The water-energy-food nexus of production from shale oil, shale gas and oil sands

Unconventional fossil fuel resources have recently emerged as new important energy sources and they are expected to play a fundamental role in meeting energy demand in the near future. We consider global shale oil, shale gas and oil sands assessing consequences on the Water-Energy-Food security Nexus. Shale resources are globally abundant and widespread. Extraction of shale oil and natural gas is performed through hydraulic fracturing, a water intensive process that is not free from environmental and social impacts. It is unclear to what extent and where the development of shale resources could compete with water and food security. Here we consider the global distribution of known shale deposits suitable for oil and gas production and evaluate the impacts on water resources for food production and other human and environmental uses in the same region. We find that 39% of world’s high quality shale deposits is located in areas affected by water stress and 7% is situated in regions where irrigation is expected to meet the growing food demand. In these regions shale oil and gas production would likely threaten water and food security. These results highlight the need for adequate policies to avert social, economic, and ecological consequences of shale resource extraction. Oil sands deposits account for a third of globally proven oil reserves, extend over large natural areas, and have extraction methods requiring large volumes of freshwater. Little work has been done to quantify some of the environmental impacts of oil sands operations. Here we examine forest loss and water use for the world’s major oil sands deposits. We calculate rates of water use and forest loss both in Canadian deposits where oil sand extraction is already taking place and in other major deposits worldwide accounting for ≈93% of global oil sand reserves. We estimated that their full exploitation could result in 1.31 km3 yr-1 of freshwater, 8700 km2 of forest loss, and 383 Mtonne CO2eq yr-1 in greenhouse emissions. The expected escalation in oil sands extraction thus portends extensive environmental impacts. While unconventional fossil fuels extraction have multiple environmental impacts, there have however been substantial economic benefits that bring to an ever-evolving technological innovation, which is lowering environmental impacts. Furthermore, energy security of some countries has been strengthen. Thus there are clear and ongoing tradeoffs between economic development, energy, and the environment.