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. 1:.... ' ." ' : . ,, ,~ The Story Of Electrical Energy, Pt.22 While Sydney Council generated its own power from 1904, the Railways & Balmain power station provided a big share of the load in years to come~ The privately owned Balmain station was particularly innovative & continued to run until 1973. By BRYAN MAHER Sydney Council's electricity supply undertaking got off to an au.spicious start in 1904, but' it soon had a battle on its hands. The first real expansion into suburbia took place in 1910. The councils of Annandale in the west, Mascot to the south and Woollahra and Randwick in the east all agreed to supply electricity to 82 SILICON CHIP streets, homes and businesses. Long distance transmission to Long Bay Gaol prompted the council's first rise in transmission voltage to 1 lkV and this was completed in 1911. So busy was the Council Electricity Department with suburban extensions that the work ofreplacing the remaining city gaslights lagged and was still incomplete in 1913. This prompted calls for a slowing-down of suburban work. In the midst of these delays, the long-established Redfern Municipality Electric Supply undertaking was actively pursuing business. But then came an entirely new challenge. In 1908, a brand new private enterprise, the Balmain Company, was formed, with the full title of "The Electric Light and Power Supply Corporation". This was no small amateur competitor but was a large, professional engineering organisation, a fierce commercial adversary. Newtown Council rejected Sydney City Council's overtures and opted to buy electricity from Balmain. In quick succession, Leichhardt, Ashfield and Petersham municipalities gave the Left: a classic photo of Ultimo power station taken in 1915. Six turboalternators are pictured here but the original 1.9MW Parsons turbine is out of the picture. Balmain Company exclusive rights to electrify their suburbs. At the same time, the North Shore councils sought to set up their own power stations. Sydney Council's dream of a huge electricity system was in grave danger of being boxed in by competitors! Fast expansion or extinction seemed the only choices. By 1913 the Redfern Electricity enterprise and the remaining city generating company sold out to the City Council. But the Balmain Company was to remain in the picture for years to come. Tungsten filament lamps The original incandescent lamps of Swan and Edison used carbon fibre filaments operating at bright red heat. These were very wasteful, giving mostly heat and little light. The advent of tungsten wire filaments iii 1910 allowed a much higher operating temper::iture, giving more light output per watt. 8ne candlepower per watt of electricity was achieved. This was 13 times more efficient than the old carbon filament lamps. Despite the reduction in electricity consumption per lamp, the load on the council power station continued to increase. By 1914, Pyrmont's output had increased fifteenfold to over 22MW and 10,000 customers. World War I The war years created grave problems for the council's electricity undertaking. In June 1914, a new German-made turboalternator of SMW capacity failed after just three months service. The A.E.G. turbine suffered damage to one blade wheel, requiring replacement parts from Germany but war broke out before they could be shipped. Therefore a replacement turbine was ordered from the British Westinghouse Company and delivery promised within a year. In the meantime the spare blades for the German machine turned up in Sydney Harbour aboard a Swedish ship, Sweden being neutral in the conflict. The Westinghouse order was This was the scene at Ultimo in 1950. A turbine attendant reads the recording instrument panel and logs the steam pressure, condenser vacuum, cooling water temperature & bearing oil temperature & pressure. Turbine attendants worked 8-hour shifts and did not leave their machines during this time. promptly cancelled by agreement. But the new German turbine blades ran for only 10 days and again failed, the rotor blades hitting the stator blades when on load. Desperate to keep the system going, the council engineers took an unusual step. They simply removed the offending blade wheel and let the turbine run with one less set of blades. Though 15% less efficient, it worked. No new generators were installed at Pyrmont until 1921. Railways to the rescue So critical was the power shortage that in 1916 the City Council asked the Railway Commissioner to supply electricity from the Ultimo power station. A 2-year contract was eventually signed for the supply ofup to 4MW of power. Initially, a 6.6kV 25Hz cable was run from the tramway substation in Jamison Street to the City Council's substation almost next door at