Table of Contents
Natural Gas vs Electric Heating: Complete Engineering Comparison
Quick Verdict
The gas vs electric heating debate has fundamentally changed with heat pump technology. Traditional electric resistance heating cannot compete with gas on running costs, but heat pumps have flipped the economics.
Bottom Line: Gas heating remains the lowest running cost option for resistance heating comparisons and buildings with existing gas infrastructure. However, electric heat pumps beat gas on both running costs (15-40% lower) and carbon emissions (50-75% lower) in suitable buildings. As gas boilers face regulatory phase-out in new construction across many countries, electric heating—particularly heat pumps—represents the future-proof choice.
The key question isn't "gas or electric" but rather "gas boiler or heat pump"—a comparison covered in our Boiler vs Heat Pump guide.
At-a-Glance Comparison Table
| Feature | Gas Heating | Electric Heating | Winner |
|---|---|---|---|
| Efficiency | 90-95% (boiler) | 100% (resistance) / 300-450% (HP) | Heat Pump |
| Running Cost ($/kWh heat) | 0.087 | 0.25 (resistance) / 0.071 (HP) | Gas or HP |
| Installation Cost | $4,000-10,000 | $500-3,000 (resistance) / $12,000-25,000 (HP) | Resistance |
| Carbon Emissions | 200 g CO2/kWh heat | 60-250 g CO2/kWh heat | Electric (HP) |
| Infrastructure Required | Gas pipeline | Electrical supply | Electric |
| Future Regulatory Status | Phase-out in new builds | Favored | Electric |
| Cooling Capability | None | Reversible HP available | Electric |
| Best For | Existing gas, high demand | New builds, carbon targets | — |
Efficiency: Understanding the Numbers
Efficiency comparisons between gas and electric require understanding fundamentally different metrics.
Technical Note: Gas efficiency (AFUE) and electric efficiency (COP) measure different things. AFUE is heat output ÷ fuel input. COP is heat output ÷ electrical input. A COP of 3.5 doesn't mean 350% of fuel is converted—it means 1 kWh of electricity moves 3.5 kWh of heat from outside to inside.
Gas Heating Efficiency
Gas combustion efficiency is fundamentally limited:
| Technology | Typical Efficiency | Maximum Possible |
|---|---|---|
| Old non-condensing boiler | 70-80% | 85% |
| Modern non-condensing | 80-88% | 88% |
| Condensing boiler | 90-95% | ~98% |
| Gas furnace | 80-98% (AFUE) | ~98% |
Condensing technology recovers latent heat from flue gases, approaching theoretical limits. Further improvements are marginal—gas heating efficiency is essentially mature.
Electric Heating Efficiency
Electric heating spans a wide efficiency range:
| Technology | Efficiency | Mechanism |
|---|---|---|
| Resistance heaters | 100% | Direct conversion |
| Storage heaters | 100% | Direct conversion (off-peak) |
| Electric boiler | 99-100% | Direct conversion |
| Air-source heat pump | 250-400% | Heat transfer (COP 2.5-4.0) |
| Ground-source heat pump | 350-500% | Heat transfer (COP 3.5-5.0) |
Resistance heating converts 100% of electricity to heat—but at electricity prices 2-3× gas, this isn't economical. Heat pumps achieve apparent efficiencies over 100% by moving existing heat rather than creating it.
Verdict: Efficiency
Winner: Heat Pump — Only heat pumps fundamentally outperform gas combustion efficiency. At COP 3.5, heat pumps deliver 3.5× more heat per unit energy than gas combustion's theoretical maximum. Resistance electric is 100% efficient but cannot compete economically.
Running Costs: The Critical Calculation
Running cost determines the ongoing financial impact of your heating choice.
Cost Per Unit Heat
The fundamental calculation:
Gas Boiler (92% AFUE, 0.08/kWh gas):
Cost per kWh heat = 0.08 / 0.92 = 0.087
Electric Resistance (0.25/kWh electricity):
Cost per kWh heat = 0.25
Heat Pump (COP 3.5, 0.25/kWh electricity):
Cost per kWh heat = 0.25 / 3.5 = 0.071
Gas beats electric resistance by 65%. Heat pump beats gas by 18%.
Annual Cost Comparison
For a home requiring 15,000 kWh annual heat:
| Heating Type | Cost per kWh Heat | Annual Cost |
|---|---|---|
| Gas boiler (92%) | 0.087 | $1,305 |
| Electric resistance | 0.250 | $3,750 |
| Electric heat pump (COP 3.5) | 0.071 | $1,065 |
Price Sensitivity: These calculations use typical US energy prices. Local prices vary significantly—some areas have gas at 0.04/kWh (gas wins vs heat pump) while others have electricity at 0.40/kWh (gas wins easily). Always calculate with your actual tariffs.
