Difficulties of interconnection, the differences in AC frequencies, and the need for coal conservation by the use of large-scale plant became major issues in World War I when electricity usage nearly doubled. The Electricity (Supply) Act 1919 created a new organisation, the Electricity Commissioners, to replace the role of the Board of Trade. While the initial proposals for national restructuring were thwarted, the Electricity Commissioners managed to develop plans for more efficient and lower-cost generation and to encourage the expansion of service areas to supply small towns and rural areas.
Table 3 lists the statutory supply undertakings in 1925/26. The non-statutory undertakings noted earlier in Table 2 generally continued in existence until acquired by new supply companies or, as in the case of the old established Lynton and Lynmouth companies, were later “legitimized” by Special Order.[18]
In the local authority sector, Bristol had acquired the Keynsham company in 1921 and Torquay Corporation had bought out the Newton Abbot undertaking in 1922 and expanded the generating station there. Three new undertakings had been added to the list: Lyme Regis where the non-statutory company was taken over in 1923, Sidmouth (first supply in 1923) and Tiverton (1924).[19]
Several new companies were added in the 1920s, mostly serving a town and suburbs. These included Bideford and Teignmouth in 1922, Chudleigh and Yeovil in 1923, Seaton in 1924, Budleigh Salterton and Callington in 1925. The North Somerset company, renamed from the Clevedon & District, had also begun a gradual expansion of its service area southwest of Bristol.
The 42 undertakings in 1925/26 operated a variety of systems. DC was the most common, with 27 systems, and had been popular in the early years of electrification. With an economic operating radius of 1-1.5 miles from the generating plant, DC was suitable only for city centres or small towns and villages. The 15 undertakings with AC systems were further subdivided by different frequencies. Nine operated at 50 cycles (Hz) a frequency that had become a national standard after 1903. Bath and Bristol also had parts of the cities working at 100 Hz and 93 Hz respectively. Exeter’s system worked at 60 Hz and the Cornwall Electric Power Co. and related distributors had adopted 25 Hz in 1910. At this time, this was a popular frequency in South Wales, the Birmingham area and the Clyde Valley for traction and industrial power.
Table 3 South West England: Electricity Supply Undertakings 1925/26
The data on generating capacity in Table 3 show that all but seven of the 42 undertakings generated their own electricity. Only nine undertakings had generating capacities of over 1,000 kW. Steam turbines were dominant in all the larger power stations and the units varied in size from one at 7,000 kW at Feeder Road, Bristol to a 150 kW machine in Frome.[20] A few places such as Barnstaple, Dartmouth and Ilfracombe were wholly served by reciprocating steam engines. Other types of generating technology included gas engines (important in Bideford, Bridgwater, Minehead and Tiverton) and diesel engines that were widely employed in small power stations.
Statistics on electricity consumption per head of population reveal major contrasts among electricity undertakings. Only three places, Bristol, Frome and Torquay, exceeded 100.0 kWh per person. Many smaller places such as Ilfracombe and Totnes, which had electric supply for 20 years, languished at 16.0 kWh per capita. Each place had a distinctive market profile reflecting the local economic and social geography. Exeter had a well-balanced profile, consisting of 48.2 percent in the lighting segment, 5.1 percent in public lighting, 21.5 percent in tramways and 25.2 percent in power. Tramways in Bath were operated by a private company with its own power station. Unlike Exeter, Bath had a large engineering works (Stothert & Pitt) which took a significant part of the Corporation’s power supply. Two towns, Exmouth and Frome, had similar populations (around 10,000) but very different market profiles. Exmouth was dominated by lighting at 89.6 percent, while in Frome the power sector amounted to 88.0 percent. Annual per capita sales in Exmouth were only 20.8 kWh while per capita sales in Frome had reached 132.4 kWh.
Electrification and extension of supply areas were given a new impetus following the Weir Report (1925),[21] the Electricity (Supply) Act 1926 and the formation of the Central Electricity Board in 1927. Even before the detailed regional plans for the National Grid were announced, there was a quickening of interest in the formation of new companies and applications for Special Orders. Over the next decade almost all the empty areas of the map were covered by new or extended supply areas. The only unclaimed areas were a small area of Exmoor south of Lynmouth, an area northwest of Bridport, and a curious sliver of territory on the northern edge of Bath.
