a geothermal turbine intallation in which high - pressure steam is separated from geothermal steam , which is a mixture of steam and water , with the high pressure steam connected to a high pressure turbine . low pressure steam produced by flashing the hot water component of the geothermal steam is introduced to a low pressure turbine which is constructed and operates independently of the high pressure turbine . the discharge steam from the high pressure turbine is introduced to a steam condenser operating at a low vacuum while discharge steam from the low pressure turbine is introduced into a steam condenser operating at a high vacuum . the cooling water system of the high and low pressure condensers are connected in series with one another . a maximum power increase is obtained if the flow rates of the high and low pressure steams at the extraction ports of the high and low pressure turbines are made substantially equal to one another .