The protesters also ransacked the station's neighbouring administrative office in Thursday night's incident in rural Sibi, in southern Balochistan province, where temperatures peaked at 45 degrees Celsius (113 degrees Fahrenheit).
«People stormed the electricity supply office and ransacked it last night and a case has been lodged against them,» police official Anayatullah Bungulzai told AFP, adding that the group numbered up to 800 people.
Planned power cuts, also known as loadshedding, happen frequently in Pakistan due to fuel shortages, varying in length in different areas.
In Balochistan, Pakistan's largest province, power outages are prolonged due to both electricity production deficits and unpaid bills by consumers that affect entire neighbourhoods.
Afzal Baloch, spokesperson for the Quetta Electricity Supply Company, told AFP the company suffers «significant» monthly losses due to outstanding payments.
However, protester Noor Ahmad said on Friday they were «compelled» to act over «the excessive loadshedding lasting for hours despite our timely payments of bills».
Sibi is one of the hottest settled areas in Pakistan, where temperatures regularly reach 50C (122F) degrees during heatwaves.
Scientists say such conditions are becoming longer, more frequent and more intense as a result of climate change.
Balochistan is also one of Pakistan's poorest provinces, and battles poor security, rugged terrain, an unreliable water supply and restricted employment opportunities.