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Pennsylvania   Pennsylvania Profile

State Profile and Energy Estimates

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

Last Updated: July 19, 2018

Overview

Pennsylvania supplies coal, natural gas, electricity, and refined petroleum products to the nation.

Pennsylvania, endowed with extensive fossil energy resources, is a leading East Coast supplier of coal, natural gas, electricity, and refined petroleum products to its own industries and to the nation. The Appalachian Mountains hold rich coal resources and run diagonally southwest to northeast through Pennsylvania, dividing the Ohio River valley in the west from the Susquehanna and Delaware River valleys in the east.1 The Marcellus Shale, the largest U.S. natural gas field, follows the arc of the mountains and underlies about three-fifths of the state.2,3

Although three-fourths of Pennsylvania's land is classified as rural, only one-fourth of the state's population lives in rural areas.4 Pennsylvania's largest metropolitan areas center around Philadelphia on the Delaware River and Pittsburgh on the Ohio River.5,6 The state's temperate climate varies from the southeast, where it is influenced by the Atlantic Ocean, to cooler areas near the Great Lakes in the northwest, where weather fronts often come from Canada.7,8

Pennsylvania's gross domestic product ranked sixth among the states in 2017.9 Although the state is among the top 10 consumers of coal, natural gas, petroleum products, and electricity,10 it is the second largest net supplier of total energy to other states,11 and its total energy consumption per capita ranks among the lower half of the states.12 The industrial sector leads energy consumption in Pennsylvania.13 Major energy-consuming industries include mining; steel, metals, and machinery manufacturing; chemical products; agriculture and food processing; and tourism.14,15,16

Petroleum

Pennsylvania, site of the first U.S. commercial oil well in 1859,17 has very low economically recoverable crude oil reserves, but continues to produce modest amounts of crude oil, mainly paraffin-based crude oil used for making lubricants.18,19,20 Home to nearly half the East Coast's refining capacity spread among four refineries, Pennsylvania has long been the leading petroleum-refining state in the Northeast.21 Two large refineries on the Delaware River in the Philadelphia area supply a range of products, including ultra-low sulfur diesel (ULSD) heating oil, jet fuel, and motor gasoline. Pipelines from the refineries transport products to other parts of Pennsylvania and to western New York state.22 The refineries were built to process crude oil imported by tanker, but, in 2012, new owners added capability to receive crude oil brought in by rail from U.S. shale formations. However, rail shipments have declined in recent years.23,24,25,26 In 2011, a large refinery, at Marcus Hook, was shut down, and the facility was converted to a refined products terminal.27 The Marcus Hook terminal added the ability to process, store, and ship natural gas liquids from the state's Marcellus Shale.28 Two small refineries are located in northwestern Pennsylvania. One processes crude oil into gasoline, diesel fuel, heating oil, and several grades of asphalts,29 while the other refinery processes crude oil from Pennsylvania and neighboring states into gasoline, fuel oil, waxes, and specialty products like resin blends and camping fuel.30

In addition to petroleum products from local refineries, Pennsylvania receives refined products by the Colonial Pipeline from Texas and by tanker and rail from the Gulf of Mexico.31 Refined products are also imported from Canada, Latin America, Europe, and Africa.32

Nearly one in five Pennsylvania households rely on fuel oil for home heating,33 making Pennsylvania, like much of the U.S. Northeast, potentially vulnerable to distillate fuel oil shortages and price spikes. In 2000, the federal government created the 1-million-barrel Northeast Home Heating Oil Reserve to avert shortages in the Mid-Atlantic and New England states.34 In 2011, the federal government converted the reserve to ULSD, which has less than 15 parts per million (ppm) of sulfur, to correspond with decisions made by most northeastern states to begin requiring either low-sulfur diesel, with 15 ppm to 500 ppm sulfur, or ULSD for heating.35 In 2012, Pennsylvania delayed its low-sulfur heating oil requirements because of uncertainty about operations at state refineries that were the region's major heating oil source,36 but in 2016 the state joined most of the Northeast in requiring low-sulfur heating oil.37

To reduce emissions of smog-forming pollutants, motorists in the heavily populated areas of southeastern Pennsylvania, including Philadelphia, are required to use reformulated motor gasoline blended with ethanol. Drivers in the Pittsburgh area must use motor gasoline blended with low vapor pressure in summer.38,39

Natural gas

The Marcellus Shale has made Pennsylvania the second-largest natural gas-producing state.

