Preliminary measurements from the natural gas system in

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Preliminary measurements from the natural gas system in California: from well to downstream of

Preliminary measurements from the natural gas system in California: from well to downstream of the meters June 1 st, 2015 Marc L. Fischer ([email protected] gov) • Motivation and Overview – NG methane contribution as a CA climate pollutant – Bottom-up estimates of natural gas (NG) methane emissions • CALGEM-NG – – Regional Top-down Study of SF Bay Area Methane Airborne Facility Scale Measurements Localized Mobile Plume Integration (MPI) Emissions from Residential Buildings 1

Team Acknowledgements LBNL: Seongeun Jeong, Toby Walpert This work was supported by the California

Team Acknowledgements LBNL: Seongeun Jeong, Toby Walpert This work was supported by the California Energy Commission, Natural Gas Environmental Research Program UC Davis: Stephen Conley, Ian Faloona UCI: Tianyang Zhu, Don Blake SJSU: Matt Llyod, Neil Larau, Craig Clements Picarrro: Eric Crosson, Chris Rella BAAQMD: David Fairley, Phil Martien, Saffet Tanrikulu CEC: Guido Franco, Simone Brant PG&E: François Rongere, Gerry Bong UC Berkeley: Allen Goldstein, Abhinav Guha NOAA-CCG: Arlyn Andrews , Laura Bianco, Ed Dlugokencky, Jim Wilczak, Steve Montzka, Ben Miller, Pieter Tans CIT: Sally Newman, Debra Wunch, Paul Wennberg UCR: Jingsong Zhang, Mixtli Campos NASA Ames: Laura Iraci, Emma Yates, Matt Johnson JPL: Riley Duren, Christian Frankenberg, Charles Miller UCSD: Ray F. Weiss, Ralph Keeling, Peter Salameh Earth. Networks: Christopher D. Sloop, Bob Marshall CARB: Ying-Kuang Hsu, Abhilash Vijayan, Jorn Herner, Bart Croes, 2 Fischer, Jim Vernon Hughes, Marc Vayssières, Richard Bode, Joseph Narady, and Webster Tassat, Mac Mc. Dougall, Ken Stroud

Problem Overview • Natural gas provides 43% California’s fossil fuel energy • Methane is

Problem Overview • Natural gas provides 43% California’s fossil fuel energy • Methane is a potent short lived climate pollutant – A 3% well-to-burner methane leak approximately equals climate forcing from remaining 97% gas combusted to CO 2 on 20 year timescale – Pre-meter distribution and post-meter consumption leakage paths deserve attention • CA and US now moving to control CH 4 emissions – Current inventories typically lower than measurements in facility or regional studies – Likely ~ 10% California’s methane emissions from NG • CEC survey project provides new look across CA natural gas infrastructure 3

Overview of Natural Gas System • Many sub-sectors may contribute to total NG emissions

Overview of Natural Gas System • Many sub-sectors may contribute to total NG emissions • Post-meter emissions previously neglected • More complete representation captures emissions per energy delivered Courtesy G. Franco and S. Ziaja adapted from US-EPA 4

Bottom-up Natural Gas Inventories Vary • Combine US-EPA emission factors and GIS activity data

Bottom-up Natural Gas Inventories Vary • Combine US-EPA emission factors and GIS activity data § Production: Conventional and enhanced recovery wells § Transmission, compression, and storage § Distribution 0. 3% of regional consumption (1 st guess) § Prior CALGEM-NG emissions (Jeong et al. , 2014) still lower in So. CAB than recent top-down (Peischl et al. , 2013) CALGEM-NG Methane Flux (nmol m-2 s-1) § Resulting CALGEM-NG emissions likely 200 -400 Gg CH 4 yr-1 § Livestock and landfills likely much larger in CA so NG 10 -20% of total CA CH 4 5

CALGEM-NG CH 4 Collaboration • Regional Emissions – Tower Collaborations • Facilities Leakage –

CALGEM-NG CH 4 Collaboration • Regional Emissions – Tower Collaborations • Facilities Leakage – Aircraft Observations • Localized Plumes – Mobile Plume Integration – Building Studies 0. 1 °× 0. 1 ° LBL & Picarro Plume UCD Airborne UCI VOC SJSU Lidar LBL Residential 6

Estimating Regional NG Emissions • NG: Total CH 4 emission ratio only large in

Estimating Regional NG Emissions • NG: Total CH 4 emission ratio only large in urban/production areas 0. 1 °× 0. 1 ° • Evaluate emissions in SF Bay Area • Light alkane composition (ethane: methane) key for attribution Total NG Methane NG CH 4 Total CH 4 nmol/m 2/s NG: Total Ratio nmol/m 2/s San Joaquin Valley So. CAB 0. 1 °× 0. 1 ° 7 Regions

Napa 450 Fremont 400 San Jose 350 San Rafael Pittsburg 300 Vallejo 250 Richmond

Napa 450 Fremont 400 San Jose 350 San Rafael Pittsburg 300 Vallejo 250 Richmond 200 Concord 150 Redwood City 100 Santa Rosa 50 Livermore 0 2 09 -1 7 20 05 -0 20 04 20 20 02 - 20 01 8 99 - 19 96 -9 5 19 93 -9 19 1 San Francisco 89 -9 19 • Collaboration with BAAQMD (Fairley et al. , 2014, ES&T) • Estimate CH 4 emissions CH 4: CO correlations + CO emission inventory CH 4 emissions (Gg. CH 4/year) Bay Area Methane 500 – Total CH 4 1. 5 – 2. 0 x BAAQMD Inventory – AQ focused sites likely biased toward CO emissions – Likely NG significant urban contribution • Future: include VOC tracers to quantify NG emissions from distribution 8 Inventory ch 4*

