A new study co-authored by researchers at Harvard Kennedy School's Belfer Center for Science and International Affairs, Duke University’s Nicholas Institute for Environmental Policy Solutions, and the University of Calgary provides the first comprehensive representation of changing water consumption patterns associated with fuel extraction and power generation.
The study, titled "A Spatiotemporal Exploration of Water Consumption Changes Resulting from the Coal-to-Gas Transition in Pennsylvania," examines the water implications of Pennsylvania’s energy extraction and generation choices. In this study of Pennsylvania's coal-to-gas transition at the sub-basin level, the researchers developed a method that uses available data to estimate monthly water consumption associated with fuel extraction and power generation within Pennsylvania watersheds from 2009-12.
The study concludes that extraction of coal and natural gas and power generation from both fuels contributed to a yearly 2.6 to 8.4 percent increase in water consumption in Pennsylvania during the early stages of the coal-to-gas transition. However, impacts varied across the state as some areas experienced no change or large decreases in water consumption, according to a new working paper
“We found that while more water is being consumed in Pennsylvania for natural gas energy extraction and generation -- roughly equivalent to water use in a town the size of 61,000 -- coal is being used less so less water is being used for its extraction and generation,” said Lauren Patterson, a policy associate at the Nicholas Institute and the study’s lead author. “These findings show how examining both energy extraction and generation sectors, as well as zooming down to a scale even smaller than the state level, can aid decision-makers in defining consumption impacts as a result of the coal-to-gas transition.”
The paper combines publically available location data from the Pennsylvania Department of Environmental Protection, FracFocus, the Mine Safety and Health Administration and the U.S. Energy Information Administration to estimate water consumption related to both energy extraction and electricity generation at a higher scale than previous studies.
It finds that water consumption varied widely depending on the presence of natural gas resources and power generating infrastructure. During the four-year period, water consumption increased 67 percent for natural gas generation, particularly around the metropolitan region of Philadelphia and Pittsburg, while water used for hydraulic fracturing increased over time in southwest and northeast Pennsylvania.
Water consumed by coal power, on the other hand, decreased 13 percent in the four years. And in some areas of the state, increased water use from hydraulic fracturing was offset by the decrease in water consumption for power generation as plants switched from coal to natural gas.
"Our work provides a case study demonstrating the importance of accounting for the linkages between different production sectors to understand the impacts of technology developments on the environment,” said Laura Diaz Anadon, assistant professor of public policy at Harvard Kennedy School's Belfer Center for Science and International Affairs and visiting senior lecturer at University College London's Department of Science, Technology, Engineering and Public Policy. “The difficulty we had estimating the magnitude of water consumption changes in Pennsylvania for the fuel extraction and conversion industries in the recent past also provides an indication of how hard, but necessary, it is to do this prospectively.”
The study is available here. See the interactive map and chart showcasing the data:www.nicholasinstitute.duke.edu/hydraulic-fracturing.