Ferranti: Power Generation and Transmission
Note: This is a sub-section of Ferranti
1894 Messrs S. Z. De Ferranti supplied alternators and other equipment for Portsmouth Electric Supply Works.
1897 After the move to Hollinwood, two major businesses were set up, one for production of meters, and the other for steam alternators, or generators attached to the flywheels of reciprocating engines.
1897 Equipment for the new Paisley generating station: 'These generators are being constructed for the Corporation by Messrs. S. Z. de Ferranti. Ltd., Hollinwood, and consist of what is technically known as fly-wheel alternators. The engines will be vertical compound, fitted with jet condensers, the fly-wheel being situated between the high pressure and low pressure cylinders. On the rim of the fly wheel will be mounted the copper coils forming the armature of the alternator, and these coils will revolve between the pole faces of powerful electro-magnets carried on a cast-iron casing which will entirely surround the fly wheel and armature. In all, three such steam alternators are on order, two having engines of 400 i.h.p. each and one of 200 i.h.p. Steam will provided by three water-tube boilers of the Babcock and Wilcox type. These will fitted with Vicars patent mechanical stokers. Two Frank Pearn & Company's Cameron type, compound boiler feed pumps will be employed, and the boiler feed will heated by a Green's Economiser. On a raised platform at the north end of the engine-room, the main switch-gear, which is of Messrs. Ferranti's standard type, will be erected, and from this point each generator and feeder main will controlled. The rectifier room above referred to will contain the apparatus for operating the arc lamps for street lighting, and the employment of rectifiers will enable the Corporation to secure all the advantages of direct current for arc lighting without the necessity of employing a separate generator. The rectifier will consist of a transformer which will convert alternating current at fixed pressure into constant current of variable pressure. The current from this transformer will pass through a commutator driven by an alternating current motor running in synchronism with the fly-wheel alternator. By an arrangement of brushes in contact with the commutator a current is led into the street lamps in one direction, whereas the current supplied by the transformer to the commutator changes its direction of flow 50 times per second. These rectifiers are an exceedingly ingenious piece of apparatus and are also being made by Messrs. Ferranti. Ltd.
The high pressure alternating current will conducted to the transformer chambers in the town by concentric cables, insulated with vulcanised bitumen, laid in cast-iron troughs. These troughs will also contain the cables for the street lighting. After the cables are in position, the troughs are filled solid with refined bitumen, and cast-iron cover will then placed over the whole. It will be seen that the high tension feeders and street lighting mains will be enclosed in a solid block of bitumen which is practically imperishable, and this constitutes the well-known "solid system" of Messrs. Callenders' Cable & Construction Company. Ltd., of London, to which firm the Corporation have entrusted the manufacture, laying, and equipment of the whole of the mains required for both public and private lighting. ....'
1900 Ferranti alternator commissioned at Cardiff Corporation's electricity works.. This was probably the 300 kW, 200 rpm 'steam alternator' advertised for sale by Cardiff Corporation Electricity Dept in 1924.
1901 The Ferranti company was incorporated
1901 400 kW alternator ordered by Wakefield Corporation 
1901 Ferranti Ltd was registered and acquired the whole of the undertakings and assets of S. Z. de Ferranti Ltd. which had equipped some of the early electricity generation stations.
1903 Supplied large engines to drive two generators for the temporary generating station of Tooting Tramways. The compound engines drove 1500 kW Dick, Kerr and Co alternators, and had HP and LP cylinders of 31" and 62" diameter respectively, 30" stroke. In addition engines for two 1500 kW alternators were being constructed by Ferranti in the London Electric Supply Corporation power station at Deptford.
1903 Ferranti Ltd was in financial difficulties (largely because of its activities in steam engines and dynamos). At the instigation of the debenture stockholders, the company went into voluntary receivership.
1904 Ferranti engine and alternator in service at Dover generating station. Still operating in 1930.
1905 After the reorganisation of the company, its focus was put on Switch Gear, Transformers and Instruments, areas where the Ferranti name was recognised a leader in the field, and no further work was taken on construction of generating stations. The future demand for high output generating plant would be met by high speed turbines and alternators, not by the relatively low speed engine-driven alternators favoured by Ferranti. (Note: The speeds were low compared with steam turbines, but the speed of Ferranti's engines was high compared with that of other large reciprocating engines. See below.
1909 Hanley Council electric lighting committee discussed problems affecting No. 6 alternator, supplied by Ferranti in 1897. There was a tendency for coils in the outside layers to come loose, and one had shorted. Examined by Mr Anderson of Ferranti.
1911 Switchgear (see advert)
WWI Manufacture of domestic appliances and switchgear ceased until after the war.
Ferranti Steam Engines
Ferranti favoured high speed engines in order to mimimise size for a given power output and to facilitate governing. A 2500 HP engine was operating at 150 rpm in 1896, and speeds of 214 and 240 rpm were mentioned in 1901. An engine installed at Wakefield in 1901 had a speed of 258 rpm. The engines had forced lubrication and were enclosed. Only two main bearings were used, and these were spherically-seated. 60 engines were built between 1896 and 1901. The best year was 1901, with 21 engines, total output 13,500 kW.
Sources of Information
- The Engineer, 22 Nov 1895
- Paisley & Renfrewshire Gazette - Saturday 31 July 1897
- South Wales Echo, 5 July 1900
- Western Mail, 2 June 1924
- Wakefield and West Riding Herald, 5 January 1901
- Kent & Sussex Courier - Friday 11 January 1901
-  The Engineer, 15 May 1903, p.493ff.
- Dover Express, 1 April 1904
- Staffordshire Sentinel - Wednesday 13 January 1909
- 'Power from Steam. A History of the Stationary Steam Engine' by Richard L. Hills, Cambridge University Press, 1989/1993