Air Quality / Non-GHG Emissions

We’re proud to say that since 2005, we have reduced our direct emissions of nitrogen oxides (NO_x) by around 70% and sulfur dioxide (SO₂) by around 99%. We achieved large reductions in NO_x emissions by adding natural gas capability to several generating units at our steam plants. We also make use of emissions-reducing controls such as low NO_x burners. Increasing the proportion of cleaner-burning natural gas used to produce steam was a key factor in these emission reduction efforts. Our steam stations comply with New York State NO_x limits, and stations monitor NO_x targets throughout the year to meet these limits. We have also drastically reduced our SO₂ emissions by using predominantly natural gas and low-sulfur fuels. Over sixty percent of CECONY’s annual steam production comes from co-generation, which reuses waste heat from boilers or gas turbines to produce additional energy. This efficient use of waste heat, in addition to advanced pollution controls on some of CECONY’s units, also helps to reduce the per-unit non-GHG emissions such as NO_x.

While we predominantly use natural gas for steam and electricity production (over 99% of the fuel used in our steam and electric generating units in 2023 was natural gas), we retain backup fuel sources to maintain reliability during periods of natural gas-system limitations. No. 4 oil and kerosene are the backup fuels currently used at most of our steam and electric generating stations. CECONY began the use of No. 2 oil at two of its steam generating stations towards the end of 2023, and by the end of 2024, all generating units that use No. 4 oil will be fully transitioned to No. 2 oil. No. 2 oil is lighterthan No. 4 oil and has a lower concentration of criteria pollutants. Use of No. 2 oil also aligns with a New York City mandate aimed at reducing local air pollution by requiring steam and electric generating facilities to cease the use of No. 4 oil in boilers by January 1, 2025.

Since 2005, we have reduced our emissions of NO_x by 70% and SO₂ by 99%

Over its 141 years of operation, the fuels upon which the CECONY steam system relies have continued to evolve, from using coal as a fuel source, to heavy fuel oils, to natural gas. One of our most prominent challenges in the coming decades will be adapting our steam system for its next evolution to become a significant contributor to the decarbonized clean energy future. What alternative fuels and technologies will come next, and how will we incorporate them into our steam system? Our engineers are working on it. We’re looking forward to keeping our community and stakeholders abreast of our progress toward a net-zero-emissions future.

Similar to GHG emissions, non-GHG emissions are expected to continue to follow a downward trend, as described in the decarbonization plan included in our Steam Long Range Plan and latest Steam Rate Case filing. As we decarbonize our steam system, we will look to transform our energy supply through the use of various technologies and are currently exploring the use of low-carbon fuels; industrial heat pumps; electrification of boilers with clean energy; thermal storage; carbon capture and sequestration; and/or carbon offsets; among other potential methods. We will also enable a fundamental change in energy consumption by supporting energy efficiency.

The Company’s Clean Energy Commitment: Pillar 4 Aim for Net-Zero direct greenhouse gas emissions (Scope 1) by 2040 for electric co-generation from our steam system will drive steam energy efficiency programs, alternative fuels, and technology innovation opportunities we are exploring to reduce overall emissions.

In addition, as these programs and activities are implemented, we anticipate a moderate reduction in annual steam sales, which will correlate to decreased fossil fuel usage and will result in reduced emissions overall. This modest decline in sales can be contributed to electrification, customer energy efficiency, and the impact of climate change.

Over 60% of CECONY's annual steam production comes from co-generation, which reuses waste heat.

