Original research · Electrification
The Two Kinds of Electric Heat, and Why a Panel Cares Which One
“Electric heat” is not one electrical load. Resistance heat and a heat pump both run on electricity, and the two make very different demands on the same panel.
Written by HyreElectrical Research Desk Primary-source research and fact checking
The finding
Read this before the numbers: what this page counts, and does not
The electric heating transition page counts equipment, not a transition and not a state. RECS 2020 records what heats each home today, at one point in time. It is not a forecast of how many resistance-heat homes will switch to a heat pump, and it says nothing about a specific home’s wiring — only about the national population of homes running each equipment type.
The resistance/heat-pump split is HyreElectrical’s own calculation, not an EIA row. EIA publishes six equipment categories under the "Electricity" heating fuel; it does not publish a summary resistance-vs-heat-pump line. Every resistance and heat-pump figure below is this desk’s grouping of those six rows, and the grouping rule is stated in full in the method section.
No state or Census-division breakdown, because RECS 2020’s public tables do not support one at the equipment level. Income, construction era and home size are the finest cuts this page can honestly publish for heating EQUIPMENT type. A state figure would require processing RECS’s restricted or public-use microdata file with its replicate weights, which this page has not done.
Nothing here rests on HyreElectrical’s own contractor store. That store is five states and 74% Florida; it has no bearing on a national federal survey and is not used anywhere on this page.
Electric heat, split by equipment: 42.57 million homes, six categories
Source fact. Of 123.53 million US housing units, EIA’s 2020 Residential Energy Consumption Survey found 42.57 million (34.5%) heat primarily with electricity, split across six equipment rows: an electric forced-air furnace, a heat pump, a ductless heat pump (mini-split), built-in electric units (baseboard or wall/ceiling heaters), portable electric heaters, and an unidentified "some other equipment" remainder.
HyreElectrical calculation. Grouping the four resistance-technology rows against the two heat-pump rows gives 25.39 million homes (59.6%) on resistance heat and 17.19 million (40.4%) on a heat pump. Even excluding the small, unidentified "some other equipment" row entirely, resistance heat alone is still 24.50 million homes (57.6%) — a majority either way.
| Equipment (main heating fuel: electricity) | Homes (millions) | Share of electric-heat homes | Category |
|---|---|---|---|
| Electric forced-air furnace | 13.82 | 32.5% | Resistance |
| Built-in electric units (baseboard/wall) | 7.65 | 18.0% | Resistance |
| Portable electric heaters | 3.03 | 7.1% | Resistance |
| Some other equipment | 0.89 | 2.1% | Resistance (default) |
| Heat pump | 16.13 | 37.9% | Heat pump |
| Ductless heat pump (mini-split) | 1.06 | 2.5% | Heat pump |
| Resistance total | 25.39 | 59.6% | — |
| Heat pump total | 17.19 | 40.4% | — |
Component rows sum to 42.58 million against EIA’s published electricity total of 42.57 million — a gap of 0.01 million from independent rounding to the hundredth in EIA’s own tables, not a calculation error.
Why the split matters: two different articles of the Code
A resistance heater turns electricity directly into heat — there is no compressor, no refrigerant, no motor beyond a small circulating fan. Source fact, paraphrased. Fixed resistance space-heating equipment — baseboard heaters, wall and ceiling units, electric-resistance forced-air furnaces — falls under NEC Article 424, "Fixed Electric Space-Heating Equipment," and its branch-circuit rule treats the connected nameplate load as a straightforward continuous load. A heat pump is a different kind of equipment entirely: it moves heat with a refrigerant compressor, which puts it under NEC Article 440, "Air-Conditioning and Refrigerating Equipment" — the same article this desk’s central-air study cites for a central air conditioner’s compressor, because a heat pump is, electrically, an air conditioner that also runs in reverse. Article 440 sizes the branch circuit and its overcurrent protection to the manufacturer’s nameplate minimum circuit ampacity and maximum overcurrent protection — motor-equipment rules, not a flat continuous-load percentage.
