Witbank Power Station
The Witbank Power Station was a base load station at a high load factor, principally powered by using coal powder, or “duff” as it was known. With its location in the heart of the coal-fields, it enabled the Commission to provide electrical power very cheaply to its consumers.
TURBULENT BEGINNINGS
In the Annual Report of 1924 it is mentioned that a gratifying feature of the settlement reached, is that the interests of both parties have been satisfied. In the commemorative issue of 1948, the agreement between these two parties is described as cordial. This is an example of the good co-operation that the Commission had with other undertakings. The agreement ensured that consumers would enjoy the benefits of a large and up-to-date power station with a guarantee of one-half share in any saving to the VFP resulting from the erection and operation of the Witbank Power Station. Mines, entering into new contract with the VFP, were guaranteed a 15% discount on standard prices from January 1923, rising to 17.5% on the date the Witbank Power Station came into full operation The first formal meeting of the Electricity Supply Commission (ESCOM) was held on 20 March 1923. According to the minutes of the meeting the transfer of the Colenso power station in Natal from the South African Railways, as well as the establishment of power stations at Durban, Cape Town and Witbank was discussed.
The establishment of the power station at Witbank proved to be difficult and almost lead to open confrontation between ESCOM and the The Victoria Falls and Transvaal Power Co., Ltd. (VFP)). The minutes of the second formal meeting held on 18 May 1923 mentions a “confrontation” between the Commission and the VFP.
The VFP was founded in 1906 and registered in Southern Rhodesia (now Zimbabwe). The idea was that the company would become a centralized provider of electricity. The VFP wanted to provide existing as well as future industries with power that would be generated at the Victoria Waterfall and the Zambezi River. Mine owners insisted that a coal-fired power station also be built on the Reef for use in the event of power failures. The idea of harnessing the hydro-potential of the Zambezi River was soon abandoned for technical and financial reasons. The VFP decided to erect thermal power stations close to the user area, thus making use of the coal-fields in Eastern Transvaal (now Mpumalanga).
In accordance with the Power Act of 1910, the VFP wanted to establish a power station in the Witbank area. This area was ideally suited for such an undertaking: the principal coal-fields in the Eastern Transvaal were in the Witbank area, there is an abundance of water, which is an important factor in the establishment of thermal power stations. Such a power station would be in close proximity to the Witwatersrand gold fields, which would be the main consumers. Further, it was hoped that the establishment of a power station in that area would encourage development in that area.
In May 1923 the VFP applied to the Electricity Control Board for an extension of its license to the Witwatersrand. The Electricity Control Board was created by the Electricity Act of 1922 to control the supply of electricity by ESCOM and private undertakings. The Commission had already started examining the power potentialities in the Witbank are and therefore opposed such an extension. The Prime Minister, General Jan Smuts, realized the seriousness of the situation and asked C H Merz, a world-renowned consulting engineer, to mediate between the two parties. A compromise was reached dated 5 July 1924. According to the agreement, the VFP would construct and operate the power station at cost price for, on behalf of, and in collaboration with the Commission. After a period of twelve moths it would be decided if the Commission would take over the operation and working of the station or allow the VFP to continue to operate it on the Commission’s behalf. The Commission would finance and own the station. All land servatudes and other rights acquired were registered in the Commission’s name.
In the Annual Report of 1925 reasons were given for permitting the VFP to construct the power station on behalf of the Commission. These included the fact that the VFP was in a better situation that the Commission to start work immediately, since the Electricity Control Board had already approved many of the plans and specifications. Given the urgent need for additional power on the Rand, this was the only workable option. Whereas, the VFP already received its licence on 21 July 1924, the Commission was only granted its licence to operate in the Witbank area on 6 April 1925.
THE SITE
View of the station
The Commission was licensed to provide electricity to an area within a radius of 24 km from the generating station; the South African Railways and Harbors’ property within a radius of 160 km from Witbank Railway Station and property outside the 160 km radius that formed part of the mail line between Witbank and the Mozambique border at Komatipoort. With the amendment of the license the area was enlarged to a radius of 25 miles in and around Witbank.
