Mumbai, Sep 2 (IANS): A sudden power crisis gripped India's commercial capital Tuesday with several areas facing power blackouts and load-shedding as a key power generating station developed problems. Normal power supply was only likely to be restored by late night.

The erratic supply was on account of tripping of Tata Power's 500 MW Trombay Power Station Unit No.5 at around 9.45 a.m. on account of a technical hurdle, a Tata Power Company (TPC) official said.

Though restoration work was underway full swing, erratic supply continued till this evening with TPC announcing that full restoration would be possible only by late Tuesday night.

Partial supply was restored through the hydro stations and the TPC activated the initialisation activities of its cold standby Unit No. 6 which runs on oil and was kept on hold with the consent of the procurers.

The TPC said that though power was available in neighbouring areas of Maharashtra, due to overloading of the state transmission network, it could not import power for Mumbai from these distribution companies.

Accordingly, the three main power distributors - TPC, Reliance Energy and BEST - to Mumbai's nearly 17 million population were doing rotational load-shedding in their respective areas with around 200 MW-300 MW power available.

The power blackout and load-shedding - said to be unprecedented for Mumbai in the past over a decade, according to state government officials - hit business, commercial operations besides inconveniencing lakhs of people in residential areas.

The areas affected include business districts of Bandra, Andheri-Saki Naka, Kurla, Parel, Mahalaxmi, and the residential areas of Juhu, Dharavi, Chembur and Grant Road in Mumbai, Santacruz, Ghatkopar, Tilak Nagar and Vikhroli.

Reliance Energy informed through social media that it is in constant touch with Tata Power to ensure restoration of normalcy at the earliest.

The BEST, which supplies power to southern Mumbai, said that after tripping, Tata Power had cut off supply to various feeder units which resulted in load-shedding.

As soon as Tata Power restores supply, the feeders will be switched on to ensure normal supply, BEST officials added.