Water
Lifecycle Water Footprint of Alternative Transportation Fuels
The project will assess and characterize the water footprint of alternative transportation fuels, including electricity, natural gas, biofuels, hydrogen and unconventional fossil fuels. We will adopt a lifecycle perspective that includes resource extraction / farming and transportation; fuel production and transportation / transmission; and operation of the vehicle. For each energy carrier, different feedstocks and technologies will be considered. For example, electricity generated from natural gas, coal, geothermal, solar, and nuclear power have considerably different water demands.
Our characterization of the water footprint takes into consideration the fact that, unlike carbon footprint which can be defined in terms of tons of CO2 reduced per unit energy or vehicle mile; water footprint cannot be represented by a single metric Rather, it matters greatly where the water is consumed, what type of water is consumed (e.g. surface water vs. groundwater, or recycled water vs. fresh water), how (e.g. withdrawals vs. consumption), when (e.g. seasonality), how fast, and the quality of the water after use. In other words, the lifecycle water footprint analysis will explicitly takes into account the spatial and temporal aspects of water impacts.
The analysis will then be extended to examine the marginal impacts of substitution of conventional petroleum fuels by alternative fuels. While the carbon reduction potential policies like Low Carbon Fuel Standard in California and Renewables Standard at the federal level has been analyzed in some detail, the impact of these standards on water availability and quality relative to BAU is considered to be potentially large, but highly uncertain.
Results of this analysis will highlight limitations imposed by water shortages to achieve higher penetration of some alternative fuels. Ultimately, we expect our research will provide a planning tool for policy makers to analyze the tradeoffs between carbon reduction and water impacts.
Principal Researchers
- Gouri Shankar Mishra, Student (Institute of Transportation Studies, UC Davis)
- Gary Chan, Student (Institute of Transportation Studies, UC Davis)
- Sonia Yeh, Research Scientist (Institute of Transportation Studies, UC Davis)
Donald Gautier, USGS geologist, presents on petroleum in the arctic