When the Commission made its application for a licence to the Electricity Control Board in 1925, it was not known who the consumers would be. Therefore, the layout of the local distribution system could not be determined and prices for the supply of electricity could not be fixed. After the distribution system came into operation, the Commission was in a position to submit standard prices. An application was accordingly made to the Board on the 21 March 1927 for the amendment to the Witbank Licence. These amendments were granted on 29 June 1927. Further amendments to the licence were made over the years as more consumers emerged
CONTRACTS AWARDED
Almost all steelwork for the coal staithes was imported. As was as an engine room crane, a considerable quantity of boiler house material, including sections for three boilers, headers for superheaters, mud drums, superheater tubes, economiser casings and dam pumps, and piping for the pipe line from the dam to the station.
GENERATION
At first the station consisted of three sets, each with a capacity of 23 500 kV on maximum continuous rating. The aggregate capacity of the main generating plant would be 70 500 kV.
Electricity was generated by six main turbo-generator sets of 20 MW and one at 8 MW, giving a total of 128 MW. each at a frequency of 50 periods per second and a pressure of 6 600 V. The station also contained and auxiliary set of 1 MW capacity The pressure was increased to 132 000 V for transmission to the Witwatersrand, while 22 000 V was used in the Witbank area. The station was equipped with twelve boilers, each with a normal capacity of 30 600 kg of steam per hour. The boiler house and the generating sets were housed in a steel frame building.
The first 20 000 kW set was started up provisionally on 3 May 1926, the second on 15 July and the third on 25 October of the same year. In 1926 the power requirements of the VFP on the Witwatersrand, as well as consumers in the Witbank area, increased to such an extent that a fourth 20 000kW generating set and three additional boilers were constructed, bringing the installed capacity of the generating plant up to 80 000 kW. The Undertaking was placed in commercial operation on 1 July 1927. On completion in 1927, the Witbank Power Station was the largest of the Commission’s stations.
The VFP increased its power requirements on the Witwatersrand. To satisfy this increase and to maintain the full output of 80 000 kW during periods when one of the four 20 000 kW set was out of commission for overhaul or otherwise, it was decided to extend the power station. A fifth 20 000 kW set and one additional boiler were added. This brought the installation up to 100 000 kW and sixteen boilers
A railway siding from Witbank Railway Station and permanent sidings on the site were constructed. Coal staithes were erected to provide storage capacity for coal, to be used when the colliery was not operating
COOLING SYSTEM
Thermal power stations need water to produce steam to drive the prime movers, to condense the turbine-exhaust steam, and cool the bearing and generator coolers. At Rosherville and Simmerpan the water was circulated round an open dam, where it lost its heat to the atmosphere. At Witbank spray-pond cooling was used.
TRANSMISSION
The VFP erected on its own account a 112 km double-circuit 132 kV transmission line from Witbank to its generating station at Brakpan. At Brakpan, it linked up with the Company’s main distribution system along the Reef
A 380/220 V distribution system in the Witbank Municipal area consisted mainly of overhead lines for the distribution of electricity to all residential and other consumers within the township as well as for street lighting purposes, which started in August 1927. In the Witbank district the Commission had a 21.000 V reticulation system, consisting of 13 km of underground cables and 20 km of overhead lines transmitting electricity to sub-stations situated in the Witbank Township and on the respective consumers’ premises. This network was place in commercial operation on 1 January 1928.
Due to the lack of accommodation for the operating staff in the Witbank Township, a large housing programme was started in 1925. In the residential area for Europeans houses were built for the Resident Engineer, the Assistant Resident Engineer as well as a rest house, a boarding house and housekeeper’s quarters, three blocks of eight single quarters and 20 married quarters completed houses. In 1926 two additional married quarters and a block of twelve-roomed single quarters were constructed.
A compound was built for the black workers. In 1930 there were 300 blacks living in the compound. According to the housing records the management preferred that they did not live in the municipal area, but in the compound where they could be under strict control of the compound clerk, the police corporal and an induna, for who married quarters were constructed in 1930. It was required of the police corporal to make periodical checks, day and night, of the police boys on duty to ensure that they were at their posts.