Non-GHG Emissions Nitrogen Oxides (NO_x) & Sulfur Dioxide (SO₂) (thousands of metric tons)

• NO_x
• SO₂

DIRECT EMISSIONS (thousand metric tons)

	NOₓ	SO₂
2023	1.27	0.03
2022	1.31	0.13
2021	1.16	0.03
2020	1.00	0.02
2019	1.23	0.09
2018	1.37	0.20
2017	1.16	0.11
2016	1.24	0.13
2015	1.49	0.32
2014	1.65	0.33
2013	1.90	0.54
2012	1.79	0.56
2011	2.17	0.93
2010	2.47	1.28
2009	2.49	1.53
2008	2.31	1.41
2007	2.79	1.92
2006	2.27	1.73
2005	3.33	2.63

GHG Emissions Reductions

In 2019, New York State enacted the Climate Leadership and Community Protection Act (CLCPA) that established a goal that 70 percent of the electricity procured by load serving entities regulated by the New York State Public Service Commission come from renewables by 2030. Further, the CLCPA requires the statewide electrical demand system to have zero emissions by 2040. In addition, the law established a Climate Action Council to recommend measures to attain the law’s greenhouse gas (GHG) limits, including measures to reduce emissions by displacing fossil-fuel fired electricity with renewable electricity or by implementing energy efficiency measures to achieve an 85% reduction of GHG emissions by 2050 from 1990 levels. In support of the State’s goals, Con Edison (the Company) is committed to serving an essential role in delivering the transition to a clean energy future, through our Clean Energy Commitment. We are committed to building a resilient electric grid that is capable of delivering 100% clean energy by 2040. We are aiming for net-zero Scope 1 emissions for electric co-generation from our steam system by 2040, working to decarbonizing our steam system and other company operations, and planning to reduce our fugitive methane emissions from our natural gas delivery system by 85% by 2040.

Our Energy Vision is to serve an essential role in the delivery of a clean energy future for our customers. We will do that by investing in, building, and operating reliable, resilient, and innovative energy infrastructure, advancing electrification of heating and transportation, and transitioning away from fossil fuels to a net-zero economy by 2050. To achieve our vision, we are committed to reducing our carbon footprint. We firmly support efforts by local, state, and federal agencies to reduce GHG emissions. We have reduced our carbon emissions by 55% (43.2 million metric tons of CO2 equivalent) since 2005 – equal to taking more than 500,000 vehicles off the road.

Since 2005, we have reduced our CO₂ by 55% – that is equal to taking over 500,000 vehicles off the road.

Greenhouse Gas Assessment

In 2023, as a part of our commitment to transparent and accurate GHG inventory reporting, we engaged with an internationally recognized sustainability consultant to thoroughly evaluate our current GHG inventorying processes and methodologies. The objective was to determine whether our GHG emissions calculations and reporting:

• align with industry best practices, and national and international standards such as the GHG Reporting Protocol
• can support third-party verification.

Scope 3

The GHG assessment identified additional potential Scope 3 categories for reporting moving forward: purchased goods and services, capital goods, upstream transportation and distribution, waste generated in operations, business travel, employee commuting, and investments. In 2024, we will further assess this gap, using screening calculations to inform material Scope 3 categories for subsequent GHG inventories.

Third-Party Verification

In 2024, we anticipate building a GHG inventory baseline for the year 2019 that will be evaluated by an independent third-party organization for alignment with the GHG Reporting Protocol and serve as a potential framework for annual GHG inventories moving forward.

Con Edison recognizes the international standard for delineating emission sources into various categories of “scope” based on whether the company was directly responsible or indirectly responsible for the GHG emissions. These categories are broken into 3 scopes of emissions:

2023 Con Edison, Inc. Direct GHG Emissions - Scope 1

• CECONY Gas Usage for HVACon
• CECONY Compressor & Heater Stationson
• O&R CH₄on
• CEI Fleeton
• CECONY Substationon
• CECONY CH₄on
• CECONY Steam & CoGenon

Scope 1 emissions are those GHGs emitted into the atmosphere by Company-owned or-controlled assets. As with our non-GHG emissions, the majority of Con Edison’s Scope 1 emissions (87%) result from CECONY’s operation of steam, electric, and co-generation plants, where fossil fuel is combusted, and GHGs are emitted as a result. Additionally, fugitive Scope 1 emissions occur when pressurized equipment and infrastructure containing GHGs has a controlled or uncontrolled emission into the atmosphere. Fugitive Scope 1 emissions are principally composed of SF₆ from electric distribution equipment (2%), and methane (CH₄) from the Company’s natural gas distribution system (8% CECONY; 1% Orange & Rockland). The Company’s vehicle fleet is also a source, albeit relatively small (1%) for Scope 1 emissions.