HyreElectrical analysis. That is the mechanical reason "electric heat" cannot be treated as one panel-load category. Two homes both counted as "already electric" in every headline electrification statistic can carry electrical loads that are not remotely comparable — one a large, simple resistance load; the other a smaller, motor-governed one — and only the equipment type, not the fuel, tells you which.
ENERGY STAR’s own comparison points the same direction. The joint EPA/DOE program states that an air-source heat pump "is so efficient that it can deliver up to three times more heat energy to a home than the electrical energy it consumes," and separately advises homeowners on "lower energy bills by switching from electric resistance, propane, and oil to heat pumps" — grouping electric resistance with propane and oil, not with heat pumps, as the technology a switch moves away from.
The calculation: a conversion and a replacement are not the same electrical event
The conversion-versus-replacement figure is HyreElectrical’s own arithmetic, built on NEC 220.82(C)’s published demand factors and ENERGY STAR’s stated efficiency range — not a figure either source publishes directly. Every assumption is stated, and the heat-pump efficiency is run at both ends of ENERGY STAR’s "up to three times" range rather than presented as one number.
Resistance-to-heat-pump: converting an existing resistance-heat home
Assumption, stated plainly. A home currently heats with electric baseboard or wall units on fewer than four separately controlled thermostats — a plausible default for exactly the kind of smaller, older home this page’s own data shows resistance heat concentrated in. Under NEC 220.82(C), that qualifies for selection 4: "the nameplate rating(s) of electric space heating if less than four separately controlled units," included at 65% of the connected nameplate.
The home is already wired for 240 volts at the heat source. That is the point this page’s other studies on gas water heating and gas cooking do not get to make: a resistance-heat home has no new circuit to run. The question is only what the calculated LOAD does, not whether a conductor exists.
Removing the resistance elements typically lowers the calculated load. A heat pump sized to deliver the same heat can draw as little as one-third to one-half the electrical nameplate, per ENERGY STAR’s stated "up to three times" ratio, and a heat pump with no supplemental heat is selection 2 — "the nameplate rating(s) of the heat pump when the heat pump is used without any supplemental electric heating" — at 100% of that smaller nameplate. For a 12 kW baseboard system, that is a fall from 7.8 kVA to somewhere between 4.0 and 6.0 kVA, depending where in ENERGY STAR’s range the equipment actually lands.
Keeping the resistance elements as backup can raise it past where it started. Many retrofits leave the old baseboard or add electric-resistance strips as emergency heat for the coldest days, rather than removing them. That configuration is selection 3 — "the nameplate rating(s) of the heat pump compressor and 65 percent of the supplemental electric heating for central electric space-heating systems" — which counts the compressor at 100% and the backup at 65%. On the same 12 kW example, 100% of a 4–6 kW compressor plus 65% of the retained 12 kW backup runs 11.8 to 13.8 kVA — higher than the 7.8 kVA the all-resistance system was calculated at.
Heat-pump-to-heat-pump: replacing equipment that is already there
A different starting point. A home already on a heat pump is already on a dedicated 240-volt branch circuit sized under Article 440 to a compressor’s minimum circuit ampacity. Swapping that unit for a newer one — including a modern cold-climate model, whose inverter-driven compressor often draws a similar or smaller current for the same output — is, in the calculation, frequently a like-for-like reuse of the existing circuit and a near-zero change to the panel’s calculated load.
The variable that actually moves the number is the backup strip, not the heat pump. Cold-climate retrofits commonly add a bigger electric-resistance backup strip than the unit being replaced carried, specifically to guarantee heat on the coldest design day. Under selection 3, every kilowatt of ADDED backup strip adds 65% of a kilowatt — 0.65 kVA — to the calculated load, independent of anything the compressor itself does.