The married quarters for black workers were built according to standards set by the Government. It consisted of a rectangular brick building which was plastered and painted. The building was damp proofed and provision was made for gutters over the doors, storm drains and sewerage. The windows were half-opening. The clothing line and the ablution were not communal and houses were equipped with one shower with hot water. The kitchen had a sink, also with hot water and one fireplace. The municipality provided drinking water. In the case of government housing projects adequate funds were not provided to compile with these standards. Whether this was the case with the ESCOM housing scheme is not known.
STAFF
The staff of the Witbank Power station was not employed by the Commission, but by the VFP on behalf of the Commission. This changed in 1948 when ESCOM took over the VFP undertaking.
Bernard Marchand 1895-1972
Mr Marchand was appointed as Engineer on 1September 1926 at Witbank undertaking of which the construction had only commenced. He retired on 31 December 1965 as Manager of the East Transvaal Undertaking. One of the crowning moments of his career was the construction of the 400kV-power network from the Eastern Transvaal to Beaufort West in the Cape. Even though it was only completed in 1969, Mr Marchand was one of the principal players in the development of this delivery system
3rd edition of Megawatt in 1966 an article titled Die “Chief” kom terug appeared which amused Mr Marchand greatly. He loved woodwork and would collect used poles at the depot. A new staff member who did not know him remarked to one of his colleagues that it is amazing that a person with such a low ranked position could afford a Mercedes Benz.
CONSUMERS
The Commission’s most important consumer was the VFP. The bulk of the output was taken by the VFP for supply to gold mines, industries and towns along the Witwatersrand. In terms of the arrangement made between the Commission and the VFP the Company, subject to certain limitations, was required to take all the electricity that could be generated at the Witbank Power station, after meeting the requirements of the Commission’s consumers in the Witbank district. In June 1931 negotiations were undertaken for the extension of the Commission’s distribution system to outlying portions of the Witbank Municipal Area. In the Annual Report of 1936 it is noted that the residential consumers included people of all classes.
Apart from the local residential consumers, the Witbank Power station also had industrial consumers in the area. In the Annual Report of 1926 it is mentioned that a large industrial consumer had transferred its works to Witbank to obtain the benefits of the cheap power available. During the same year four colliery companies also decided to take supplies of electricity from the Undertaking and negotiations with other prospective consumers in the Witbank District had already started. 1929 connected nine collieries in the Witbank District up to the power station. At the end of 1936 all producing collieries in the Witbank district were consumers of the Commission.
Consumers included the following: The Rand Carbide, Ltd. (Supply commenced December 1926); Witbank Colliery, Ltd. (May 1927); S.A. Coal Estates (Witbank), Ltd. (Navigation Colliery) (July 1927); Middelburg Steam Coal and Coke Company, Ltd. (October 1927) and Coronation Collieries, Ltd (Kromdraai Colliery) (December 1927); Tweefontein United Collieries, Ltd. (Negotiations completed end 1927).
As the demand for power increased, the standard tariff was reduced
An important development was the supply of electricity to the South African Railways and harbours Administration for the electrification of the railway system along the Witwatersrand and from Germiston to Pretoria in 1935. Twelve sub-stations, equipped with mercury and rectifiers were planned to supply the direct current required for traction purposes. The electrification of the railway started in 1940, but the outbreak of the Second World War seriously hampered this development and it was only in 1946 that the substation at Elandsfontein started commercial operation.
AGRICULTURAL CONSUMERS
The Witbank Power Station also provided electricity to farming schemes, the first area being in the Elephants River area in the Groblersdal district. After the Second World War electricity provision to agriculture increased substantially. Areas provided by the Witbank Power Station included the Elands River scheme north west of Marble Hall and farms in the Ermelo, Nelspruit, Bronkhorstspruit, Bethal, Leslie, Balmoral, Carolina, Kendal, Hendrina, Koornfontein and Morgenson districts. Electricity was mainly used to power irrigation schemes, but the Forestry nursery at Belfast, a fruit-packing firm at Kiepersol. The Kruger National park and Loskop Dam holiday resort also made use of power from the Witbank Power Station. In 1964 alone 127 farms and 59 other rural users were added to the Eastern Transvaal Undertaking.
