TPC suggests water recycling for power

The Maharashtra State Electricity Board (MSEB) may be able to ramp up its power generation by an additional 150 mw by next year if a cost effective method (read cheap power) becomes available to it for recycling the water used for its hydro-project.

According to Tata Power Company (TPC) executive director P K Kukde, TPC already utilises this method for additional power generation.

"We had started discussions with both MSEB and Western Region Electricity Board (WREB) in August 2004 on utilising the pump storage capacity (PSC) option for increasing MSEB's power supply. Ultimately, it is an issue of economics," Kukde said.

He added that the whole process would become economically viable only if the electricity grid is able to access cheap power at near Rs 2 per unit rates for pumping the water from the bottom of the reservoir into the main reservoir.

Explaining the cost structure, Kukde said, "Lets say 100 units are required for pumping the water so that 70 more units are produced. So if the cost of per unit is Rs 2, then Rs 200 would be required to produce 70 more units in which case the effective cost of power so generated would be Rs 2.70 per unit. This would become a viable option by next year when the Tarapur facility starts giving MSEB its share of cheap power," Kukde said.

Currently, however, MSEB has to purchase power even at non-peak hours from TPC.

At present even the midnight purchase from TPC hovers around 200 mw to 250 mw. One fallout of this has been that MSEB is unable to ramp down its Koyna facility during non-peak hours using TPC power, that could then be ramped up during peak hours to generate around 400 mw to tide over the power crisis in the state.

Even the water availability for the Koyna hydro project has been severely constrained, making matters worse.