Lang Park. To make use of this railway power, the City Council purchased transformers and two rotary converters from the USA. These changed the railway's 3-p hase 25Hz AC supply to 480/240V DC for use in city shops and apartments. By April 1919 increasing quantities of 25Hz AC power fro m the railways power stations was supplied to a new City Council substation in Castlereagh Street. The city and suburbs were becoming increasingly dependent on electricity generated at the Ultimo railway power station. Indeed, the then minister for local governm ent preferred th e railway department to supply bulk electricity to outlying suburban councils, who in return would reticul ate power to homes and industries. The reasoning was logical - tramway current load occurred mostly in the morning and evening peak hours. During the day an d at night, the railway power station at Ultimo was only lightly loaded, just when domestic and industrial load was at its peak. Sharing power seemed sensible. Steam turbines introduced Fortunately, when one technology reaches its limit, it sometimes coincides with the practical realisati on of the next. This situation occurred in 1904, with steam reciprocating engines reaching their zenith and steam turbines app earing on the scene. Because of their much higher speed, steam turbines coul d produce much more power at greater efficiency than their reciprocating counterpart. Also JANUARY 1993 83 were purchased, designed to run at 50% overload during peak hours. Running at 750 RPM, they were directcoupled to 4-pole 25Hz alternators. Both were running by 1909, though one machine had to survive a shipwreck on the way out from England. Continued demand for both tramway and city power led to a further 5MW turboalternator being installed in October 1911. This WillanRobinson turbine was called a "disc and drum" type, being a combined impulse and reaction machine. The 4-pole alternator was manufactured by Dick Kerr and Co. The installation of these three turboalternator sets more than trebled the output of the station, from 7MW in 1903 to over 23MW by 1911, making Ultimo the most powerful electricity generating station in the southern hemisphere. These turboalternators at Ultimo power station were made by Standard Waygood Ltd & were commissioned in 1923. Each machine produced 2.5MW 3-phase power at 50Hz for signals, lighting and bulk supply. Taken in 1905, this photo shows the first Parsons turbine installed in Australia, at the Ultimo power station. It was a great deal smaller but much more powerful than the huge reciprocating steam engines which preceded it. because of the higher revolutions, the alternator produced more megawatts for a given size machine. The Parsons works at Newcasth: on Tyne, England, produced the first steam turbine used for electricity generation in the southern hemisphere. This 3000hp (2.24MW) turboalternator set was installed in Ultimo power station in 1904 and was in service by 9th January, 1905. This unit ran at 84 SILICON CHIP 1500 RPM to drive a 2-pole 25Hz alternator, producing 1.875MW of electricity at 6.6kV. It became the precursor of all future designs in power stations. Never again would engineers think in terms of reciprocating engines. The continuing rapid expansion of Sydney's tramway system led to more Parsons turboalternator sets being installed at Ultimo. Two 5MW machines First Sydney Harbour Tunnel The idea of tunnels under Sydney Harbour is not new and you may be surprised to learn that the recently opened traffic tunnel is not the first tunnel under the harbour. So fast did the North Shore tramway system expand between 1902 and the following decade, that difficulties were soon encountered in keeping enough 6.6kV submarine cables in service. The cables originally laid on the floor of the harbour were of 3-core construction, each core having 3 7 strands of 16SWG copper. The lead and jute sheathing was not entirely successful in preventing the ingress of sea water and a few cables were also destroyed by ship's anchors. Therefore, the Railways Department dug a cable tunnel under the harbour, from Longnose Point to Greenwich. The construction of the tunnel was commenced from a point near Louisa Road in Birchgrove, close to Snail's Bay. Simultaneously, a complementary dig was begun on the north side of the harbour at Greenwich near Manns Park. The two digging teams met in the middle below the harbour. Leaky tunnel An expensive construction, this tunnel was large enough for a few men to walk abreast and was lined throughout its length. The walls were fitted with racks in which rested many 3-phase 6.6kV cables. By this means, AC high tension supply was provided for all tramway substations on the north shore. The under harbour passage was electrically lit but electricians who worked down in the depths found it a foreboding place. The sound of boats' propellers in the water above could be clearly heard as could the shuddering thud of a ship's anchor being dropped. Many more 6.6kV cables were laid in this tunnel between 1924 and 1925 to supply the new 1500V DC substations at St Leonards and Gordon for the electrification of the north shore railway. However, water seepage in the tunnel was always a problem and so it needed to be continuously pumped to prevent flooding. Once the Harbour Bridge was opened, the underwater cable crossing· was no longer needed. Eventually, the Railways Department abandoned the tunnel to the invading seawater. 