(Sharecast News) - Power plant operator OPG Power Ventures witnessed a 4.5% production increase in the first nine months of its trading year, predominately driven by an improved performance from its 414-megawatt plant in Chennai.OPG's production hit 2.15bn in the nine months ended 31 December, as total generation at its Chennai plant hit 1.97bn units - 8.4% higher year-on-year due to higher plant availability and increased demand by industrial customers.The AIM-listed group also benefited from higher tariffs, lower coal prices and a continued strong operating performance from Chennai's first, second and third units.However, OPG did note that unit four had been shut down in early December to undertake turbine repairs caused by the malfunctioning of a high-pressure by-pass valve.Average tariffs realised during the first nine months of the year were Rs 5.33 (£0.056) - a slight improvement on the Rs4.96 (£0.052) seen a year earlier.Looking forward, OPG said it was confident that its Chennai plant would shortly return to normal operations and provide the group with a strong performance and EBITDA and profits within market expectations.Executive chairman Arvind Gupta said: "We are pleased to report another strong operational performance by Chennai plant for the first nine months of FY19 and we expect to meet market profit expectations for our full FY19 results."As of 0940 GMT, OPG shares had dipped 0.73% to 20.50p.