What this means in practice. "Replacing a heat pump" and "converting from baseboard" are not the same electrical question, even though both end with a heat pump in the house. The replacement case turns on one number — how much backup capacity, if any, is added or upsized — while the conversion case turns on whether the old resistance heat is removed or kept.
What this calculation is not
It is not a substitute for a licensed electrician’s own load calculation on a specific panel. NEC 220.82(C) is the optional method for a NEW dwelling; a retrofit or replacement on an existing panel may instead be evaluated under 220.83’s existing-dwelling provisions or 220.87’s measured-demand method — both covered in more detail on this site’s central-air study and load-calculator tool. This section uses 220.82(C)’s published mechanism to illustrate how the Code treats resistance and heat-pump equipment differently, at stated illustrative equipment sizes, not to calculate a specific home’s service requirement.
The conversion, at three baseboard sizes
| Connected baseboard nameplate | Current load — 220.82(C)(4), 65% | Heat pump nameplate needed (ENERGY STAR’s 2×–3× range) | New load if backup removed — 220.82(C)(2), 100% | New load if backup kept — 220.82(C)(3) |
|---|---|---|---|---|
| 8 kW | 5.2 kVA | 2.7–4.0 kW | 2.7–4.0 kVA | 7.9–9.2 kVA |
| 12 kW | 7.8 kVA | 4.0–6.0 kW | 4.0–6.0 kVA | 11.8–13.8 kVA |
| 16 kW | 10.4 kVA | 5.3–8.0 kW | 5.3–8.0 kVA | 15.7–18.4 kVA |
HyreElectrical calculation. The 2× and 3× figures bracket ENERGY STAR’s stated "up to three times" heat-pump efficiency ratio rather than assuming one point value. At every size shown, removing the backup produces a lower calculated load than the original all-resistance system; keeping the backup produces a higher one.
The replacement: what actually moves the number
HyreElectrical calculation. For a home already on a heat pump, the panel-load consequence of a straight equipment swap is close to zero unless the new backup strip is bigger than the old one. Each row below assumes the compressor itself is a load-neutral swap and isolates the effect of the backup-strip decision alone.
| Backup strip added or upsized | Added load — 65% of the addition (220.82(C)(3)) | What that means |
|---|---|---|
| No backup added | 0.0 kVA | Unchanged — a like-for-like circuit reuse |
| 5 kW added | 3.25 kVA | A modest addition, well under a typical dedicated 240 V circuit’s headroom |
| 10 kW added | 6.50 kVA | Comparable to converting a small resistance zone from scratch |
| 15 kW added | 9.75 kVA | Can rival the calculated load of the 8 kW all-resistance system above |
HyreElectrical calculation from NEC 220.82(C)(3)’s published 65% supplemental-heat factor. Actual backup-strip sizing is an equipment and climate decision made by the installer, not a figure this page predicts for any specific home.
Resistance heat’s share, by household income
Source fact, HyreElectrical calculation. This is the cut the RECS 2020 equipment tables support that most coverage of "electric heat" skips: resistance heat’s share of electric-heat homes falls with income, from the high 60s in the two lowest brackets to under half in the top bracket.
| Household income | Electric-heat homes (millions) | Resistance (millions) | Heat pump (millions) | Resistance share |
|---|---|---|---|---|
| Less than $5,000 | 2.10 | 1.41† | 0.55 | 67.1% |
| $5,000–$9,999 | 1.83 | 1.28† | 0.48 | 69.9% |
| $10,000–$19,999 | 4.38 | 2.95† | 1.37 | 67.4% |
| $20,000–$39,999 | 9.41 | 5.87 | 3.53 | 62.4% |
| $40,000–$59,999 | 7.00 | 4.16 | 2.84 | 59.4% |
| $60,000–$99,999 | 9.11 | 5.14 | 3.98 | 56.4% |
| $100,000–$149,999 | 4.63 | 2.42 | 2.21 | 52.3% |
| $150,000 or more | 4.11 | 2.00† | 2.06 | 48.7% |
† Small reconciliation gaps in the two lowest brackets (0.14M and 0.07M) are RECS-suppressed ("Q") cells in the ductless-heat-pump and other-equipment rows, where the sample in that bracket was too thin to publish a figure — treated as zero here and disclosed rather than estimated. EIA RECS 2020, Table HC6.5, retrieved 6 September 2026.
