Tata Power has posted a consolidated net loss of Rs 75 crore for the December quarter, which truncated from Rs 329 crore in the same quarter last year. This is because in the year-ago quarter, the company had taken an impairment charge of Rs 600 crore on its books on account of the Mundra ultra mega power project (UMPP). The company also made exceptional expenditure at its coal mines in Indonesia, which went up by Rs 152 crore. The total other expenses swelled 29 per cent. "Exceptional expenditures were made towards settlement of mining rates, mine rehabilitation costs, forex losses and tax demands in Arutmin coal mines," the company said in a release. In the quarter under review, Tata Power's revenues decreased by four per cent to Rs 8,700 crore compared to Rs 9,039 crore in the year-ago quarter.