Argonne LCA study finds many alternative fuels consume more water than petroleum and natural gas fuels
09 March 2016
Researchers at Argonne National Laboratory have analyzed the water consumption for transportation fuels in the United States using an extended lifecycle system boundary that includes the water embedded in intermediate processing steps.
In a paper published in the RSC journal Energy & Environmental Science, they compared the water consumed per unit energy and per km traveled in light-duty vehicles. They found that many alternative fuels consume larger quantities of water on a per km basis than traditional petroleum and natural gas pathways. The authors concluded that it will be important to consider the implications of transportation and energy policy changes on water resources in the future.
Energy production processes consume water resources and accelerate fluxes of water from land surfaces to the atmosphere. Increases in population, energy and food demand now strain previously abundant sources of water. For these reasons, it is important to characterize the relationships between consumption of water resources and the production of energy.
… Transportation fuels are produced using interconnected pathways composed of numerous individual production processes. Many of these production processes generate intermediates that are later consumed for the ultimate purpose of generating transportation. Each process in a pathway may consume water resources, so it is necessary to analyze the water consumed throughout the pathway to understand the net impact that a fuel will have on water resources. For example, biodiesel and ethanol production consume water in both the agricultural operations used to produce biomass and in the conversion of the biomass to fuel; thermoelectric power generation consumes water in fuel cycle operations and cooling in thermoelectric power plants; hydroelectric power plants require water-consuming reservoirs to generate electricity; hydrogen fuel cells consume water as a feedstock for the fuel and for cooling excess energy generated by the process; petroleum and natural gas require water for recovery and subsequently for processing.
… LCAs [life cycle analysis] of water consumption are challenging to perform due to differences in definitions and terminology associated with water data. … The goals of this study were to develop a comprehensive baseline LCA of water resource consumption associated with transportation fuel production, highlight the uncertainties and implications in the results, and identify important outstanding gaps in the data. There have been other LCAs performed on water consumption associated with transportation; however, these analyses ignored the water embedded in many intermediate resources such as transportation fuel and intermediate chemicals or utilized economic input–output modeling to fill process data gaps.
—Lampert et al.
The Argonne team developed an extensive inventory of process-level water consumption factors for the major transportation fuel pathways in the US consistent with the structure in the lifecycle analysis tool GREET. They used the inventory with the GREET framework to estimate the anthropogenic-induced water consumption associated with the various transportation fuels.
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| Well-to-wheels pathways for transportation fuels and passenger vehicles analyzed by Lampert et al.. Click to enlarge. |
System boundaries for the life cycle water consumed in the production of the transportation fuels in the study included mining and recovery operations; agricultural production of biomass; agricultural chemicals manufacturing; biofuel conversion; crude oil and natural gas refining and processing, and transportation and distribution. Life cycle water consumption was computed for each fuel pathway using the 2014 version of GREET.net.
Their findings included:
Fossil fuel pathways generally have the least impact on water resources. Petroleum-based gasoline and diesel consume slightly more water than CNG because of the water consumption associated with enhanced recovery technologies.
Corn and soy biofuel production show the largest water consumption impact among all the fuels with the exception of electricity from hydropower. Water consumption associated with irrigation for a particular crop may be much less than or much greater than the US average, they noted.
electricity generation pathways have both the smallest (wind) and largest (hydropower) impact on water resources. Thermoelectric power generation pathways consume more than twice the water of fossil fuel pathways primarily for waste heat dissipation.
Using dry cooling technologies would bring electricity water consumption estimates into a similar range as the baseline fossil fuels, although these technologies carry both a capital and energy penalty.
More than 70% of this water is associated with evaporation from hydropower reservoirs. Because electricity is a fundamental input for essentially all the other pathways, a detailed analysis of the water consumption associated with hydropower is in need of further characterization, the researchers said.
Pathways for centralized production of hydrogen fuel showed similar water consumption footprints to the thermoelectric pathways on an energy basis. A large portion of the total is associated with water embedded in electric compression than can be traced to hydropower generation. Processing and cooling constitute the other major contributors to the H2 pathways.
In terms of water liters/100 km, compressed natural gas vehicles show the lowest burden on water consumption—the majority of the water is associated with electric compression of the fuel and not with the recovery process. Reforming natural gas to H2 for use in a FCEV more than doubles the water consumption intensity of transportation.
Coal or biomass-based gasification in central facilities is expected to consume a similar amount of water as the SMR-based H2 pathway.
BEVs were estimated to consume almost twice the water as the E10 baseline on average in the US. However, electricity-based transportation exhibits high variability depending on the regional electricity mix.
