This document discusses water use and consumption for hydropower generation. It notes that hydropower water usage must account for multiple uses of dams and downstream impacts, as with other generation technologies. There have been limited studies on water use for hydropower specifically. The document proposes a conceptual framework and methodology to expand analyses of water use for all energy generation technologies, including hydropower. Key aspects that need definition and consideration are consumption, water use, losses, supply chain impacts and downstream effects. Case studies would need to account for hydrological, climate and infrastructure factors as well as grid integration.

1. Water Use and Consumption for Hydropower Presenter: Chris Eaglin Work performed by: Dr Guy Pegram, Chris Eaglin and Kate Laing June 2011

2. Energy and water use Hydropower and water use Water Footprint Methodology Contents of Presentation

3. ENERGY AND WATER USE

4. International consensus is that water scarcity will increase globally in next 20 to 30 years, with profound social and political implications. Water is fundamental to the food an energy sectors. Scarcity drives a need for awareness of the consumption of water and optimising productive efficiency. Energy and Water Use

5. Water and Energy Relationship Water for Energy Energy for Water Source: WEC 2010

6. There have been a lot of attention on the concept of the consumption of water in the production of energy. Water scarcity and drive for optimized use has led to various estimations of the amount of water use per GJ output In thinking about this, there are several considerations: Generation capacity Energy supply chain Attribution of losses. Energy and Water Use

7. A Conceptual Framework Water Downstream Storage

8. Water use in different energy generation technologies has been has been investigated in great detail. The analyses have examined: Coal Natural Gas Biofuels and biomass Wind and Solar The same cannot be said of hydropower (the majority of these studies generally refer to work performed by Gleick 1994). We are proposing a conceptual framework to expand upon analyses of water use in energy generation. This should provide a common matrix for comparing water use in all energygeneration. Literature Review of Energy and Water Use

9. Literature Review of Energy and Water Use Coal fired generation (estimates from Gleick 1994) Consumptive use is 0.8-2.1 m3/MWh (energy conversion only) varies by tech. Natural gas (according to WEC 2010 report) Estimates vary by technology, however gas fired technologies use approximately 0.7 – 3.7m3/MWh (energy conversion) Wind and solar (Gleick 1994) These technologies are generally considered to be the lowest water consumption users (save solar thermal) in terms of water consumption use. Biofuels and biomass (according to UNESCO-IHE 2008 report) Estimations of biomass energy water requirements vary widely based on location and fuel type.

10. HYDROPOWER AND WATER USE

11. From the literature review there are three key issues to consider: There have been limited studies on hydropower Measuring hydropower water usage must take into account multiple uses of dams Downstream impact must be included as with other generation technologies Hydro Power and Water Use

12. Key issues that require clarification and debate: A set of definitions for hydropower and water usage. An appropriate and relevant methodology. A broad selection of dedicated studies that reflect different aspects of hydropower stations. Contributing to the Literature

13. WATER USE METHODOLOGIES

14. Considerations for definitions Consumption Water use Water loss (net versus gross loss) Supply chain impacts Downstream impacts Water Footprint

15. Methodology issues All metrics look at water used over energy generated For hydropower this number is reservoir evaporation Three primary methods Gross evaporation/energy generated (Gross reservoir evaporation – previous environment evaporation)/energy generated (Gross reservoir evaporation – precipitation)/energy generated Important to treat hydropower water use like other technologies by input/output including supply chain

17. Structure of the hydropower system

18. Uses of hydropower scheme