Water, Energy and Sustainability Bruce A. Macler, PhD USEPA Region 9 macler.bruce@epa.gov 415 972-3569
Changes are A’Comin’... Climate change will impact water Warmer air, warmer water Water quality problems Biological changes Change in location and amount of precipitation Increased storm intensity Sea level rise and boundary changes Change in ocean characteristics
Likely Problems for Drinking Water Inadequate storage Loss of snowpack “reservoirs” Big storms and timing shifts Rainfall shifts to the north, drought in south Reduced groundwater recharge Decreased surface flows Waterbody boundary shifts and losses Rising sea level Increased evaporation Changes in flow patterns
More Likely Problems Water quality and biological changes Decreased dissolved oxygen More algae and bacteria Ecosystem shifts or collapses Sedimentation and nutrient increases from increased wildfires More treatment may be necessary Concurrent changes in energy availability
Water and Energy Interdependencies Energy generation Hydroelectric power Cooling water Energy use Pumping (source to tap to WWTP to source) Treatment Drinking water Waste water End users Water heating
Water and Energy Generation Hydropower generation Themocooling of generators Water use in extraction and mining Use in emission controls Use in alternative fuel generation Ethanol Biodiesel
A Little Quantitation on Use CA uses about 26,000 GWh of electricity/ year for the water sector ~10% of all power use Water supply conveyance and distribution pumping use about 12,000 GWh/yr Treatment (DW and WW) uses about 1400 GWh/yr End-use is about 12,500 GWh/yr Mostly heating and cooling Irrigation uses about 2300 GWh/yr
EPA Interests and Concerns EPA Climate Change Strategy Addresses water and energy Emphasizes research, forecasting EPA Sustainability Initiative Four (five) key pillars Emphasizes proactive management
Sustainability in the Face of Change EPA Sustainability Initiative Better management Full cost pricing Efficient water use Watershed approaches *Energy efficiency
Water-Energy Efficiency Greatest long term opportunities are from reducing energy used for pumping Source to treatment to customer Waste to treatment to discharge Reducing end user energy use is vital Embedded energy savings from water conservation may be ephemeral Conserved water will likely be used elsewhere
Reducing Conveyance Energy Use Optimize pump efficiency and operational efficiency Increase use of local or closer resources Water trading may be useful Increase local seawater and brackish water desalination Treatment may be more energy efficient than pumping from a distance Increase desalination of co-produced water
Water Sector Energy Efficiency Reduce energy use in transmission Audit and reduce energy loss to flow resistance in distribution lines Address inefficient pump sizing and operations Address inefficient distribution and storage configurations Improve storage mixing to reduce water age and stratification
End User Conservation The demise of traditional water heaters? Energy-efficient water-using appliances Washing machines Dishwashers Commercial equipment Conserving the energy value of hot and cold water
A Useful Tool: Full Cost Pricing Analysis of source-to-tap energy use (as distinct from actual energy costs) can illuminate hidden/ subsidized costs For example, might show that desalination in LA more energy efficient than pumping from Lake Shasta Full-cost pricing can improve efficient marketing
Crystal Ball Gazing Climate change will alter water resources Climate change will affect a lot of other things May lead to mass migration Water and energy availability and cost may influence this Cost of fuel will be going up, too Likely to affect desire for hydroelectric May lead to reconsideration of urban-suburban structure