This document discusses an innovative laser-based solution for natural gas leak detection. It introduces the MobileGuard system, a vehicle-mounted methane and ethane analyzer that uses tunable diode laser absorption spectroscopy (TDLAS) for mobile monitoring of gas distribution pipelines. The system can detect leaks from 150 meters away and map their locations. It is also introduced the μPortable analyzer for on-foot investigations of leak locations identified by MobileGuard. Both tools use off-axis integrated cavity output spectroscopy (OA-ICOS) which provides highly sensitive, selective, and calibration-free measurements. The system represents a significant improvement over traditional walk-based surveying and can survey areas more quickly and efficiently.

1. Novel laser analyzers for measurements and
mapping of natural gas leaks while driving
AEIT 2016 – Capri, October 6th, 2016
B. Leen, J. Savee, M. Gupta, A. Gardner, D. Baer and N. Bonavita

2. Agenda
 Leak Detection in Gas Distribution
 Rationale
 Traditional Solutions
 Innovative laser analyzer-based integrated solution
 MobileGuard
 µPortable Analyzer
 OA-ICOS: The Enabling Technology
 Tunable Diode Laser Absorption Spectroscopy (TDLAS)
 Off-Axis ICOS
 Advantages over other analytical technologies
 Conclusions
Month DD, YYYY

3. Natural Gas Distribution
October 24, 20163
Background
• Natural gas is a vital component of world energy supply, ~ 25% of U.S. energy
• First widespread U.S. distribution system in 1836
(City of Philadelphia)
• Today > 200 U.S. distributors, > 300k miles of pipeline
• Cast Iron (early 20th century)
• Steel (introduced in 1950s, bulk of existing pipeline)
• Plastic (last 30 years)
• Aging infrastructure – leaks create significant safety and environmental hazard
• 2010: San Bruno, CA (PG&E) – 8 dead, 38 injured, 40 homes destroyed
• 2014: New York, NY (Con Ed) – 8 dead
• Regulation by Department of Transportation Pipeline & Hazardous Materials Safety
Administration
• Survey once or more per year in business districts and populated areas; less
frequent for remote areas
• Growing pressure for environmentally-focused regulation

4. Traditional Methods for Leak Detection
October 24, 20164
Parts per million
• Natural gas is typically > 90% methane,
remainder is primarily larger hydrocarbons
• Most utilized tools based on very old
technology (flame ionization) – sensitive to
methane in the parts per million range
• Current leak survey methods are slow and
laborious:
• Operators must walk along mains/service
lines
• Must be within 2-3 meters from the leak
• Measurement time ~ 5 seconds
• Many sources of naturally occurring methane
• Process is paper based and operator
dependent
Representative
Composition of Natural
Gas
Methane (95%)
Ethane (3.2%)
Propane (0.2%)
iso-Butane
(0.03%)

5. Next Generation Mobile Monitoring
System Requirements
1Lamb, Brian K., et al. "Development of atmospheric tracer methods to measure methane emissions from natural gas facilities and urban areas.“
Environmental science & technology 29.6 (1995): 1468-1479.
 Vehicle-mounted sensors have a long history and have been extensively vetted
 Allows for cost-effective surveys of large areas at a rapid pace
 Requires:
 Manufacturable, easy-to-use gas sensors that do not require researchers
 Complete sensor suite - sensor, GPS, anemometer, gas inlet…
 Data aggregation, analysis and interpretation - leak detection software
 Data presentation - HMI

6. Agenda
 Leak Detection in Gas Distribution
 Rationale
 Traditional Solutions
 Innovative laser analyzer-based integrated solution
 MobileGuard
 µPortable Analyzer
 OA-ICOS: The Enabling Technology
 Tunable Diode Laser Absorption Spectroscopy (TDLAS)
 Off-Axis ICOS
 Advantages over other analytical technologies
 Conclusions
Month DD, YYYY