Break-Even Analysis
At what electricity/gas price ratio does heat pump beat gas?
For COP 3.5 heat pump vs 92% gas boiler:
If electricity is less than 3.2× gas price, heat pumps are cheaper to run. At typical US prices (0.25 vs 0.08), the ratio is 3.1—heat pumps win narrowly. In Europe (higher gas prices), heat pumps win decisively.
Verdict: Running Costs
Winner: Depends — Gas beats electric resistance by 50-70%. Heat pumps beat gas by 10-40% in most markets. The winner depends on local energy prices and heat pump COP achievement.
Carbon Emissions: The Environmental Factor
Carbon emissions increasingly drive heating decisions through regulations, carbon pricing, and corporate/personal climate commitments.
Emissions Per Unit Heat
Gas Heating:
- Natural gas: 184 g CO2/kWh fuel
- At 92% efficiency: 184 ÷ 0.92 = 200 g CO2/kWh heat
- Fixed value regardless of when or where used
Electric Heating:
- Grid carbon intensity varies: 50-500 g CO2/kWh
- Resistance at 200 g CO2/kWh grid: 200 g CO2/kWh heat
- Heat pump (COP 3.5) at 200 g CO2/kWh grid: 200 ÷ 3.5 = 57 g CO2/kWh heat
Regional Grid Carbon Comparison
| Region | Grid Carbon (g/kWh) | Heat Pump Emissions | vs Gas |
|---|---|---|---|
| France (nuclear) | 50 | 14 g/kWh heat | -93% |
| UK (mixed) | 200 | 57 g/kWh heat | -71% |
| US average | 380 | 109 g/kWh heat | -45% |
| Poland (coal) | 700 | 200 g/kWh heat | 0% |
With renewable electricity (solar, wind), electric heating approaches zero emissions.
Future Trajectory
- Gas: Emissions remain constant at ~200 g CO2/kWh heat (no improvement path)
- Electric: Emissions decrease automatically as grids add renewable generation
By 2030-2040, most developed-country grids will have carbon intensity below 100 g/kWh, making heat pump emissions 3-4× lower than gas.
Verdict: Carbon Emissions
Winner: Electric (Heat Pump) — Today, heat pumps emit 40-70% less than gas in most regions. This advantage increases as grids decarbonize. Gas has no path to zero emissions; electric heating becomes cleaner automatically.
Installation Cost Comparison
Installation cost affects both initial affordability and long-term economics.
Cost Breakdown by System Type
| System | Equipment | Installation | Total |
|---|---|---|---|
| Gas boiler (combi) | $2,000-4,000 | $1,500-3,000 | $3,500-7,000 |
| Gas boiler (system) | $2,500-5,000 | $2,000-4,000 | $4,500-9,000 |
| Electric resistance | $200-1,500 | $200-1,000 | $400-2,500 |
| Storage heaters | $2,000-4,000 | $500-1,500 | $2,500-5,500 |
| Air-source heat pump | $6,000-12,000 | $4,000-8,000 | $10,000-20,000 |
| Ground-source heat pump | $10,000-18,000 | $8,000-20,000 | $18,000-38,000 |
Electric resistance is cheapest to install; heat pumps most expensive.
Hidden Costs
Gas Installation:
- Gas connection fee (if not existing): $500-3,000
- Flue installation: Included or $200-500
- CO detector requirement: $30-50
Electric Installation:
- Electrical supply upgrade (if needed): $500-3,000
- Heat pump circuit: $500-1,500
- Hot water cylinder (if needed): $500-1,500
Government Incentives
Many jurisdictions offer significant heat pump incentives:
- UK Boiler Upgrade Scheme: £7,500 ($9,000)
- US Federal Tax Credit: 30% of cost
- Various state/provincial programs: $1,000-10,000
After incentives, heat pump premium over gas often reduces to $2,000-8,000.
Verdict: Installation Cost
Winner: Electric Resistance for absolute cheapest install. Gas for lowest cost central heating. Heat pumps are 2-3× gas installation cost, but incentives narrow the gap significantly.
