Hydraulic power network

The first practical installation which supplied hydraulic power to the public was in Kingston upon Hull, in England. The Hull Hydraulic Power Company began operation in 1876. They had 2.5 miles (4.0 km) of pipes, which were up to 6 inches (150 mm) in diameter, and ran along the west bank of the River Hull from Sculcoates bridge to its junction with the Humber. The pumping station was near the north end of the pipeline, on Machell Street, near the disused Scott Street bascule bridge, which was powered hydraulically. There was an accumulator at Machell Street, and another one much nearer the Humber, on the corner of Grimsby Lane. Special provision was made where the pressure main passed under the entrance to Queens Dock.[4] By 1895, pumps rated at 250 hp (190 kW) pumped some 500,000 imperial gallons (2,300 m³) of water into the system each week, and 58 machines were connected to it. The working pressure was 700 psi (48 bar), and the water was used to operate cranes, dock gates, and a variety of other machinery connected with ships and shipbuilding. The Hull system lasted until the 1940s, when the systematic bombing of the city during the Second World War led to the destruction of much of the infrastructure,[5] and the company was wound up in 1947,[6] when Mr F J Haswell, who had been the manager and engineer since 1904, retired.[7]

The man responsible for the Hull system was Edward B. Ellington, who had risen to become the managing director of the Hydraulic Engineering Company, based in Chester, since first joining it in 1869. At the time of its installation, such a scheme seemed like "a leap in the dark", according to R. H. Tweddell writing in 1895, but despite a lack of enthusiasm for the scheme, Ellington pushed ahead and used it as a test bed for both the mechanical and the commercial aspects of the idea. He was eventually involved on some level in most of the hydraulic power networks of Britain. The success of such systems led to them being installed in places as far away as Antwerp in Belgium, Melbourne and Sydney in Australia, and Buenos Aires in Argentina.[8]

Independent hydraulic power networks were also installed at Hull's docks - both the Albert Dock (1869), and Alexandra Dock (1885) installed hydraulic generating stations and accumulators.[9]

The best-known public hydraulic network was the citywide network of the London Hydraulic Power Company. This was formed in 1882, as the General Hydraulic Power Company, with Ellington as the consulting engineer. By the following year another enterprise, the Wharves and Warehouses Steam Power and Hydraulic Pressure Company, had begun to operate, with 7 miles (11 km) of pressure mains on both sides of the River Thames. These supplied cranes, dock gates, and other heavy machinery. Under the terms of an Act of Parliament obtained in 1884, the two companies amalgamated to become the London Hydraulic Power Company. Initially supplying 17.75 million gallons (80.7 megalitres) of high-pressure water each day, this had risen to 1,650 million gallons (7,500 megalitres) by 1927, when the company was powering around 8,000 machines from the supply. They maintained 184 miles (296 km) of mains at 700 psi (48 bar), which covered an area reaching Pentonville in the north, Limehouse in the east, Nine Elms and Bermondsey in the south and Earls Court and Notting Hill in the west.[10]

The preserved pumping equipment in Wapping pumping station, which was owned by the London Hydraulic Power Company

Five pumping stations kept the mains pressurised, assisted by accumulators. The original station was at Falcon Wharf, Bankside, but this was replaced by four stations at Wapping, Rotherhithe, Grosvenor Road in Pimlico and City Road in Clerkenwell. A fifth station at East India Docks was originally operated by the Port of London Authority, but was taken over and connected to the system. The stations used steam engines until 1953, when Grosvenor Road station was converted to use electric motors, and following the success of this project, the other four were also converted. The electric motors allowed much smaller accumulators to be used, since they were then only controlling the pressure and flow, rather than storing power. While the network supplied lifts, cranes and dockgates, it also powered the cabaret platform at the Savoy Hotel, and from 1937, the 720-tonne three-section central floor at the Earls Court Exhibition Centre, which could be raised or lowered relative to the main floor to convert between a swimming pool and an exhibition hall.[11][12] The London system contracted during the Second World War, due to the destruction of customers' machinery and premises. Following the hostilities, large areas of London were reconstructed, and the re-routing of pressure mains was much more difficult than the provision of an electric supply, so that by 1954 the number of machines had fallen to 4,286.[5] The company was wound up in 1977.

