It is generally assumed that the higher the reservoir temperature the lower would be the net power capacity available from a well drilled into the reservoir. This paper shows that this is true in theory, but not necessarily so in practice. For the temperature range of 100?C to 180?C, typically the wells are pumped and binary-cycle power generation is the norm. For this range in reservoir temperature, we have estimated the available net power capacity per well assuming the use of a conventional line-shaft pump as well as an electric submersible pump with due regard to the production rate limit of a commercial pump and a parasitic power limit of one horsepower. We have assumed typical generation efficiency of a binary cycle power plant. In this temperature range, the net power capacity of a well was relatively to insensitive to the wellís productivity index, and largely insensitive to static reservoir pressure (except when a well is severely sub-hydrostatic).

For reservoir temperatures greater than 180?C the well was assumed to be self-flowed and power was assumed to be generated in a flash-cycle or hybrid power plant. The well performance was evaluated through wellbore simulation. A productivity index range of 1 to 10 liters per second per bar was considered as well as typical efficiency levels of flash-cycle and hybrid power generation.

The above assessments were conducted for the temperature range of 100?C to 350?C. It is concluded that for all practical purposes the net power capacity of a well increases monotomically with temperature up to 180?C, which is the upper limit in temperature for conventional production pumps. For a reservoir temperature of 180?C to about 220?C, net power capacity of a well remains very sensitive to the wellís productive index but is generally higher for a higher temperature. For dry steam reservoirs, net power capacity of a well is a unique function of the wellís productivity index.

The implications of the results of this study for the development of conventional as well as enhanced geothermal systems are discussed.

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