| Llanelly power station | |
| Country: | Wales |
| Location: | Llanelli |
| Status: | Decommissioned |
| Construction Began: | 1910 |
| Commissioned: | 1910 |
| Decommissioned: | Late 1960s |
| Owner: | Llanelly and District Electric Lighting and Traction Company Limited (1910–1924) Llanelly and District Electric Supply Company Limited (1924–1947) British Electricity Authority (1948–1955) Central Electricity Authority (1955–1957) Central Electricity Generating Board (1958–1970) |
| Operator: | As owner |
| Th Fuel Primary: | Coal |
| Th Fuel Secondary: | Oil |
| Th Technology: | Steam turbines |
| Ps Chimneys: | 5 |
| Ps Cooling Source: | Seawater |
| Ps Units Operational: | 1 x 12.5 MW, 1 x 7.5 MW, 1 x 5 MW |
| Ps Units Manu Model: | British Thomson-Houston |
| Ps Units Decommissioned: | All |
| Ps Electrical Capacity: | 24 MW |
| Ps Annual Generation: | 83.6 GWh (1946) |
Llanelly power station, also known as North Dock power station, supplied electricity to the town of Llanelly (Llanelli since 1966) and the surrounding area from 1910 to the late 1960s. The power station was owned and operated by a succession of companies, including the Llanelly and District Electric Supply Company Limited, prior to the nationalisation of the British electricity supply industry in 1948. The power station was redeveloped in the 1920s to meet the increased demand for electricity.
In 1891 Llanelly Corporation applied for a provisional order under the Electric Lighting Acts to generate and supply electricity to the town. This was granted by the Board of Trade and was confirmed by Parliament through the Electric Lighting Orders Confirmation (No. 4) Act 1891 (54 & 55 Vict. c. lii).[1] The corporation did not construct an electricity supply system but transferred the provisional order to J. C. Howell Limited, which was established on 20 December 1905.[2] The provisional order was subsequently transferred to the Llanelly and District Electric Lighting and Traction Company Limited when it was established in 1911. This company also supplied current for the Llanelly and District Electric Tramways from June 1911 until the tram system closed in September 1932. In 1924 the Lighting and Traction company changed its name to Llanelly and District Electric Supply Company Limited.[3]
Llanelly power station was constructed at the north east corner of the North Dock (51°41'33"N 04°10'15"W).[4] The location facilitated the supply of coal for the boilers, and cooling water which was drawn from the sea. Further equipment was added to meet the rising demand for electricity; by the late 1920s the station had a generating capacity of 25 MW.[5]
In 1923 the generating plant at the Llanelly power station comprised:
These machines gave a total generating capacity of 6,250 kW comprising 5,750 kW of alternating current (AC) plus 500 kW of direct current (DC).
Electricity supplies to consumers were:
New plant was commissioned and installed at the Llanelly power station from 1923 to 1928. This comprised:[6]
The boilers were manufactured by Babcock & Wilcox and Yarrow and supplied steam to:
The station was supplied with coal via a siding off the nearby dock railway line.
Condenser cooling water was drawn from the sea.
The supply of electric current in the early years of operation of Llanelly power station was as follows:[7]
| 1915 | 3,479 | |
| 1916 | 4,048 | |
| 1917 | 4,359 | |
| 1918 | 5,675 | |
| 1919 | 5,826 | |
| 1920 | 6,761 |
The electricity supply and consumption data for the period 1921–23 was:
| Units | Year | ||||
|---|---|---|---|---|---|
| 1921 | 1922 | 1923 | |||
| Lighting and domestic | MWh | 480 | 773 | 715 | |
| Public lighting | MWh | 175 | 157 | 178 | |
| Traction | MWh | 454 | 459 | 514 | |
| Power | MWh | 5,554 | 7,853 | 11,214 | |
| Bulk supply | MWh | 0 | 0 | 0 | |
| Total use | MWh | 6,663 | 9,243 | 12,620 | |
| Year | 1921 | 1922 | 1923 | ||
|---|---|---|---|---|---|
| Maximum load | kW | 2,655 | 3,529 | 3,780 | |
| Total connections | kW | 8,000 | 9,734 | 10,670 | |
| Load factor | Per cent | 18.5 | 17.8 | 17.7 | |
The Corporation tramways ceased operating in September 1932.
The supply of electric current in the inter-war period was as follows:[8]
| 1921 | 7,080 | |
| 1922 | 12,605 | |
| 1923 | 13,761 | |
| 1926 | 12,330 | |
| 1927 | 18,300 | |
| 1929 | 23,675 | |
| 1930 | 24,546 | |
| 1931 | 24,092 | |
| 1932 | 24,282 | |
| 1933 | 26,143 | |
| 1936 | 37,952 | |
| 1938 | 53,066 |
Llanelly power station operating data for 1946 was:[9]
The British electricity supply industry was nationalised in 1948 under the provisions of the Electricity Act 1947 (10 & 11 Geo. 6 c. 54).[10] The Llanelly and District Electric Supply Company Limited was dissolved, ownership of Llanelly power station was vested in the British Electricity Authority, and subsequently the Central Electricity Authority and the Central Electricity Generating Board (CEGB).[11] At the same time the electricity distribution and sales responsibilities of the Llanelly Electric Supply Company were transferred to the South Wales Electricity Board (SWEB).Between 1964 and 1966 the boilers were converted to oil-firing. Operating data for the period 1954–67 was as follows.[12] [13]
| 1954 | 4548 | 24 | 59,947 | 14.11 | |
| 1955 | 3315 | 24 | 39,188 | 13.83 | |
| 1956 | 1992 | 24 | 22,122 | 13.69 | |
| 1957 | 1564 | 24 | 18,917 | 13.91 | |
| 1958 | 1151 | 24 | 13,507 | 13.75 | |
| 1961 | 5.7 % | 24 | 11,933 | 13.15 | |
| 1962 | 4.5 % | 24 | 9,483 | 13.01 | |
| 1963 | 7.0 % | 24 | 14,722 | 13.64 | |
| 1967 | 5.0 % | 24 | 10,413 | 14.39 |
Following nationalisation Llanelly became an electricity supply district, covering 161.1 square miles (417 km2) with a population of 106,810 in 1958. The number of consumers and electricity sold in the Llanelly supply district was:
| Year | 1956 | 1957 | 1958 | |
| Number of consumers | 31,685 | 32,528 | 33,171 | |
| Electricity sold MWh | 337,312 | 344,323 | 342,339 |
| Type of consumer | No. of consumers | Electricity sold MWh | |
|---|---|---|---|
| Domestic | 28,562 | 30,472 | |
| Farms | 833 | 2,397 | |
| Commercial | 3,344 | 12,614 | |
| Industrial | 420 | 295,439 | |
| Public lighting | 12 | 1,417 | |
| Total | 33,171 | 342,339 |
Llanelly power station was decommissioned in the late 1960s,[14] and was demolished in 1972.