Existing Solutions

Biofuel, feedstock, irrigation, water footprint, LCA

technical

Analytical

Several features of water resources make their impacts difficult to quantify using conventional Life Cycle Assessment (LCA) approaches. Water consumption varies spatially and temporally, different water sources are not necessarily commensurable, and impact depends on the state of the resource base that is drawn upon. Despite these difficulties, comprehensive water LCA, if performed correctly, can be a useful tool in land use, policy planning, and mitigation decisions.

Life cycle inventory must be comprehensive, taking account of irrigation from varying sources, consumptive use of rainwater, and pollution effects. Life cycle inventories should quantify the net effect of activities, accounting for the consumption associated with any prior or displaced land uses rather than only quantifying consumption in absolute terms. Finally, assessment must be spatially and temporally discrete in order to sufficiently capture the heterogeneity of water use and impact.

The impact associated with water use depends entirely on the prior state of the affected resource base. LCA can make use of quantitative resource stress metrics to characterize consumption values given local conditions. Tools applied for this purpose should account for climatic variability, the non-linear relationship between water scarcity and stress, and the fact that sufficient environmental flows need to remain intact to maintain a stable ecosystem. Several methods can be used to estimate environmental water requirements (EWR) for a given ecosystem. Methods proposed by Smakhtin (2004) and Richter (2011) can provide a first-order assessment, while the more data-intensive Environmental Limits of Hydrological Alteration (ELOHA) approach (Poff, 2010) should be employed if possible in ecosystems where environmental flows are severely restricted.

Various iterations of the approach described above have primarily been implemented in academic analyses (Fingerman et al, 2011; Water Footprint Network, 2010, Pfister, 2009). However, several international organizations, such as UNEP and the Water Footprint Network, have worked to further develop this technique and to implement it in policy contexts.

Who had initiated the project? What were the stakeholders’ drivers?
This solution is more a method than a project. It was initiated by Arjen Hoekstra, Vladimir Smakhtin, and Stefan Pfister, and in biofuels by Kevin Fingerman.

Who has ensured follow-up of the solution at the local level?
The method is being implemented at the local level by, among others, the World Wildlife Fund, UN Environment Program, and the Water Footprint Network

Key question your solution aims to answer (i.e. if your Solution is the answer, then what is the question) and how does that fit with the target?
“How can analytical tools be designed to guide biofuel and other renewable energy development that is sustainable from the perspective of water resources?”

How does the solution contribute to the target’s effective implementation and attainment?
The comprehensive life cycle assessment approach described here can be (and has been) applied in the planning process to ensure that policy and technology decisions related to biofuels do not result in unacceptable outcomes for the impacted water resource bases.

What are the solution’s key outputs and what impacts did the solution have given the investment level (not only financial)?
The key outputs are policy and planning recommendations. This solution is relatively inexpensive, requiring no infrastructure investment – only the time and effort of qualified analysts.

Can the solution continue to deliver tangible impacts on the long term?
Absolutely. Its benefit will only increase as methods are perfected and further data are collected over time.

Were this solution to be more broadly implemented, we would expect that over time decision-makers would incorporate nuanced water accounting as an integral part of energy planning and policy processes. As a result, energy production would be more efficiently planned from a water resource perspective and would less frequently create unsustainable water quantity or quality outcomes.

Given your experience, who would / should be most interested in this Solution and why? How will it help them?
Decision-makers in government and industry would stand to benefit from this Solution as it would help them better understand risks to bioenergy development that might result from unsustainable use of water resources.

In what context do you think this solution could / would work best and why?
This Solution works best where large-scale bioenergy expansion plans are being developed and negotiated. In the early planning phase for both policy and industrial processes, new information is sought and sunk costs are sufficiently minor for efforts to be redirected if necessary. If considered at this point, potentially detrimental water resource outcomes could be avoided

Given your experience, what would be needed to upscale this solution, for example to a political or/and a regional level?
The most important factors in upscaling this solution are data availability and political will. Without spatially and temporally resolved water use and availability data, sufficiently nuanced impact analysis cannot be conducted. These data must be collected and made available by public water and energy agencies in order for global, regional, and local assessments to take place.

Decision-makers must perform the type of comprehensive analysis described above before developing bioenergy expansion plans or incentives. This will create a top-down dynamic in which industry must sufficiently assess impacts in order to ensure compliance and access to incentive programs. Private sector stakeholders cannot necessarily be expected to act unilaterally to ensure sustainable use of water resources except where water is so acutely scarce as to act as a physical constraint to their operations.

What tips and guidance (dos and don’ts) would you give to others interested in applying this solution in their own context?
Life cycle assessment, performed as described above, can be an important tool for identifying regions of concern for water quantity and quality. However, several important water resource impacts of bioenergy expansion will not be captured through this type of quantitative, analytical approach. For example, cumulative effect of changes in a watershed, impact on key habitats, and adaptability of local communities will not be adequately characterized using this tool alone. Detailed, ground-level study can complement LCA approaches once probable impacts of concern have been identified through this high-level analysis.

What is the minimum investment necessary (in terms of human resources, time, energy, infrastructure, financial resources, political will, etc.) in order to effectively implement this solution?
One of the strengths of this solution is that it can be implemented at any scale and still deliver benefits. Simply incorporating the elements of this analytical approach will inform policy or technology planning processes. This need not require much investment at all. Significantly incorporating this approach in larger scale planning processes will require more investment of time and resources, and will carry attendant benefits.

The Water Footprint Network, the International Water Management Institute, and the World Wildlife Fund are important proponents of elements of this approach. They are supporting its implementation through various avenues.

Roundtable on Sustainable Biofuels (Coordinator of TSG 2.3.7)

Anne-Sophie Dörnbrack (anne-sophie.doernbrack@epfl.ch)

Sébastien Haye (sebastien.haye@epfl.ch)