New local authority suppliers after 1925/26 were Bridport Borough (population 5,917 in 1931) and the Plympton St Mary Rural District Council (population 23,543). Both areas began service in 1929. Plympton St Mary was a fairly rare example of a Rural District Council becoming an electricity supplier. Some existing local authorities were also active in extending their supply area, the most notable being Bristol and Torquay. Bristol acquired the Almondsbury undertaking in 1929, extending into the Thornbury Rural District. Torquay, by the mid-1930s, had the largest area of any local authority supplier in the South West, covering the Newton Abbot, Totnes and Kingsbridge Rural Districts. The small Totnes undertaking was acquired in 1935. In 1948 the Torquay Corporation supply area covered 354 square miles, very much larger than the borough area of 9.7 sq mls.
In the company sector there were ten new formations and three former non-statutory undertakings that had become authorised. Apart from Salcombe Gas & Electric (service begun 1930) which was the last of the small area creations, the new organisations all covered virtually all the territory previously unclaimed. Several earlier undertakings were often incorporated into the new companies. The East Devon company, for example, acquired the Sidmouth UD, Budleigh Salterton and Exmouth company operations. The Exe Valley company incorporated several non-statutory businesses in Bampton, Dulverton and South Moulton, as well as the system built by Crediton UD.
Transmission lines supported by tall steel towers became the most visible effect of state intervention as they appeared In the landscape during the early 1930s. Construction of a national grid was authorised by the Electricity (Supply) Act 1926. Plans were prepared by the Electricity Commissioners and consulting engineers for implementation by the Central Electricity Board.[22] The South West England and South Wales Electricity Scheme was adopted by the CEB in June 1930, tenders were advertised, contracts made, and construction work began.
In the South West a simple 132kv transmission line was built across the region from Hayle to Bristol where there were connections to the Midlands and South Wales and eastwards to Oxford and London. Exeter was also a junction point with a line via Dorchester to Southampton (Figure 3). The national grid was designed to connect “selected” power stations. These were generally the largest and most efficient generating plants which also had some potential for expansion. Six power stations in the South West were on the selected list in 1934:
- Bath Corporation (connected to the grid at Melksham by a 33kv line).
- Bristol Corporation, Portishead (opened in 1929)
- Cornwall Electric Power Co., Hayle
- Exeter Corporation
- Plymouth Corporation
- Torquay Corporation (Newton Abbot)
Two other stations at Bristol (Feeder Road) and Taunton were added later as “special agreement stations”. Remaining power stations were expected to continue until they became too expensive to operate; Barnstaple and Weston-super-Mare lasted until 1958.
All electricity distributors were expected to draw their grid supplies from the nearest power station substation. There were only two special substations in the South West. One at Fraddon, easily reached from Newquay, St Austell and Truro. The other at Bridgewater Main where the CEB also erected lower voltage lines (33kv) to Weston-super-Mare via Burnham, Langport (for North and South Somerset companies), Watchet (for Minehead) and Taunton.
The Grid Scheme plans of 1929/30 made no provision for supply to northwest Devon and this area was still self-sufficient in electricity generation in 1935/35. Whitehall Securities built its own 33kv line to Bideford from Exeter in the late 1930s. The West Devon company was one of the last undertakings in England to have to develop its own generating system. From 1931 the company built a series of diesel and hydroelectric stations to serve its very large area of 817 square miles. West Devon was finally connected to the Grid in July 1942 when the company built its own 33kv line to the Exeter substation from Okehampton.[23]
Table 4 South West England: Electricity Supply Undertakings 1935/36
When trading began on 1 January 1935, the grid had added a new layer to the complex of undertakings which operated the electricity supply system. The Bristol grid control office of the CEB now managed the flows of power on the transmission lines and directed the hour-to-hour operation of the selected power stations. These stations, such as the one in Plymouth, remained in the ownership and management of the Corporation but the daily operation was now directed from Bristol. Portishead, the largest power station, worked continuously to serve the regional base load. Other selected stations generally worked two shifts to cover the daily demand. Planning for the future became increasingly centralised, particularly from London.
Table 4 and Figure 3 show the situation in 1935/36 when 53 undertakings were in operation. Over the previous decade many changes had taken place. One significant shift was the decline in the number of wholly DC systems (from 27 to 9) while the AC systems increased from 7 to 30. The number of combined AC/DC systems also increased. Frequency standardisation at 50 Hz was almost complete by 1936, leaving only the isolated Lynton & Lynmouth Company operating at the old 100 Hz frequency. The cost of the conversion, mostly in Cornwall and Exeter, was one of the expenses of the national grid.