Pennsylvania is second only to Texas in estimated proved natural gas reserves, which more than quadrupled from 2010 to 2016 because of development in the Marcellus Shale.40 The Marcellus formation extends under three-fifths of Pennsylvania and parts of West Virginia, New York, Ohio, and Maryland.41 It has the largest estimated proved reserves of any U.S. natural gas field.42 During 2016 alone, Pennsylvania added 6.1 trillion cubic feet of natural gas proved reserves, the largest net increase of all the states that year as a result of development of the Marcellus shale.43 Pennsylvania's natural gas production was almost 10 times larger in 2017 than in 2010.44 In 2017, marketed natural gas production reached nearly 5.5 trillion cubic feet, about one-fifth of all U.S. production, keeping Pennsylvania the second largest natural gas producer in the nation, after Texas.45

In the past, natural gas production in Pennsylvania outpaced the ability of regional infrastructure to process and transport it out of the region. Several pipeline projects in recent years have alleviated these constraints. These projects include the Rockies Express Zone 3 expansion, which entered into service in October 2016 and moves natural gas westward from southwest Pennsylvania, and the Algonquin Incremental Market pipeline, which began operating in December 2016 and primarily moves natural gas from northeastern Pennsylvania into New England.46 Most of the natural gas shipped by pipeline from Pennsylvania goes to New Jersey, New York, Maryland, and West Virginia.47 Pennsylvania has 48 underground natural gas storage facilities, the most of any state, and almost all of them are in depleted natural gas fields. The state's total natural gas storage capacity is the fourth largest in the nation.48

Pennsylvania is experiencing parallel growth in the production of natural gas plant liquids (NGPLs), including ethane and propane.49,50 The state's natural gas processing grew more than eight-fold from 2010 to 2016,51 and producers are building processing plants to extract higher-priced NGPLs from the natural gas, and pipelines to transport the products to domestic and Canadian markets and to ports on the East Coast and Gulf Coast for export.52,53,54 Pennsylvania's first ethane cracker, which will make feedstocks for plastics manufacturing from ethane, is in development.55,56

Half of all Pennsylvania households use natural gas as their primary heating fuel,57 but electric power sector consumption has grown rapidly in recent years, surpassing both the residential and industrial sectors as the state's largest natural gas consumer. The electric power sector uses nearly half of all natural gas consumed in the state. The residential sector and the industrial sector each consume about one-fifth.58

Coal

Pennsylvania holds nearly all the U.S. reserves of anthracite coal.

Pennsylvania, the third-largest coal-producing state in the nation, has been home to coal mining for more than 200 years and still has substantial reserves of bituminous coal, which is used to generate electricity and to produce coke for steelmaking.59,60 Northeast Pennsylvania also has virtually all the nation's reserves of anthracite coal, but anthracite accounts for a minimal share of the state's total coal production.61,62,63 Anthracite, which has a higher heat value than other kinds of coal and burns with little soot, is used primarily in space heating.64 The number of coal mines and coal production in Pennsylvania, as in the rest of the nation, has declined in recent years as less electricity is generated by burning coal and coal-fired electricity generating stations have shut down.65,66 However, in 2017, coal production for both Pennsylvania and the United States as a whole increased, mostly because of a rise in U.S. coal exports.67,68 Pennsylvania remains one of the three largest coal-producing states in the nation69 and is home to the Bailey Mine, one of the most productive coal mines east of the Mississippi River.70

