It has been decided to increase the penalty on windmills operating without capacitors to 30 paise per unit, Mr B. Poornalingam, chairman Tamil Nadu Electricity Board (TNEB) announced at Chennai today. The hike from the existing 10 paise on every unit, will come into force on October1, he said at a seminar on 'energy efficiency in India- state of the art' organised jointly by the Madras Chamber Chamber of Commerce and Industry (MCCI) and the Council of Energy Efficiency Companies. Besides, improving the power factor, capacitors helped in stabilising voltage.