It also accused Chief Minister Arvind Kejriwal of not being "strict" with power distribution companies (discoms) and the Delhi Power Minister over the issue.
"Delhi is facing power cuts due to under-purchasing of power and not due to technical faults," BJP Delhi chief Satish Upadhyay said, adding, "BJP will take to streets if the situation does not improve by Sunday."
"Chief Minister Kejriwal should stop the drama of his government's strictness on private partners in discoms. He should use his stick on government officials on Discom Boards and his Power Minister who have all connived with private companies that are short-purchasing power and resorting to power cuts," Upadhyay alleged.
Several areas in West and East Delhi too faced long power outages as the demand for electricity peaked amid sweltering heat.
Officials of Power department of Delhi government said that the discoms have not been investing in improving their infrastructure due to which power cuts are taking place across the city when the load on the network goes up due to higher consumption of electricity.