Mumbai, Aug. 7 :    Mumbai, Aug. 7:  Tata Power Company Limited received a jolt today when Crisil Ltd downgraded three of its debt programmes citing the private sector energy major's increasing exposure to the Tata group's telecom ventures which have a long gestation period. 'The Tata Power Company's debenture ratings have been lowered because of the company's increasing exposure to the Tata group's telecom ventures, particularly Tata Teleservices Limited, where returns are only expected in the long term,' the Crisil statement said. The Crisil downgrade means that the company will have to fork out almost 25-30 basis points more for any new bond issue, from the current 7.9 per cent for an AAA debt paper to 8.1 to 8.2 per cent. As of now, Tata Power's exposure to the telecom sector, through Tata Teleservices and Panatone Finvest, is Rs 2,500 crore, Crisil revealed. These investments, which have now resulted in a considerable increase in Tata Power's net debt levels, will impact its credit protection measures because of lower accruals and due to the drying up of ample liquidity that the company enjoyed in the past. Tata Power is committed to funding an additional Rs 500 crore of Tata Teleservices' capital expenditure plans this fiscal. The rating change also reflects the company's diversification plans in the power sector, which would expose it to significantly higher credit risks, either in its Mumbai licensee area or in its captive power business. Indicating that its main concerns revolve around the company's foray into the telecom arena, Crisil said: 'Outside the power business, the company has been ramping up its exposure to group companies. Tata Power increased its fund based exposure to the Tata group by Rs 700 crore in 2001-02 besides giving guarantees of Rs 1,000 crore to Panatone Finvest and Tata Teleservices Limited'. The revised ratings, however, find support from the stable cash flows of the license business where the regulatory regime allows Tata Power to earn clear profits on the assets invested. The company has a favourable thermal-hydel generation mix, high plant availability factors and low transmission and distribution losses, which favourably impact the company's credit profile.