Greenhouse gas emissions
We are upgrading our infrastructure and processes, and collaborating with suppliers, customers and peers to work to effectively measure, monitor and reduce emissions. In line with our goals, each of our operating companies is continuing to execute on emissions reduction strategies and also identify new opportunities to reduce emissions across scopes 1, 2 and 3.
- See About this Report for reporting boundary
- Scope 3 emissions in 2019 and 2020 for end user combustion of natural gas updated per adjustment to methodology.
- 2020 scope 1 and 2 emissions data updated following third-party verification.
- 2021 scope 1 and 2 emissions data subject to third-party verification.
- 2021 scope 2 emissions also include electricity purchased and used in the Cameron LNG facility. These emissions are not included in emissions data for prior years.
- We also track scope 3 emissions from employee travel, which comprised .002% of scope 3 emissions in 2021.
- Emissions from our natural gas power plants.
- Emissions from physical or chemical processes related to combustion.
- Percentages may not add to 100% due to rounding.
- Emissions from the generation of electricity that we lose during transmission and distribution.
Sempra’s 2021 direct (scope 1) emissions are from sources that we own or control, including stationary combustion (4.8 MMT CO2e), fugitive emissions (2 MMT CO2e) and fleet vehicles (.05 MMT CO2e).
Reducing methane emissions
Decades of work in early-adopted and innovative technologies have helped our companies identify and reduce emissions. For example, SoCalGas voluntarily began implementing and developing strong management practices to reduce its fugitive emissions as an original member of the Environmental Protection Agency’s (EPA) Natural Gas STAR program beginning in the early 1990s. Ongoing infrastructure improvements, such as eliminating high-bleed pneumatic devices and cast-iron pipes, have modernized and tightened the system.
Legislation, such as California Senate Bill 1371 “Natural Gas Leakage Abatement,” has helped formalize accountability in this area and support the efforts at Sempra California by codifying requirements for gas distribution utilities to reduce methane emissions, while prioritizing safety, reliability and affordability. According to California-based emission factors used for Senate Bill 1371 reporting in 2021, the emission rates for transmission and distribution systems ranged from 0.03 to 0.16% for SoCalGas and from 0.03 to 0.15% for SDG&E; an average between the two systems of ~0.09%. Learn more in our sustainability supplement on reducing our emissions.
SoCalGas and SDG&E are working to accelerate innovation and advancements in emissions reduction and mitigation strategies and practices. They are not only investing in new technologies, programs and procedures to detect leaks, but also technologies tied to managing our gas infrastructure more effectively.
- Advanced meters to identify leaks on the customer side
- Real-time monitoring of transmission pipelines from a state-of-the-art gas control center
- Fiber optic cables that detect methane leaks and third-party damage to pipelines in real time
- Infrared cameras to check for leaks in newly installed pipelines
- Infrared “point” sensors to detect leaks even before odorant can be detected
- In-line inspection tools, or “smart pigs”
- External corrosion surveying
- Aerial methane mapping to accelerate emissions detection and repair
Sempra is a founding sponsor of the Veritas initiative being led by the Gas Technology Institute. Veritas is a differentiated gas measurement and verification initiative intended to accelerate actions to reduce methane leakage from natural gas systems. Sempra Infrastructure and SoCalGas have been participating in the development of protocols to quantify methane emissions. Sempra Infrastructure expects to conduct a demonstration project of the Veritas initiative at its existing LNG terminals during 2022.
- Per CPUC rulemaking 15-01-008, thresholds for natural gas emissions reductions vary by classification tier, which are based on the utilities’ 2015 emissions percentages. As a class A utility, SoCalGas has specific mandated reduction targets. SDG&E is a class B utility and has a goal to reduce natural gas emissions as much as feasibly possible.
Sempra’s 2021 indirect (scope 2) emissions are from other companies’ generation of electricity that we purchased and used in our operations (0.376 MMT CO2e).
This includes electricity lost during transmission and distribution. The U.S. Energy Information Administration estimates that approximately 5% of the electricity that is delivered each year in the U.S. is lost as it passes through transmission and distribution lines. SDG&E’s estimated loss rate is 0.68% for transmission and 1.08% for distribution.
Sempra California and Sempra Texas are working to decarbonize electricity use in their owned facilities:
- By 2030, SDG&E aims to achieve zero net energy for all owned facilities (in 2020 electricity usage for owned facilities was approximately 5,596 MWh). SDG&E intends to employ energy efficiency measures and/or renewable energy generation so that its buildings consume no more than the amount of energy that can be produced onsite and through renewable sources. As an interim measure to help offset its emissions from owned facilities, SDG&E purchased renewable energy credits (RECs) in 2021.
- In September 2021, SoCalGas began purchasing 100% renewable power from the grid under Southern California Edison’s (SCE) Green Rate Program. Additionally, SoCalGas has been working with four additional electric service providers to purchase 100% renewable power for all eligible grid-connected facilities. For these facilities SoCalGas estimates that it will purchase nearly 66.5 million kilowatt hours of power from 100% renewable sources each year, which could reduce greenhouse gas emissions by over 13,000 metric tons equivalent annually.1
- In June 2020, Oncor negotiated agreements that enable it to contract for 100% renewable electricity at all Oncor facilities, and Oncor plans to continue contracting for 100% renewable electricity going forward.
- Data is an estimated emissions reduction for utility grid-connected electricity purchased under a green tariff as of January 10, 2022. Emissions reduction estimates use a location-based emission factor analysis performed in January 2022. This profile includes electricity for SoCalGas base locations, regulating stations and the Aliso Canyon compressors and facility. This profile does not include any emissions related to on-site electricity generated at operational transmission or storage facilities.
Sempra’s 2021 reported indirect (scope 3) emissions are primarily from end users’ combustion of natural gas that we delivered to them (65.3 MMT CO2e) and emissions from other companies’ generation of electricity that we delivered to end users (0.9 MMT CO2e).
Reporting on scope 3 emissions is complex, as these emissions come from a wide range of sources, some of which are difficult to measure or estimate.
Third-party verification of GHG emissions data is an important part of our process. 2020 emissions data was verified in 2021 for approximately 75% of our scope 1 and 2 emissions. Scope 3 emissions from end user combustion of natural gas, which represent 99% of our reported scope 3 emissions, are estimated. We plan to increase the scope of assurance and continue to enhance our emissions inventory in future years as part of our carbon management program.
Energy efficiency programs play a critical role in reducing emissions. Energy efficiency programs include:
- Time-of-use rates for customers;
- Peak-demand campaigns such as “reduce your use” and “dial it down”; and
- In-home efficiency programs that provide customers with more efficient appliances, weather stripping and other upgrades at no cost.
In 2021, customer energy efficiency programs at Sempra California surpassed goals and saved approximately 466 gigawatt-hours1 of electricity and more than 46 million therms1 of natural gas. These efforts avoided more than 788,700 metric tons of greenhouse gas emissions and resulted in customer savings of nearly $176 million in energy costs last year alone.
- Preliminary data, pending regulatory approval.