A full-fledged Department of Power under Government of West Bengal came into being on 19th September, 1972. Until then, matters pertaining to power were being looked after by the Electricity Development Directorate under the Department of Commerce Industries.
Foundation of Power sector was laid on 27th May 1927 with the commissioning of first Micro Hydel project at Ranikhola near Gangtok with the installed capacity of 50 KW. During this era, activities under power sector in Sikkim were not at all significant. Till the year 1954, operation and maintenance of power supply system were managed with the help of a foreman and an electrician, under the supervision of Sikkim Public Works Department. In the year 1957, keeping in view of growing demand for electricity and as a standby measure, a Diesel power house was established and commissioned at Gangtok with a capacity of 257 KW. Following this development one more 150 KW SKODA Diesel generating set was added in this Diesel Power House. The year 1974 witnessed an important historical event in Sikkim. Following a Political upheaval Sikkim joined the mainstream of the Indian Union on May 16th 1975 as the 22nd state of India. Ever since Sikkim became a part of India there has been all round development in the state. Since then the sector has achieved the tremendous mileage in terms of installed capacity coupled with the Transmission Distribution networks virtually connecting the every household in
Sikkim. Sikkim with its picturesque landscape and amazing terrain has some of swiftest rivulets system has a huge power potential.
The commissioning of the two sets of hydro electric generators having capacities of 100 KW and 56 KW at Leimakhong micro hydel station in 1930 by the then Manipur State Hydro Electric Board marked the beginning of the use of electricity in Manipur. The royal palace and the main area of Imphal town enjoyed electricity generated from this captive hydel station. During the second world war, two more diesel generating sets of 62 KW and 46 KW capacities were installed at the old Imphal Power House by the armed forces for electrification of Imphal and its suburbs. The capacity remained the same without further capacity addition till the end of the first five year plan (1951-56) of the post independence period.
Energy and Petrochemicals Department is one of the administrative department of sachivalaya. The subjects assigned to the energy and petrochemicals department in rules of business and administrative set-up thereof has been mentioned respective in annexure A and annexure B. Energy and petrochemicals department contains hierarchy of a principal secretary as the head of department, three deputy secretaries, one director to rail movement and five under secretaries. The working of the department is divided in four branches, each headed by section officer i.e.class II Gazatted officer.