Airborne Studies of Point Sources Validated with Controlled Release Tests Methane Plume Controlled PG&E

Airborne Studies of Point Sources Validated with Controlled Release Tests Methane Plume Controlled PG&E methane and ethane release in natural gas § Release rate ~ 15 kg CH 4 hr-1 § Flight data estimates recover both Wind methane and ethane to within 20% § Recover ethane: methane ratio to better than 10% Wind * note 0. 1 Gg CH 4 yr-1 = 11. 4 kg CH 4 hr-1 Courtesy Steven Conley

Bay Area NG Storage and Petroleum Refining § Bottom-up estimates for average storage emissions

Bay Area NG Storage and Petroleum Refining § Bottom-up estimates for average storage emissions 80 kg CH 4 hr-1 (US - EPA) § Airborne measurements at four storage facilities (June, 2014 – May, 2015) § Two sites non-detection, one site small ~ 11 Kg CH 4 hr-1 § Five flight days at 4 th site larger and variable 80 - 300 kg CH 4 hr-1 § C 2 H 6: CH 4 matches PG&E ( ~ 5% vol) § Initial measurements at three refineries (Feb-May, 2015) § Large variation in emissions 30 - 250 kg CH 4 hr-1 § and ethane: methane ratios 6 -20% 10

San Joaquin Valley Production § Flights April -June, 2014 § Clear downwind enhancements of

San Joaquin Valley Production § Flights April -June, 2014 § Clear downwind enhancements of CH 4 and ethane on both days § Emissions from example production field § Flight data 14 +/- 5 Gg CH 4 yr-1 § CALGEM bottom-up 10 Gg CH 4 yr 1 § Another larger field shows episodic emissions, apparently correlated with well completion 11

Local Measurements: LBNL Mobile Plume Integration (MPI*) System Gas System CH Plume at 1,

Local Measurements: LBNL Mobile Plume Integration (MPI*) System Gas System CH Plume at 1, 2, 4 m agl 4 • Cross-wind integral of CH 4 enhancement flux quantifies plume emissions 4 m 2 m 1 m – Sample inlets can be set to 4 -8 m above ground – Anemometry of wind velocity • Recent system developments – Tests at LBNL and PG&E facilities – Better than 30% accuracy with 3 passes in most conditions – Multi-analyzer system w/ 13 CH 4 allows NG attribution for strong plumes Wind direction * Patent Pending 12

Capped Gas Wells in Sacramento Delta • Plan drive using CA Dept. Cons. well

Capped Gas Wells in Sacramento Delta • Plan drive using CA Dept. Cons. well map data • 1 day drive-by of 12 capped wells MPI System – Quantify one plume 130 +/- 40 sccm (5 passes) Methane Plume – Detected 3 plumes 40 -350 sccm (one pass each) – Non-detect for 2 sites – 7 sites not downwind of public road CH 4 Enhancement in vertical plane Capped well 13

Bakersfield Distribution System § Survey 80 km of Bakersfield public streets § Detect 20

Bakersfield Distribution System § Survey 80 km of Bakersfield public streets § Detect 20 large leaks above elevated varying background § 40% emissions found within 0. 5 km of large distribution pipes § Plume integrations yield total emissions of 6. 4 kg CH 4 hr-1 § Scaling by area suggests total emissions ~ 90 kg CH 4 hr-1 § Comparing with consumption suggests ~ 0. 3% distribution leakage § Consistent with CALGEM-NG distribution estimate CH 4 enhancements (green), distribution (orange) and transmission (blue) pipelines 14

Residential Leakage § Measurements § Depressurize house producing controlled inflow of outdoor air §

Residential Leakage § Measurements § Depressurize house producing controlled inflow of outdoor air § Measure CH 4 enhancement relative to outdoor air § 13 CH /12 CH used to identify gas vs. 4 4 biological methane § Results from 10 SF Bay homes § Average leak rate 7 +/- 2 sccm equal ~ 0. 16% of consumption § Indoor CH 4 enhancements show NG 13 CH signature 4 § New CEC project underway to measure 50 -75 homes across CA housing stock Outdoor CH 4 C 0 Air flow in Q Q Ci Ci E leak C 0 Q + E = C i Q E = Q (Ci - C 0) Measured indoor (white) and outdo (grey) methane during calibrated indoor leak (red) 15

Combustion Appliance Leakage § Methods § Mass balance gathering total exhaust stream as with

Combustion Appliance Leakage § Methods § Mass balance gathering total exhaust stream as with building level test § Ratio of CH 4: CO 2 enhancements + fuel use yields emissions § Examples: tank-less water heaters, clothes driers, gas range § Three tank-less water heaters emitted 80 - 300 sccm CH 4 § 1 hr operation ~ equal 1 day of quiescent house leakage § Two clothes driers emitted ~ 10 sccm emissions in continuous operation § One gas range emitted ~ 5 sccm in continuous operation 16

Summary and Next Steps § Work sponsored by CEC identifying key components of natural

Summary and Next Steps § Work sponsored by CEC identifying key components of natural gas CH 4 emissions from CA § Emissions from production and distribution sectors uncertain and likely underestimated in state current inventories § Production emissions episodic -> continuous observation § Distribution emissions diffuse -> NG tracers § Atmospheric measurements can quantify emissions reductions at multiple scales § Need to identify critical gaps in mitigation activities § Energy systems, agriculture, waste management 17