Pennsylvania is also among the nation's major coal consumers.71 Four-fifths of the coal consumed in the state is burned for electricity generation, and the rest is consumed for steelmaking and other industrial uses.72 Large volumes of coal are moved by rail, barge, and truck into and out of Pennsylvania and around the state. In 2016, more than 90% of Pennsylvania-mined coal was used for electricity generation. Almost one-third of that coal was used at in-state power plants and the rest was burned at generating facilities in other states throughout the East and Midwest.73 Pennsylvania electricity generators and industries brought in more than half of the coal they consumed from nearby states.74 Pennsylvania is among the nation's leading coal-exporting states. In 2016, about one-seventh of the coal mined in Pennsylvania was exported to other nations, and, in recent years, exports have reached as much as one-fourth of state output.75,76

Electricity

Pennsylvania is one of the top three producers of electricity in the nation.

Pennsylvania is the third highest electricity-generating state in the nation, behind only Texas and Florida. Electricity generation regularly exceeds Pennsylvania's power consumption, making the state an important electricity supplier to the Mid-Atlantic region.77,78 In 2017, nuclear power was the largest electricity generator in the state, followed by natural gas-fired generation.79 The residential sector is the largest consumer of electricity, using more than one-third of the power consumed in the state.80 One in five Pennsylvania households use electricity as their primary heating source.81

The regional electricity grid serving Pennsylvania is managed by the PJM Interconnection,82 and the state's wholesale power market is supplied with electricity almost entirely by independent power producers.83 Many of the state's coal-fired generating plants are older, and, with the increased availability of competitively-priced natural gas, about one-third of Pennsylvania's coal-fired generating capacity shut down between 2010 and the end of 2017. In the same period, natural gas-fired capacity grew by nearly two-thirds.84,85 In 2010, coal provided almost half of the state's net electricity generation, and natural gas accounted for 15%. By 2017, coal had declined to one-fourth of net generation, and natural gas generated almost one-third of the state's net electricity.86

Pennsylvania ranks second in the nation, after Illinois, in nuclear electricity generating capacity,87 and nuclear power is the state's largest source of generation. The state's five nuclear stations have typically provided more than one-third of all net electricity generation since 2001.88 However, the stations face economic challenges from Pennsylvania's new abundance of natural gas, and shut down plans have been announced for 2019 for the Three Mile Island Unit 1 reactor.89,90 Pennsylvania is the site of the first commercial U.S. nuclear power plant, which operated at Shippingport for 25 years, and the site of the nation's most serious nuclear power accident, a partial core meltdown at the Three Mile Island Unit 2 reactor in 1979. That accident led to sweeping changes in U.S. nuclear regulation and operating standards.91

Renewable energy

Wind generation has surpassed hydropower to become Pennsylvania’s largest source of renewable electricity.

Pennsylvania obtains about 5% of its net electricity generation from renewable energy sources. Until recently, renewable electricity came mostly from hydroelectric and biomass power plants. However, wind power has grown to provide two-fifths of renewable electricity generation, making it the state's largest renewable source, even though generation from hydropower and biomass increased during 2017 while wind power declined slightly.92 Appalachian Mountain crests, mainly in Pennsylvania's southwest but also in the northeast section of the state, have wind resources suitable for commercial power production.93 Pennsylvania's first commercial wind farm started generating electricity in 2000 and was dismantled in late 2016.94 The state now has 24 operating wind farms with nearly 1,400 megawatts of capacity.95

Hydropower and biomass each provide about three-tenths of Pennsylvania's renewable electricity.96 The state's hydroelectric facilities are, on average, nearly 60 years old.97 Some older hydropower facilities have been modernized and upgraded for more efficient operation.98,99 Biomass generation comes mainly from municipal solid waste and landfill gas.100 Pennsylvania is among the top dozen states in the amount of electricity generated by biomass resources.101

