Reinjection Strategy

Abstract

Because of the complexity of underground conditions within a geothermal reservoir, reinjection is difficult to explain scientifically. Its ultimate purpose is usually for large-scale employment in a field developed and generating electrical energy; therefore, small-scale ad hoc experiments are remote from the final conditions envisaged. The reservoir up-flow of hot water from large discharges of numerous production wells cannot be duplicated except in existing fields such as Wairakei, Hence the argument presented here is that it is only at Wairakei that progressive tests are valid. But parallel tests on the undeveloped Broadlands field should be undertaken with reinjection into the reservoir with production and injection wells interchanged. The emphasis is on maximum scientific returns at minimum cost; otherwise, highly expensive investigations may lead to eventual abandonment of a project.