50Hz generation at Ultimo The 25Hz current used by the tramway rotary converters and induction motors was unsuitable for lighting, due to the obvious low frequency flicker. By 1915, the Sydney tramway system was so complex that electric lamp signals were necessary. In that year, a Bellis-Norcom 75kW turboalternator was installed at Ultimo. This generated a 2.2kV 50Hz 3-phase supply, coming on line on 15th July 1916. At vital points in the city and inner suburbs, small transformers reduced this to 120VAC single phase for lighting signals and waiting sheds. Further 50Hz generators were quickly added, one of120kW and two of ZZ0kW capacity. So fast did the system grow that by 1921 those four machines were scrapped, to be replaced by four turboalternators each of 2.5MW 50Hz rating, including two units made in Sydney by Standard Waygood Ltd. Later, between 1925 and 1928, White Bay power station had installed four much larger 50Hz 1 lkV generators, taking over the bulk supply role to Sydney City Council, municipal councils and outlying towns. Thus, high frequency generation at Ultimo was no longer needed and all four 50Hz machines were removed. White Bay power station had been opened by the Railways Department in 1913, initially as a 25Hz supply r. Ultimo power station included an AC/DC substation with five lMW rotary converters. This converted the 25Hz AC supply to 600V DC for trams in the Ultimo area. source. The Standard Waygood works also turned out larger steam turbines and alternators for that plant. The No.4 and No.5 turboalternators for White Bay, both 18.75MWunits, were under construction during 1925/27. These machines were designed by English Electric through their Australian counterpart, Associated General Electric Industries. The heavy casting and machining was shared between Standard Waygood Ltd and Cockatoo Island Dockyard. The alternators were also wound in Sydney. Both were 6.6kV 25Hz units, the largest low frequency machines ever installed at White Bay. Independent Balmain The Electric Light and Power Corporation, an independent private company, secured the franchise to supply the borough ofBalmain in 1906. Consequently, two small reciprocating steam engine driven generators were installed on the eastern bank of Iron Cove. Operation commenced in 1908, beginning one of the longest-lived private generating concerns in Australia. The service area was soon extended to include Newtown, Petersham, Ashfield and Leichhardt and so the generating system was quickly enlarged to become the Balmain A power station. By 1923, Balmain A was a well engineered 10MW system of turboalternators and boiler equipment. Situated immediately north of the Iron Cove bridge on Victoria Road, between Terry Street and the water, the station buildings soon became a well-known landmark. Later Balmain supplied power as far afield as the Parramatta, Granville and Dundas areas, taking over from an earlier generating station at Parramatta. Risky shipping Because Balmain's service area included many industrial and shipping facilities, continuity of supply during World War 2 was vital. Coal and coke were burned, originally supplied by ship from the Newcastle coal fields. Throughout the war years of 1942-45, little colliers such as the William Macarther and Hexham Bank dodged attacks by Japanese submarines. The technique was for the coal ships to ply between Newcastle and Sydney so close inshore that enemy submarines were not game to follow. The smallest of these colliers had such low freeboard that they were almost impossible to spot. The view through an enemy periscope was confused by the background hills of the shoreline, preventing a clear silhouette for torpedo aiming at the slow moving col~ liers. By 1942, Balmain was running turbines rated at 18.75MW, 12MW and 9MW. All of these turbines were driven by steam at 225psi (1550kPa) and 3 70°C. The total installed turboalternator capacity was 39. 