7. Natural Gas Distribution
An Innovative, Integrated Solution
 Los Gatos Research
 Founded in 1994, acquired by ABB
in October 2013
 Located in Silicon Valley (San Jose,
California)
 More than 50 employees, including
14 Ph.D. scientists
 Pioneer and world leader in laser-
based gas sensing
 Over 14 patents granted with >100
scientific papers/articles published
in peer-review journals
 Serves industrial, environmental,
military, and medical markets
 An innovative, integrated solution has
been developed by Los Gatos Research
 Innovative: based on latest
generation laser spectroscopy
 Integrated: it combines modern
technologies to efficiently measure,
identify and report gas leaks in
urban areas
 Two stage approach:
I. MobileGuardTM for wide areas
coverage
ΙΙ. µPortable Analyzer for in-depth
local identification
Month DD, YYYY

8. Natural Gas Leak Detection System (I)
October 24, 20168
MobileGuardTM Overview
Methane/Ethane Analyzer Anemometer
(wind speed + direction)
GPS
Real-time data analysis
• Mobile deployment → significant reduction in survey time
• MobileGuard system offers powerful real-time leak surveying
tool
• Discriminate against non-natural gas sources of methane
• Estimated leak locations
• Automated leak cataloging and reporting
• Customers: Atmos Energy, Sempra Energy, Enbridge Gas, …
MobileGuard
Graphically displays leak route, survey area and leak indications

9. Parts-per-billion (ppb) sensitivity
© ABB Group
October 24, 2016 | Slide 9
Natural Gas Leak Detection System (I)
Ultra-sensitive Mobile Monitoring
Geo-located mobile measurements
Sharable digital maps with estimated leak locations
Detect up to 150 m away
Survey quickly and efficiently
Easy to interface with existing GIS

10. Graphically displays leak route, survey area and leak indications
© ABB Group
October 24, 2016 | Slide 10
Natural Gas Leak Detection System (I)
Map Display
Survey Area
Survey Route
(Breadcrumbs)
Leak Indication
(unknown source)
Leak Indication
(thermogenic)

11. © ABB Group
October 24, 2016 | Slide 11
Natural Gas Leak Detection System (I)
Measured Data and Automated Alarms
Leak Indications List
Real-time Status
CH4 History

12. © ABB Group
October 24, 2016 | Slide 12
Natural Gas Leak Detection System (I)
Automated System Alarms
System Errors CH4 Alarm
System health notifications:
No warnings
High methane detected (> 2.6 ppm, settable)
Audible alarm

13. Natural Gas Leak Detection System (I)
Example: Drive with 3 Leak Locations

14. Natural Gas Leak Detection System (I)
Example: Expanded View of Leak Locations
 3 distinct methane leak locations
 Simplified leak detection algorithm
 Use ethane measurements to identify
natural gas leaks

15. Natural Gas Leak Detection System (I)
Why Measure Ethane?
0,06
4,65
1,4
6
3,2
3,36
3,4
8,61
8,32
5,44
7,07
7,67
0
0
Ethane Fraction [%]
• Ethane is a fingerprint of natural gas leakage not found in biogas
• Methane isotopes are not unique and ratios may change with soil migration
• In ethane-poor regions, system can operate in methane-only mode

16. Natural Gas Leak Detection System (I)
Why Measure Ethane?
 Controlled release of pure methane, 4% ethane/methane, and 9% ethane/methane
 Analyzer can readily detect ethane and quantify ethane/methane fraction

17. Natural Gas Leak Detection System (I)
Why Measure Ethane?
 Preliminary demonstration at PG&E training facility in Livermore, California
 Ethane vs. methane slope = 3.2%, matches PG&E natural gas composition

18. Natural Gas Leak Detection System (I)
Methane/Ethane Analyzer for Mobile Monitoring
© ABB Group
October 24, 2016 | Slide 18
Improvements:
 19” Rack Compatible
 4U High
 12 VDC
 Integrated Pump
 Integrated GPS Receiver
 Water Trap
 Humidity Sensor
 Proprietary, 3D Printed
Inlet

19. Natural Gas Leak Detection System (I)
Methane/Ethane Analyzer for Mobile Monitoring
© ABB Group
October 24, 2016 | Slide 19
Water Trap
ICOS Engine
Integrated Pump
Data Acquisition
& Analysis