Interconnection between undertakings, which had been minimal in the early 1920s, was now normal practice in most places. The Electricity Commissioners, as part of their mandate for reorganising generation, had encouraged bulk supply agreements between neighbouring undertakings and small stations could be closed. Such agreements would be a benefit for the later grid system, reducing the number of transformer stations. Torquay Corporation made its first agreement, with Paignton, in 1925. Further agreements followed with other companies in Teignmouth (1926-27), Salcombe (1930-31), Dartmouth (1930-31), Totnes (1933-34) and finally Brixham (1935-36).[24] The Teignmouth company made similar agreements with its neighbours in Dawlish (1931-32) and Chudleigh (1934-35). As a result of these arrangements, many smaller systems were linked up with the Newton Abbot power station. By 1935-36 only 13 undertakings generated all their electricity requirements. Five were local authorities–Barnstaple, Bridport, Lyme Regis, Taunton and Tiverton. The eight companies were Bideford, Brixham, Ilfracombe, Launceston, Lynton & Lynmouth, St Austell, West Devon and Weston-super-Mare. Isolation from the grid explains why some undertakings such as Barnstaple and Bideford were wholly independent. For places such as Taunton and Weston-super-Mare, the grid connection was still being built.[25]
Generating technology emphasized economies of scale with larger units. Portishead power station, opened in 1929, had two 20,000 kW and one 50,000 kW generators at this time. Such machines and the larger boilers were much more economical in coal consumption. By 1936 coal consumption at Portishead was 1.09 lb per kWh generated compared with 2.4 lbs at the older Feeder Road station. Such changes in efficiency contributed to reducing the cost of electricity. Diesel power from smaller stations continued to grow and water power reappeared as new stations were built at Mary Tavey and Morwellham.
Rationalisation of generation and interconnections of undertakings contributed to reducing the cost of electricity. Other factors such as the growth of radio broadcasting and lower prices for small appliances helped to boost electricity consumption. By 1937/38 there were 17 places with per capita consumption above 100 kWh, ranging from Bristol at 392.1 kWh to Bridport and Lyme Regis at 100.2 kWh. Places with little industrial demand still tended to lag behind.
The growth of electrification, especially in the lighting segment, may be illustrated by the case of Exeter. Total electricity sales grew from 3.86 million kWh in 1925/26 to 17.40 m kWh a decade later. The lighting segment which included domestic users expanded from1.86 m kWh to 13.30 m kWh over the same period. There was a corresponding increase in the number of consumers. Over the decade per capita consumption in Exeter rose from 59.4 kWh to 219.1 kWh.[26]
While the creation of new areas appeared to be making an even more fragmented map, much of the new development was controlled by holding companies which provided a new form of integration. Figure 4 and Table 5 show the situation in 1937 when three organisations had a dominant position.
Edmundson’s Electricity Corporation had, in the late 1920s, been revived by US capital and began new acquisitions. By 1935 the company was the second largest in Britain. In the southwest, the Cornwall Electric Power Co. acquired all but two of the small distribution companies established in the previous decades in its territory.[27] The Frome and Yeovil undertakings were transferred to Wessex Electricity, a large Edmundson’s operation created in 1927.
Christy Brothers’ subsidiary, the North Somerset company, had expanded southwards and acquired several local undertakings.[28] The company also established the West Devon operation which acquired a large territory and built up a self-contained system based on hydro-electric stations from 1930.
Whitehall Securities Ltd was a new entrant from 1928 acquiring existing undertakings and developing new franchises from its base in Exeter. Outside capital backing was essential for the development of new supply mains across its extensive territory. The various companies operated under the title of West of England Electricity.[29]
Other new corporate entities included the Southern Area Electricity Corporation Ltd (Salcombe & Seaton) and British Power & Light Corporation which held the franchise for South Somerset.
Seven company areas remained outside the larger national groups. St Austell and Bridgwater covered fairly extensive territories, while Brixham, Chudleigh, Lynton & Lynmouth, Falmouth (Electric Supply Corporation) and Weston-super-Mare (British Electric Traction) were only small enclaves.