75MW but boiler capacity totalled only 27MW. JANUARY 1993 85 L " 1J1! I ::i 2 ·9 Balmain power station was Australia's largest privately owned electricity generating station. It began operations in 1906 in the building at extreme left & progressively expanded to lOOMW capacity. It ceased operation in 1973. tor. Instead, the secondhand unit was transferred to one of the railway's smaller power stations to extend its service life. The inevitable result was that Newcastle used mostly secondhand generators, rotary converters and so on. From 1928 onwards, Ultimo power station only had 25Hz alternators. To provide a standby systeip, a frequency changer was installed at Ultimo in 1937. This 2MW unit consisted of a 6.6kV 25Hz synchronous motor directly coupled to an 1 lkV 50Hz alternator. A belt-driven DC generator supplied the rotor fields of both units. This frequency changer was also secondhand. It had previously served to link the 25Hz and 50Hz systems at Zarra Street power station from 1922 to 1936, until replaced there by a much larger 7.5MW machine. The ultimate Ultimo Clearly more boilers were needed but the company took an approach new to Australia for that time. In a bold step, Balmain installed the highest pressure boiler then seen in Australia, generating steam at 1250 psi (8600kPa) and 490°C. The huge boiler towered 26 metres high, with the 25-tonne drum of forged chrome molybdenum steel mounted 16 metres above the firing floor. The first new 9.375MW turboalternator went into service in 1946, the first "back pressure" machine ever installed in Australia. This machine received steam at 1250psi from the high-pressure boiler and exhausted spent steam at 225psi and a temperature of 370°C. The exhaust steam, the so-called back pressure, was used to drive one or two of the old turbine sets. High efficiency The efficiency of any steam engine depends on the difference in temperature between inlet and exhaust. In the multiple turbine scheme, the inlet to outlet temperature difference is measured right across the high and low pressure machines. Thus, the efficiency of both machines is quite l\igh. Taken together, the 9.375MW high pressure and 18. 750MW low pressure units generated a total of 25.5MW. The condensate water from the low pressure machine condenser was then pumped back into the high pressure boiler to be converted to steam. 86 SILICON CHIP The purpose of the Balmain scheme was twofold: to increase plant capacity and to improve efficiency by enabling old steam turbines to operate within a higher temperature steam cycle. The combined high and low temperature turbines achieved a 50% increase in power output using only 8 % more fuel. Three more 25MW high pressure turboalternator sets and more boilers were later installed at Balmain. The total capacity in 1956 was just over lO0MW and it continued supplying electricity until 1973. Railway alternator swaps Meanwhile, back at the railway's power stations, further modernisation was in progress. Of the four 50Hz generators running at Ultimo since 1921/23, the two Willan-RobinsonDick Kerr units were scrapped in 1928 but the two Australian-made alternators were reinstalled elsewhere. No.1 went to Zarra Street power station in Newcastle in November 1925, where it helped supply that city until 1930. After that, the turbine was removed and reinstalled at Lithgow power station. The No.2 machine became the inaugural generator at the new Lithgow power station which was opened in 1928. These are examples of the musical chairs played by the Railways Department. Their philosophy was not to scrap an old machine when it was to be replaced by a new, larger genera- By 1950, Ultimo had reached its greatest output of 83MW, generated by just four turboalternators. They occupied the large turbine hall which had originally been built to house six huge low-speed vertical reciprocating steam engines and alternators. These would have generated a total of only 9MW. Ultimo was closed by the newly formed Electricity Commission in 1963 at the same time as trams were phased out, leaving White Bay to carry the railways and the bulk supply load. The 65-year history of Ultimo was an accurate reflection of the development of electric power generation. At various stages, Ultimo included nearly every type and class of electricity generation equipment. And on many occasions, it lead the way in size, capacity and technology. Thus, it is fitting for this station to now be the Powerhouse Museum. Sadly, little of the equipment remains today. Acknowledgements Grateful thanks to the SRA Archives and the Trustees of the Sydney Museum of Applied Arts and Sciences for the photographs used in this article. Acknowledgements also to Don Godden et al in "Ultimo Power House; Report on its History and Technology"; also to Victor Poljanski, Arthur Perry, W. H. Myers, G. F. Anderson, P. Smythe, P. Tweedie, J. Brearley, Pacific Power and the Public Works Department of NSW. SC