Most American warmth travels underground, through a pipe nobody ever looks at. In one corner of the country it travels on a road, inside a tank — and somebody has to remember to order more before it runs out.
Heating oil is not a nationwide habit — it is a regional one, and the region is small. The U.S. Energy Information Administration reports that in the winter of 2023–2024, about 4.79 million households in the whole United States used heating oil as their primary heating fuel, and about 82% of those households were in the Northeast Census Region. Nearly the entire habit lives in one corner of the map.
Basis: U.S. Energy Information Administration, Energy Explained — “Use of heating oil”: “In the winter of 2023–2024, about 4.79 million households in the United States used heating oil (distillate fuel oil) as the primary heating fuel, and about 82% of those households were in the U.S. Northeast Census Region.”
EIA's own explanation is not about the weather at all — it is about what got built underground. EIA's Maine profile says the state uses very little natural gas because of the lack of local distribution infrastructure, and spells out the consequence: most of Maine lacks local natural gas distribution systems, so only about 1 in 12 households rely on natural gas for home heating. A gas furnace is not a choice you can make if the pipe does not come down your street.
Basis: U.S. Energy Information Administration, Maine State Energy Profile — Analysis (last updated December 18, 2025): “Maine uses very little natural gas because of the lack of local distribution infrastructure”; “Most of Maine lacks local natural gas distribution systems, so only about 1 in 12 households rely on natural gas for home heating.”
The oil does not cross the state line in a pipe either. EIA says no interstate petroleum product pipelines enter Maine — inside the state there is one product pipeline, running between Portland and Bangor, but nothing pipes the fuel in from outside. It comes in by water, at the Port of Portland and farther north at Searsport and Belfast, or at border crossings from Canada, which EIA calls the dominant supplier of the petroleum products arriving at all of Maine's ports. Ship, then truck, then tank, then the radiator.
Basis: U.S. Energy Information Administration, Maine State Energy Profile — Analysis: “Although no interstate petroleum product pipelines enter Maine, one intrastate product pipeline runs between Portland and Bangor”; “Most of the rest of the state's refined products enter farther north at Searsport and Belfast, Maine, or at several border crossings from Canada”; “Canada is the dominant supplier of the petroleum products that arrive at all of Maine's ports.”
A supply chain that long makes a country nervous — so it keeps a spare. The U.S. Department of Energy created the Northeast Home Heating Oil Reserve in 2000 to protect consumers in the northeastern states, including Maine, from supply disruptions. It holds 1 million barrels at storage sites in four states, including Maine, where 200,000 barrels of heating oil sits waiting for a winter that goes wrong.
Basis: U.S. Energy Information Administration, Maine State Energy Profile — Analysis: “The U.S. Department of Energy created the Northeast Home Heating Oil Reserve (NEHHOR) in 2000 to protect consumers in the northeastern states, including Maine, from supply disruptions. The NEHHOR holds 1 million barrels at storage sites in four states, including Maine, where 200,000 barrels of heating oil is stored.”
There is a fourth way to be warm here, and it grows outside the window. EIA's Maine profile says “Forests cover about nine-tenths of Maine, the largest share of any state,” and that “about 1 in 10 Maine households use wood as their primary fuel for space heating, the second-highest share among the states after Vermont.” Those two sentences are EIA's, not this page's — but put them together and the shape is familiar: where the pipe never arrived, the fuel that did is the one you can cut down.
Basis: U.S. Energy Information Administration, Maine State Energy Profile — Analysis: “Forests cover about nine-tenths of Maine, the largest share of any state”; “About 1 in 10 Maine households use wood as their primary fuel for space heating, the second-highest share among the states after Vermont.”
Why was the gas network never built out here in the first place? The obvious guess is too few people, too spread out — a pipe under a street is only worth laying if enough houses sit along that street. EIA does say Maine's large rural areas make it the least densely populated state east of the Mississippi River, and that more than three-fifths of its population lives in rural areas, the second-largest proportion of any state after Vermont. But EIA never says that is why the distribution systems are missing; it only reports that they are. So: a good hunch, standing next to a fact, not holding hands with it.
※ A hypothesis is an idea that isn't proven yet.
📊 Sources for the rankings mentioned in this note (links to the original data and retrieval dates) are on each quiz page below.