Abstract:
In 2010 we conducted a review of the worldwide experiences with injection in geothermal fields based on information from 91 electric-power producing geothermal projects. In the present review we have extended the database to include detailed information about these fields: such as their installed capacity, reservoir information, production and injection conditions, their reinjection strategies and response of different type of geothermal reservoirs to these strategies. The reports and articles available in the open literature were the main source of this review report. Additional information is also presented in the database in order to provide details about each field. This information is summarized in tables and includes data relevant to the steamfield (drilled area, number of production and injection wells, type of reservoir, reservoir temperature and average enthalpy, reservoir depth), to the power plant (type of plant, installed capacity, annual electricity production, number of units, total and steam production rates) and to the type of reinjection (injection strategy and rate). Experience from these ninety-one electric-power producing geothermal fields shows that: a reinjection plan should be planned at the very earliest stages of field development and is likely to change with time depending on the response of the field to various strategies. An optimum reinjection design should balance the requirements to sustain the reservoir pressure and to prevent early breakthrough of cold reinjected water. Also the effects of reinjection on the natural hot recharge, and therefore on energy recovery from the system is an important matter to consider.