Power Systems, national grid

The power required for electrochemical processes motor drives, lighting, and general use, may be generated on site, but will more usually be purchased from the local supply company (the national grid system in the UK). The economics of power generation on site are discussed by Caudle (1975). 

In a power station, the turbine drives a generator to produce electricity which is then fed into the national grid (Figure 6.10). The national grid is a system for distributing electricity throughout a country. 

In 2008, SuperPower, Inc., an electric power component manufacturer in Schenectady, New York, produced a 1,311 meter (.814 mile) length of HTS wire, a new record for the industry. SuperPower recently completed the Albany Cable Project in which a 350 meter (1,148 feet) HTS underground cable was installed in the National Grid power system connecting two substations in Albany, New York. 

Electricity is taken from the National Grid by appropriately located substations which eventually transform the voltage down to 11 kV at a local substation. At the local substation the neutral conductor is formed for single-phase domestic supplies and three-phase supplies to shops, offices and garages. These supplies are usually underground radial supplies from the local substation, but in rural areas we still see transformers and overhead lines suspended on wooden poles. Figures 3.11 and 3.12 give an overview of the system from power-station to consumer. 

Individual onshore turbines are interconnected with a medium voltage (usually 34.5 kV) power collection system and communications network by underground cables. At a substation, the medium-voltage electrical current is increased in voltage via a transformer for connection to the high-voltage National Grid system. 

Hydropower provides an essential contribution to the national power grid its capability to respond in seconds to large and rapidly varying loads, which other baseload plants with steam systems powered by combustion or nuclear processes cannot accommodate. Also, ownership is spread over a broad base. The owners comprise federal and state agencies, cities, metropolitan water districts, irrigation companies, and public and independent utilities. Individual persons also own small plants at remote sites for their own eneigy needs and for sale to utilities... 

Beaver, C. L., D.R. Gallup, W.D. NeuMann, and M.D. Torgerson, Key management for SCAD A, Scandia National Laboratories, March 2002, Security Aspects and requirements of the Supervisory Control and data Acquisition System, for the Electric Power Grid... 

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