Therms to kWh Converter

Therefore 1 therm = 100,000 / 3,412.14156 = 29.3071 kWh.

The conversion is exact because the therm is defined as exactly 100,000 BTU.

The therm is the universal US natural gas billing unit — your monthly residential gas bill reports consumption in therms (or CCF, hundred cubic feet, where 1 CCF contains approximately 1.025 therms at standard gas heat content of 1,025 BTU per standard cubic foot).

This kWh-equivalent conversion is the single most important energy conversion for US building owners and facility managers evaluating whether to heat with natural gas or electricity.

At typical 2024-2026 US utility rates: 1 therm of natural gas costs approximately $1.20-$1.80 (residential, varies regionally), which delivers 29.3 kWh of heating energy — about $0.041-$0.061 per kWh-equivalent.

Residential electricity averages $0.15-$0.18/kWh nationally, making gas heat 2.5-4× cheaper per unit of raw energy.

However, the effective comparison must account for equipment efficiency: a condensing gas furnace at 95% AFUE delivers 0.95 therms of usable heat per therm purchased, while a heat pump with a COP (coefficient of performance) of 3.0 delivers 3 kWh of heat for every 1 kWh purchased.

At $1.50/therm gas and $0.15/kWh electricity, the cost per million BTU of delivered heat is $15.79 for gas (95% AFUE furnace) versus $14.65 for electricity (COP 3.0 heat pump) — remarkably close, and the balance tips with local utility rates, climate (COP varies with outdoor temperature), and carbon pricing.

In commercial and industrial settings, natural gas is often priced in $/MMBTU (dollars per million BTU) rather than $/therm, with 1 MMBTU = 10 therms = 293.07 kWh.

The NYMEX Henry Hub natural gas futures contract trades in $/MMBTU, and the conversion to $/kWh-equivalent is a standard energy market calculation: $3.00/MMBTU = $0.0102/kWh-equivalent, roughly 15× cheaper than wholesale electricity at $0.15/kWh.

This price differential is why natural gas combined-cycle power plants (which convert gas to electricity at ~55-60% thermal efficiency) can profitably sell electricity at $0.03-$0.04/kWh when gas is $3.00/MMBTU.

The therm-to-kWh conversion also underlies the EPA's Energy Star Portfolio Manager, which normalizes all building energy consumption (electricity in kWh, natural gas in therms, steam in klb, chilled water in ton-hours) to a common source energy basis (kBtu or GJ) for the 1-100 ENERGY STAR score.

The EPA's source-site ratio for natural gas is 1.05 (meaning 1.05 units of source energy — including extraction, processing, and transport losses — per 1 unit of site energy delivered as therms), while for electricity it's 2.80 (reflecting the ~65% generation and transmission losses in the US grid), making the source-energy comparison even more favorable to natural gas end-use than the simple site-energy therm-to-kWh conversion suggests.

Where therm-to-kWh conversions appear in real engineering work.

Building energy auditing and commissioning: An ASHRAE Level 2 energy audit involves a comprehensive walk-through and analysis of a building's energy consumption, comparing electricity (in kWh from the utility bill) and natural gas (in therms from the gas utility) on a common basis.

The audit report presents all energy consumption in kBtu or MMBTU: 1 therm = 100 kBtu = 0.1 MMBTU = 29.3 kWh.

A typical office building might consume 500,000 kWh of electricity and 5,000 therms of natural gas annually.

The therm-to-kWh equivalent for the gas: 5,000 × 29.3 = 146,500 kWh-equivalent.

Total energy consumption on a common basis: 500,000 + 146,500 = 646,500 kWh-equivalent.

This unified number is the basis for benchmarking against ENERGY STAR Portfolio Manager and for prioritizing energy conservation measures (ECMs).

Comparing gas heat to electric heat options in building design: When designing a new building or selecting heating equipment for a retrofit, the engineer must compare the operating cost of gas heating (furnace, boiler) versus electric heating (resistance heater, heat pump).

The cost comparison requires three inputs: gas price (in $/therm or $/MMBTU), electricity price (in $/kWh), and equipment efficiency (AFUE for gas, COP or HSPF for electric).

The therm-to-kWh conversion (29.3 kWh/therm) is the foundation: at $1.50/therm, the gas costs $1.50/29.3 = $0.051 per kWh of raw energy.

A 95% AFUE furnace delivers $0.051/0.95 = $0.054 per kWh of delivered heat.

A heat pump at COP 3.0 with electricity at $0.15/kWh delivers $0.15/3.0 = $0.050 per kWh of delivered heat — essentially equivalent to gas at the conditions assumed.

