Farnham U3A History Group

From Faraday to Ferranti The Development of Electrical Power

Part B Trevor Williams The • The Gallery was founded by Sir Coutts Lindsey in 1877and was a great success. At the Paris Exhibition of 1882 Lindsey was advised to install electric lighting and a small was built under the Gallery with 2 Siemens generators and 2 steam engines. The system was highly successful and neighbouring organisations asked to be connected. Some of these were quite distant: in The Strand and in , and the ensuing complication made the system unreliable. Ferranti was asked to advise on how the system could be improved. The Grosvenor Electrical System: • The Gauland and Gibbs a.c. electrical distribution system was probably the first devised. It was used in the Grosvenor Gallery and was patented in 1886. • Gauland (a Frenchman), designed a transformer based system using Faraday’s concept, with an a.c. power supply delivered to each customer connected to the system via a transformer. • Power recipients connected their loads side by side to their transformer outlet but the transformers were connected to the generator one after another in a daisy chain sequence. • Ferranti redesigned the system with side by side transformers and more powerful generators. The system worked well and encouraged the proprietors to consider a much larger system. The Gauland and Gibbs Electrical Power System. The Electric Supply Corporation 1887. • This was formed out of the Grosvenor System in the expectation that the availability of a supply of electricity would result in a considerable demand • Ferranti was appointed Chief Engineer and Electrician and was asked to propose a system that could satisfy this requirement • In the USA, Edison had built a system with local generating stations supplying ‘safe’ low voltage dc. • Ferranti decided to go for the improved Gauland system with a single power station outside the conurbation to supply the needs of the whole of London at that time. Electricity would be delivered as high voltage ac with local transformers to step the voltage down to a safe level. Ferranti’s Proposals. • Later work has shown that an a.c. power supply system can be much more complicated than a d.c. system but for simple loads, such as lighting and heating, it behaves much like a d.c. system. • For Ferranti, the use of high voltage distribution reduced the current and hence the resistance losses to give a high efficiency system. For a man of 24 years his proposal was incredibly ambitious: Ferranti’s Proposed Distribution System Power Station to Distributing Stations - 10kV Distributing Stations to Street Sub-Stations - 2.4kV Street Sub-Stations to Houses - 100V Frequency 83.33 Hz or 5,000 cycles/minute. Power Station. • The LESC accepted Ferranti’s proposals. A site for the power station was found at Deptford about 8 miles from the city, close to Deptford Creek and adjacent to the Thames. could be delivered by boat and water drawn from the river. The HV cable was to run beside the London and Greenwich Railway line. : A single generating unit showing a generator, belt (rope?) driven, from a Musgrove steam engine. The Assembly of a 7.5MW Ferranti Alternator There were 4 alternators each driven by a 10,000 hp reciprocating steam engine at 60 rpm Output of 750 A at 10 kV. Weight 500 tons. Ferranti Transformers: Used to reduce the voltage from the 10 kV cable to the 2.4 kV distribution voltage and to reduce the 2.4 kV to the 100V required for the street sub- stations.. Ferranti’s High Voltage Cable:

• The inner copper tube formed the high voltage conductor: the insulation was made up of layers of waxed paper and the copper-paper assembly was pushed into the outer copper tube. The outer tube was then swaged to hold the insulation in position. • The cable was made up in 20 ft lengths which were protected in wrought iron pipes. • The outer copper tube provided the return path for the current and was earthed for public safety. In 1933 some of this cable was still in use. Safety Test on the 10kV Cable : With H.W.Kolle, Ferranti’s PA holding the spike ! The 1889 Marindin Report to the Board of Trade • While the LESC and Ferranti had been pursuing Ferranti’s proposals, many small electricity businesses had sprung up supplying electricity to localities in London and elsewhere in the country • Major Francis Marindin R E had joined the Board of Trade and he was asked to review the situation and make recommendations for future policy. Major Marindin was the Army expert on Rail Transport. He had been used previously to provide expert technical advice and he was very highly regarded. He later received a knighthood for his work. Marindin’s Conclusions. • To ensure proper coordination it was decided that Supply companies should apply for licences and that these should be awarded for specific supply areas. • In London there were now over 30 supply companies and the area awarded to the LESC was insufficient to justify the planned expansion. • Marindin approved of the company’s organisation but it seems likely that he had doubts about the safety and security of the high voltage circuits. • This effectively doomed Ferranti’s development programme which had been designed to provide a large scale efficient and economical energy supply. • Ferranti lost his job and the LESC system was redesigned and rebuilt for its reduced requirement. Technical Development in the following years: • With the rapid increase in the demand for a supply of electricity the technology also developed rapidly. • High speed steam turbines replaced reciprocating engines and generators were redesigned for the higher speeds. • Tesla invented the induction motor and devised multiphase ac systems: first available in Newcastle in 1901. • 3 phase 132kV became the standard for long distance power distribution with air insulated conductors. Organisational Developments • By 1900, there were 625 power supply companies in the UK and London alone had 70 generating stations. • The Government passed a series of Acts to try to rationalise and standardise the power supply situation. • The Electricity (Supply) Act of 1919 appointed Commissioners to establish Joint Electricity Authorities and in due course to establish a Central Electricity Board to institute a 132 kV National Grid. • It was not until Nationalisation in 1948 that all the 625 power supply companies were brought under a single organisation, ‘The British Electricity Authority’. This and the ‘Central Electricity Generating Board’ disappeared under the arrangements for Privatisation. Ferranti’s Achievements and Later Life He established a manufacturing business with 20,000 employees in Lancashire producing electrical machines, switchgear and power metering equipment. He made 176 patented inventions. Honours: Hon. D Sc. and FRS President: Institution of Electrical Engineers 1910 - 1913 “He was an Engineer, in the finest tradition of that profession, whose practitioners always face the stern discipline of making their ideas work.”