Tapping Landfill Gas for Campus Energy
UNH ECOLine: Tapping Landfill Gas for Campus Energy Paul Chamberlin Assistant Vice President University of New Hampshire
University of New Hampshire
Environmental Business Council Renewable Energy at Closed Landfills June 22, 2012
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
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
Combined Cycle Energy Conversion
Steam, Hot Water for heating, Steam for absorption cooling Electricity
“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
Landfill Gas The Opportunity • Naturally occurring – By-product of landfill decomposition
• Contains ~50% CH4 (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
Landfill Gas Project Concept Dirty, lowenergy gas Processing Plant (Remove Contaminates) Clean, medium energy gas
Raw Landfill Gas
Productively Use Excess
Flare Tail Gas and Unused Gas
Campus needs
UNH Co-Gen Plant Electric Generators
Turnkey Recycling and Environmental Enterprise
Closed Landfill with Gas Collection
Processing Plant Steps Raw Gas (7000 scfm design capacity) 50% Methane
Processed Gas >70% - 80% Methane
Processing Plant Steps Raw Gas
Sulfur Removal 50% Methane
Spent Iron Sponge (Solid Waste to Landfill) Processed Gas >70% - 80% Methane
Processing Plant Steps Raw Gas 50% Methane
Sulfur Removal (Sulfa-Treat)
NMOC, Siloxane Removal (TSA)
Spent Iron Sponge (Solid Waste to Landfill)
CO2 Removal
CO2 to atmosphere
(Pressure Swing Adsorbtion-PSA) Add Odorant
Processed Gas >70% - 80% Methane
Processing Plant Steps Raw Gas 50% Methane
Sulfur Removal (Sulfa-Treat)
Spent Iron Sponge (Solid Waste to Landfill)
VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA)
High Temp Flare (Destroys contaminates)
CO2 to atmosphere
Add Odorant
Processing Plant Steps Raw Gas 50% Methane
Sulfur Removal (Sulfa-Treat)
Spent Iron Sponge (Solid Waste to Landfill)
VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA)
CO2 Removal (Pressure Swing Adsorbtion-PSA)
Processed Gas 70% - 80% Methane
Thermal Oxidizer (Destroys contaminates)
CO2 to atmosphere
Processing Plant Steps
Flare Excess or Unused Gas for Odor Control
Processing Plant Steps Raw Gas
VOC, Siloxane Removal
Sulfur Removal
50% Methane
(Sulfa-Treat)
Spent Iron Sponge (Solid Waste to Landfill)
(Temperature Swing Absorbtion-TSA)
CO2 Removal
Thermal Oxidizer (Destroys contaminates)
CO2 to atmosphere
(Pressure Swing Adsorbtion-PSA)
Processed Gas Flare Excess or Unused Gas for Odor Control
>70% - 80% Methane
Add Odorant
Processed Landfill Gas to Campus
Pipeline Route
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
Wobbe Index fuel calorific v alue ( Low er Heating V alue ) WI fuel specific grav ity
Wobbe Index is stated at a reference temperature, typically 15C
Temperature Control Fuel C V 288 Tem perature C orrected WI x G as Tem p ( K ) Fuel sg Where 60ºF = 15ºC = 288ºK
As gas temperature rises above 15C, the TCWI drops. – Needed to avoid this temperature “penalty”
Added mechanical cooling to maintain gas temperature delivered to turbine at 15C
Blending
WI Rate of Change Control
Campus Use
Market Risk • Electric Wholesale Market Fluctuation • Renewable Energy Certification Market Fluctuation – $55/MW to $9/MW to $49/MW
• NG – $15/DT to $3/DT
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
Thank-You
University of New Hampshire
Environmental Business Council Renewable Energy at Closed Landfills June 22, 2012
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
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
Combined Cycle Energy Conversion
Steam, Hot Water for heating, Steam for absorption cooling Electricity
“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
Landfill Gas The Opportunity • Naturally occurring – By-product of landfill decomposition
• Contains ~50% CH4 (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
Landfill Gas Project Concept Dirty, lowenergy gas Processing Plant (Remove Contaminates) Clean, medium energy gas
Raw Landfill Gas
Productively Use Excess
Flare Tail Gas and Unused Gas
Campus needs
UNH Co-Gen Plant Electric Generators
Turnkey Recycling and Environmental Enterprise
Closed Landfill with Gas Collection
Processing Plant Steps Raw Gas (7000 scfm design capacity) 50% Methane
Processed Gas >70% - 80% Methane
Processing Plant Steps Raw Gas
Sulfur Removal 50% Methane
Spent Iron Sponge (Solid Waste to Landfill) Processed Gas >70% - 80% Methane
Processing Plant Steps Raw Gas 50% Methane
Sulfur Removal (Sulfa-Treat)
NMOC, Siloxane Removal (TSA)
Spent Iron Sponge (Solid Waste to Landfill)
CO2 Removal
CO2 to atmosphere
(Pressure Swing Adsorbtion-PSA) Add Odorant
Processed Gas >70% - 80% Methane
Processing Plant Steps Raw Gas 50% Methane
Sulfur Removal (Sulfa-Treat)
Spent Iron Sponge (Solid Waste to Landfill)
VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA)
High Temp Flare (Destroys contaminates)
CO2 to atmosphere
Add Odorant
Processing Plant Steps Raw Gas 50% Methane
Sulfur Removal (Sulfa-Treat)
Spent Iron Sponge (Solid Waste to Landfill)
VOC, Siloxane Removal (Temperature Swing Absorbtion-TSA)
CO2 Removal (Pressure Swing Adsorbtion-PSA)
Processed Gas 70% - 80% Methane
Thermal Oxidizer (Destroys contaminates)
CO2 to atmosphere
Processing Plant Steps
Flare Excess or Unused Gas for Odor Control
Processing Plant Steps Raw Gas
VOC, Siloxane Removal
Sulfur Removal
50% Methane
(Sulfa-Treat)
Spent Iron Sponge (Solid Waste to Landfill)
(Temperature Swing Absorbtion-TSA)
CO2 Removal
Thermal Oxidizer (Destroys contaminates)
CO2 to atmosphere
(Pressure Swing Adsorbtion-PSA)
Processed Gas Flare Excess or Unused Gas for Odor Control
>70% - 80% Methane
Add Odorant
Processed Landfill Gas to Campus
Pipeline Route
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
Wobbe Index fuel calorific v alue ( Low er Heating V alue ) WI fuel specific grav ity
Wobbe Index is stated at a reference temperature, typically 15C
Temperature Control Fuel C V 288 Tem perature C orrected WI x G as Tem p ( K ) Fuel sg Where 60ºF = 15ºC = 288ºK
As gas temperature rises above 15C, the TCWI drops. – Needed to avoid this temperature “penalty”
Added mechanical cooling to maintain gas temperature delivered to turbine at 15C
Blending
WI Rate of Change Control
Campus Use
Market Risk • Electric Wholesale Market Fluctuation • Renewable Energy Certification Market Fluctuation – $55/MW to $9/MW to $49/MW
• NG – $15/DT to $3/DT
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
Thank-You