The choice depends on the specific utility rates and climate, but the therm-to-kWh conversion is the bridge.

Utility integrated resource planning (IRP): State utility regulators require investor-owned utilities to file IRPs that document their long-term resource strategy, including demand-side management (DSM) programs and supply-side generation.

DSM savings are typically reported in kWh (electricity reduction) and therms (gas reduction), and the equivalent energy value is computed using the therm-to-kWh conversion.

A DSM program that saves 100,000 therms/year of gas (e.g., a high-efficiency furnace rebate program) is credited with saving 2,930,000 kWh/year of equivalent energy.

This allows the IRP to compare DSM savings against supply-side alternatives on a common basis.

Corporate carbon footprint and ESG reporting: Under the GHG Protocol, companies report Scope 1 (direct combustion, including natural gas burned on-site) and Scope 2 (purchased electricity) emissions.

Natural gas emissions are computed from the therm consumption: 11.7 lb CO₂/therm (EPA default emission factor for US natural gas combustion for heating).

Electricity emissions are computed from the kWh consumption: the EPA eGRID subregion emission factor (lb CO₂/kWh, ranging from 0.2 in Pacific Northwest to 1.5 in coal-heavy regions).

For carbon footprint reporting, the therm-to-kWh conversion is implicit in the per-unit emissions calculation.

A facility burning 1,000 therms/year and consuming 500,000 kWh/year has 11.7 × 1,000 = 11,700 lb CO₂ from gas (5.3 tonnes) and, at the US national average, 0.85 × 500,000 = 425,000 lb CO₂ from electricity (192.8 tonnes).

The total: 198.1 tonnes CO₂/year.

Building electrification cost-benefit analysis: Building electrification (replacing gas heating with heat pumps, gas water heaters with electric, gas stoves with induction) is a major decarbonization strategy.

The cost-benefit analysis must compare the operational cost of gas vs electric heating at the customer's local rates.

The therm-to-kWh conversion (29.3) is the multiplier that converts the gas bill to an electricity-equivalent cost.

A typical US home burning 600 therms/year at $1.50/therm spends $900/year on gas heating.

The same home with a COP 3.0 heat pump would need 600 × 29.3 / 3.0 = 5,860 kWh/year of electricity, costing $879/year at $0.15/kWh — about the same.

The decision depends on climate (COP varies with outdoor temperature), utility rates (the gas-vs-electric price ratio), and the carbon intensity of the grid.

Where therms-to-kWh conversions appear in everyday life.

Reading your residential gas bill: Your gas utility bills you in therms (or CCF, which is converted to therms).

Understanding the bill requires multiplying therms by your utility's gas rate (in $/therm) to get the dollar cost.

The therm-to-kWh conversion is implicit when comparing your gas bill to your electricity bill: if your gas bill shows 50 therms and your electric bill shows 1,500 kWh, your total energy consumption is 50 × 29.3 + 1,500 = 1,465 + 1,500 = 2,965 kWh-equivalent.

This unified number is the basis for any energy reduction goal — reducing 50 therms/year of gas consumption is equivalent to reducing 1,465 kWh/year of electricity in total energy terms.

Comparing space heating options for your home: When deciding between a new gas furnace and a heat pump for home heating, the therm-to-kWh conversion is the foundation of the operating cost comparison.

At typical US residential rates (2024-2026): gas $1.50/therm, electricity $0.15/kWh.

A gas furnace at 95% AFUE: operating cost = $1.50 / 29.3 / 0.95 = $0.054/kWh delivered heat.

A heat pump at COP 3.0 (mild climate): operating cost = $0.15 / 3.0 = $0.050/kWh delivered heat.

A heat pump at COP 2.0 (cold climate): operating cost = $0.15 / 2.0 = $0.075/kWh delivered heat.

The decision depends on your local climate (which determines heat pump COP) and your utility rates.

Energy audits for home improvements: When you hire a home energy auditor or use a tool like ENERGY STAR Home Advisor, the recommendations are typically presented in therms and kWh-equivalent savings.

Adding insulation to your attic might save 50 therms/year of natural gas heating ($75/year at $1.50/therm), which is 1,465 kWh-equivalent.

Sealing air leaks might save another 30 therms/year ($45, or 879 kWh-equivalent).

Adding a heat pump water heater saves 200 kWh/year of electric water heating directly.

The total savings is 2,544 kWh-equivalent per year, the unified metric for energy efficiency improvements.