1. 2011 DOE Biomass Program Anaerobic Digestion/ Combined Heat & Power Concept Development Project EE0000616-DOE February 2, 2011 Frank Hartz, Project Manager Rob Taylor, Energy Manager Washington Suburban Sanitary Commission Beverley Stinson, AECOM, Program Consultant This presentation does not contain any proprietary, confidential, or otherwise restricted information

2. Project Overview Project Management Approach Technical Approach Technical Progress & Accomplishments Technology Transfer Critical Success Factors Benefits and Expected Outcomes Project Relevance To Program Goals Questions/ Discussion 2 Agenda 2

3. Recovering the Untapped Energy In Wastewater Biomass 5% of the electrical energy demand in USA is used to treat municipal wastewater This carbon rich wastewater is an untapped energy resource Only 10% of wastewater treatment plants (>5mgd) recover energy Wastewater plants have the potential to produce > 575 MW of Energy Nationwide Potential to capture an additional 175 MW of energy from waste Fats, Oils &Grease Project Focus: Convert wastewater Biomass to Electricity Use innovative technologies to Maximize Energy Recovery Enhance the Environment by reducing nutrient load to waterways (Chesapeake Bay), Sanitary Sewer Overflows and Greenhouse Gas Emissions 3 Project Overview

4. Maximize Sustainable Energy Recovery Reduce Fossil Fuel Derived Energy Use Reduce Biosolids Disposal Volume & Costs Reduce Operating Costs Reduce Nutrient Release to Water Bodies Reduce GHG Emissions 4 Project Goals and Benefits

5. 5 Project Phases Implementation Phase Concept Development Phase Research Technology Transfer Alternative Delivery Methods Engineering Reliability Environmental & Community Benefits Economic Feasibility Detailed Design Public Outreach Construction Commissioning EE0000616-DOE Future Project

6. 6 Project start date - July 07, 2010 Project end date - May 25, 2011 57% complete December 31 Project on schedule and budget Project scope unchanged On schedule to complete Concept Design May 25, 2011 Total project funding –$570,900 DOE share –$198,170 Contractor share Funding –Utilize all funding in FY 2011 ARRA Funding - None Timeline Budget Project Development DOE Biomass Program WSSC Montgomery County Prince George’s County AECOM Consultant Team Project Participants Concept Development Phase – Quad Chart Overview

7. 7 Spending – Plan vs. Actual

8. 8 Consists of 4 Tasks 1.“What are the most viable and cost effective technical approaches by which to recover and reuse energy from biosolids while reducing disposal volume?” 2.“How much energy can be recovered from biosolids?” 3.“What are the potential economic, environmental and community benefits / impacts of each approach?” 4.Recommend best plan and develop a concept design Project Approach Technology Screening & Shortlist Energy Recovery & Disposal Reduction Potential Verification Economic Environmental and Community Benefit Analysis Recommend Approach and Prepare a Concept Design Task 1 Technology Task 2 Verification Task 3 Evaluation Metrics Task 4 Implementation Plan

9. 9 1. “What are the most viable and cost effective technical approaches by which to recover and reuse energy from biosolids and reduce disposal volume?” –Innovative Technology review and assessment. –WSSC interested in optimizing energy recovery –Strike a balance between Advanced Technology & Reliability /Operability –Shortlist of the most feasible and promising was developed; A)Advanced Digestion with combined heat & power recovery B)Drying / Gasification –Both approaches have a range of optimization opportunities Project Approach - Task 1 Technology Evaluation Drying / Gasification Minimizes Waste Volume Anaerobic Digestion / CHP Maximizes Energy Recovery

10. Identify & Evaluate Optimal Technology Building Blocks At the end of Task 1 - Optimal technology process configurations were developed for both fundamental approaches

11. 2.“How much energy can be recovered from biosolids” Extensive Lab & Pilot scale testing and analysis was performed in specialized facilities to verify the true recoverable energy value and inert content of the biomass A)Digestion studies performed with Virginia Tech Specialist; –Assessed the digestibility, gas production & gas quality –Identified some unexpected concerns with the digestibility at one plant –Considering some advanced pre-treatment concepts to maximize energy release from the biomass B)Gasification studies revealed that Biomass has higher than anticipated BTU energy values and a typical inert or residual ash fraction for disposal Testing was key to verifying the energy recovery potential of each approach and in developing design criteria 11 Project Approach– Task 2 Verification

12. EconomicEnvironmentalCommunity / Stakeholder Life Cycle Costs 1. Capital costs 2. O&M Costs 3. Financing Costs 4. Debt Service Costs Environmental benefits ; 1.Reductions in fossil fuel derived energy use 2.Reduction in chemical use and transportation & associated GHG emissions 3.Potential to reduce air pollution 4.Reduce Nutrient release to Chesapeake Bay 5.Reduce Sanitary Sewer Overflows Benefits / Impacts on Operations & Staff 1.Operability / Complexity / Reliability 2.Maintainability 3.Health & Safety 4.Flexibility in product end use or disposal & associated marketability 5.Compatibility with current staff skill base 6.Additional staff requirements 7.Technical support for equipment in North America 8.Lead time for replacement parts and service 9.Potential permit non-compliance risks and impacts – Air, ENR and Biosolids 10.Compatibility with pending or potential regulatory requirements – GHG Emissions 11.Impacts during construction 12.Compatibility with expansion Benefits / Impacts on Rate Payers & Neighbors: 1.Rate reductions or deferment in rate increases 2.Noise 3.Odor 4.Truck traffic 5.Aesthetics / Visual impacts 6.Dust 7.Toxins / Spills Permit requirements 1.Construction 2.Operations Project Approach – Task 3 Triple Bottom Line Evaluation Metrics

