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Connecticut   Connecticut Profile

State Profile and Energy Estimates

Profile AnalysisPrint State Energy Profile
(overview, data, & analysis)

Last Updated: June 15, 2017

Overview

Connecticut is located in the southwestern corner of New England on hilly terrain between New York's Hudson River Valley and Rhode Island's Narragansett Bay.1 The state does not have any fossil fuel reserves, but it does have renewable resources.2,3 The largest river in the state, the Connecticut River, flows south, forming a broad valley that runs through the center of the state.4 That river and other Connecticut rivers provide the state with a renewable resource that has been used since colonial times, and the rivers could provide more hydroelectric power in the future.5,6 In southern Connecticut, the hills give way to the coastal lowlands along the Long Island Sound. Winds that flow across the state's northwestern highlands and sweep along the shoreline of the Sound give the state a moderate wind energy resource.7,8 Connecticut is the third smallest state in land area, but it is the fourth most densely populated state in the nation.9 Its population is concentrated in the southwest, including suburbs of New York City, and along the Connecticut River around the state capital of Hartford.10 Municipal solid waste and landfill gas supplied by the state's many residents, along with wood and wood waste, provide Connecticut with abundant biomass resources.11

Connecticut is the sixth-lowest energy-consuming state in the nation on a per capita basis. In 2014, the state used less energy per dollar of gross domestic product (GDP) than all but New York and the District of Columbia.12,13 The residential sector leads Connecticut's end-use energy consumption, followed closely by the transportation sector. The industrial sector consumes the least energy.14 Insurance and financial services; real estate; and professional and business services, all of which are relatively low in terms of energy intensity, are the largest contributors to Connecticut's GDP. Other key industries in the state are health care and biosciences; advanced manufacturing; digital media production; green technologies; and tourism.15,16,17

Petroleum

Connecticut's coastal ports and central river are vital links in supplying petroleum products.

Connecticut does not have any petroleum reserves and does not produce or refine petroleum.18 The state receives refined petroleum products at the coastal ports of New Haven, New London, and Bridgeport.19,20 The Connecticut River is an important inland water route for sending petroleum products by barge into central Connecticut. River barges carry motor gasoline, diesel fuel, fuel oil, jet fuel, and asphalt through the middle of the state.21 A product pipeline originating in New Haven also runs north to supply Hartford, Connecticut, and central Massachusetts. The pipeline terminates north of Springfield, Massachusetts.22

More than two-thirds of the petroleum consumed in Connecticut is used in the transportation sector, primarily as motor gasoline.23,24 Connecticut is one of several states that require the statewide use of reformulated motor gasoline blended to reduce smog-forming and toxic pollutants.25,26 The residential sector, where nearly half of Connecticut households use fuel oil or other petroleum products as the primary energy source for home heating, consumes much of the rest of the petroleum used in the state.27,28 Connecticut is phasing in the use of ultra-low sulfur diesel (ULSD) heating oil, with only 15 parts per million of sulfur, by 2018. Nearby states will also require ULSD in 2018 or earlier.29,30 Three Northeast Home Heating Oil Reserve sites have been created by the U.S. Department of Energy to hold ULSD as a buffer against future fuel disruptions. One site is located in Groton, Connecticut.31 The Groton reserve's first release of ULSD was made in November 2012 to alleviate regional fuel delivery shortages resulting from Hurricane Sandy.32

Natural gas

Connecticut does not have any natural gas reserves or production.33 The state receives its supply from interstate natural gas pipelines.34 Almost all of the natural gas arriving in the state comes through the state of New York.35 Historically, natural gas was brought in from producing areas in Canada and from the U.S. Gulf Coast and Mid-Continent regions, but natural gas produced from Appalachian shales, particularly the Marcellus Shale of Pennsylvania, is now arriving in the state.36,37,38,39,40 More than one-third of the natural gas entering Connecticut is shipped on to Rhode Island.41

Assurance of natural gas supply has become a critical energy issue for Connecticut's electricity generators.