While solar energy produces substantially less than 1% of the state's net electricity generation, the number of solar photovoltaic (PV) installations in Pennsylvania has increased.102,103 In 2017, 80% of the state's net solar generation came from distributed (customer-sited, small-scale) generating facilities, such as rooftop solar PV, with capacities of less than 1 megawatt.104 A number of large businesses have turned to rooftop solar PV for their power supplies.105 The state's largest solar PV facility has 10 megawatts of generation capacity and came online in 2012.106

Pennsylvania's alternative energy portfolio standard (AEPS) requires that 18% of electricity provided by generation and distribution companies come from renewable sources by 2021, with at least 0.5% from solar power.107 Among the resources Pennsylvania recognizes as meeting part of its AEPS requirements are byproducts of pulping and wood manufacturing, geothermal energy, and waste coal.108 The state also requires investor-owned utilities doing business in the state to undertake energy efficiency measures to reduce peak demand and electricity consumption, which may include helping customers to install solar and geothermal technologies, as well as to insulate buildings and upgrade appliances. The Pennsylvania Public Utility Commission reviews efficiency progress and adjusts goals every five years. The current efficiency goals require that a portion of each utility's objectives be met by specific savings in the low-income, government, and nonprofit sectors.109,110

Endnotes

1 NETSTATE, Pennsylvania, The Geography of Pennsylvania, updated February 25, 2016.
2 U.S. Energy Information Administration (EIA), Top 100 U.S. Oil and Gas Fields (March 2015), p. 4, 8.
3 Pennsylvania Independent Oil & Gas Association, The Marcellus Shale: Pennsylvania's Home-Grown Energy Source, accessed June 21, 2018.
4 The Center for Rural Pennsylvania, Rural Pennsylvania and the 2010 Census (September 2011), p. 2.
5 U.S. Census Bureau, American FactFinder, Table: PEPANNRES, State: Pennsylvania, Population Estimate by Counties, Annual Estimates of the Resident Population: April 1, 2010 to July 1, 2017, 2017 Population Estimates.
6 U.S. Census Bureau, 2010 Census: Pennsylvania Profile, Population Density by Census Tract.
7 City-data.com, Pennsylvania Climate, accessed June 21, 2018.
8 Knight, Paul, "Pennsylvania: Where It Can Rain on Everyone's Parade..." Community Collaborative Rain, Hail & Snow Network, State Climate Series, accessed June 21, 2018.
9 Statista, Gross Domestic Product (GDP) of the United States in 2017, by state (in billion current U.S. dollars), accessed June 25, 2018.
10 U.S. EIA, State Energy Data System, Table C11, Energy Consumption Estimates by Source, Ranked by State, 2016.
11 U.S. EIA, State Energy Data System, Table P3, Energy Production and Consumption Estimates in Trillion Btu, 2016.
12 U.S. EIA, State Energy Data System, Table C13, Energy Consumption Estimates Per Capita by End-Use Sector, Ranked by State, 2016.
13 U.S. EIA, State Energy Data System, Table C10, Total Consumption Estimates by End-Use Sector, Ranked by State, 2016.
14 Byrne, Dennis, "Top 5 Industries in Pennsylvania: Which Parts of the Economy Are Strongest?" Newsmax (April 10, 2015).
15 U.S. Bureau of Economic Analysis, Regional Data, GDP & Personal Income, Begin using the data, Annual Gross Domestic Product (GDP) by State, GDP in Current Dollars, NAICS, All Industries, Pennsylvania, 2015, 2016, 2017.
16 Pennsylvania Department of Community & Economic Development, Key Industries, accessed June 21, 2018.