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| Life cycle water consumption (L per 100 km) associated with transportation in light-duty vehicles from select pathways. Lampert et al. Click to enlarge. |
Moves towards alternative fuels appear to have a greater impact on water resources than fossil fuels. Energy and environmental policy should consider the implications of alternative vehicles on water resources when planning changes to the transportation and energy infrastructure. The values outlined in this study should not be interpreted as absolute inputs for specific projects since many processes (e.g., agriculture, mining) exhibit high degrees of spatial and temporal variability. Actual projects must therefore be evaluated on their specifics and not on national or regional averages.
—Lampert et al.
The research was supported by the Bioenergy Technologies Office, Fuel Cell Technologies Office, and the Vehicle Technologies Office of the Department of Energy’s Office of Energy Efficiency and Renewable Energy.
Resources
David J. Lampert, Hao Cai and Amgad Elgowainy (2016) “Wells to wheels: water consumption for transportation fuels in the United States” Energy & Environmental Science doi: 10.1039/c5ee03254g
'Argonne LCA study finds many alternative fuels consume more water than petroleum and natural gas fuels' ..
whereas pumping billions of gallons of water into oilfracting earth is less consuming
This study has been Republican congress initiated, funded, dictated, and approved.
Posted by: kelly | 09 March 2016 at 07:31 AM
Fossil fuels from Tar sands may be the water usage champion but is not on the list?
We are lucky (in our area) because our 95% Hydro + 5% Wind electricity sources have plenty of water from 1,000,000+ lakes and almost as many streams and rivers.
Hydro cycles water just as nature does and wind uses the least water per kWh? We could use those 2 sources for another century and more.
Posted by: HarveyD | 09 March 2016 at 08:14 AM
This study proves studies can be made to conclude whatever you want them too if you use the right assumptions up front. Always, read the assumptions carefully. This particular study links the evaporation of water in dam reservoirs used for hydropower with charging BEVs and if you want to go even further, you could link water loss in fracturing shale oil to natural gas recovery used in power plants to produce electricity to charge BEVs...brother...a badly flawed study because it is way too broad in it's assumptions.
Posted by: Lad | 09 March 2016 at 08:26 AM
You're so right Lad. Studies can be distorted with choice of assumptions.
Posted by: HarveyD | 09 March 2016 at 10:27 AM
Good for Argonne. It's nice to see them defend dirty old industries rather than discovering better future paths. They are controlled by congress though, so I suppose if they actually discovered new and better ways of powering the future their funding would be cut.
Posted by: Brotherkenny4 | 09 March 2016 at 11:07 AM
Cellulose bio fuels made from corn stover do not use more water nor land, they clean the land so crops grow more quickly in the spring. With a cover crop in winter they get more income and the next crop has more sun and warmer soil earlier.
Posted by: SJC | 09 March 2016 at 12:12 PM
I agree with this study. It's been done before with similar results. But they forgot something. Oil and gas's impact on water sources. Less water may be used in the life cycle in natural gas, gasoline and diesel. However, they forgot water (groundwater and surface) supplies impacted enough from operations to be rendered non potable. For instance, shale fields are impacting groundwater. In several shale plays alternative water supplies are required for local residents who depend on private or public groundwater wells. That' water is pretty much bad for a generation. Of course agriculture and mining and nuclear power are doing the same to water supplies. Agriculture impacts groundwater and surface water from fertilizer applications to pesticide and herbicide chemicals. Roughly 50 percent of the corn grown in the US is being used for ethanol fuel. A lower fraction for biodiesel products.
Anyway, interesting stuff to think about.
Posted by: plus.google.com/116408766279735036879 | 09 March 2016 at 01:49 PM
I don't think they are doing a hatchet job.
There are a host of metrics which need to be optimised, and water is just one of them.
And also, if the assumptions are altered a bit, then the conclusions change a lot.
The big stand out is hydro, and evaporation.
It is not entirely clear that evaporation from the reservoirs is always and entirely a bad thing, and in any case the really big user is agriculture, not energy generation.
Posted by: Davemart | 09 March 2016 at 01:50 PM
A reservoir can lose 5 feet of water per year, calculate how many acres and you see how many acre feet go to that versus agriculture. Power plant cooling towers in the U.S. use almost as much water as farming, a power plant uses 25 gallons per kWh for cooling, we need better ways.
Posted by: SJC | 09 March 2016 at 03:36 PM
I also read that the Ivanpah solar thermal power tower uses less water than 2 holes of a golf course, they use dry cooling. This was stated by the Secretary of Energy recently.
