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GRID CONNECTION Introduction It was in London in 1882 that the Edison Company first produced electricity centrally that could be delivered to customers via a distribution network or grid. Since then electricity has become one of the commonest energy sources for domestic use in the West. Electricity is extremely versatile, clean, easy to use, and can be turned on or off at the flick of a switch. Electricity has brought enormous social benefits in all areas of life. It is the preferred method of supplying power for many household applications, especially lighting, but connection to the national electrical grid is a rare occurrence in rural areas of the developing and under developed world. In the majority of the worlds poorer countries it is estimated that significantly less than 5% of the rural population are connected to the national grid. There are many reasons, both technical and economic, which make grid connection unfeasible and these will be looked at briefly in this fact sheet. In urban areas of the developing world grid connection is commonplace. There are other possibilities for providing electricity in rural areas. In many areas where electricity is required and there is no grid within easy reach then a localised grid (or micro-grid) can be established using a local power source such as a diesel generator set or small-scale hydro power scheme. Alternatively, individual households can be connected to stand-alone systems which can be powered by any of a wide variety of energy sources.  
GRID CONNECTION Introduction It was in London in 1882 that the Edison Company first produced electricity centrally that could be delivered to customers via a distribution network or grid. Since then electricity has become one of the commonest energy sources for domestic use in the West. Electricity is extremely versatile, clean, easy to use, and can be turned on or off at the flick of a switch. Electricity has brought enormous social benefits in all areas of life. It is the preferred method of supplying power for many household applications, especially lighting, but connection to the national electrical grid is a rare occurrence in rural areas of the developing and under developed world. In the majority of the worlds poorer countries it is estimated that significantly less than 5% of the rural population are connected to the national grid. There are many reasons, both technical and economic, which make grid connection unfeasible and these will be looked at briefly in this fact sheet. In urban areas of the developing world grid connection is commonplace. There are other possibilities for providing electricity in rural areas. In many areas where electricity is required and there is no grid within easy reach then a localised grid (or micro-grid) can be established using a local power source such as a diesel generator set or small-scale hydro power scheme. Alternatively, individual households can be connected to stand-alone systems which can be powered by any of a wide variety of energy sources.  
==Technical==
==Technical==
The Grid The national grid is a network of power lines which allows distribution of electricity throughout all or part of a country. The grid can be connected to a single power source or electricity generating plant but is usually linked with other plants to provide a more flexible and reliable network. The electricity is usually transmitted at very high voltage, typically several hundred thousand volts (depending on power transmitted, national guidelines, etc.) as this reduces losses and means that smaller cables can be used, reducing the overall cost of the network. Bulk electricity is generated and transmitted in 3 phase, alternating current (a.c. - 50 or 60 cycles per second) form and distributed to the consumer as three phase or single phase depending on the end use requirements. Transmission by direct current (d.c.) is also used, losses associated with d.c. electricity being lower than a.c., but other costs are incurred as heavy duty rectification equipment is then needed to supply a.c. electricity to the consumer. After generation, the voltage has to be stepped up (to a high voltage) for transmission and distribution using a transformer and then stepped down (to a lower voltage) for end use, again requiring a transformer. The step down process is usually done in several stages as the network is reduced in capacity. Typical consumer voltage is 210V or 415 V for three-phase and 120 V or 220 V for single phase depending on national standards. Three-phase electricity is used for higher power equipment such as factory or workshop machinery whereas all domestic electricity supply is single phase. Electricity production Electricity is most commonly produced by converting an energy source into mechanical shaft power, which in turn drives a generator which produces electricity. The energy source can vary depending on the available resources. Typical sources include fossil fuels, nuclear fuels (rarely in the developing world), hydro power (a selection of countries producing a significant proportion of total electricity from hydro power; Kenya 63%, Zimbabwe 37%, Peru 48%), [[solar power]], wind power, geothermal, etc. Traditional thermal power generation uses oil, coal or gas to produce heat which in turn is used to create steam which drives a steam turbine. The turbine provides the mechanical power for the generator. Similarly, nuclear power generation uses nuclear fuels such as uranium, which undergo a process known as nuclear fission in a reactor, to provide heat to drive the turbine. Hydropower (which is a very popular source of power in  