A system began operating in Liverpool in 1888.[13] It was an offshoot of the London-based General Hydraulic Power Company, and was authorised by acts of Parliament obtained in 1884 and 1887.[14] By 1890, some 16 miles (26 km) of mains had been installed, supplied by a pumping station at Athol Street, on the bank of the Leeds and Liverpool Canal. Although water was originally taken from the canal, cleaner water supplied by Liverpool Corporation was in use by 1890, removing the need for a filtration plant. At this time two pumpsets were in use, and a third was being installed. Pressure was maintained by two accumulators, each with an 18-inch (460 mm) diameter piston with a stroke of 20 feet (6.1 m). The Practical Engineer quoted the pressure as 75 pounds per square inch (5.2 bar),[15] but this is unlikely to be correct by comparison with other systems. A second pumping station at Grafton Street was operational by 1909.[16] The system ceased operation in 1971.[17]

Birmingham obtained its system in 1891, when the Dalton Street hydraulic station opened. In an unusual move, J. W. Gray, the Water Department engineer for the city, had been laying pressure mains beneath the streets for some years, anticipating the need for such a system. The hydraulic station used Otto 'Silent' type gas engines, and had two accumulators, with an 18-inch (460 mm) diameter piston, a stroke of 20 feet (6.1 m) and each loaded with a 93-tonne weight. The gas engines were started by a small hydraulic engine, which used the hydraulic energy stored in the accumulators, and all equipment was supplied by Ellington's company. Very few documents describing the details of the system are known to exist.[18]

The final two public systems in Britain were in Manchester, commissioned in 1894, and Glasgow, commissioned the following year. Both were equipped by Ellington's company, and used the higher pressure of 1,120 psi (77 bar). This was maintained by six sets of triple-expansion steam engines, rated at 200 hp (150 kW) each. Two accumulators with pistons of 18-inch (460 mm) diameter, a stroke of 23 feet (7.0 m), and loaded with 127 tonnes were installed. In Manchester, the hydraulic station was built on the east side of Gloucester Street,[19] by Manchester Oxford Road railway station. It was later supplemented by stations at Water Street and Pott Street, the latter now under the car parks of the Central Retail Park.[20] At its peak in the 1930s, the system consisted on 35 miles (56 km) of pipes, which were connected to 2,400 machines, most of which were used for baling cotton.[21] The system was shut down in 1972.[20] In Glasgow, the pumping station was at the junction of High Street and Rottenrow. By 1899, it was supplying power to 348 machines, and another 39 were in the process of being completed.[19] The pipes were 7 inches (180 mm) in diameter, and there were around 30 miles (48 km) of them by 1909, when 202,141 imperial gallons (918.95 m³) of high pressure water were supplied to customers. The system was shut down in 1964.[22]

All of the British systems were designed to provide power for intermittent processes, such as the operation of dock gates or cranes. The system installed at Antwerp was somewhat different, in that its primary purpose was the production of electricity for lighting. It was commissioned in 1894, and used pumping engines producing a total of 1,000 hp (750 kW) to supply water at 750 psi (52 bar). Ellington, writing in 1895, stated that he found it difficult to see that this was an economical use of hydraulic power, although tests conducted at his works at Chester in October 1894 showed that efficiencies of 59 per cent could be achieved using a Pelton wheel directly coupled to a dynamo.[23]

Two major systems were built in Australia. The first was in Melbourne, where the Melbourne Hydraulic Power Company began operating in July 1889.[24] The company was authorised by an Act of the Victorian Parliament passed in December 1887, and construction of the system began, with Coates & Co. acting as consulting engineers, and George Swinburne working as engineering manager. The steam pumping plant was supplied by Abbot & Co. from England. Expansion was rapid, with around 70 machines, mainly hydraulic lifts, connected to the system by the end of 1889, and a third steam engine had to be installed in mid-1890, which more than doubled the capacity of the system. A fourth pumping engine was added in 1891, by which time there were 100 customers connected to the mains. The mains were a mixture of 4-inch (100 mm) and 6-inch (150 mm) pipes. The water was extracted from the Yarra River until 1893, after which it was drawn from the Public Works Department's supply. There were some 16 miles (26 km) of mains by 1897. A second pumping station was added in 1901, and in 1902, 102 million gallons (454 megalitres) of pressurised water were used by customers.[25]