Con Edison, Inc. Direct and Indirect GHG Emissions - Scope 1, 2, and 3

• Scope 1: CECONY Steam / Electricon
• Scope 2: T&D Losses and Company Used Electricon
• Scope 3: Gas Deliverieson
• Scope 3: Electric Deliverieson

The chart above presents the proportion of our Scope 1, 2 and 3 emissions, focusing on the Scope 3 emissions from the delivery to and use of electricity and gas by our customers (not including emissions associated with our supply chain or methane emissions “upstream” from the production and delivery of natural gas to the “city gate”).

• Our Scope 1 emissions comprised largely of steam, electric, and co-generation plant operations, which together make up 7% of our total GHG emissions,
• Scope 2 emissions are associated with T&D losses and comprise 2%,
• The majority (91%) of our total GHG emissions are Scope 3, nearly evenly split between the emissions associated with generating the electricity (44%) and customer combustion of natural gas (47%) that we deliver.

Con Edison, Inc. Direct GHG Emissions - Scope 1 (thousand metric tons CO₂e)

8,000

6,000

4,000

2,000

2007

1,163

999

392

3,419

2008

1,777

615

385

3,196

2009

2,177

416

376

3,004

2010

2,051

247

373

3,302

2011

2,592

184

368

2,829

2012

2,666

179

346

2,782

2013

2,611

171

293

2,898

2014

2,769

164

283

2,757

2015

2,789

132

276

2,776

2016

2,880

107

267

2,719

2017

2,958

83

259

2,673

2018

2,905

75

250

2,743

2019

3,066

83

239

2,585

2020

3,232

65

230

2,446

2021

3,187

60

216

2,510

2022

3,158

61

207

2,547

2023

3,297

48

230

2,398

• Avoided Emissions Compared to 2005 Baseline
• SF₆ Emissions
• Methane Emissions
• CO₂ Emissions

This chart above presents Con Edison Inc. Scope 1 GHG emissions trend data from 2011 through 2023. They show a trending increase in avoided GHG emissions compared to a 2005 baseline, including significant reductions in SF₆ and methane. Carbon dioxide emissions, which are largely from the steam, electric, and co-generation plant operations have been reduced over this time by switching to natural gas as a fuel source. Planning for future decarbonization efforts to drive further GHG reductions in these plants is underway and we look forward to sharing our findings. 

CON EDISON, INC. DIRECT GHG EMISSIONS - SCOPE 2 (million metric tons CO₂e)

4

3

2

1

2009

1.42

2010

1.37

2011

1.51

2012

1.11

2013

1.19

2014

1.09

2015

1.32

2016

1.32

2017

1.35

2018

1.24

2019

1.16

2020

0.92

2021

1.30

2022

1.02

2023

0.62

• CO₂ Emissions

Scope 2 emissions are indirect GHG emissions from the generation of purchased electricity consumed by the Company. The consumption of electrical power at Company facilities necessitates, in part, that an upstream power generator combusts fossil fuels to generate electricity, which, in turn, leads to greenhouse gas emissions. For Con Edison, nearly all Scope 2 emissions originate as electric consumption by Company-owned assets, and losses in electric distribution and transmission (T&D losses).

CON EDISON, INC. DIRECT GHG EMISSIONS - SCOPE 3 (million metric tons CO₂e)

60

45

30

15

2014

40.90

2015

41.80

2016

41.10

2017

33.90

2018

35

2019

32.50

2020

29.50

2021

31.40

2022

32.40

2023

32.40

• CO₂ Emissions

Scope 3 emissions represent indirect GHG emissions from sources not owned or controlled by the Company, which include, among other things, indirect emissions generated as a result of customers using Con Edison’s services. The vast majority of Con Edison’s Scope 3 emissions indirectly relate to the delivery of electricity and gas to our customers, which results in GHG emissions from either the upstream generators supplying the electricity, or the Company’s customers’ combustion of gas. Another, and more difficult to calculate component of Con Edison’s Scope 3 emissions include the emissions resulting from the Company’s supply chain; specifically, those emissions resulting from the production of material, transportation, and labor associated with Company suppliers. 