The pattern the contract behind this page flagged
HyreElectrical analysis. Resistance’s share runs 67.1% in the lowest bracket and 69.9% in the second-lowest — both close together and both near the top of the range — then declines in every bracket above that, reaching 48.7% in the $150,000-or-more bracket. That is an 21.3-point spread from the peak bracket to the top one. A resistance-heat home is disproportionately a lower-income home, and a lower-income electric-heat home is disproportionately on the equipment type with the larger, simpler electrical load — which is also, per the ENERGY STAR figures cited above, the less efficient equipment to run. The cooling side of the same retrofit, and the panel arithmetic NEC 220.83 applies to it, is homes without central air conditioning.
We are not going to guess at the causal direction. Lower household income correlates with older, smaller housing units in general, and this page’s own era and size cuts below show resistance heat concentrated in exactly those homes independently of income. Untangling how much of the income pattern is really an age-and-size pattern would need a table that cross-tabulates all three at once, which RECS 2020’s public release does not publish.
Resistance heat’s share, by year built
| Year built | Electric-heat homes (millions) | Resistance share |
|---|---|---|
| Before 1950 | 3.66 | 71.6% |
| 1950–1959 | 2.58 | 60.9% |
| 1960–1969 | 3.49 | 60.7% |
| 1970–1979 | 7.37 | 64.2% |
| 1980–1989 | 7.31 | 59.4% |
| 1990–1999 | 6.62 | 52.0% |
| 2000–2009 | 6.63 | 56.9% |
| 2010–2015 | 2.64 | 57.2% |
| 2016–2020 | 2.26 | 53.1% |
EIA RECS 2020, Table HC6.3, retrieved 6 September 2026. Homes built before 1950 carry the highest resistance share of any era band; the pattern across the middle decades is not a straight line, and this page does not guess at why.
Resistance heat’s share, by home size
| Home size | Electric-heat homes (millions) | Resistance share |
|---|---|---|
| Less than 1,000 sq ft | 14.23 | 73.1% |
| 1,000–1,499 sq ft | 11.37 | 62.3% |
| 1,500–1,999 sq ft | 6.70 | 50.6% |
| 2,000–2,499 sq ft | 4.09 | 43.8% |
| 2,500–2,999 sq ft | 2.31 | 47.2% |
| 3,000 sq ft or more | 3.88 | 37.1% |
EIA RECS 2020, Table HC6.9, retrieved 6 September 2026. This is the widest spread of the three cuts on this page: resistance share very nearly doubles between the largest and smallest home-size bands.
The same pattern, three ways
| Cut | Lower end | Higher end | Spread |
|---|---|---|---|
| By income | 67.1% | 48.7% | 18.5 pts |
| By year built | 71.6% | 53.1% | 18.5 pts |
| By home size | 73.1% | 37.1% | 36.0 pts |
HyreElectrical calculation from the three tables above. Home size shows the largest spread of the three cuts; income and year built are close to each other in magnitude.
Limitations
- The heating figures are an equipment count, not a transition forecast
The figures on this page describe what heats each home today. They say nothing about how many resistance-heat homes intend to convert, on what timeline, or at what rate.
- The resistance/heat-pump grouping is HyreElectrical’s own, not EIA’s
EIA publishes six equipment rows under "Electricity." It does not publish a resistance-vs-heat-pump summary. The 0.89-million "some other equipment" row nationally, and its counterparts in each cut, are grouped as resistance by default; the narrow definition excluding it is published in the national table for comparison.
