Constellation Energy : 2024 Sustainability Data Index & Factsheet

2024 Constellation Sustainability Report Sustainability Data Index & Factsheet

Sustainability Data Index & Factsheet

Constellation's 2024 Sustainability Data Index & Factsheet discloses our performance and relevant policies for key sustainability topics. Metrics reflect company-wide data and are reported based on calendar year, unless otherwise indicated. Additional context is provided in our 2024 Sustainability Reportand Reporting Frameworks Content Index.

Please Note: The abbreviation "N/A" refers to metrics that are not applicable to Constellation, while the abbreviation "N/R" refers to 2022 metrics that were not reported in last year's Sustainability Report.

KEY LINKS

Constellation Code of Business Conduct

Constellation Supplier Code of Conduct

Constellation 2022 Form 10-k

Constellation 2023 Proxy Statement

Constellation 2024 Sustainability Report

The Constellation 2024 Sustainability Report details our strategies, goals and initiatives to address key sustainability issues across our entire operations and value chain. Unless otherwise noted, this report reflects our performance and progress for the period of January 1, 2023, to December 31, 2023.

Reporting Frameworks Content Index

Our Reporting Frameworks Content Index outlines how our existing disclosures align with the 2021 GRI Standards and the recommended metrics for the SASB Electric Utilities and Power Generators Standard.

External GHG Emissions Inventory Assurance Statement

Our External GHG Emissions Inventory Assurance Statement Provides verification of our Scope 1, 2 and 3 GHG emissions.

SUSTAINABILITY REPORT 2024

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General

Financial Performance

Unit

2022

2023

GRI/SASB Indicator

Additional Information

Operating revenues	Million USD	$24,440	$24,918
Net revenues	Million USD	$495	$1,610

GRI 201-1

Market Information

Unit

2022

2023

GRI/SASB Indicator

Additional Information

Total customers served (annual average)	Number	1,732,657	1,984,408
Residential	Number	1,177,006	1,392,245
Commercial	Number	546,133	583,352
Industrial	Number	9,518	8,811

SASB IF-EU-000.A

Customer counts are for power customers only.

Energy Generation, Capacity, and Sales

Unit

2022

2023

GRI/SASB Indicator

Additional Information

Total electricity generated	GWh	198,949	200,785
Nuclear	GWh	173,350	174,047
Share of Constellation generation	Percent	87%	87%
Natural gas and oil	GWh	21,563	22,959
Share of Constellation generation	Percent	11%	11%
Renewables and storage	GWh	4,036	3,779
Share of Constellation generation	Percent	2%	2%
Share of Constellation electricity generated in	Percent	3.1%	2.2%
regulated markets

SASB IF-EU-000.D

Please refer to the Sales and Supply Sources section in Constellation's 2023 Form10-Kfor additional details on 2023 and 2022 data.

This data index shows net generation gigawatt hours (GWh) calculated based on Constellation's ownership level of generation assets according to the equity share boundary approach, as defined by the GHG Protocol. The generation table in Constellation's 2023 Form10-Kshows our ownership of consolidated generating facilities at 100% to be consistent with the income statement presentation.

SUSTAINABILITY REPORT 2024

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Energy Generation, Capacity, and Sales

Unit

2022

2023

GRI/SASB Indicator

Additional Information

Total owned generating capacity	MW	32,355	33,094
Nuclear	MW	20,895	22,070		Increase in capacity due to acquisition of ownership stake in South Texas Project Electric Generating
					Station (STP).
Share of total Constellation owned generating	Percent	65%	67%
capacity
Nuclear fleet capacity factor	Percent	94.8%	94.4%		Capacity factor refers to the ratio of electrical energy produced by our nuclear generating fleet for a
					period of time compared to the electrical energy that could have been produced at continuous full
					power operation during the same period.
					Data reflects the capacity factor for nuclear facilities operated by Constellation.
Natural gas and oil	MW	8,807	8,461
Share of total Constellation owned generating	Percent	27%	25%
capacity
Renewables and storage	MW	2,653	2,563		Decrease in reported net capacity in 2023 reflects implementation of the Resource Adequacy Planning
					Effective Load Carrying Capability (ELCC) program in the PJM region, which reserves a percentage of
Share of total Constellation owned generating	Percent	8%	8%		the nameplate capacity of our hydroelectric units.
capacity
Total electricity delivered to customers	MW	201,914,320	197,989,177	SASB IF-EU-000.B
Residential customers	MWh	12,110,749	11,797,826
Commercial customers	MWh	103,830,270	104,493,054
Industrial customers	MWh	19,200,571	18,802,190
All other retail customers	MWh	544,522	434,298
Wholesale customers	MWh	66,228,208	62,461,809
Wholesale electricity purchased for customers	TWh	70.7	67.2	SASB IF-EU-000.E
Natural gas purchased for customers	MMBtu	1,131,174,557	1,173,405,651