Posted by: SJC | 09 March 2016 at 03:39 PM
SJC:
My understanding is that although the gross water draw by the power industry is very high, a heck of a lot of it is returned, slightly warmed, so the net draw is way lower, certainly compared to agriculture although not compared to personal use.
Posted by: Davemart | 10 March 2016 at 03:07 AM
I didn't want to turn this into yet another thread about fuel cells, but some of their stuff in that area seems questionable and heavily dependent on the assumptions made:
'Pathways for centralized production of hydrogen fuel showed similar water consumption footprints to the thermoelectric pathways on an energy basis. A large portion of the total is associated with water embedded in electric compression than can be traced to hydropower generation. Processing and cooling constitute the other major contributors to the H2 pathways.'
So what about decentralised production?
I don't understand their notions about the high energy costs of compression either, which is a relatively small part compared to the energy in the hydrogen.
They presumably are assuming that it is liquified for transport by tanker, which does take a lot of energy, when a lot of it is:
Produced locally.
Remains as a gas, not a liquid, and needs way less compression.
As for cooling and so on:
'Additionally, fuel cell technology delivers extraordinary water savings as it requires no water beyond an injection of 240 gallons at start-up. Compared to the average water demands of California power plants, it is estimated that Honda will save more than 3.25 million gallons of equivalent water used per year.'
http://fuelcellsworks.com/news/2013/03/22/american-honda-installs-stationary-fuel-cell-system-that-will-produce-a-megawatt-of-clean-energy-reduce-co2/
So they seem to be basing their conclusions on the most inefficient pathways they could dream up, and to have ignored all the efficient ones.
Perhaps I was mistaken, and it is a hatchet job.
In any event, it seems to not be even-handed enough to be of much use.
Posted by: Davemart | 10 March 2016 at 03:16 AM
Once-through cooling is very economical of water; in temperate-zone autumn conditions roughly half of the heat is dissipated by radiation, and this fraction increases as the ambient temperature increases. The major ecological concern is exceeding the temperature tolerance limits of wildlife during heat waves.
Posted by: Engineer-Poet | 10 March 2016 at 11:29 AM
Those estimates are for evaporative cooling towers.
Posted by: SJC | 10 March 2016 at 02:01 PM
I see the Obamaloids coming out once again to link the Evil GOP to anything with fossil fuel. Facts is facts: We have known for some time that biofuel and electrification of automotives generate miserable EROEI compared to mere conservation and efficiency upgrade of fossil fuel tech; That levelized costs of these alternative projects can't even ride out fluctuations in the costs of oil and gas (note that for ethanol producers in 2008 gasoline costs rose very much, but corn costs rose even more, derailing the whole industry); That even the EROEI on massive efforts to produce solar panels and rare earth motors takes years to recuperate and produce significant GHG savings.
So why should we be surprised that these alternative strategies are water hogs?
FYI -- It's estimated that power generation constitutes 30% of municipal water consumption; That corn requires massive and constant feeds of water, not to mention vast tillage to accommodate root systems, making it among the least suitable crops I know for polyculture or crop rotation. It even pays to feed cattle wheat and barley, so why subsidize corn? The situation might improve if power plants provided cogenerative heat to manufacture ethanol -- But since Congress has been controlled by Dems for most of the last 70 years, and since Obama in particular has waged war on coal, then there goes another sensible idea.
Alarming, isn't it, that Hillary and Bernie now public gloat in their debates how they would put fracking out of business. Ironically, the productivity of this industry has gone up about 50% per gallon of water in less than 10 years, notwithstanding that steam recovery of petroleum, fervently discussed in the 70's, is going out of style. The water used in fracking is mostly remediable in sewage treatment plants. And I suspect that those lawsuits in PA and NY against Cabot Industries now making the news are typical tortlaw hooey, proving no definitive connection between fracking and methane gas leaks.
PS -- now that you got me rolling about Hillary, it's worth mentioning that for all her hooplah against the "GOP" appointed city trustee of Flint MI,and the governor, the federal EPA is as negligent, if not more negligent than any party for that mess, having failed to provide analyses and warnings about a certain natural body of water within federal jurisdiction, called Lake Huron.
Just sayin'. But have a nice day.
Posted by: kalendjay | 10 March 2016 at 03:36 PM
Grow the 100 million acres of corn that is grown now, much of the processed food in the supermarkets uses corn. Now use the corn STALKS for fuel, no extra land nor extra water.
Posted by: SJC | 10 March 2016 at 04:29 PM