In an effort to increase general efficiency, the plant underwent a fair degree of renovations and improvement works, to be equipped with new machinery and power-generators to increase the overall electrical power output with a brand-new gas turbine and new tall chimneys. However, these efforts were futile as St. James Power Station remained expensive to operate at 3.57 cents for per unit of electrical power produced against 1.4 cents of the same amount yielded at the nearby (also, then-new) Pasir Panjang Power Station, first constructed during the 1950s. The power station was finally decommissioned in 1976 due to its high overall operating costs and the island's continually-growing demand for electricity and was shut down after consuming its last reserves of gas fuel. The old power plant's machinery were removed and the entire building was left vacant.