SUSTAINABILITY REPORT 2024

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Climate and Environmental Management

GRI/SASB Indicator

Board level responsibility for climate and	The Constellation Board of Directors provides oversight on the development and execution of our corporate citizenship strategy, including	GRI 2-9
environmental issues	sustainability and environmental stewardship. The Corporate Governance Committee of the Board reviews our environmental strategies, including	GRI 2-12
	climate and sustainability policies. This oversight includes issues such as water, biodiversity, air emissions and operational waste. The Nuclear
	Oversight Committee oversees the safe and reliable management and operation of our nuclear generating facilities and reviews environmental, health	GRI 2-13
	and safety issues relating to nuclear generating facilities, including the safe management of spent nuclear fuel. For more information, please see our
	2024 Proxy Statement,relevant committee chartersand2024 Sustainability Report.
Executive level responsibility for climate and	The Constellation Sustainability Council is overseen by the Vice President of Sustainability and Climate Strategy and consists of a cross-functional	GRI 2-9
environmental issues	group of executive leaders from key departments across Constellation. The Council meets four times per year to review sustainability policies and
	initiatives, ensure strategic alignment, discuss emerging ESG trends and make informed suggestions to management.
	Additionally, our executive team, including our CEO and other senior management, is accountable for our environmental compliance and assurance
	strategy. At Constellation, we are committed to protecting and sustaining the environment by complying with applicable regulatory requirements while
	protecting and enhancing the air, water and land. Constellation's Environmental Council oversees our program and is composed of leaders from each
	business unit. The Council is subject to oversight from the Board of Directors and meets four times per year to review policies and initiatives, ensure
	strategic alignment, discuss emerging environmental trends and make informed suggestions to senior executive leadership.
	For more information, please see our 2024 Sustainability Report.
Relevant policies and resources	Corporate Governance Committee Charter
	Nuclear Oversight Committee Charter
	Climate Change Policy
	Environmental Policy
	Water Resource Management Policy
	Biodiversity Policy
	Environmental Justice Policy
	Environmental Stewardship & Impact webpage
	Nuclear EMS Certification Statement

SUSTAINABILITY REPORT 2024

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Energy/Fuel Consumption

Unit

2022

2023

GRI/SASB Indicator

Additional Information

Total energy/fuel consumed	GWh	48,098	51,727	GRI 302-1	Per CDP guidance, this data excludes nuclear fuel.
					2022 data throughout the Climate section of this Data Index may differ from previously disclosed
Total non-renewable energy/fuel	GWh	47,144	50,768
	amounts due to re-baselining, as discussed in more detail below in the Greenhouse Gas Emissions
					section of this Data Index.
Total renewable energy/fuel	GWh	43	43
Total purchased electricity	GWh	911	916
Percentage of energy consumed from the grid	Percent	1.9%	1.8%
Energy consumption intensity	GWh / million USD	1.97	2.08	GRI 302-3
	revenue
Customer Energy Savings	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Reductions in energy requirements of sold products	MWh	571,307	511,306	GRI 302-5	This data only includes energy savings realized through customer energy efficiency projects
and services achieved during the reporting period				SASB IF-EU-420a.3	implemented byConstellation Energy Solutions.

SUSTAINABILITY REPORT 2024

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Greenhouse Gas Emissions	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Scope 1 GHG emissions	Metric tons CO2e	9,102,084	9,679,181	GRI 305-1	Gases included in the calculation include CO2, CH4, N2O, HFCs, PFCs and SF6. Constellation calculates
				SASB IF-EU-110a.1	Gases included in the calculation include CO2, CH4, N2O, HFCs, PFCs and SF6. Constellation calculates
				Scope 1 emissions using guidance from the IPCC 4th Assessment Report.
					The increase to our Scope 1 emissions in 2023 is the result of our natural gas generation assets in
					Texas being called on more frequently and for longer durations than in prior years to ensure the reliable
					delivery of power to meet the demand of that state's electricity grid
					Per GHG Protocol guidance, the GHG "inventory boundary must be held consistent between those data
					sets that are used for a direct comparison over time." Following this, we have conducted a re-baselining
					of our GHG inventory to ensure comparison of "like with like" emissions boundaries and calculation
					methodologies over time. Re-baselining was triggered after exceeding our 5% re-baselining threshold
					due to (1) changes in our organizational structure due to acquisition and divestment, (2) improvements
					to our GHG accounting methodology for better alignment to GHG Protocol guidance, and (3) updated,
					more accurate source data from which our GHG emissions are calculated. As such, our 2022 GHG
					emissions have been updated to reflect these changes and may vary slightly from what was previously
					reported.
Scope 1 biogenic CO2 emissions	Metric tons CO2e	12	13	GRI 305-1	This represents CO2 emissions from the combustion or biodegradation of biomass.
Percentage of Scope 1 emissions covered under	Percent	8.5%	6.4%	SASB IF-EU-110a.1
emissions-limiting regulations
Percentage of Scope 1 emissions covered under	Percent	99.4%	99.4%
emissions-reporting regulations