The system was operated as a commercial enterprise until 1925, after which the business and its assets reverted to the City of Melbourne, as specified by the original act. One of the early improvements made by the City Council was to consolidate the system. The steam pumps were replaced by new electric pumps, located in the Spencer Street power station, which thus supplied both electric power and hydraulic power to the city. The hydraulic system continued to operate under municipal ownership until December 1967.[25]

In January 1891, a system in Sydney came on-line, having been authorised by act of Parliament in 1888. George Swinburne was again the engineer, and the system was supplying power to around 200 machines by 1894, which included 149 lifts and 20 dock cranes.[26] The operating company was the Sydney and Suburbs Hydraulic Power Company,[27] later shortened to the Sydney Hydraulic Power Company. Pressure mains were either of 4-inch (100 mm) or 6-inch (150 mm) diameter, and at its peak, there were around 50 miles (80 km) of mains,[28] covering an area between Pyrmont, Woolloomooloo, and Broadway. In 1919, most of the 2369 lifts in the metropolitan area were hydraulically operated.[26] The pumping station, together with two accumulators, was situated in the Darling Harbour district, and the original steam engines were replaced by three electric motors driving centrifugal pumps in 1952.[29] The scheme remained in private ownership until its demise in 1975, and the pumping station has since been re-used as a tavern.[25]

Ellington's system in Buenos Aires was designed to operate a sewage pumping scheme in the city.[10]

Geneva created a public system in 1879, using a 300 hp (220 kW) steam engine installed at the Pont de la Machine to pump water from Lake Geneva, which provided drinking water and a pressurized water supply for the city. The water power was used by about a hundred small workshops having Schmid-type water engines installed. The power of the engines was between 1 and 4 hp (0.75 and 2.98 kW) and the water was supplied at a pressure of 2 to 3 bars (29 to 44 psi).[30]

Due to increased demand, a new pumping plant was installed, which started operation in 1886. The pumps were driven by Jonval turbines using the water power of the river Rhône. This structure was called Usine des Forces Motrices and was one of the largest structures for generation and distribution of power at the time of construction. By 1897 a total of 18 turbines had been installed, with a combined rating of 3.3MW.

The distribution network used three different pressure levels. The drinking water supply used the lowest pressure, while the intermediate and the high pressure mains served as hydraulic power networks. The intermediate pressure mains operated at 6.5 bars (94 psi) and by 1896 some 51 miles (82 km) of pipework had been installed. It was used for powering 130 Schmid type water engines with a gross power of 230 hp (170 kW). The high pressure network had an operating pressure of 14 bars (200 psi) bar and had a total length of 58 miles (93 km). It was used to power 207 turbines and motors, as well as elevator drives, and had a gross power of 3,000 hp (2,200 kW).[31]

Many turbines were used for driving generators for electric lighting. In 1887 an electricity generation plant was built next to the powerhouse, which generated 110 V DC with a maximum power of 800 hp (600 kW) and an AC network with a maximum power of 600 hp (450 kW).[31] The generators were driven by a water turbine supplied from the hydraulic power network.[32] The hydraulic power network was not in competition with the electric power supply, but was seen as a supplement to it, and continued to supply power to many customer until the economic crisis of the 1930s, when the demand for pressurized water as an energy source declined. The last water engine was decommissioned in 1958.[31]

In order to avoid excessive pressure build-up in the hydraulic power network, a release valve was fitted beside the main hall of the powerhouse. A tall water fountain, the Jet d'Eau, was ejected by the device whenever it was activated. This typically happened at the end of the day when the factories switched off their machines, making it hard to control the pressure in the system, and to adjust the supply of pressurized water to match the actual demand.[33] The tall fountain was visible from a great distance and became a landmark in the city. When an engineering solution was found which made the fountain redundant, there was an outcry, and in 1891 it was moved to its current location in the lake, where it operated solely as a tourist attraction, although the water to create it still came from the hydraulic network.[34]