UNH ECOLine: Tapping Landfill Gas for Campus Energy Paul Chamberlin

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1 UNH ECOLine: Tapping Landfill Gas for Campus Energy Paul Chamberlin Assistant Vice President University of New Hampshire

2 University of New Hampshire Environmental Business Council Renewable Energy at Closed Landfills June 22, 2012

3 The University of New Hampshire 12,000 Undergraduates 3000 graduate students 5.7 million square feet Flagship campus of the University System of New Hampshire

4 UNH Energy Initiatives 2001 DOE Recognition UNH among top 5% of peer institutions for energy efficiency 2004 UNH Utility Infrastructure Project Approved $28 million investment in modern technology Combined Heat and Power (Co-Gen) plant Avoided significant investment in old technology boilers Produce electricity as well as heat for campus Enabled switch to cleaner burning natural gas as primary fuel vs. #6 oil used in old boilers Substantially reduced purchase of electricity Siemens SGT300 DLE 7.9MW turbine generator selected

5 Combined Cycle Energy Conversion Steam, Hot Water for heating, Steam for absorption cooling Electricity

6 By reducing the university s dependence on fossil fuels and reducing our greenhouse gas emissions, EcoLine is an environmentally and fiscally responsible initiative. UNH is proud to lead the nation and our peer institutions in this landmark step toward sustainability. -- UNH President Mark W. Huddleston

7 Naturally occurring Landfill Gas The Opportunity By-product of landfill decomposition Contains ~50% CH 4 (methane) Commercial natural gas is >96% methane Must be captured to control landfill odor System of wells, piping and pumps already exists to collect gas Turnkey Landfill (TLF) in Rochester producing more gas than Waste Management can use Gas can be used as fuel to generate electricity WM Limited by emission permit and PSNH system capacity

8 Landfill Gas Project Concept Dirty, lowenergy gas Raw Landfill Gas Productively Use Excess Processing Plant (Remove Contaminates) Clean, medium energy gas Campus needs Flare Tail Gas and Unused Gas Electric Generators UNH Co-Gen Plant

9 Turnkey Recycling and Environmental Enterprise

10 Closed Landfill with Gas Collection

11 Raw Gas (7000 scfm design capacity) Processing Plant Steps 50% Methane Processed Gas >70% - 80% Methane

12 Processing Plant Steps Raw Gas 50% Methane Sulfur Removal Spent Iron Sponge (Solid Waste to Landfill) Processed Gas >70% - 80% Methane

13 Processing Plant Steps Raw Gas 50% Methane Sulfur Removal (Sulfa-Treat) NMOC, Siloxane Removal (TSA) Spent Iron Sponge (Solid Waste to Landfill) CO2 Removal (Pressure Swing Adsorbtion-PSA) Processed Gas >70% - 80% Methane Add Odorant CO2 to atmosphere

14 Raw Gas 50% Methane Processing Plant Steps Sulfur Removal (Sulfa-Treat) VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA) High Temp Flare (Destroys contaminates) Spent Iron Sponge (Solid Waste to Landfill) CO2 to atmosphere Add Odorant

15 Processing Plant Steps Raw Gas 50% Methane Sulfur Removal (Sulfa-Treat) VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA) Thermal Oxidizer (Destroys contaminates) Spent Iron Sponge (Solid Waste to Landfill) CO2 Removal (Pressure Swing Adsorbtion-PSA) CO2 to atmosphere Processed Gas 70% - 80% Methane

16 Flare Excess or Unused Gas for Odor Control Processing Plant Steps

17 Processing Plant Steps Raw Gas 50% Methane Sulfur Removal (Sulfa-Treat) VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA) Thermal Oxidizer (Destroys contaminates) Spent Iron Sponge (Solid Waste to Landfill) CO2 Removal (Pressure Swing Adsorbtion-PSA) CO2 to atmosphere Flare Excess or Unused Gas for Odor Control Add Odorant Processed Gas >70% - 80% Methane Processed Landfill Gas to Campus

18 Pipeline Route

19 Fuel Management Assuring Quality and Quantity Existing Siemens SGT300 DLE turbine Original design for natural gas Wobbe Index 44.7 MJ/nM3 Siemens Modified Turbine for lower BTU fuel Minimum Wobbe Index = 32 MJ/nM3 Equivalent of ~77% CH4 Wobbe Index Rate of Change < 4%/minute Anticipated PLG could go as low as WI=28 Needed to maximize PLG use

20 Wobbe Index WI fuel calorific v alue ( Low er Heating fuel specific grav ity Value) Wobbe Index is stated at a reference temperature, typically 15 C

21 Temperature Control Tem perature C orrected WI Fuel CV Fuel sg x G as 288 Tem p ( K ) Where 60ºF = 15ºC = 288ºK As gas temperature rises above 15 C, the TCWI drops. Needed to avoid this temperature penalty Added mechanical cooling to maintain gas temperature delivered to turbine at 15 C

22 Blending

23 WI Rate of Change Control

24 Campus Use

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26 Market Risk Electric Wholesale Market Fluctuation Renewable Energy Certification Market Fluctuation NG $55/MW to $9/MW to $49/MW $15/DT to $3/DT

27 Using Landfill Gas Major Considerations Single vs. Dual Cycle Generation Engine Selection Gas Quality O2 levels critical (>4% unsafe) Moisture Sulfur ppm Siloxanes CH4% Wobbe Index & Fuel Quality Stability Gas Quantity Transportation Market Risk

28 Thank-You