Steam Environmental Efforts

We provide customers with U.S. Food and Drug Administration quality steam, of which over 60% was co-generated in 2023. Because the steam is co-generated, customers can apply for points toward Leadership in Energy and Environmental Design (LEED) certification of their buildings and increase their score in Energy Star’s portfolio manager. Our co-generated steam reduces carbon emissions by approximately 25% of what would have been otherwise emitted through traditional boilers—that is equal to removing approximately 200,000 vehicles from the road every year.

Our customers also benefit from the advantages of a centralized district steam system, which reduces onsite emissions from boilers in customer buildings. These centralized investments benefit all customer buildings. The district system’s ability to aggregate a wide variety of customer load profiles also allows for a higher average efficiency than what can be achieved at a single location. All these benefits are reflected in the most recent NYC Local Law 97, in which our district steam system was identified as the lowest greenhouse gas emitting energy source per unit of energy delivered.

We are taking a more forward-thinking approach, conducting research, and evaluating opportunities for more efficient generation and customer programs, while using existing and emerging technologies. To continue supporting our customers in a changing environment, Steam Operations has been proactive in several efforts, such as benchmarking with district steam systems in other cities that are using their district energy networks to achieve their carbon reduction goals. We have also been an active member in discussions and studies as regulations for the city and state plans evolve.

Steam Operations established an internal cross-functional team, dedicated to evaluating the feasibility of carbon- reduction technologies and strategies with the existing steam system. These include alternative fuel sources, carbon capture, production via electric boilers and industrial heat pumps using available renewable energy, expanding and/or converting to hot water systems, wasted heat recovery sources, and other emission reduction technologies such as thermal energy storage. Moreover, the Company has partnered with the National Renewable Energy Laboratory (NREL) to investigate a large-scale geothermal project at our East River campus.

As part of the approved Steam Rate Case 22-S-0659, the Company received preliminary funding to begin developing two decarbonization demonstration projects and to conduct two critical studies that will pave the way towards the Clean Energy Future.

Decarbonization demonstration projects:

• An industrial heat pump project at our East River Station – this technology will use heat from the East River, as well as adjacent waste heat sources, to inject thermal energy into our steam system. Once online, it is expected to be one of the largest heat pumps in the world!
• A district hot water loop project – this extension to our system would use waste energy from an existing steam customer and provide thermal energy to neighboring buildings, to help the buildings eliminate their use of fossil fuels. This district energy system strategy is currently being used in various systems in Europe and can be adapted for use in our steam system.

Decarbonization studies:

• Customer Electrification Challenges – A team of consultants was hired to visit ten buildings in our steam service territory, and prepare a comparative engineering and cost analysis for each to convert to electric service. The results of this study will identify any the complexities that buildings may face when converting from their existing onsite boiler-based systems. Moreover, detailed cost analyses will be performed for each to determine the overall cost impacts and economic options for each building. Results will be used for energy efficiency incentive creation as well as clean energy marketing efforts.
• Steam Decarbonization Study – A team of consultants was hired to build on the existing Clean Energy Future planning work done by Con Edison to date. This study will evaluate each generation location, all applicable decarbonization technologies, as well as the future energy need forecasts to determine a year-over-year phasing plan for all generation assets. This team will help establish the future roadmap our business will use to reduce the carbon intensity of our system and continue to improve our Local Law 97 coefficient on behalf of our customers.

Moving into the future, we are expecting to build and launch a portfolio of additional demonstration projects for the technologies that seem most promising for carbon-free steam generation. We will work closely with key stakeholders and customers so that our steam system remains a viable and clean energy option for our existing and new customers.