17 American Oil & Gas Historical Society, First American Oil Well, accessed June 21, 2018.
18 U.S. EIA, Crude Oil Proved Reserves, Reserves Changes, and Production, Pennsylvania, Annual, 2011-16.
19 U.S. EIA, Crude Oil Production, Annual-Thousand Barrels, 2012-17.
20 Pennsylvania Independent Oil & Gas Association, PA Oil and Gas, accessed June 25, 2018.
21 U.S. EIA, Refinery Capacity Report 2018 (June 2018), Table 1, Number and Capacity of Operable Petroleum Refineries by PAD District and State as of January 1, 2018.
22 U.S. EIA, Potential Impacts of Reductions in Refinery Activity on Northeast Petroleum Product Markets, updated May 11, 2012.
23 Maykuth, Andrew, "More Oil Moves by Rail and It Moves Here," Philadelphia Inquirer (April 12, 2015).
24 Loyd, Linda, "Delta reaffirms its commitment to the Trainer oil refinery: ‘We're not selling it'" Philly.com (March 15, 2017).
25 Renshaw, Jarrett, "Once thriving Philadelphia-area rail terminal now a symbol of oil bust," Reuters (May 27, 2016).
26 U.S. EIA, Movements of Crude Oil and Selected Products by Rail between PAD Districts, Crude Oil, Annual-Thousand Barrels, 2012-17.
27 U.S. EIA, Refinery Capacity 2018 (June 2018), Table 13, Refineries Permanently Shutdown By PAD District Between January 1, 1990 and January 1, 2018.
28 Sunoco Logistics, Natural Gas Liquids (NGLs), Marcus Hook Industrial Complex, accessed June 21, 2018.
29 United Refining Company, About United Refining-Our History, accessed June 21, 2018.
30 American Refining Group, Inc., Refinery Information, accessed June 6, 2017.
31 U.S. EIA, Potential Impacts of Reductions in Refinery Activity on Northeast Petroleum Product Markets, updated May 11, 2012, p. 6, 7.
32 U.S. EIA, Petroleum & Other Liquids, Company Level Imports, all months, 2017, 2016, 2015.
33 U.S. Census Bureau, American FactFinder, Pennsylvania, Table B25040, House Heating Fuel, 2012-16 American Community Survey 5-Year Estimates.
34 U.S. Department of Energy, Office of Fossil Energy, Northeast Home Heating Oil Reserve, accessed June 21, 2018.
35 U.S. Department of Energy, Office of Fossil Energy, Northeast Home Heating Oil Reserve History, accessed June 21, 2018.
36 Kerr, Jeffrey, "CME to Change Heating Oil Futures Specs to Reflect Sulfur Change," Reuters (March 23, 2012).
37 Brown, Beth, and David Henry, "Colonial Pipeline to Stop Shipping High Sulfur Heating Oil in June," Platts (April 23, 2015).
38 U.S. Environmental Protection Agency, Gasoline Standards, Programs, Reformulated gasoline and Reid Vapor Pressure, accessed June 21, 2018.
39 American Fuel & Petrochemical Manufacturers, State Motor Fuels Specifications, Map (January 2018).
40 U.S. EIA, U.S. Crude Oil and Natural Gas Proved Reserves, Year-End 2016 (December 2017), Table 10, Natural gas proved reserves, reserve changes, and production, wet after lease separation, 2010-15.
41 Pennsylvania Independent Oil & Gas Association, The Marcellus Shale: Pennsylvania's Home-Grown Energy Source, accessed June 21, 2018.
42 U.S. EIA, Top 100 U.S. Oil and Gas Fields (March 2015), p. 4.
43 U.S. EIA, U.S. Crude Oil and Natural Gas Proved Reserves, Year-end 2016 (February 2018), Natural Gas Highlights, p. 1.
44 U.S. EIA, Pennsylvania Natural Gas Gross Withdrawals, 1967-2017.
45 U.S. EIA, Natural Gas Gross Withdrawals and Production, Marketed Production, Annual-Million Cubic Feet, 2011-17.
46 U.S. EIA, "Pennsylvania's natural gas production continues to increase," Today in Energy (April 23, 2018).
47 U.S. EIA, International and Interstate Movements of Natural Gas by State, Pennsylvania, 2011-16.
