Hardingstone Junction power station

By 1913 the growth in demand for electricity was such that the company sought to build a new generating station at Hardingstone Junction. Work on the new station began in 1916 and operation began in 1919.^[3]  

By 1923 the company operated both power stations. The Bridge Street station generated Direct Current electricity.^[5] The plant at Bridge Street comprised 2 × 220 kW, 1 × 400 kW and 2 × 600 kW reciprocating engines and generators and 1 × 300 kW turbo-alternator, a total of 2,340 kW. These were supplied with up to 57,000 pounds per hour (7.18 kg/s) of steam from coal-fired boilers.^[5]

The Hardingstone Junction/Nunn Mills power station generated alternating current and comprised 1 × 500 kW, 1 × 1,000 kW and 1 × 3,000 kW turbo-alternators supplied with up to 86,200 lb/hr (10.86 kg/s) of steam from coal-fired boilers.^[5]

The total amount of electricity generated in 1923 was 10.947 GWh and there were 13,575 connections to the system. The amount of electricity sold was 8.468 GWh producing a revenue of £94,255. The surplus revenue over expenses was £58,457.^[5]

New plant 1926–1956

From 1926 to 1929, a new low pressure plant was installed at Hardingstone Junction, this was followed by an intermediate pressure plant in 1936-52 and a high pressure plant in 1956.^[6] By 1959 the plant comprised the following.^[6]

Boilers:

• 2 × 45,000 lb/hr (5.67 kg/s) Stirling boilers, 210 psi at 650 °F (14.48 bar at 343 °C)
• 2 × 60,000 lb/hr (7.56 kg/s) Stirling boilers, 210 psi at 700 °F (14.48 bat at 371 °C)
• 4 × 150,000 lb/hr (18.90 kg/s) Stirling boilers, 425 psi at 810 °F (29.31 bar at 432 °C)
• 2 × 175,000 lb/hr (22.05 kg/s) Simon Carves boilers, 425 psi at 825 °F (29.31 bar at 441 °C)
• 2 × 150,000 lb/hr (18.90 kg/s) Bennis boilers, 625 psi at 860 °F (43.1 bar at 460 °C)

Turbo-alternators:

• 1 × 10 MW Metropolitan Vickers
• 1 × 12.5 MW Metropolitan Vickers
• 3 × 30 MW Parsons
• 1 × 30 MW Brush

Cooling water was abstracted from the River Nene, there was also one Mouchel and one Moss concrete cooling towers, each had a capacity of 2 million gallons per hour (2.53 m³/s) with a cooling range of 20 °F (11 °C).^[6]

In 1926 the station was supplying electricity to the railway works at Wolverton, now part of Milton Keynes.^[7]

The company continued to expand its area of supply. For example, in 1927 there was 144 miles of high-tension lines and 108 miles low-tension distribution mains.^[8] These supplied electricity to Bletchley (20 miles from Northampton), Stony Stratford, Towcester and Long Buckby and intermediate villages. By 1936 there were 566 miles of high voltage lines, and 414 miles of low voltage distribution mains.^[9]

At the end of the 1930s the electricity supply arrangements for Northampton were unusual. Outside of London all towns with a population of over 60,000 were supplied by municipally owned electricity undertakings. Northampton, Newcastle and Bournemouth were the only exceptions where company undertakings supplied electricity.^[10]

Nationalisation

The Electricity Act 1947 nationalised the electricity industry and established the British Electricity Authority, which became the Central Electricity Authority (CEA) in 1955.^[11] The BEA took over the electricity generating capability of the NELPC and promoted efficient generation, transmission and distribution and cheaper prices in rural areas. It also standardised the system and electrical fittings and had 11 divisions and 12 area boards. The electricity distribution and sales part of the NELPC became part of the East Midlands Electricity Board (EMEB). The CEA was in turn dissolved by the Electricity Act 1957 and replaced by the Central Electricity Generating Board (CEGB) and the Electricity Council.^[11]

The generating capacity, electricity output and thermal efficiency were as shown in the table.^{[5][6][12][13][14][15]}

The electricity output from Northampton power station, in GWh, is shown in the chart:

Graphs are unavailable due to technical issues. There is more info on Phabricator and on MediaWiki.org.

In 1958 the Northampton electricity district supplied an area of 201 square miles and a population of 144,000. The amount of electricity sold and the number and types of consumers was as follows:^[6]

The power station was closed on 25 October 1976.^[16]