SUSTAINABILITY REPORT 2024

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Greenhouse Gas Emissions	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Scope 2 (location-based) GHG emissions	Metric tons CO2e	298,226	292,891	GRI 305-2	Gases included in the calculation include CO2, CH4, N2O, HFCs, PFCs, SF6 and NF3, but only CO2, CH4 and
					N2O are relevant to our operations. Constellation calculates Scope 2 emissions using guidance from the
					IPCC 4th Assessment Report.
Scope 2 (market-based) GHG emissions	Metric tons CO2e	362,974	379,850	GRI 305-2	Our Scope 2 market-based emissions are higher compared to our Scope 2 location-based emissions
					due to the use of residual mix emission factors, in line with GHG Protocol Scope 2 guidance Table 6.3
					Market-based Scope 2 data hierarchy examples. Voluntary and compliance purchases of clean energy
					are removed from the energy mix (the denominator for residual mix emission factor) to more accurately
					reflect emissions associated with a buyer's purchases and avoid double counting of clean energy
					attributes.
					Historically, we have taken an annual energy matching approach to reducing our market-based Scope
					2 emissions by retiring emission-free energy certificates (EFECs) from nuclear generation to cover 100
					percent of our annual grid-supplied electric use in the PJM market territory, as was the practice prior to
					our separation from Exelon in 2022. As part of our climate roadmap work in 2023, we reassessed our
					approach to using contractual instruments like EFECs to reduce our market-based Scope 2 inventory.
					We determined we needed a change to align our clean energy procurement strategy with what we
					believe is required for firm, reliable grid decarbonization: hourly carbon-free energy matching of load
					with supply within geographically deliverable boundaries. As part of this pivot, we re-baselined our
					historic market-based Scope 2 inventories and are using this year to reset, without any procurement
					of contractual instruments against our 2023 inventory, while we turn our ambitions toward making
					progress on hourly matching against our own electricity use in our 2024 market-based Scope 2
					inventory and beyond.
					Had we continued the historic practice of retiring EFECs to cover 100 percent of our annual grid-
					supplied electric use in the PJM market territory, our Scope 2 market-based emissions would have
					increased by 13.4 percent in 2023 compared to 2022, from approximately 46,000 to 53,000 metric tons
					of CO2e.
Total Scope 1 and 2 (location-based) GHG emissions	Metric tons CO2e	9,400,309	9,972,072
Total Scope 1 and 2 (market-based) GHG emissons	Metric tons CO2e	9,465,058	10,059,031
GHG emissions intensity (Scope 1 and 2,	Metric tons CO2e /	385	400	GRI 305-4
location-based)	million USD revenue
GHG emissions intensity (Scope 1 and 2,	Metric tons CO2e /	387	404
market-based)	million USD revenue

SUSTAINABILITY REPORT 2024

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Greenhouse Gas Emissions	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Total relevant Scope 3 GHG emissions	Metric tons CO2e	81,398,873	87,482,855	GRI 305-3	Gases included in the calculation include CO2, CH4, N2O, HFCs, PFCs and SF6. Constellation calculates
					Scope 3 emissions using guidance from the IPCC 4th Assessment Report. There are 17 potential Scope
					3 categories. Constellation currently tracks and reports those most pertinent to our business and where
					we can most effectively take action today. Additional information on Scope 3 accounting can be found at
					http://ghgprotocol.org/scope-3-technical-calculation-guidance.
Category 3 Fuel- and Energy-related:Long-term	Metric tons CO2e	21,050,841	24,922,161		Includes owned and Power Purchase Agreement (PPA) renewables for which attributes may have been
and spot market power purchases for resale -- fossil					sold as RECs or retired for Renewable Portfolio Standards (RPS) obligations.
Category 11 Use of Sold Products: Natural gas	Metric tons CO2e	60,079,112	62,322,096
sold by Constellation New Energy (as used by
customers)
Category 11 Use of Sold Products: Heating and	Metric tons CO2e	259,284	226,578
cooling equipment operated for others
Category 6 Business travel	Metric tons CO2e	3,261	5,817
Category 8 Upstream Leased Activities: Fuel and	Metric tons CO2e	6,376	6,203
energy used in leased facilities and equipment
GHG Emissions Reductions/Avoidance	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Total avoided carbon emissions from carbon-free	Metric tons CO2e	124,235,613	124,553,213		Estimated based on 178 TWhs of zero-emissions electricity generated by our nuclear and renewable
generation assets					fleet during 2023, using the U.S. Environmental Protection Agency's (EPA) GHG Equivalencies
					Calculator.
Avoided carbon emissions - nuclear generation	Metric tons CO2e	121,099,805	121,587,152
Avoided carbon emissions - renewable generation	Metric tons CO2e	3,135,807	2,966,061
GHG emissions reduced as a direct result of	Metric tons CO2e	243,749	227,898	GRI 305-5	This data only includes GHG emissions avoided as a result of customer energy efficiency projects
reduction initiatives					implemented byConstellation Energy Solutions.