DECOMMISSIONING
With the construction of the Wilge, Komati, Camden, Hendrina, Arnot, Kriel and Grootvlei power stations the Witbank power station was used less. The last time it is mentioned in an annual report is in 1963 and in 1970 all operations ceased. The building at Witbank was still used as the headquarters of the Eastern Transvaal Operation.
Feedheating in introduced at Witbank Power Station, where each of the 20-MW sets has a low-pressure feedheater operating on steam bled from the turbine and high-pressure feedheating from the feedpump exhausts. Chairman Dr HJ van der Bijl (1923-1948)
1931
The output decreased by 15,295,245 units, which represented 2,5%. This reduction was due to loading conditions, which affect the machine load factors being less favourable and the fact that sufficient quantities of “duff” coal had not been available, necessitating the purchase and crushing of large coal, with affected coal grading.
1934
4 70/80 000 pound (steam per hour) boilers installed
1935
No extensions of a major character were undertaken, but the transmission and distribution systems were extended. Grit extractors were installed on two of the original boilers. The output of the Undertaking increased by approximately 80 million units over the previous year.
Arrangements are being made to supply the South African Railways and Harbours Administration for the electrification of the railway system along the Witwatersrand and between Germiston and Pretoria. The Witbank Power Station will be used as the main source of power.
1937
An extensive overhaul programme was undertaken. Some of the alternator stations had to be replaced and for sometime the turbo-alternators were out of service.
1940
Electrification of the Reef railway system started 1940. Delayed because of difficulties resulting from the war.
1945
Substation at Elandsfontein (Reef Railway electrification) was completed and commenced operation in April 1946.
This period was characterised by the rapid expansion of operations not only in the Witbank district, but also the Eastern Transvaal. Between 1948 and 1949 alone the number of consumers grew from 1388 to 1551. The consumers were mostly collieries, but included towns such as Bethal, Bronkhorstspruit, Ermelo, Carolina and Breyten. Due to the increase in demand new facilities (feeders, distribution systems, generators, dams, and offices) had to be constructed. Power failures were also experienced during the winter of 1951.
It was also in this period that the most accidents occurred; though the Witbank plant, on the whole, had one of the best safety records of the Commission. In 1952 a 21 kV circuit breaker was destroyed at Rand Carbide. The roof of the plant collapsed, but no serious power failure was experienced. At the Witbank Municipal sub-central a similar circuit breaker was destroyed in an explosion and the town of Witbank was without power for 8 hours.
1948
It is announced that the Commission will buy the electricity undertaking from the VFP, effective from 1 July 1948. The transaction is financed by a public loan of R30 million. The delivery area serviced through this agreement stretches from Witbank in the Transvaal to Winburg in the Free State and comprises of on of the biggest existing grit systems. The assets taken over included the power stations at Rosherville, Simmerpan, Vereeniging and Brakpan; compressed-air installations; almost 60 km of air pipe line; approximately 2 094 km of transmission lined; 1 138 km of pilot and telephone lines; 12 large and six small distribution stations; equipment in 304 consumer substations; 918 transformers. Chairman: Mr AM Jacobs (1948-1952) Dr JT Hattingh (1952-1962)
1954
After the Second World War the mining activities increased due to the demand for uranium. To provide adequate power for this, the Wilge Power Station as constructed near Kendal, in the Transvaal and commissioned in July 1954.
Due to the expansion of the undertakings in the Eastern Transvaal, the name was changed in 1954 to the Eastern Transvaal Undertaking. At that stage the Witbank Power Station was still the biggest producer of electricity, but a yearly decrease in production can be seen.
Only a year after the Komati Power Station started, its power production already exceeded that of Witbank by 4 million units.
The Commission requested an enlargement of its licensed delivery area to include areas around Nelspruit, Witrivier and Barberton as well as an extensive area around Phalaborwa. This was mainly to provide electricity to mines in these areas. Chairman: Dr RL Strazacker
1966
While Komati was still under construction; work was started at Camden Power Station. The first set at Camden was commissioned in December 1966
1969
Before Camden had benn completed, work started Grootvlei
1970
The first set of Hendrina power station is commissioned and the last set in 1978
The Witbank Power Station ceases operation
1971
The first set at Arnot power station is commissioned in 1975
Kriel would be one of the largest stations in the Southern Hemisphere.