The Tasman Pulp and Paper Company Ltd.'s Mill at Kawerau, New Zealand, has been utilizing geothermal energy for more than 30 years. The mill produces approximately 200,000 tonnes of kraft pulp and 400,000 tonnes of newsprint per annum. Geothermal energy produces 26% of the process steam requirements and 6% of the mill's electrical load. The management of the mill's energy sources is complex and ever changing, which has resulted in unique control strategies being developed over the years to improve efficiencies in the operation of the plant. Complete utilization of the geothermal resource has been the aim of the company and has led to pioneering plant and process developments.