Reduction of SF₆ Emissions

In accordance with a 1999 memorandum of understanding between the U.S. Environmental Protection Agency (EPA) and CECONY, we agreed to reduce our emissions of SF₆ gas (sulfur hexafluoride) by 5% annually from our 1996 baseline. In 2023, we released about 98% less SF₆ than in 1996, well ahead of our commitment to the EPA. SF₆ is a nontoxic, nonflammable greenhouse gas, with a warming potential more than 22,000 times higher than carbon dioxide. SF₆ can remain in the atmosphere for up to 3,200 years. It is also a highly efficient insulating medium and arc extinguisher used throughout the electric industry in different types of equipment, including high-voltage breakers and gas-insulated switchgear. 

In 2023, we released about 98.72% less SF₆ than in 1996, well ahead of our commitment to the EPA.

Research is underway, particularly in Europe, to find equally efficient alternative gases, but Con Edison has not yet identified substitutes that would replace the SF₆ in existing high voltage equipment. Con Edison is a member of the Electric Power Research Institute (EPRI) where we benchmark with peer utilities and stay informed of industry updates. EPRI is supporting research to identify alternative gases as well. Some utilities in the United States have replaced SF₆-containing equipment, but those programs have been limited to lower voltage classes of equipment than those used in CECONY’s electric system. Therefore, at the present time, limiting emissions is the best strategy for contributing to a healthier environment and helping to reduce global warming.

While we have greatly reduced our emissions in the past decades, we continue to cut our remaining emissions. We established a five-year plan at the start of 2020 to reduce SF₆ emissions by 500 pounds annually. This is a rate of more than 5% annually from current levels. So far, we have achieved 5% annual reductions in 2020, 2021, 2022 and 2023.

To reduce SF₆ emissions, we use programs developed by a dedicated team that established a process to address leaking equipment in a timely matter. For example, a team of specially trained technicians constantly monitors the emissions of all equipment to enable quick and efficient detection and repair of SF₆-containing equipment. The team also uses cameras designed to detect SF₆ to monitor equipment. We follow best management practices for handling SF₆ gas with minimal emissions, including using innovative leak-sealing techniques to make the necessary repairs. We also have several targeted programs to retire or replace older SF6 equipment with new SF₆-containing equipment, including circuit breakers, automatic ground switches and gas-insulated switchgear. New SF₆-containing equipment used in replacements typically has a much lower leakage rate than earlier technologies.

CECONY SF₆ Leakage Rate History % Nameplate Capacity

• SF₆ Emission Rate

Note: The above chart shows the leakage rate (pounds of SF₆ leaked divided by the nameplate capacity of the system), which is based on the percentage of the total amount of SF₆ gas in the electric equipment (nameplate capacity) of our electric system.  The data is presented this way so that our performance can be compared to other electric systems that might be larger or smaller. 

Natural Gas Leaks

CECONY performs gas leakage surveys more frequently than prescribed by federal and New York State regulations. Our accelerated survey effort is supported by an aggressive leak repair program that also repairs leaks much sooner than the timeframes required by New York State regulations (Code). The leak repair program addresses Type 1 leaks, which are an immediate hazard and thus repair work has to commence as soon as a leak is discovered to eliminate the hazard, Type 2A and Type 2 leaks, which are not an immediate hazard and thus repair work can be scheduled and completed in a prescribed timeframe, and Type 3 leaks, which are non-hazardous; the Code does not require that Type 3 leaks be repaired at all. The table below highlights the beneficial environmental impact (avoided emissions) of CECONY adopting a more comprehensive leak identification and repair program with shorter repair intervals for leak repair (based on actual average repair timeframes) compared to Code requirements.

This proactive leak identification and rapid repair program significantly reduces the amount of natural gas emissions that would have occurred had CECONY simply adhered to Code repair requirements. The program reduced annual emissions from leaks by approximately 123 million cubic feet, or about an 89% reduction compared to the emissions that would occur under the New York State-mandated timelines. (This estimation is conservative because it assumes Type 3 leaks have a 12-month repair cycle when in fact, the Code does not require Type 3 leaks to be repaired at all.) CECONY has estimated the emissions using emission rates determined by a study of CECONY’s gas distribution system undertaken by the Environmental Defense Fund (EDF) and performed by Colorado State University, a nationally recognized leader in the field of emission detection and quantification.

