Some Results of a Long-Term Flow Test of a Hot-Dry-Rock Reservoir

摘要

Results from a 286-day flow test of a new hot dry rock reservoir created at Fenton Hill in the Jemez Mountains in northwest New Mexico are presented. The reservoir was created by fracturing an interval of granitic rock at a depth of 2.93 km (9620 ft). The system was formed from a recemented wellbore pair used to create the first hot dry rock reservoir. The undisturbed rock temperature at the bottom of the new reservoir was 197 exp 0 C. With a nominal outlet flow of 5.7 x 10 exp -3 m exp 3 /s (95 gpm), the reservoir showed a thermal drawdown of about 8 exp 0 C. A preliminary estimate of the heat transfer area is 45,000 m exp 3 (480,000 ft exp 2 ). The water loss rate to the formation was 4.6 x 10 exp -4 m exp 3 /s (7 gpm). The flow impedance was 1.6 GPa s/M exp 3 (15 psi/gpm). The results of the flow test show that in comparison with the earlier smaller hot dry rock system at the same site, the large increase in heat transfer area was accompanied by only a small increase in the water loss and with the impedance staying essentially constant. (ERA citation 06:031904)