Although state intervention had begun to rationalise electricity generation, the efforts of the Electricity Commissioners to reduce the very large numbers of distributors were unsuccessful. The McGowan Report published in May 1936 and the subsequent government proposals were strongly opposed by many sections of the electricity supply industry.[30] A recommendation in the McGowan Report, that all undertakings with sales of less than 10 million kWh should be amalgamated, was particularly controversial. In the South West, only seven of the 53 undertakings were above this limit. The seven included Bath, Bristol, Exeter, Plymouth, Torquay, the North Somerset Co. and Cornwall Electric Power Co. The government responded with an Outline of Proposals in April 1937 but the continued opposition and more pressing issues of the time meant that reorganisation of distribution was set aside.[31]
Edmundson’s Electricity Corporation took note of these moves toward amalgamation and reduced the number of small subsidiaries in Cornwall and Wessex company territories. The spatial organisation of 1937 (Figure 4) remained essentially unchanged until nationalisation a decade later.
Table 6 lists the various undertakings that were consolidated between 1914 and 1948. Only three of the 24 were local authorities. Devonport was part of the Plymouth area local government unification. Sidmouth and Crediton UDs both merged with local companies.
Between 1935-46 and 1948 a few small power stations were closed. These included Lyme Regis, Tiverton, Braunton, Witheridge (Exe Valley Co.) Launceston, St Austell, Salcombe and Princetown (West Devon Co.) Taunton power station, closed in 1937, was later recommissioned in 1948 and worked until 1957.[32]
Table 6 South Western England Consolidation of Electricity Supply before 1948
[18] Although non-statutory undertakings were not listed in the Engineering and Financial Statistics, all new stations and extensions of existing stations required the consent of the Electricity Commissioners. The Electricity Special Order for Lynton and Lynmouth was dated 10 December 1928. The ESO had been made by the Electricity Commissioners on 7th September. It was later confirmed by the Minister of Transport and subsequently laid before each House of Parliament for at least 30 days. (Electricity Commissioners Annual Report 1928-29, p.187) and Annual Report 1920-21, pp.29-30. The procedures for Special Orders were described in the Annual Report 1920-21, pp.29-30, fn.18, p.7.
[19] Tiverton had been granted an Electric Lighting Order as early as 1890 but no action had followed. An Electricity Special Order dated 6 March 1924 authorized the borough to establish an electricity system.
[20] The Frome machine dated from 1904 when the new generating station was one of the first to be equipped with turbines. R.A.S Hennessey, The Electric Revolution (Newcastle-upon-Tyne: Oriel Press, 1972) p.87. Bristol’s first turbine set, a 1,000 kW unit, was installed in 1905. Peter G. Lamb, Electricity in Bristol 1863-1948 (1981) p.17.
[21] Ministry of Transport, Report of the Committee appointed to review the National Problem of the Supply of Electrical Energy (London: HMSO, 1927), 39 pp.
[22]Tenth Annual Report of the Electricity Commissioners 1929-1930 (London: HMSO, 1931), p.14.
[23] F.E. Pitt, “Hydro-electric developments in West Devon”, Journal of the Institution of Electrical Engineers Vol. 92(1), 1945, pp. 111-113. The paper also includes a very detailed map of the company’s transmission system.
[24] The dates are taken from the Electricity Commissioners Annual Reports.
[25] The 33 kV line from Bridgwater Main transformer to Taunton station was completed late in 1936. See Gledhill and Lamb, Electricity in Taunton 1889-1948 p.1
[26] The data are derived from the Engineering and Financial Statistics 1935-36.
[27] Eric Edmonds, “Electricity in Cornwall” Pt 2, Histelec article No S23. Edmonds note the major consolidation of all the Edmundson’s subsidiaries after the Cornwall Electric Power Act 1936.
[28] Peter Lamb & Eric Lodge, “Christy Brothers in the South West”, Histelec article No S15.
[29] Selwyn Grant, “West of England Electricity”, Histelec article No S26.
[30] Ministry of Transport, Report of the Committee on Electricity Distribution, May 1936 (London: HMSO, 1936). The report noted that there were no fewer than 635 separate authorised undertakings in Great Britain in 1934, comprising the Central Electricity Board, 3 Joint Electricity Authorities, 5 Joint Boards, 373 Local Authorities and 253 Companies and persons.
[31] Ministry of Transport, Electricity Distribution: Outline of Proposals (London: HMSO, 1937).
[32] Gledhill and Lamb, Electricity in Taunton, pp.21/26. Central Electricity Authority, Annual Report 1957-58, p.24.