One-third of Connecticut households use natural gas as their primary fuel for home heating.42 Like other New England states, Connecticut does not have any underground natural gas storage facilities and depends on pipeline storage and underground storage capacity in nearby states to meet winter peak demand.43 As increasing amounts of natural gas are used for electricity generation, in Connecticut and throughout New England, assurance of natural gas supply has become a critical energy issue for the region.44,45

Coal

Connecticut has no coal resources, and the limited amount of coal consumed for power generation in the state is imported from other countries.46,47 In the past, coal was also shipped to Connecticut from West Virginia mines, but no domestically produced coal has been received in the state since 2011.48,49 Connecticut's use of coal for electricity generation has declined sharply in the past decade.50 Bridgeport Harbor Station Unit 3, the only coal-fired electricity generator still in operation in the state, is scheduled for closure in 2021.51 The plant operator plans to replace it with natural gas-fueled generating capacity.52

Electricity

Natural gas fueled almost half of Connecticut's electricity generation in 2016, surpassing nuclear-powered generation for the first time. In 2015, generation from nuclear power and natural gas were almost equal. Coal-fired generation supplied more than one-tenth of the state's power a decade ago, but, by 2016, coal contributed less than 0.5%.53,54 In 2021, coal-fired power generation in the state will cease with the closure of the Bridgeport Harbor coal plant.55 Biomass, which provides only about 2.4% of state generation, now provides more electricity than either coal or petroleum.56 In Connecticut, electricity generation comes from independent power producers and municipal utilities.57

Connecticut has significant petroleum-fired generating capacity, some of it at dual-fired power plants able to burn petroleum products and natural gas. Although about three-tenths of the nameplate generating capacity in Connecticut is petroleum-fired, petroleum contributed less than 0.3% of the state's net generation in 2016.58,59 The higher-cost petroleum fuels are used in periods of peak power demand, particularly in winter when natural gas supplies are constrained.60,61 As older generating units age and their costs rise, they are being shut down, raising concerns about how to replace their generating capacity.62 The regional grid operator, Independent System Operator-New England (ISO-NE), has promoted demand response as one strategy to maintain grid reliability. Connecticut is a leader among the New England states in the amount of power reductions its consumers have committed to make during peak demand times and emergencies.63

ISO-NE identified a number of problems that threatened electric power reliability in Connecticut and southern New England as a whole. In response, a group of related transmission projects, known as the New England East-West Solution, were undertaken. The final project, the Interstate Reliability Project, was completed in December 2015 with the addition of a high-voltage transmission line and upgraded substations in Connecticut, Massachusetts, and Rhode Island. With the completion of the New England East-West Solution transmission projects, regional transmission bottlenecks are being removed.64 Connecticut was a net electricity recipient in the past, but total net generation has typically exceeded retail sales in recent years, and the state has been a net provider of electricity to other states since 2009.65

Per capita electricity use in Connecticut is among the lowest in the nation.66,67 Demand for air conditioning is low during the mild summer months, and fewer than one in six Connecticut households use electricity as a primary source for home heating in winter.68,69,70 Connecticut has the highest average retail electricity rates among the Lower 48 states.71 Connecticut promotes energy efficiency and peak demand reduction to help consumers reduce their power bills.72

Renewable energy

Renewable resources provided about 4% of Connecticut's net electricity generation in 2016. Biomass fueled three-fifths of the state's renewable generation, solar power supplied slightly more than one-fifth, and hydroelectric sources provided most of the rest.73 Most of the biomass generation comes from municipal solid waste. The state's many hydroelectric facilities include a pumped storage hydroelectric plant.74,75

In 2016, more than nine-tenths of the solar PV generation in Connecticut was small-scale, customer-sited generation.

All the utility-scale renewable electricity generation in Connecticut came from hydroelectric power and biomass until late 2013, when a small amount of utility-scale solar photovoltaic (PV) generation came online.76 By 2016, almost 327 megawatts of utility-scale and distributed (small-scale, customer-sited) solar PV capacity had been installed in Connecticut.77 The state has initiated a long-term program to encourage small-scale, behind-the-meter renewable energy resources, such as solar PV panels on residences and businesses.78,79 In 2016, more than nine-tenths of the solar PV generation in Connecticut was distributed generation.80

The state's largest wind potential is on the Long Island Sound coastline, but most of Connecticut lacks wind resources suitable for large-scale generation.81,82 Connecticut's first utility-scale wind project was installed in 2015.83 The state has only 5 megawatts of installed wind electricity generating capacity in operation.84 The regional grid operator has been assessing infrastructure upgrades needed to connect wind resources throughout the region.85

The use of alternative fuels for transportation, including biofuels and electricity, is being promoted in Connecticut.86 The state does not have any ethanol plants, but it does have two biodiesel plants.87 The biodiesel plants use multiple feedstocks and have a combined capacity of more than 24 million gallons per year. New England's largest biodiesel plant is in Bridgeport, Connecticut.88

