(124d) Development of Direct-Use Projects

A geothermal direct-use project utilizes a natural resource ? a flow of geothermal fluid at elevated temperatures, which is capable of providing heat and/or cooling to buildings, greenhouses, aquaculture ponds and industrial processes. Geothermal utilization requires matching the varied needs of the user and characteristics of the resource in order to development a successful project. Each application is unique and guidelines are provided for the logical steps required to implement a project. Recommended temperature and flows are suggested for spas and pools, space and district heating, greenhouse and aquaculture pond heating and industrial applications. Guidelines are also provided for selecting the necessary equipment including downhole pumps, piping, heat exchangers and heat convectors. The relationship between temperature, flow rate and the use of heat exchangers to provide heat to a space with hot water or hot air is provided for a number of applications, with suggested ?rules of thumb?. Combined heat and power projects are also suggested as an alternative to maximize the utilization of a resource and improve the economics of the project.