sources to distribution to end users. In this broad meaning the area is also known as energy beings.

When used in a narrower sense, only the last portion of the chain with the distribution and direct supply to end users ( "last mile " ) with grid-based energy carriers such as ( Electricity, mains gas, district heating) meant is often ( also English "downstream " called ). Not counting here is the upstream extraction of energy resources (eg coal and lignite mining, oil and gas extraction, also called English "upstream "), whose long-distance transport, storage and processing ( eg, operation of oil and gas pipelines or refineries, also called english " midstream ") and the non- wired distribution of solid and liquid fuels.

The power supply in biological systems is described in each case by the energy metabolism of the organism in question. The case most frequently used form of energy is sugar, the universal, chemical, decentralized and sustainable natural storage for solar energy, build the plants in photosynthesis. Animal organisms nourish their anabolism energetically with sugar and higher organized, originally hervorgegangenem of sugar, organic material. As custodian to compensate for gaps in coverage serves fat. This aspect is not considered further in this article.

History

With the beginning of the use of fire in the history of mankind the power was shared by collecting firewood than it was then the sole energy source. With the formation of settlements, towns and industrial centers of trade and the supply became more and more important with fuels such as wood, coal, train oil, and later oil, natural gas and electrical energy. In industrially developed countries, companies have dealt with the provision of technically easily usable and economically excellent controllable energy for general consumption since the 19th century. This is the most affordable and reliable generation of electrical energy as well as transmission to the individual consumer to the fore. Furthermore, the procurement, transport and transformation of fuel for heating purposes is a major industry.

The world energy demand is a statistical value of sales of all energy supply companies. He has risen significantly in recent years and decades. It says nothing about how to change by the transformation processes ecosystems. Is foreseeable, however, that with the present ( 2012) as practiced handling and consumption of energy is not the entire world population can serve as practiced on the level of the developed countries.

Energy sources

The main source of energy is nuclear fusion, which takes place in the sun and its energy arrives as electromagnetic radiation on earth. By converting processes arise from this sunlight other forms of energy such as biomass, wind energy, water energy and fossil fuels in the long term. The use of renewable energies is primarily based directly or indirectly on this sunlight.

An independent from the sunlight energy source are radioactive decay processes within the Earth, which are the major source of energy in the use of geothermal energy. A nuclear power plant also uses the artificially induced fission of atomic nuclei as an energy source.

Another source of energy is the Earth's rotation, the energy can be used in tidal power plants due to its associated effects ( tides ).

Fossil energy sources

The chemical bond energy of organic, carbon-containing substances can be very easily converted into thermal energy by burning. The most highly available and easily verheizbaren with little technical effort materials are hydrocarbons that originate from the initial sugars of carbon assimilation phototrophic plants. The density of the released during complete combustion energy per kilogram of starting material is satisfactory for fossil hydrocarbons. So, fossil fuels are a type of fuel concentrate from prehistoric biomaterials, thus becoming the preferred primary sources of energy supply.

With the use of fossil fuels such as oil or coal, the greenhouse gas carbon dioxide is released in large quantities, which contributes to global warming.

Renewable Energy

The energy contained in sunlight, the wind, the Earth's mantle and the water can be used with the help of renewable energy. This is done by wind turbines, photovoltaic and solar thermal systems, geothermal power plants, hydroelectric power plants and the use of biomass. While hydroelectric power is a used for a long time technology that is at the other technologies such as photovoltaics or power generation using wind energy are relatively new ways of energy conversion, the increasingly used only since the 1980s and 1990s, however, high growth rates have. They are encouraged in many countries with regard to environmental and climate protection and their CO2 neutrality.

Wood and other biomass energy as a carrier, shall, use of solar energy renewable carbon compounds are dried and then still have a lower specific heating value when the fraction products of the petroleum industry. The generation of energy sources (biogas and biofuel ) for the purpose of energy supply in economically relevant scale is not without problems, as you can see the tension between the food supply and nature and landscape protection.

Nuclear fission

The heat generated in nuclear reactors by the fission of heavy nuclei such as uranium and plutonium thermal energy is used to evaporate water and thus drive turbines, then the - generate electricity generators - as in all other thermal power plants also. Thus, electrical energy without the emission of greenhouse gases such as CO2 are obtained, however, radioactive wastes, their disposal has not yet been explained.