Connecticut's renewable portfolio standard (RPS) calls for 27% of electricity sold in the state to come from renewable energy sources by 2020. Most of that electricity (20%) is expected to come from sources such as sustainable biomass; onshore or offshore wind; solar power; ocean, wave and tidal energy; landfill gas; and fuel cells. The RPS allows an additional 3% to come from trash-to-energy, older hydroelectric, or older biomass facilities that meet specific emissions criteria. Another 4% must come from combined heat and power or waste-heat recovery systems that meet specific criteria at commercial and industrial facilities, or from conservation.89 The state also requires retail utilities to offer net metering and time-of-use pricing to encourage the use of renewable resources and energy efficiency.90,91 In 2020, Connecticut is projected to account for approximately one-third of the regional renewable energy demand and may need to import more renewable power from New York and Canada.92,93

Endnotes

1 NETSTATE, The Geography of Connecticut, updated February 25, 2016.
2 U.S. Energy Information Administration (EIA), Connecticut Profile Data, Reserves and Supply, accessed May 12, 2017.
3 U.S. Department of Energy, Energy Efficiency and Renewable Energy, Clean Energy in My State, Connecticut Renewable Energy Resource Maps, accessed May 12, 2017.
4 Community Collaborative Rain, Hail & Snow Network, The CoCoRaHS 'State Climates' Series, Connecticut's Climate, An Overview of Climate in Connecticut, accessed May 12, 2017.
5 Connecticut Department of Energy and Environmental Protection, Dams In Connecticut: Their History, Use and Regulation, updated March 15, 2012.
6 Connecticut Department of Energy and Environmental Protection, Renewable Energy, Hydropower, updated August 2016.
7 U.S. Department of Energy, Energy Efficiency and Renewable Energy, WINDExchange, Connecticut Wind Resource Map and Potential Wind Capacity, updated September 24, 2015.
8 U.S. Department of Energy, Energy Efficiency and Renewable Energy, WINDExchange, Connecticut Offshore 90-Meter Wind Map and Wind Resource Potential, updated June 13, 2014.
9 U.S. Census Bureau, American FactFinder, Community Facts, United States, 2010 Census, Compare States for Population, Housing, Area, and Density, Table GCT-PH1.
10 U.S. Census Bureau, Connecticut: 2010, 2010 Census of Population and Housing (June 2012), Table 5, Population, Housing Units, Land Area, and Density: 2010; and Percent Change: 1980 to 2010, p. 7.
11 U.S. EIA, Electricity, Form EIA-860 detailed data, 2015 Form EIA-860 Data, Schedule 3, 'Generator Data' (Operable Units Only).
12 U.S. EIA, State Energy Consumption Estimates 1960 through 2014, DOE/EIA-0214(2014) (June 2016), Table C12, Total Energy Consumption Estimates, Real Gross Domestic Product (GDP), Energy Consumption Estimates per Real Dollar of GDP, Ranked by State, 2014.
13 U.S. EIA, State Energy Consumption Estimates 1960 through 2014, DOE/EIA-0214(2014) (June 2016), Table C13, Energy Consumption Estimates per Capita by End-Use Sector, Ranked by State, 2014.
14 U.S. EIA, State Energy Consumption Estimates 1960 through 2014, DOE/EIA-0214(2014) (June 2016), Table C10, Energy Consumption by End-Use Sector, Ranked by State, 2014.
15 Gray, Jason, "Top 5 Industries of Connecticut, Which Parts of the Economy are Strongest?" Newsmax (February 26, 2015).
16 U.S. Bureau of Economic Analysis, Interactive Data, GDP and Personal Income, Regional Data, Annual Gross Domestic Product (GDP) by State, GDP in current dollars, All industries, Connecticut, 2015.
17 Ct.gov, Industries, accessed May 16, 2017.
18 U.S. EIA, Connecticut Profile Data, Reserves and Supply, accessed May 16, 2017.
19 City of New Haven, Port Authority, Terminals Within Port District, accessed May 16, 2017.
20 Moffatt and Nichol, Connecticut Deep Water Port Strategy Study (September 2012), p. 1, 3–4.
21 City of Middletown, Connecticut, Department of Planning, Conservation, and Development, Harbor Management Plan, Chapter One: Background Information for the Harbor Management Plan, Water and Waterfront Uses and Facilities, accessed May 16, 2017.
22 Hansen, Lee, "Buckeye Pipeline," Connecticut General Assembly, Office of Legislative Research (October 1, 2013).
