Response to Comment on 'Comparison of Water Use for Hydraulic Fracturing for Unconventional Oil and Gas versus Conventional Oil'

摘要

The general perception is that hydraulic fracturing (HF) for oil production in unconventional reservoirs uses excessive amounts of water to produce energy. Our analysis of water demands over the production life of conventional oil wells as compared to unconventional oil wells contradicts the "general perception". Results of our analysis based on oil production to date and estimated ultimate recovery in the two main oil producing plays in the U.S., Eagle Ford and Bakken, suggest that HF water use is within the lower range of water used for oil production from conventional reservoirs. However, Lampert, in this comment, suggests that one must account for potential water use during the mature production phase from unconventional reservoirs, and, in particular, enhanced recovery, which could significantly increase the currently estimated water use. Therefore, it would be inappropriate to compare HF water use at well completion in unconventional plays with water use over the life of wells in conventional plays, which include water use for primary (drilling), secondary (water flooding), and tertiary (steam, chemical, or CO_2 injection) recovery.