- No state or division breakdown, because RECS 2020’s public equipment tables do not support one
Income, year built and home size are the finest published cuts for heating equipment type. A state-level figure would require processing RECS’s restricted or public-use microdata with its replicate weights, which this page has not done.
- Income, era and size are three separate cuts, not one cross-tabulation
RECS 2020’s public tables do not cross-tabulate heating equipment by income, year built and home size together. Nothing on this page claims the same household is being counted in more than one of these three tables at once.
- The panel calculation is illustrative arithmetic, not a home-specific measurement
The conversion and replacement figures use NEC 220.82(C)’s published demand factors and ENERGY STAR’s stated "up to three times" efficiency ratio at stated illustrative equipment sizes. A specific home’s calculation depends on its actual nameplates, its climate, its thermostat zoning, and the article an electrician chooses to apply — 220.82, 220.83 or 220.87 — none of which this page measures.
- Small reconciliation gaps in a few brackets are RECS-suppressed cells, not errors
Where a bracket’s resistance-plus-heat-pump sum falls short of EIA’s published electricity total, the gap is a "Q" (withheld) cell treated as zero and disclosed in that table’s note.
Method
Sources. US Energy Information Administration, 2020 Residential Energy Consumption Survey: Table HC6.1 (space heating by housing unit type, for the national equipment split), Table HC6.5 (space heating by household income), Table HC6.3 (space heating by year of construction) and Table HC6.9 (space heating by home size). All four downloaded directly from eia.gov/consumption/residential/data/2020/hc/xls/ on 6 September 2026. ENERGY STAR (a joint EPA/DOE programme), "Air-Source Heat Pumps," retrieved the same day. NEC 220.82(C)’s six selections are quoted verbatim from this site’s own load-calculator tool, itself verified against a 2014-edition reprint (IEEE ICPS chapter library) on 5 September 2026; this page reuses that verified text rather than re-verifying it independently today.
Derivation. "Resistance" sums the published Central warm-air furnace, Built-in electric units, Portable electric heaters and Some other equipment rows under the Electricity fuel heading. "Heat pump" sums the published Heat pump and Ductless heat pump (mini-split) rows. Cells marked "Q" (withheld: relative standard error over 50%, or fewer than 10 households in the reporting sample) or "N" (none in sample) are treated as zero in every sum on this page, and the resulting small reconciliation gaps are disclosed in each table’s note rather than estimated away.
What is not a measurement. NEC Articles 424 and 440 are described here as a paraphrase of their general scope — fixed resistance heating equipment under 424, motor-compressor equipment including heat pumps under 440 — not a verbatim reproduction; NFPA’s text is not freely reproducible online. The heat-pump efficiency ratio used in the calculation is ENERGY STAR’s own stated ceiling ("up to three times"), run at both that ceiling and a more conservative half of it, not a measured figure for any specific piece of equipment.
Reproducibility. Every EIA figure on this page is read directly off a public spreadsheet with no interpretation applied before the sums shown here. Anyone with the same four files, the same six NEC selections and the same stated assumptions can rebuild every row.
Questions
How many US homes heat with electricity?
What share of electric-heated homes use resistance heat instead of a heat pump?
Why does it matter whether electric heat is resistance or a heat pump?
Is resistance electric heat more common in lower-income homes?
Is resistance electric heat more common in older or smaller homes?
Does converting a baseboard-heated home to a heat pump add load to the electrical panel?
Does replacing an old heat pump with a new one require a panel upgrade?
Does this study break the data down by state?
Written and audited by
HyreElectrical Research Desk
Primary-source research and fact checking
We read the model code, the federal safety notice, the municipal fee sheet or the utility tariff ourselves, and we publish the figure with the document it came from and the date we retrieved it. Where a number cannot be traced to a primary source, we publish the shorter page and say what we could not verify. HyreElectrical does not perform, supervise or warrant electrical work. Authorship is organisational: this desk, not a named persona.
