Abstract

The geopressured geothermal aquifers of the South-Central United States represent a potentially enormous store of mechanical, thermal and chemical energy. Nonetheless, it is not yet certain whether that energy can be utilized in ways that are technically sound, economically attractive and environmentally clean. This chapter reviews the principal issues and concerns related to the possible recovery and conversion of energy from the geopressured resource.

Geopressured brines occur in well-defined sandstone formations, or reservoirs, which vary widely in size, temperature and productive capacity. Plants capable of generating electricity from geopressured "fuel" would require certain minimum reservoir properties. To what extent Gulf Coast geopressured aquifers meet these criteria has not yet been determined. Less stringent reservoir requirements would govern the direct application of geopressured heat to industrial and agricultural processes.

The technical and economic feasibility of systems proposed for the extraction, conversion, and utilization of geopressured energy are examined in relation to resource properties. Concepts for the conversion of the mechanical and thermal energy components to electricity are discussed, and several approaches to nonelectric energy utilization are noted.

A brief review highlights the importance of legal and institutional issues that may impede the development of geopressured resources. It is concluded that a better understanding of geopressured resource characteristics is prerequisite to the resolution of most outstanding concerns, both technical and nontechnical.