12th January 1882. Fossil Fuels or Nuclear? – AC or DC?
Coal-fired power stations, through the dispersal of fly-ash, pollute the environment with radioactive materials, which in nuclear power plants are extremely closely contained.
So the battle now is between fossil or nuclear power generation: initially it was between Direct or Alternating Current.
Coal was the main energy source which drove early electricity generation and it was Today in 1882 that saw The Holborn Viaduct, London illuminated with electric arc-lamps, from the world’s first public steam-driven power station.(1)
However the lighting depended on Edison’s Direct Current (DC), which proved to be a dead end for supplying electricity over long distances. Also the station used a reciprocating steam engine, soon to be replaced by the new Parson’s steam turbines.
Two years later the Station closed to be blamed on the 1882 Electricity Act, which gave Local Authorities power to prevent new systems from crossing boundaries. More importantly in the ‘battle of the currents’, Edison’s system was soon to yield to Alternating Current which was better over long distances.
In 1881 in Surrey, Godalming was using hydro-electric power and became the first town in Britain, to combine public and private use of DC current generated by water wheel power on the River Wey.(2)
However flooding made the water-wheel eventually unusable and the company was forced to use steam-power which had the effect of raising prices.
In March 1884 Siemen’s who had taken over from Calder and Barratt found a dearth of new subscribers, and the supply stopped in May 1884.
It was to be seventeen years before electricity returned to the town which now would have used both steam power and alternating current.
It was through the work of James Clark Maxwell and Oliver Heaviside which resulted in their Alternating Current (AC) theory being used in the public supply of electricity.
It was promoted by Westinghouse, and the London Electricity Supply Corporation which opened the first modern power AC station, designed by Ferranti, in Deptford. It resulted in a standardised power supply which was to culminate in the National Grid in 1926.
Though alternating current became the norm for long distance electricity supply, the widespread use of digital technology today requires the conversion of AC to DC, with all its implications for supply.
(1) Arc-lamps had the disadvantage of intense light and the carbon electrodes burnt out quickly. With the development of Swan’s incandescent lamps, arc-lights were superseded by the end of the 19thc century for street lights, but were kept for industrial use.
(2) It was on Friday 30th September 1881 that the town’s general purposes committee had agreed a contract with Calder and Barratt to light the streets at a cost of £195. Also the company agreed to sell electricity to the public, the first in the world to do so.
Thermal power stations, gas and coal, pump out carbon dioxide CO2 and NO2 (nitrogen dioxide) major air pollutants, so coal powered power stations are to be phased out to reach carbon emission targets of the EU in 2012. These are to be replaced by gas which is said to be not so polluting.
The concentration of radioactive isotopes of uranium and thorium is a problem for the coal-fired stations: a large 1000 megawatt (MW) coal fired plant which burns about 4m tons of coal a year has an unregulated release of 5.2 tons of uranium and 12.8 tons of thorium from a single coal plant, as well as radium, radon, polonium and potassium -40.
The complicated science in element decay, which is responsible for the dangerous radioactive release, is shown by thorium which decays to thorium 230 to radium 226 to radon 222 to polonium etc; thorium 228 has similar chain.
Radon is a gas which can have injurious health effects and is found in areas of granite rock especially Cornwall.
Ref: Oak Ridge National Labaratory art coal combustion: nuclear resources or Danger, Alex Gabberdss, WWW,ornl.gov/info/ornlreview/rev26-34/text.
Ref: engineeringtimelines.com. Pic Ref and data.
Ref: Electrification of Holborn: New Scientist 14th January, 1982. Vol 91, p730.
Ref: Power Station Wiki Ref; Electrification of Holborn, Jack Harris, 14 January 1982. New Scientist.
Ref: CEJournal.net Centre for environmental journalism.