The Grid The national grid is a network of power lines which allows distribution of electricity throughout all or part of a country. The grid can be connected to a single power source or electricity generating plant but is usually linked with other plants to provide a more flexible and reliable network. The electricity is usually transmitted at very high voltage, typically several hundred thousand volts (depending on power transmitted, national guidelines, etc.) as this reduces losses and means that smaller cables can be used, reducing the overall cost of the network. Bulk electricity is generated and transmitted in 3 phase, alternating current (a.c. - 50 or 60 cycles per second) form and distributed to the consumer as three phase or single phase depending on the end use requirements. Transmission by direct current (d.c.) is also used, losses associated with d.c. electricity being lower than a.c., but other costs are incurred as heavy duty rectification equipment is then needed to supply a.c. electricity to the consumer. After generation, the voltage has to be stepped up (to a high voltage) for transmission and distribution using a transformer and then stepped down (to a lower voltage) for end use, again requiring a transformer. The step down process is usually done in several stages as the network is reduced in capacity. Typical consumer voltage is 210V or 415 V for three-phase and 120 V or 220 V for single phase depending on national standards. Three-phase electricity is used for higher power equipment such as factory or workshop machinery whereas all domestic electricity supply is single phase. Electricity production Electricity is most commonly produced by converting an energy source into mechanical shaft power, which in turn drives a generator which produces electricity. The energy source can vary depending on the available resources. Typical sources include fossil fuels, nuclear fuels (rarely in the developing world), hydro power (a selection of countries producing a significant proportion of total electricity from hydro power; Kenya 63%, Zimbabwe 37%, Peru 48%), solar power, wind power, geothermal, etc. Traditional thermal power generation uses oil, coal or gas to produce heat which in turn is used to create steam which drives a steam turbine. The turbine provides the mechanical power for the generator. Similarly, nuclear power generation uses nuclear fuels such as uranium, which undergo a process known as nuclear fission in a reactor, to provide heat to drive the turbine. Hydropower (which is a very popular source of power in  
Grid Connection  regions where the hydrological and site conditions permit and /or fossil fuels are scarce) uses the stored or potential energy of water which has a head or height above a certain point. The water is dropped through a turbine which provides shaft power for directly driving a generator. Windpower uses a similar principle but the energy is extracted from the wind to drive the turbine. Geothermal energy is heat energy stored in the earths crust which can be tapped to heat water for driving a turbine. Solar energy for providing electricity can be derived using one of two methods. Heat from the sun can be concentrated to drive a steam turbine, or the more popular method uses the photovoltaic principle to convert sunlight directly into electricity. Solar and wind technologies are not used on a widespread basis for producing electricity which is fed into large grid systems, though examples do exist.  The grid can be owned privately or by the state and is not necessarily owned by the electricity producer. The type of fuel source which will be used to provide electricity is dependent upon several factors. These include the following:  a countrys fossil fuel resources  cost of importing fossil fuels  government energy policy  availability of sites for exploitation of [[renewable energy]] sources e.g. large rivers, dams or lakes for hydro power  technical expertise available in country Cost of Grid Connection There are many constraints to rural grid based electrification. Firstly there is the question of cost. The cost of grid connection is influenced by the voltage and proximity of the grid and whether there is a step down transformer already serving the area in question. Capital cost of the distribution system is very high and demand in rural areas is very low. Households can be widely dispersed and often rural consumers will want to use only a few light bulbs and a radio in the evening. The cost-benefit relationship shows that there is little incentive for an electricity producing utility to extend the grid into remote rural areas. Often rural regional centres will be electrified but the network will usually stop there or bypass the remoter villagers as high voltage cables passing overhead. The figure below shows the cost of grid connections in relation to load density in rural and urban areas. In poorer communities the cost of house wiring, appliance purchase and electricity prices can also be prohibitive  
Grid Connection  regions where the hydrological and site conditions permit and /or fossil fuels are scarce) uses the stored or potential energy of water which has a head or height above a certain point. The water is dropped through a turbine which provides shaft power for directly driving a generator. Windpower uses a similar principle but the energy is extracted from the wind to drive the turbine. Geothermal energy is heat energy stored in the earths crust which can be tapped to heat water for driving a turbine. Solar energy for providing electricity can be derived using one of two methods. Heat from the sun can be concentrated to drive a steam turbine, or the more popular method uses the photovoltaic principle to convert sunlight directly into electricity. Solar and wind technologies are not used on a widespread basis for producing electricity which is fed into large grid systems, though examples do exist.  The grid can be owned privately or by the state and is not necessarily owned by the electricity producer. The type of fuel source which will be used to provide electricity is dependent upon several factors. These include the following:  a countrys fossil fuel resources  cost of importing fossil fuels  government energy policy  availability of sites for exploitation of [[renewable energy]] sources e.g. large rivers, dams or lakes for hydro power  technical expertise available in country Cost of Grid Connection There are many constraints to rural grid based electrification. Firstly there is the question of cost. The cost of grid connection is influenced by the voltage and proximity of the grid and whether there is a step down transformer already serving the area in question. Capital cost of the distribution system is very high and demand in rural areas is very low. Households can be widely dispersed and often rural consumers will want to use only a few light bulbs and a radio in the evening. The cost-benefit relationship shows that there is little incentive for an electricity producing utility to extend the grid into remote rural areas. Often rural regional centres will be electrified but the network will usually stop there or bypass the remoter villagers as high voltage cables passing overhead. The figure below shows the cost of grid connections in relation to load density in rural and urban areas. In poorer communities the cost of house wiring, appliance purchase and electricity prices can also be prohibitive  
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