23 U.S. EIA, State Energy Data System, Table F15, Total Petroleum Consumption Estimates, 2015.
24 U.S. EIA, State Energy Consumption Estimates 1960 through 2014, DOE/EIA-0214(2014) (June 2016), Table C8, Transportation Sector Energy Consumption Estimates, 2014.
25 U.S. Environmental Protection Agency, Gasoline Standards, Reformulated Gasoline, accessed May 16, 2017.
26 U.S. EIA, Petroleum and Other Liquids, Gasoline and Diesel Fuel Update, Reformulated Gasoline Map, accessed May 16, 2017.
27 U.S. EIA, State Energy Data System, Table F15, Total Petroleum Consumption Estimates, 2015.
28 U.S. Census Bureau, American FactFinder, Connecticut, Table B25040, House Heating Fuel, 2011–2015 American Community Survey 5-Year Estimate.
29 State of Connecticut, Substitute House Bill No. 6360, Public Act No. 13-298, An Act Concerning Implementation Of Connecticut's Comprehensive Energy Strategy And Various Revisions To The Energy Statutes, Sec. 46 (a) (2) (2013), accessed May 16, 2017.
30 U.S. EIA, "Heating Oil Futures Contract Now Uses Ultra-Low Sulfur Diesel Fuel," Today in Energy (May 10, 2013).
31 U.S. Department of Energy, Office of Fossil Energy, Northeast Home Heating Oil Reserve (NEHHOR), accessed May 16, 2017.
32 U.S. Department of Energy, Office of Fossil Energy, Northeast Home Heating Oil Reserve (NEHHOR) Releases, accessed May 16, 2017.
33 U.S. EIA, Connecticut Profile Data, Reserves and Supply, accessed May 16, 2017.
34 U.S. EIA, Connecticut Profile Data, Distribution and Marketing, Interstate Natural Gas Pipelines, accessed May 16, 2017.
35 U.S. EIA, International and Interstate Movements of Natural Gas by State, Connecticut, 2010–15, accessed May 16, 2017.
36 Enbridge, Interactive Maps, Infrastructure, Natural Gas Transmission, accessed May 16, 2017.
37 Tennessee Gas Pipeline Company, LLC, System Map, accessed May 16, 2017.
38 Iroquois, System Map, accessed May 16, 2017.
39 U.S. EIA, International and Interstate Movements of Natural Gas by State, Pennsylvania, 2010–15, accessed May 16, 2017.
40 U.S. EIA, International and Interstate Movements of Natural Gas by State, New York, 2010–15, accessed May 16, 2017.
41 U.S. EIA, International and Interstate Movements of Natural Gas by State, Connecticut, 2010–15, accessed May 16, 2017.
42 U.S. Census Bureau, American FactFinder, Connecticut, Table B25040, House Heating Fuel, 2011–2015 American Community Survey 5-Year Estimate.
43 U.S. EIA, Underground Natural Gas Storage Capacity, by State, Total Storage Capacity, Annual, accessed May 17, 2017.
44 ISO-New England, "2014/15 Winter Outlook: Sufficient Power Supplies Expected, But Natural Gas Pipeline Constraints an Ongoing Concern," Press Release (November 20, 2014).
45 ISO-New England, Seasonal System Outlook, Outlook for Winter 2016/2017, accessed May 17, 2017.
46 U.S. EIA, Connecticut Profile Data, Reserves and Supply, accessed May 17, 2017.
47 Bailey, Hugh, "Bridgeport's coal plant in for the long run," CT Post (October 11, 2014).
48 U.S. EIA, Annual Coal Distribution Report 2015 (November 2016).
49 U.S. EIA, Annual Coal Distribution Report, Archive, Domestic distribution of U.S. coal by destination state, consumer, destination and method of transportation, 2011–2014.
50 U.S. EIA, Electricity, Detailed State Data, 1990–2015 Net Generation by State by Type of Producer by Energy Source, accessed May 17, 2017.
51 U.S. EIA, Electricity, Form EIA-860 detailed data, 2015 Form EIA-860 Data, Schedule 3, 'Generator Data' (Operable Coal Units Only).
52 Hladky, Gregory B., "Connecticut's Last Coal-Fired Power Plant to Be Closed," Hartford Courant (February 12, 2016).
53 U.S. EIA, Connecticut Electricity Profile 2015, Table 5, Electric power industry generation by primary energy source, 1990 through 2015.
54 U.S. EIA, Electric Power Monthly (February 2017), Tables 1.7.B, 1.9.B.
55 Hladky, Gregory B., "Connecticut's Last Coal-Fired Power Plant To Be Closed," Hartford Courant (February 12, 2016).
56 U.S. EIA, Electric Power Monthly (February 2017), Tables 1.3.B, 1.4.B, 1.5.B, 1.15.B.
57 ISO-New England, Connecticut, 2013–14 State Profile (February 2014).
58 U.S. EIA, Annual Electric Generator Data, Form-860 Detailed Data, 3_1_Generator, 2015.