- 10
- long-form launch pages in this layout
- 5
- states with verified licence records
- 16,369
- electrical companies in those records
- 74%
- of the store is Florida — disclosed first, not footnoted
How this desk works
- Primary sources only. Code statements come from NFPA 70 as the model code. Safety statements come from CPSC. Permit fees come from the city or county fee sheet. Utility charges come from the filed tariff. We do not cite a blog that cites a source; we open the source.
- Our contractor store is five states, and 74% of it is Florida. Any figure built on that store is titled to those states and names the concentration in the first screen. It is not a national sample of electricians.
- Load calculations on this site are a published simplification in the shape of NEC 220.82 — first 10 kVA at 100%, remainder at 40%, HVAC at 100%, EVSE at 125%. They are labelled as not a stamped calculation. A licensed electrician using the adopted edition does that work.
- No national price for a panel upgrade is shipped. Labour rates, the adopted code edition, whether the utility is involved, and the state of the existing wiring move the invoice too far for a roundup to help. Cost intent lives on the cost page; this page explains the decision.
- We do not perform electrical work, and we take no payment for placement, ranking or a favourable mention. Nobody buys a position on this site.
Data as of 6 September 2026. Authorship on this site is organisational: the analysis belongs to the desk rather than to a named individual, and we do not publish credentials we do not hold. Our editorial policy sets out how we source, date and correct what we publish.
Sources & retrieval dates
- US Energy Information Administration — 2020 Residential Energy Consumption Survey, Table HC6.1 (Space heating in U.S. homes, by housing unit type) , The national equipment split: 13.82 million homes on an electric forced-air furnace, 16.13 million on a heat pump, 1.06 million on a ductless heat pump, 7.65 million on built-in electric units, 3.03 million on portable electric heaters and 0.89 million on some other equipment, out of 42.57 million electric-heat homes and 123.53 million total housing units. Retrieved 6 September 2026.
- US Energy Information Administration — 2020 RECS, Table HC6.5 (Space heating in U.S. homes, by household income) , The eight income brackets and their equipment splits used in the income table, chart and analysis. Retrieved 6 September 2026.
- US Energy Information Administration — 2020 RECS, Table HC6.3 (Space heating in U.S. homes, by year of construction) , The nine construction-era bands and their equipment splits used in the era table. Retrieved 6 September 2026.
- US Energy Information Administration — 2020 RECS, Table HC6.9 (Space heating in U.S. homes, by home size) , The six home-size bands and their equipment splits used in the size table. Retrieved 6 September 2026.
- ENERGY STAR (US EPA / US DOE) — "Air-Source Heat Pumps" , The "up to three times more heat energy... than the electrical energy it consumes" efficiency statement, and the guidance grouping electric resistance with propane and oil as fuels a heat-pump switch moves away from. Retrieved 6 September 2026.
- NFPA 70, National Electrical Code (NEC), Article 220 — Branch-Circuit, Feeder, and Service Calculations , Section 220.82(C)’s six heating-and-cooling selections, quoted verbatim as reproduced in a 2014-edition text (IEEE ICPS chapter library reprint) and reused from this site’s own load-calculator tool. Articles 424 and 440 are cited to the model code generally and described here as a paraphrase, not a verbatim reproduction — confirm the edition your jurisdiction has adopted. Retrieved 5 September 2026.
Converting resistance heat to a heat pump — or replacing one?
The two are different electrical questions. Tell us what your home currently runs on and we will connect you with licensed electrical companies in your area to run the actual calculation.
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HyreElectrical does not perform, supervise or warrant electrical work, and takes no payment for placement, ranking or favourable mention. This is research on published federal survey data and a published model-code mechanism, not advice on a specific property. The panel-load figures are illustrative calculations at stated assumptions, not a quote or a stamped load calculation. We have no commercial relationship with EIA, ENERGY STAR, NFPA, or any manufacturer named above.