SUSTAINABILITY REPORT 2024

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Other Significant Air Emissions	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Nitrogen oxide (NOx) emissions	Metric tons	938	804	GRI 305-7	In 2023, our measured emissions intensity rates, on a per MWh
				SASB IF-EU-120a.1	generated basis, for NOx and SOx were well below the U.S. electric generation industry average, and we
NOx emissions intensity	kg/MWh generated	0.005	0.004
	have lowered our NOx and SOx emission rates each by 46 and 71 percent, respectively since 2019. For
Sulfur oxide (SOx) emissions	Metric tons	118	53		more information, please see the most recent Benchmarking Air Emissions Report, published November
	2023.
SOx emissions intensity	kg/MWh generated	0.0006	0.0003
Particulate matter (PM), lead (Pb), mercury (Hg),	Metric tons	N/A	N/A
volatile organic compounds (VOCs), persistent organic
pollutants (POP) and hazardous air pollutants (HAP)
emissions
Ozone-depleting substances (ODS) emissions	Metric tons of CFC-11	3.76	1.59	GRI 305-6
	equivalent

Environmental Compliance	Unit	2022	2023	GRI/SASB Indicator	Additional Information
Percentage of generation operations covered under an	Percent	100%	100%		Refer to Constellation 2024 Sustainability Report: Managing Environmental Programs section for
environmental management system (EMS)					additional details.
Total permit non-compliances	Number	12	16	GRI 2-27
Air	Number	6	4
Land	Number	0	1
Water	Number	6	11	SASB IF-EU-140a.2
Total notice of violations	Number	0	0	GRI 2-27
				SASB IF-EU-140a.2
Air	Number	0	0
Land	Number	0	0
Water	Number	0	0
Total monetary value of significant fines	Million USD	0	0	GRI 2-27
Total reportable spills	Number	0	2		Only spills that exceed federal reportable quantities for ground or water are disclosed here.

SUSTAINABILITY REPORT 2024

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Water		Unit	2022	2023	GRI/SASB Indicator		Additional Information
Total water withdrawal/intake		Megaliters	46,682,483	48,697,737	GRI 303-3
					SASB IF-EU-140a.1
Share of withdrawn water returned to source	Percent	98.5%	98.5%
Total water discharge		Megaliters	45,974,591	47,960,046	GRI 303-4
Total water consumption		Megaliters	707,892	737,692	GRI 303-5
					SASB IF-EU-140a.1
Total water consumed in areas with water stress	Megaliters	Negligible	Negligible		We use the World Resources Institute Aqueducttool to broaden our understanding of potential future
							water scarcity risks caused by climate change and economic growth and how our operations may be
							impacted or may pose impacts in these scenarios. Constellation's largest water-consuming sites are in
							low-medium-risk regions, while our operations in high-water-risk areas use negligible amounts of water
							and do not face water scarcity risks.
Total water recycled through closed cycle cooling	Megaliters	7,003,852	6,649,680
systems
Biodiversity		Unit	2022	2023	GRI/SASB Indicator		Additional Information
Site biodiversity programs certified	by the Wildlife	Number	14	15	GRI 304-3		For more information on our WHC-certified programs, please visit WHC's websiteand select
Habitat Council (WHC)							"Constellation" from the "Company/Organization" drop-down menu.
Site biodiversity programs certified	by the National	Number	14	14
Wildlife Federation (NWF)
Waste		Unit	2022	2023	GRI/SASB Indicator		Additional Information
Total hazardous waste generated		Metric tons			GRI 306-3		2022 values have been revised from those previously reported in last year's report, which included
	26	42
							universal waste, a specially-regulated subset of hazardous waste that includes batteries, mercury-
Hazardous waste diverted from disposal	Metric tons	<1	1	GRI 306-4
	containing lamp bulbs, etc., as defined by U.S. EPA regulations. The updated values reported in this
							year's report exclude universal waste.
Total radioactive waste disposed		Cubic meters	1,393	1,849			For additional context on how we safely manage nuclear waste, please see the Managing Our Waste
							Responsibly section of our 2024 Sustainability Report.

SUSTAINABILITY REPORT 2024

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