59 U.S. EIA, Electric Power Monthly (February 2017), Tables 1.3.B, 1.5.B.
60 Connecticut Department of Energy and Environmental Protection, 2014 Integrated Resources Plan for Connecticut (March 17, 2015), Appendix B, Resource Adequacy, p. B-40–B-42.
61 van Welie, Gordon, State of the Grid: 2016, ISO on Background, ISO New England (January 26, 2016), New England Shifts to Coal and Oil in the Winter, p. 21.
62 ISO-New England, Retirements of Non-Gas-Fired Power Plants, accessed May 17, 2017.
63 ISO-New England, Connecticut, 2013–14 State Profile (February 2014).
64 Tiernan, Tom, "Interstate Reliability Project in New England placed into service," Transmission Hub (December 21, 2015).
65 U.S. EIA, Connecticut Electricity Profile, 2015, Table 10, Supply and disposition of electricity, 1990 through 2015.
66 U.S. EIA, Electric Power Monthly (February 2017), Tables 5.4.B.
67 U.S. Census Bureau, State Population Totals Tables: 2010–2016, Annual Estimates of the Resident Population for the United States, Regions, States, and Puerto Rico: April 1, 2010 to July 1, 2016 (NST-EST2016-01).
68 U.S. EIA, Residential Energy Consumption Survey (RECS), Table HC7.7, Air conditioning in homes in the Northeast and Midwest regions, 2015.
69 Community Collaborative Rain, Hail & Snow Network, The CoCoRaHS 'State Climates' Series, Connecticut's Climate, An Overview of Climate in Connecticut, accessed May 18, 2017.
70 U.S. Census Bureau, American FactFinder, Connecticut, Table B25040, House Heating Fuel, 2011–2015 American Community Survey 5-Year Estimate.
71 U.S. EIA, Electric Power Monthly (February 2017), Table 5.6.B.
72 Connecticut Department of Energy and Environmental Protection, Energy Efficiency, accessed May 18, 2017.
73 U.S. EIA, Electric Power Monthly (February 2017), Tables 1.3.B, 1.10.B, 1.12.B, 1.14.B, 1.15.B, 1.17.B.
74 U.S. EIA, Electricity, Form EIA-860 detailed data, 2015 Form EIA-860 Data, Schedule 3, 'Generator Data' (Operable Units Only).
75 American Society of Civil Engineers, Rocky River Pumped Storage Hydraulic Plant, accessed May 18, 2017.
76 U.S. EIA, Connecticut Electricity Profile 2015, Table 5, Electric power industry generation by primary energy source, 1990 through 2015.
77 Solar Energy Industries Association, State Solar Policy, Connecticut Solar, accessed May 18, 2017.
78 NC Clean Energy Technology Center, DSIRE, Connecticut, Residential Solar Investment Program (June 28, 2016).
79 NC Clean Energy Technology Center, DSIRE, Connecticut, Low-Interest Loans for Customer-Side Distributed Resources (May 12, 2015).
80 U.S. EIA, Electric Power Monthly (February 2017), Table 1.17.B.
81 U.S. Department of Energy, Energy Efficiency and Renewable Energy, WINDExchange, Connecticut Wind Resource Map and Potential Wind Capacity, updated September 24, 2015.
82 U.S. Department of Energy, Energy Efficiency and Renewable Energy, WINDExchange, Connecticut Offshore 90-Meter Wind Map and Wind Resource Potential, updated June 13, 2014.
83 American Wind Energy Association, Connecticut Wind Energy, accessed May 18, 2017.
84 American Wind Energy Association, U.S. Wind Industry First Quarter 2017 Market Report (April 27, 2017), p. 6, U.S. Installed Wind Power Capacity, by State.
85 ISO-New England, Transmission, accessed May 18, 2017.
86 U.S. Department of Energy, Energy Efficiency and Renewable Energy, Alternative Fuels Data Center, Connecticut Laws and Incentives, accessed May 18, 2017.
87 U.S. Energy Information Administration, Connecticut Profile Data, Environment, accessed May 18, 2017.
88 "USA Plants," Biodiesel Magazine (May 11, 2017).
89 Connecticut Department of Energy and Environmental Protection, Public Utilities Regulatory Authority, Connecticut Renewable Portfolio Standard (October 2016).
90 NC Clean Energy Technology Center, DSIRE, Connecticut, Net Metering (October 4, 2016).
91 Direct Energy, Connecticut-Only Time of Use (TOU) Offer, accessed May 18, 2017.
92 Connecticut Department of Energy and Environmental Protection, 2014 Integrated Resource Plan for Connecticut (March 17, 2015), p. 46.
93 Connecticut Department of Energy and Environmental Protection, 2012 Integrated Resource Plan for Connecticut (June 14, 2012), p. 21, 22.