13. 13 Project Approach – Task 4 Concept Design & Implementation Planning 4.Select optimal approach and develop; –Concept designs –Mass & energy balances –P&IDs and layouts, –Cost estimates & schedules

14. Technical Accomplishments/ Progress/Results Completed Tasks 1 and 2 on schedule and budget Extensive technology evaluations & lab/pilot testing completed Quantified actual energy recovery potential & limitations Assessed technical, engineering & operability aspects of integrating innovative technologies into US plants Confirmed viability of using FOG for energy recovery Refined design & evaluation criteria with actual plant data Quantified potential air emissions and assessed mitigation technologies Technology Transfer – Water Environment Federation Presentations Technology Screening & Shortlist Energy Recovery Potential Verification Economic Environmental and Community Benefit Analysis Recommend Approach and Prepare a Concept Design Task 1 Technology Task 2 Verification Task 3 Evaluation Metrics Task 4 Implementation Plan

15. Balance Innovation with Reliability / Operability Maximize energy recovery through use of high performance technologies & FOG Robust process with ease of operations & maintenance Work with organizations that have successfully implemented the technologies Reduce operating costs Consolidate facilities to maximize return on investment Optimize capital costs Minimize impact on WSSC rate payers Secure Federal / State funding to reduce payback period Quantify greenhouse gas reductions Reduce truck traffic emissions, noise, nutrient discharges to the Chesapeake Bay, sanitary sewer overflows Engage & Involve; DOE and EPA Federal, State & County Elected Officials State & County Environmental Regulators Identify Optimal Technical Solution Optimize Economic Viability Provide Environmental Benefits Secure Stakeholder Acceptance Success FactorsPlan to Address Challenges and Success Factors

16. 16 Benefits & Expected Outcomes Environmental Benefits Recover 1.7 MW of renewable energy from biomass Reduced Greenhouse Gas production by 5,500 tonnes/ yr Reduce biosolids output by more than 14,000 tons/ yr Reduce lime demand by 4,000 tons/ yr Reduce nutrient load to Chesapeake Bay Reduce 5 MG/ yr Grease discharge to sewers Mitigate potential for sanitary sewer overflows Economic Benefits Recover > $1.5 Million/ yr of renewable energy costs Reduce biosolids disposal costs by $1.3 Million/ yr Reduce chemical costs by $400,000/ yr Hedge against rising costs of power, fuel and chemicals Payback of 15 to 20 years Community Benefits Job creation Mitigate increase of WSSC Customer Rates Reduce truck traffic

17. Wastewater Treatment Plant without Anaerobic Digestion Chesapeake Bay Restaurant Grease Primary Clarifier Secondary Reactor Secondary Clarifier FiltrationDisinfection Thickening Land Application Hauling Sludge Dewatering Centrate Raw Wastewater Pump Station Benefits & Expected Outcomes - Without Anaerobic Digestion Clogging From Grease Discharge To Sewer Increases Risk of SSOs

18. Existing Proposed Wastewater Treatment Plant Modified for Anaerobic Digestion & Combined Heat & Power Generation Chesapeake Bay Primary Clarifier Secondary Reactor Secondary Clarifier FiltrationDisinfection Thickening Land Application Hauling Biosolids Restaurant Grease Electricity to Plant Biogas (Methane) Heat CHP Side stream Nutrient Treatment (Optional) Digestion Dewatering Pump Station Raw Wastewater 40% -- 50% less Biosolids Benefits & Expected Outcomes - With Anaerobic Digestion Thickened Biosolids Digested Biosolids Centrate Removing Grease From Sewers reduces clogging Reduces SSO Potential

19. 19 Mission: T ransform our renewable biomass resources into cost-competitive, high-performance biopower Goal: Develop sustainable, cost-competitive biomass utilization technologies to: Enable the production of biofuels nationwide Reduce dependence on oil Demonstrates the commercial potential for WWTPs Nationwide to: Establish ‘blueprint’ to maximize energy recovery from biomass (Tech. transfer) Become sustainable energy producers rather than energy consumers Produce ≈750MW of Cost Effective Sustainable Energy from Biosolids & Grease Reduce national electricity demand by > 5% Reduce Biosolids Volume by 50% Reduce Nutrients to sensitive water bodies e.g. Chesapeake Bay Reduce Sanitary Sewer Overflows Reduce Greenhouse Gas Emissions Provide community benefits Relevance of this project to DOE Biomass Program Mission & Goals Win – Win - Win