48 U.S. EIA, Underground Natural Gas Storage Capacity, Total Storage Capacity, Annual, Total Number of Existing Fields, Annual, and Number of Depleted Fields, Annual, 2011-16.
49 U.S. EIA, Natural Gas Plant Field Production, PADD 1, Annual-Thousand Barrels, 2012-17.
50 U.S. EIA, "Pennsylvania's natural gas production continues to increase," Today in Energy (April 23, 2018).
51 U.S. EIA, Natural Gas Plant Processing, Natural Gas Processed, Annual, 2011-16.
52 Cocklin, Jamison, "Shell's Ethane Pipeline for Pennsylvania Cracker Slated for 2020 Commissioning," Natural Gas Intelligence (June 20, 2018).
53 Sunoco Logistics, Natural Gas Liquids (NGL) Segment, accessed June 23, 2018.
54 The Williams Companies, Ohio Valley Ethane Pipeline, Overview, accessed June 23, 2018.
55 Litvak, Anya, "Shell ethane-cracker plant moves forward with local approval," Pittsburgh Post-Gazette (January 11, 2017).
56 Shell Global, Our Growth Projects, U.S. Pennsylvania Petrochemicals Complex, accessed June 23, 2018.
57 U.S. Census Bureau, American FactFinder, Pennsylvania, Table B25040, House Heating Fuel, 2012-16 American Community Survey 5-Year Estimates.
58 U.S. EIA, Natural Gas Consumption by End Use, Pennsylvania, Annual, 2012-17.
59 Pennsylvania Department of Environmental Protection, Coal Mining in Pennsylvania, accessed June 22, 2018.
60 U.S. EIA, Annual Coal Report 2016 (November 2017), Table 15, Recoverable Coal Reserves at Producing Mines, Estimated Recoverable Reserves, and Demonstrated Reserve Base by Mining Method, 2016.
61 Pennsylvania Department of Environmental Protection, Distribution of Pennsylvania Coals (1992).
62 U.S. EIA, U.S. Coal Reserves (November 15, 2017), Table 14, Recoverable Coal Reserves and Average Percentage at Producing Mines by State, 2016 and 2015.
63 U.S. EIA, Annual Coal Report 2016 (November 2017), Table 6, Coal Production and Number of Mines by State and Coal Rank, 2016.
64 Sunshine, Wendy Lyons, All About Anthracite Coal, Common Uses, The Balance (June 15, 2018).
65 U.S. EIA, Annual Coal Report 2016 (November 2017), Table 1, Coal Production and Number of Mines by State and Mine Type, 2016 and 2015; also see Annual Coal Reports for 2015, 2014, 2013.
66 U.S. EIA, "Electric power sector consumption of fossil fuels at lowest level since 1994," Today in Energy (May 29, 2018).
67 U.S. EIA, Quarterly Coal Report, October-December 2017 (April 2018), Table 2, Coal Production by State, Year to Date 2017 and 2016.
68 U.S. EIA, Quarterly Coal Report, October-December 2017 (April 2018), Table 7, U.S. Coal Exports, Year to Date 2017 and 2016.
69 U.S. EIA, Quarterly Coal Report, October-December 2017 (April 2018), Table 2, Coal Production by State, Year to Date 2017 and 2016.
70 U.S. EIA, Annual Coal Report 2016 (November 2017), Table 9, Major U.S. Coal Mines, 2016.
71 U.S. EIA, State Energy Data System, Table F17, Coal Consumption Estimates and Imports and Exports of Coal Coke, 2016.
72 U.S. EIA, Annual Coal Report 2016 (November 2017), Table 26, U.S. Coal Consumption by End-Use Sector, Census Division, and State, 2016 and 2015.
73 U.S. EIA, Annual Coal Distribution Report 2016 (November 2017), Domestic distribution of U.S. coal by origin State, consumer, destination and method of transportation, Pennsylvania, Table OS-21.
74 U.S. EIA, Annual Coal Distribution Report 2016 (November 2017), Domestic distribution of U.S. coal by destination State, consumer, destination and method of transportation, Pennsylvania, Table DS-37.
75 U.S. EIA, Annual Coal Distribution Report 2016 (November 2017), Domestic and foreign distribution of U.S. coal by origin state.