To enhance the effectiveness of our overall leak identification process, CECONY is investigating new advanced leak detection technologies, and pursuing an enhanced leak identification process through collaborative research. Moreover, CECONY sought and gained approval for funding high emissions gas leakage surveys using advanced leak detection technologies to survey at least one-third of its distribution system each calendar year.

CECONY is also using cross-compression technology to capture natural gas during main replacement activities. The captured gas is transferred to other portions of the piping system so that the gas is not emitted into the atmosphere. Although the use of this technology is currently limited to the higher-pressure portions of the distribution system, CECONY is committed to expanding its use going forward. We are also evaluating the benefit of smaller compressor unit for applications not suitable for the full-size unit currently in use. O&R used the same technology for its main replacement program in 2023.

CECONY’s and O&R leak management initiatives have also incorporated the benefits of smart meter installations. Natural gas detectors that use the smart meter network to alert us of natural gas leaks are being installed on every gas service in the system. These detectors are being installed near piping points of entry where the gas service enters the building. CECONY and O&R worked with a gas-detector manufacturer to innovate these first-of-its-kind gas detectors. By the end of 2023, more than 223,000 detectors had been installed and 3,400 leaks had been detected and repaired in CECONY’s service territory— potentially preventing dangerous incidents and reducing emissions. These state-of-the-art devices can detect natural gas at levels as low as 10 percent of the lower explosive limit. Additionally, O&R is in the middle of a three-year program and on track to install approximately 15,400 natural gas detectors by the end of 2024. As of the end of 2023, O&R installed 8,713 units. Not only do these detectors sound an alarm at customer locations, they also automatically alert CECONY’s and O&R’s Gas Emergency Response Center, prompting a rapid safety response as well as the quick mitigation of any associated methane emissions.

Additionally, O&R performs annual leak surveys of its distribution system that exceed code requirements to detect methane emissions and make associated repairs to the gas system. O&R is evaluating several initiatives to meet the requirement under New York’s Climate Leadership and Community Protection Act of having net-zero carbon emissions economy-wide in New York State by 2050. We are also exploring new tools and technologies that would aid in mitigating emissions during normal operations and continue to conduct field trials of enhanced leak detection tools.

Methane Challenge

In 2016, CECONY joined forty other gas local distribution companies as a founding partner in the EPA’s Natural Gas STAR Methane Challenge. The goal of this program is to encourage companies to commit publicly to reducing methane emissions by replacing a substantial number of natural gas mains.

Our goal is to replace 4% of our cast iron and unprotected steel mains each year. Since 2017, we have replaced 629 miles of such mains, which included a 5% replacement rate for 2023. The replacement of mains made from cast iron and unprotected steel with mains made from plastic leads to methane emission reductions. As of 2023, we have reduced our gas system methane emissions by 57% from the 1990 baseline.

Likewise, O&R has significantly reduced methane emissions for over 20 years. O&R has had an aggressive gas main replacement program since 1998, replacing over 472 miles of leak prone pipe in that time. O&R’s low pressure/ cast iron gas system was completely retired in 2018, eliminating a significant source of methane emissions. As an indication of the success of this main replacement program, O&R went from a year-end leak backlog of over 650 gas leaks in 2012 to a zero-gas leak backlog at year-end 2023. At current replacement rates, O&R expects to retire our remaining bare steel pipe and Aldyl plastic pipe (an older type of plastic pipe) by approximately 2030.

In 2016, Orange and Rockland Utilities, Inc. (O&R) entered into the Methane Challenge. O&R committed to replacing cast iron and unprotected steel main and services with plastic at an annual rate of 6.5%. To date, on average, O&R has replaced targeted mains and services at an annual rate of 6.85%. O&R continues to report under this voluntary program for data keeping and tracking purposes.

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