20. Natural Gas Leak Detection System (II)
µPortable Analyzer Overview
© ABB Group
10/24/2016 | Slide 20
 CH4 sensitivity: single-digit ppb
 Fast data rate: 5 Hz
 Wireless user interface: Tablet or smartphone
 13 lbs / 5.8 kg (with battery)
 4 hour battery life
 0-50º C operating temperature

21. Natural Gas Leak Detection System (II)
Revolutionizing Walking Surveys of NG Leak Detection
October 24, 2016
21
Current Technologies
- ppm-level sensitivity
- 30-45 min to find a
leak
- Needs to be 2-3
meters from the leak
- Labor intensive
- Consumable required
µPortable
- ppb-level sensitivity
- 5-10 min to find a leak
with the MobileGuard
- Can be far from the leak
- Reduces labor cost
- No consumables

22. Step 5:
Compliance/Records
© ABB Group
October 24, 2016 | Slide 22
MobileGuard + µPortable Analyzer
Integrated Detection, Pinpointing and Data Archiving
Step 2:
Triage/Dispatch
Utility Command Center
Leak Investigator
Step 3:
Investigation
Leak #1
Leak #2
…
Step 4:
Investigation Report
Walking path w/CH4
Leak GPS location
Leak Grade
Survey Notes/PicturesMobileGuard
Step 1:
Mobile Survey

23. Methane/Ethane Analyzer
MobileGuardTM Performances
© ABB Group
10/24/2016 | Slide 23
Feature Specification Advantage
Highly Sensitive Methane: 2 ppb
Ethane: 10 ppb
Observe and attribute small leaks
from large distances
Fast Response Response time of up to 5 Hz Allows for driving speeds in excess
of 40 mph
Highly Selective No interferences from ambient
compounds or higher hydrocarbons
No false positives
Calibration-Free Utilizes Off-Axis ICOS – a first principles
measurement technique
No need to calibrate the analyzer
Large Dynamic Range Methane: 1 – 100,000 ppm
Ethane: 0 – 100 ppm
Accurately quantify leaks
independent of distance and size
Fast Warm-Up Time Less than 2 minutes from power on to
data collection
Improves uptime and efficiency
Low Power Analyzer and pump only require 180 W Can power from a standard car
battery power point
Wide temperature range Operates from -5 to +50 °C Can be deployed in a wide array of
environments

24. Agenda
 Leak Detection in Gas Distribution
 Rationale
 Traditional Solutions
 Innovative laser analyzer-based integrated solution
 MobileGuard
 µPortable Analyzer
 OA-ICOS: The Enabling Technology
 Tunable Diode Laser Absorption Spectroscopy (TDLAS)
 Off-Axis ICOS
 Advantages over other analytical technologies
 Conclusions
Month DD, YYYY

25. The Enabling Technology
Tunable Diode Laser Absorption Spectroscopy
Beer-Lambert-Bouguer Law: ∆I/Io = 1-exp(-αLeff)
∆I/Io = fractional change in laser intensity
α(λ) = absorption coefficient
Leff = effective optical path length
 TDLAS provides a direct measurement of gas concentration → little or no calibration
 Provides highly specific and very fast measurements with no consumables
 Open-path methods are non-intrusive: Ideal for monitoring in hostile conditions
 ABB uses conventional TDLAS for cross-stack measurements of O2, NH3, HCl, …
 May not provide sufficient sensitivity for all applications (e.g. H2S in natural gas, etc.)
Month DD, YYYY

26. The Enabling Technology
Off-Axis Integrated Cavity Output Spectroscopy (ICOS)
Detector
Lens
HR mirrors (R~0.9999)
Diode Laser
Gas Inlet Gas Outlet
(to vacuum pump)
T P
Data collection
and analysis system
laser control
electronics
 Small portion of laser power transmits through the front mirror
 Optical cavity provides an effective pathlength of 1 – 10 kilometers
 Allows for detection of very low concentrations → ppb-level sensitivity
 Very robust - exact alignment, gas pressure, and gas temperature are not critical
 Mirrors can be cleaned in the field by minimally-trained personnel in < 20 minutes
 Economical to manufacture without extensive infrastructure
 Off-Axis ICOS works at any wavelength from the UV through the mid-IR
 Couple multiple lasers into a single cavity for multi-species detection
Cavity mirrors easily serviced, if necessary.
Month DD, YYYY