Application-Specific Recommendations
When to Choose Gas Heating
Use gas heating when:
- Existing gas infrastructure in place (switching cost unjustified)
- High heat demand building (>80 W/m² heat loss) where heat pump sizing is problematic
- Very cheap local gas prices (below 0.05/kWh) beating even heat pumps
- Limited electrical supply with expensive upgrade requirements
- Very cold climate (average winter below -10°C) reducing ASHP performance
- Budget constraints prevent heat pump installation cost
- Short ownership horizon (less than 7 years before payback)
Typical Applications:
- Existing buildings with gas and standard radiators
- Large, poorly insulated properties
- Areas with cheap natural gas
- Budget-constrained retrofits
When to Choose Electric Heating
Use electric heating when:
- No gas supply available or connection cost prohibitive
- New construction (gas bans in effect or anticipated)
- Net-zero carbon or sustainability targets
- Building well-suited to heat pumps (less than 50 W/m² heat loss, UFH)
- Cheap or renewable electricity available
- Cooling requirement (reversible heat pump)
- Long-term ownership planned (>10 years)
Typical Applications:
- New residential and commercial construction
- Rural properties without gas mains
- Buildings with sustainability certification targets
- Properties with solar PV (self-consumption benefit)
- Deep energy retrofits
Heat Distribution Considerations
The choice between gas and electric affects heat distribution options:
Gas Heating Distribution
- Radiators: Standard design, 70-80°C flow, well-established
- Underfloor heating: Possible with mixing valve to reduce temperature
- Warm air: Furnace systems, rapid response
- Hot water: Combi boiler or stored cylinder
Gas works well with all traditional distribution methods at high temperatures.
Electric Heating Distribution
- Resistance: Panel heaters, towel rails, kick-space heaters—room-by-room
- Storage heaters: Off-peak charging, daytime release—limited control
- Heat pump + UFH: Ideal combination, 35-45°C flow, even heat
- Heat pump + radiators: Requires oversized or low-temp radiators
Heat pumps work best with low-temperature distribution (UFH or oversized radiators).
Field Tip: When converting from gas to heat pump, assess your radiators first. If comfortable at boiler setpoint of 55°C or less, existing radiators may suffice. If 70°C+ is needed for comfort, radiators likely need upsizing or UFH addition for heat pump conversion.
Future Regulatory Landscape
Understanding regulatory trends is essential for long-term decisions.
Gas Boiler Restrictions
Many jurisdictions are restricting or banning gas in new construction:
| Region | New Build Gas Ban | Existing Building Phase-out |
|---|---|---|
| UK | 2025 | Under discussion |
| Netherlands | 2018 (enacted) | Gradual district-by-district |
| France | 2022 (new builds) | Under discussion |
| New York City | 2024 (new buildings) | Under discussion |
| California | 2030 (new residential) | Under discussion |
Investment Implications
- Gas heating: May face future restrictions, potential stranded asset risk
- Electric heating: Aligned with policy direction, increasingly required
- Hybrid systems: May offer transition pathway in some jurisdictions
Verdict: Future-Proofing
Winner: Electric — Regulatory trends universally favor electrification. Gas faces increasing restrictions and potential carbon pricing. Electric heating—particularly heat pumps—aligns with decarbonization policy across developed economies.
Common Mistakes to Avoid
| Mistake | Impact | Prevention |
|---|---|---|
| Installing electric resistance as primary heating | 2-3× running costs vs gas or heat pump | Use heat pump or gas for primary; resistance for supplementary |
| Ignoring electricity tariff structure | Missing off-peak opportunities | Check time-of-use rates for storage or heat pump operation |
| Undersizing heat pump from gas | Cold building, backup heater use | Accurate heat loss calculation, professional sizing |
| Comparing gas to resistance only | Missing heat pump economics | Always include heat pump in electric heating comparison |
| Ignoring future regulations | Stranded asset risk | Consider 15-20 year regulatory trajectory |
| Not claiming incentives | Missing significant savings | Research federal, state/provincial, and utility programs |
Related Tools
Use these calculators to evaluate your heating options:
- Heat Loss Calculator - Determine your building's heating requirement
- Radiator Selection Calculator - Size radiators for any supply temperature
- Expansion Tank Calculator - Size system components correctly
Key Takeaways
- Running cost: Gas beats resistance electric by 50-70%; heat pumps beat gas by 15-40%
- Efficiency: Gas 90-95%; resistance 100%; heat pumps 300-450%—only heat pumps fundamentally outperform gas
- When to choose gas: Existing infrastructure, high heat loss, cheap gas, budget constraints
- When to choose electric: No gas available, new builds, carbon targets, heat pump-suitable buildings
- Future-proofing: Electric heating aligns with decarbonization policy; gas faces regulatory pressure
Further Reading
- Boiler vs Heat Pump - Detailed boiler vs heat pump analysis
- Radiator vs Underfloor Heating - Distribution system comparison
- Understanding Heat Loss - Foundation for system sizing
References & Standards
- EN 15316: Energy performance of buildings—Method for calculation of system energy requirements
- ASHRAE Handbook—Fundamentals: Chapter 19, Energy Estimating and Modeling Methods
- EPA ENERGY STAR: Heating and cooling equipment specifications
- IEA Heat Pumps Report: Global heat pump market analysis
- National Grid Future Energy Scenarios: Grid decarbonization projections
Disclaimer: This comparison provides general technical guidance. Running costs depend on local energy prices which vary significantly by location. Always calculate with your actual tariffs and consult qualified professionals for system selection.