QUANTIFICATION OF METHANE SOURCE LOCATIONS AND EMISSIONS IN AN URBAN SETTING

1. QUANTIFICATION OF METHANE SOURCE LOCATIONS AND EMISSIONS IN AN URBAN SETTING B51Q Characterizing, Modeling, and Extending Urban Metabolism II Eric Crosson, Picarro

2. Quantification of Methane Source Locations and emission in an urban setting • Contributors: • NOAA – Colm Sweeney Jocelyn Turnbull • Boston University – Nathan Phillips, Lucy Hutyra • Gas Safety Inc. - Robert Ackley • Picarro – Sze Tan, Chris Rella • Purdue University - Paul Shepson, Maria Obiminda Cambaliza • NIST - James Whetstone, Tony Bova, Kuldeep R. Prasad • NASA- Richard Koyler • Penn State University – Ken Davis, Scott Richardson

3. Motivation • The identification and quantification of greenhouse gas emissions from urban centers are becoming of more interest. • Recent measurements indicate that urban emissions are a significant source of Methane (CH4) and in fact may be substantially higher than current inventory estimates. • As such urban emissions could contribute 7-15% to the global anthropogenic budget of methane*. * Wunch, D., P.O. Wennberg, G.C. Toon, G. Keppel-Aleks, and Y.G. Yavin, Emissions of Greenhouse Gases from a North American Megacity, Geophysical Research Letters, Vol. 36, L15810, doi:10.1029/2009GL)39825, 2009.

4. The Problem: Quantifying CH4 Emissions using a Network of Analyzers, Establishing priors. • For CO2- use inventories such as Vulcan as a starting point. • For CH4- no such starting point exist. GHG emissions extracted using WRF-CHEM inversion models Tall or Cell Phone Towers

5. Objectives of this effort • Develop methodologies to identify methane source locations and gather information on methane flux signals to use as priors. • Total methane emissions. • Partition methane emissions both by source and geographically within an urban center. • Develop methods that enable fast and accurate data collection and “real time” processing.

6. Taking a “snap shot”: Speed, specificity, and real-time feedback are the keys to success Oil & Gas processing auto 10 kg/min Emissions Maps Atmospheric Models Real-time Met data flight A powerful combination of new technologies is enabling scientist to generate high quality data at rates never before possible. Measurements

7. For example: Brisbane, CA (methane map) San Francisco 5 miles Brisbane Brisbane, CA

8. Speed is “everything”: Getting a “snap shot”, lot of area to cover in precious little time Bay Area: 21,442 miles of road* *Metropolitan Transportation Commission (2003) Brisbane, CA

9. Accuracy- What is the source? Uncultivated Areas Little or no wind Brackish water Petroleum Facility Brisbane, CA

10. Methane Signals Can be Confusing Storm Drains Sewer Systems Landfills Natural Gas Vehicles Natural Gas Leaks Petroleum Facilities Inefficient Vehicles

11. Specificity: isotopic carbon-13 CH4 measurements How can one help to identify the source? -37.2 per mil -45.7 per mil

12. Specificity: isotopic measurements while driving at the speed of traffic Brisbane, CA Unknown Natural gas Conc(ppm) Delta (permil) Brisbane, CA

13. Brisbane Site: looking from another angle Delta = -53.3 per mil Uncultivated Area Old Landfill Petroleum Facility Brisbane, CA

14. Methane Capture System Leaks Delta = -53.3 per mil Old Landfill Petroleum Facility Large Area Leak Brisbane, CA

15. Old landfill releasing methane in only two ways • Pipe connectors leaks. • Methane capture system is failing in one area of landfill. Take away: In a very short time, able to identify specific problems that may or may not be easily rectified by landfill owner or city fathers.

16. Quantifying Methane Source Emissions • Driving speeds of 20-30 mph • Vacaville landfill • Late evening wind conditions were very stable: • Speed 8.2 ±1.3 m/s • Direction 224.2 ± 5.0 deg wind • This was late evening with a very flat topography – estimated stability class is E or F (

17. Analyzing line integration data in real time to provide immediate feedback • Post process data using more complex models at a later time Source Location from model

18. Flux chamber measurements obtained using fast, high precision CH4 analyzers. • Using chamber measurements, one can obtain a lower limit on the total leak rate • Found leaks ranging from 40 -300 sccf/day. • As a guideline, the natural gas used in the “average” American home is 200 standard cubic ft per day. Leak Flux Leak Rate > 41 cubic ft per day 45 feet 4 feet Methane is coming out of the road.

19. Ready to tackle more complex systems?.....Methane Emissions in Indianapolis Natural Gas leak after gas station fire a few days earlier Wind direction, Day 2 Little or no emissions from waste water treatment plant Wind direction, Day 1 Emissions from these locations on landfill Unknown source of methane Methane Concentration levels are 3 times ambient 4 km from the landfill.

20. Summary • Developed fast methodologies for identifying methane source locations and gathering information on methane flux signals to use as priors. • For 2012: • Continue developing fast methodologies • Measure methane emission in several urban centers • Indianapolis • Boston • San Francisco / Bay Area • Paris