76 U.S. EIA, Annual Coal Distribution Report, Archive, Domestic and foreign distribution of U.S. coal by State of origin, 2011-15.
77 U.S. EIA, Electric Power Monthly (February 2018), Tables 1.3.B, 5.4.B.
78 U.S. EIA, State Electricity Profiles, Pennsylvania Electricity Profile 2016, Table 10, Supply and disposition of electricity, 1990 through 2016.
79 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
80 U.S. EIA, Electricity Data Browser, Pennsylvania, Retail sales of electricity, annual, 2001-17.
81 U.S. Census Bureau, American FactFinder, Pennsylvania, Table B25040, House Heating Fuel, 2012-16 American Community Survey 5-Year Estimates.
82 U.S. Federal Energy Regulatory Commission, Electric Power Markets: PJM, updated August 23, 2017.
83 U.S. EIA, Electric Power Monthly (February 2018), Table 1.3.B.
84 U.S. EIA, Electric Power Monthly (February 2018), Table 6.2.C.
85 U.S. EIA, Electricity, Detailed State Data, 1990-2016 Existing Nameplate and Net Summer Capacity by Energy Source, Producer Type and State (EIA-860).
86 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
87 U.S. EIA, Electricity, Detailed State Data, 1990-2016 Existing Nameplate and Net Summer Capacity by Energy Source, Producer Type and State (EIA-860).
88 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
89 "Exelon To Retire Three Mile Island Generating Station in 2019," Exelon Corporation, Press Release (May 30, 2017).
90 McGoldrick, Gilian, "One year later: Officials still torn over whether to save TMI from shut down," PennLive.com (May 31, 2018).
91 U.S. Nuclear Regulatory Commission, Backgrounder on the Three Mile Island Accident, updated June 21, 2018.
92 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
93 U.S. Department of Energy, Energy Efficiency and Renewable Energy, WINDExchange, Wind Energy in Pennsylvania, accessed June 25, 2018.
94 National Wind Watch, State's first wind farm being disassembled (November 26, 2016). No link
95 American Wind Energy Association, Pennsylvania Wind Energy, accessed June 25, 2018.
96 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
97 U.S. EIA, Electricity, Form EIA-860 detailed data, 2017 Data, Table 3_1_GeneratorY2017.
98 "PPL Holtwood Doubles Capacity of Hydroelectric Facility," PPL Generation, Press Release (December 2, 2013).
99 Johnson, Kristina, et al., "Adding Power to a Non-Powered Dam: Mahoning Creek," Hydro Review, November 19, 2014.
100 U.S. EIA, Electricity, Form EIA-860 detailed data, 2017 Data, Table 3_1_GeneratorY2017.
101 U.S. EIA, Electric Power Monthly (February 2018), Table 1.15.B.
102 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
103 Pennsylvania Public Utility Commission, 2017 Annual Report, Alternative Energy Portfolio Standards Act of 2004 (September 2016), p. 22-26.
104 U.S. EIA, Electricity Data Browser, Pennsylvania, Net generation for all sectors, annual, 2001-17.
105 Solar Energy Industries Association, Pennsylvania Solar, accessed June 25, 2018.
106 U.S. EIA, Electricity, Form EIA-860 detailed data, 2017 Data, Table 3_1_GeneratorY2017.
107 NC Clean Energy Technology Center, DSIRE, Alternative Energy Portfolio Standard, Pennsylvania, updated January 8, 2018.
108 Pennsylvania Public Utility Commission, 2017 Annual Report, Alternative Energy Portfolio Standards Act of 2004 (September 2016), p. 6.
109 NC Clean Energy Technology Center, DSIRE, Energy Efficiency and Conservation Requirements for Utilities, Pennsylvania, updated June 12, 2015.
110 Pennsylvania Public Utility Commission, Energy Efficiency and Conservation (EE&C) Program, accessed June 25, 2018.