Post-war plant

Following the First World War new plant was installed to meet the growing demand for electricity. By 1923 the plant comprised:^[5]

• Coal-fired boilers generating a maximum of 120,000 lb/h (15.12 kg/s) of steam, these supplied steam to:
• Generators
  • 1 × 200 kW reciprocating engine
  • 1 × 500 kW reciprocating engine
  • 3 × 650 kW steam turbines
  • 1 × 1,000 kW steam turbine
  • 1 × 2,000 kW steam turbine
  • 1 × 4,000 kW steam turbine

These provided a total generating capacity of 9,650 kW.

Camber Dock was opened for colliers to deliver coal to the power station.^[4]

Electricity supplies were available to consumers as single phase, 50 Hz AC at 200 and 100 Volts, and 3-phase, 50 Hz AC at 240 and 415 Volts.^[5]

Low pressure plant 1927

New low pressure (LP) generating sets were commissioned in 1927–29.^[6]

• Boilers
  • 1 × Babcock CTM 88,000 lb/h, operating at 250 psi and 650 °F (11.09 kg/s, 17.2 bar and 343 °C)
  • 2 × Babcock & Wilcox CTM each 50,000 lb/h, operating at 250 psi and 650 °F (6.3 kg/s, 17.2 bar and 343 °C), the boilers supplied steam to:
• Turbo-alternators
  • 2 × GEC /Fraser and Chalmers 10 MW sets, operating at inlet steam conditions of 245 psi and 700 °F (16.9 bar and 371 °C).

High pressure plant 1938

High pressure (HP) plant was commissioned in stages: August 1938, September 1941, December 1948, and March 1952.^[6] It comprised:

• Boilers
  • 2 × Clarke Chapman marine type each 123,000 lb/h, (15.5 kg/s)
  • 5 × Bennis quadsum each 165,000 lb/h, (20.8 kg/s)
  • 2 × Mitchell each 180,000 lb/h, (22.7 kg/s)

All the boilers worked at 625 psi and 850 °F, (43.1 bar and 454 °C).

• Turbo-alternators
  • 4 × British Thomson-Houston 30 MW sets, operating at inlet steam conditions of 245 psi and 700 °F (16.9 bar and 371 °C).

Cooling water for the Hick-Hargreaves condensers was abstracted from the tidal harbour. The water flowrate was 6.6 million gallons per hour (30,004 m³/h).^[6]

The turbine hall was 429 feet, by 65 feet by 48 feet tall (131 m × 19.8 m × 14.6 m), and has been claimed to contain one million bricks.^[4][7]

Operating data for 1946

Portsmouth power station operating data, 1946^[10]

Upon nationalisation of the British electricity supply industry in 1948 under the provisions of the Electricity Act 1947 (10-11 Geo. 6 c. 54)^[11] the Portsmouth electricity undertaking was abolished, ownership of Portsmouth power station was vested in the British Electricity Authority, and subsequently the Central Electricity Authority and the Central Electricity Generating Board (CEGB).^[9] At the same time the electricity distribution and sales responsibilities of the Portsmouth electricity undertaking were transferred to the Southern Electricity Board (SEB).

Operating data for 1954–71

Operating data for the period 1954–71 is shown in the table:^{[6][12][13][14][15]}