27. The Enabling Technology
Off-Axis ICOS: Measured Data
 Measure baseline, absorption, ringdown, detector offset, T and P every sweep
 Operate at low pressure to narrow lineshapes and improve selectivity
 Scan laser at 100–1000 Hz to provide complete measurement every 1–10 ms
 User-selectable data rate allows for averaging to improve precision
Month DD, YYYY

28. The Enabling Technology
Off-Axis ICOS: Calculated Results
 Fit measured absorption to Voigt function(s)
 Area under peak is a direct measurement of gas concentration
 For many applications, analyzer does not require calibration
 Spectra provides verification of observed phenomenon
Month DD, YYYY

29. The Enabling Technology
Advantages of Off-Axis ICOS
Feature Advantage Benefit
1st principles measurement
technology
Accurate,
Calibration-Free
Accurate to better than 1% without
calibration and only infrequent verification.
Provides very long optical
pathlength (> 1000 m)
High Sensitivity Detect contaminants at ppb-levels
Scan laser at 100 – 1000 Hz Fast T90-10 times < 15 seconds allows for
process control and real-time monitoring
High-resolution diode laser
absorption technology
Highly Selective No cross-interferences between measured
compounds or background matrices
Effective optical pathlength
decreases with absorption
Large Linear Dynamic Range Can accurately quantify both trace and
percent levels for measurements during
routine operation and excursion events
Sample is directly measured by
without conditioning
No Consumables Reduces cost of ownership associated
with maintenance and consumables
Analyzer can be remotely
accessed
Remote Operation and
Diagnostics
Further reduces cost of ownership due to
maintenance
Measured spectra includes
baseline
No Zero Drift No need to calibrate and correct for zero
drift
Month DD, YYYY

30. Agenda
 Leak Detection in Gas Distribution
 Rationale
 Traditional Solutions
 Innovative laser analyzer-based integrated solution
 MobileGuard
 µPortable Analyzer
 OA-ICOS: The Enabling Technology
 Tunable Diode Laser Absorption Spectroscopy (TDLAS)
 Off-Axis ICOS
 Advantages over other analytical technologies
 Conclusions
Month DD, YYYY

31. Conclusions
MobileGuardTM First Applications
 Launched in Q1-2016 MobileGuard is already in use at several
North America locations, for customers including:
 Atmos Energy
 Sempra Energy
 Enbridge Gas
 Google
 Environmental Defence Fund
 A first European application is in progress in UK
Month DD, YYYY

32. Conclusions
MobileGuardTM: Advantages
© ABB Group
10/24/2016 | Slide 32
• Safety: Find dangerous leaks faster by surveying with ppb sensitivity while
driving
• Labor Efficiency: Mains and services surveyed quickly while driving (up to
40 mph!)
• Ease of Use: System powers on and is ready to use in less than 5 minutes
• Reduced false positives: MobileGuard measured methane and ethane
which allows differentiation of pipeline from naturally occurring gas (e.g.,
landfill, sewer, etc.)
• Reduce Greenhouse Gas Emissions: Methane has 20X the warming
effect compared to CO2
• Reduction of Lost Product: 1 – 6% of product is lost
• Digital Reports: Electronic data simplifies compliance reporting and
implementation of a fully digital survey process

33. Conclusions
µPortable: Opening Doors to ...
October 24, 201633
µPortable
Miniaturization & Cost Reduction
Environment &
Research
Going Further
Other Leak
Detections
NH3, HF, etc.
Low Cost
Platform
Competitive with Existing
Technologies

34. Conclusion
New opportunities for improved process monitoring
OA-ICOS product line offers the ability to improve processes,
increase product quality and save money.
1. Lowest cost of ownership
2. Highest overall performance (sensitivity/accuracy/precision)
3. Widest measurement range
4. Simplest to use and service
Month DD, YYYY