The Chernobyl disaster has the acceptance of nuclear power plants and a lot of damage done in some countries such as Italy to phase out this type of energy. Other countries such as France have not let that influence.

In Sweden in 1979, successfully conducted a referendum against nuclear energy. The subsequent decision of Parliament to build no further nuclear power plants more and the four existing off to 2000, was revised on February 5, 2009: The ban on new reactor construction adopted in 1980 is repealed. The ten Swedish nuclear reactors may be renewed and extended. Even after the Fukushima nuclear disaster Sweden holds firmly to the use of nuclear energy. Germany plans a complete phase-out of nuclear power by 2022.

Energy sources

The " raw energy " energy sources such as oil and uranium is almost never used without prior conversion and is therefore always first converted into transportable and storable energy carrier. Only in this way can a comprehensive energy supply to be created.

Electric Power

The most versatile form of energy is the electric power based on the power supply. Electrical energy can be converted with very low losses in all other types of energy and thus has gained a dominant position worldwide. The exceptionally universal usability of the electric energy is reflected in the wide availability of transducers, the electrical energy into heat energy ( electric heating), kinetic energy (motor), light energy (light source ), sound energy (speaker), electromagnetic waves ( radio transmitter ), chemical forms of energy convert (electrolysis ) or potential energy ( electromagnet).

Main disadvantage of the electrical energy is their limited storability. You can indeed save in small amounts in capacitors, for significant amounts of energy but lossy detours via other types of energy in batteries, pumped storage or compressed air storage are required. Other energy storage such as hydrogen or flywheels are, however, currently used only for relatively small amounts of energy (see energy storage ). The storage capacity of the German natural gas network for hydrogen is more than 200,000 GWh and can temporarily store the energy needs of several months. For comparison, the capacity of all German pumped storage plants is, however, only 40 GWh. The natural gas system is suitable for the absorption of hydrogen. The memory requirements of a future electricity supply in Germany, which is based 80% on wind power and photovoltaic systems is estimated at 30,000 GWh and would thus already to cover easily through the existing gas storage. The also occasionally suggested storage of large amounts of energy to compensate for fluctuations in the power supply in the whole of Europe with pumped-storage power plants in Scandinavia and the Alps is not feasible with the current power grids. Because of the high losses incurred over long distances in alternating current transmission, would have to first superimposed the current high voltage grid with 420 kV by one with about 1250 kV or a high-voltage direct current (HVDC ) can be built.

Other sources of energy

Construction, operation and maintenance of electrical transmission networks and the electrical transmission losses cost money. Therefore, in the siting of power plants absolutely necessary to check whether away into electrical energy from the place of consumption, the conversion is done (use- distant generation ) and is then transmitted. Sometimes it is more economical, liquid or gaseous fuels such as oil, natural gas, industrial gas, district heating and district heating to transport via pipelines ( pipeline ) and to build power plants directly where the electrical power is needed ( distributed generation ).

The distribution of solids such as coal and wood or small quantities of fuel oil and fuel ( gasoline and diesel ) by truck.

Energy storage

For the change to renewable energy sources of sufficient capacity energy storage must be built. For this long-term goal, there is currently still no proven and economical solution. Great importance as a long-term memory is granted the power-to - gas technology, from the far (as of 2013), however, are only a number of test systems in operation. For storing small amounts of electricity over hours and days pumped storage power plants are available. For residential and commercial buildings exist heat storage in which recovered during the warm season, solar thermal energy can be stored, so that must be only slightly been heated during the winter months (see also: sun house). The storage of fossil fuels such as natural gas or oil for seasonal balancing is handled with underground storage.

Energy supply companies

Power companies are companies that provide as part of universal service, supply of household and commercial energy in the form of electricity, mains gas and / or district heating.

In Germany energy company primarily municipal public utilities and regional subsidiary of the large control area operator.

Power company i.S.v. § 3 No. 18 of the Energy Act are " natural or legal persons, the energy supply to others, operate a power grid or to have a power supply network as the owner of disposal; the operation of a client facility or a customer system for occupational self-sufficiency makes the operator is not the power company. "