1. Climate-Friendly Wastewater Solutions Navigating the Wastewater-Energy-Climate Nexus

2. Power required for urban water and wastewater management is significant. (Watts per person) Adapted from Carns, K. (2007) and Daigger, G. D. (2008).

3. Thermal energy present in wastewater is a potential energy resource that is untapped. Wastewater is inherently warm: 15.6°C in U.S. (Metcalf & Eddy, 2003) Heat Exchanger Cold Tap Water, 6.1°C (Lewisburg, PA, 2/3/09, 6:00pm) Collection SystemTo hot water heater 75 gal/day at 9°C Δt, 30% efficiency = 18 W/person

4. Microbial fuel cells tap into the energy wasted in the electron transport chain of microbes. Limited by hydrolysis of particulate material and efficiency of using the liberated electrons (20%) O 2 CO 2 Wasted Energy J.S. Guest ‘05, S. Naha, J. Sole, N.G. Love, I.K. Puri, M.W. Ellis, Virginia Tech, Photo Courtesy of J. S. Guest

5. Source separation of urine overcomes some of the obstacles of water reclamation and reuse. ~80% of N, ~ 50% P Majority of pharmaceuticals, hormones, etc. (Larsen & Gujer, 1996, Henze and Ledin, 2001) Nutrient recovery, fertilizer Residential non- potable reuse Decentralized or on-site treatment

6. A cautionary tale: We must evaluate consequences of progress. 300X GWP of CO 2 Energy Information Administration, U. S. DOE, Report#:DOE/EIA-0573(2005), Emissions of Greenhouse Gases in the United States, 2005 Gilmore, Smets, Terada,Garland, Lackner, and Love (in preparation).

7. Kevin Sullivan, Eagle Eye Inspections, Inc., Washington, Mo., http://www.thisoldhouse.com/toh/photos/ 0,,1614615_1349263,00.html

8. Image credits: – Wastewater treatment plant – Peppers Ferry Regional Wastewater Treatment Facility, Radford, VA, photo by K. Gilmore – Power Substation - http://www.sgceng.com/content.php?sectionID=262&mode= – Sky-scape (public domain) http://commons.wikimedia.org/wiki/File:Field,_corn,_Liechtenstein,_Mountains,_Alps,_Vaduz,_sky,_clouds,_landscape.jpg – Microbial Fuel Cell – photo courtesy of J. S. Guest, Univ. of Michigan. – Urine separating toilet – http://www.novaquatis.eawag.ch/index_EN – Plywood septic tank – Kevin Sullivan, Eagle Eye Inspections, Inc., Washington, Mo., http://www.thisoldhouse.com/toh/photos/ 0,,1614615_1349263,00.html

9. Peter Stryker, Associate Professor of Mechanical Engineering— “Energy Consciousness and Conservation” Tom DiStefano, Associate Professor of Civil and Environmental Engineering—“Renewable Energy from Waste Materials” Carl Kirby, Associate Professor of Geology—“Geothermal Energy” Kevin Gilmore, Visiting Assistant Professor of Civil and Environmental Engineering—“Climate-Friendly Wastewater Solutions” Questions for the panel