Home Energy Calculator
Calculate household energy use, cost and emissions across fuel types.
About Home Energy Calculator
Gas has a fixed carbon intensity because it is combusted directly, while grid electricity improves each year as generation decarbonises. On a low-carbon grid, gas heating now emits more per kilowatt hour than electricity. This crossover is why electrification of heating reduces emissions in most countries today, even before accounting for heat pump efficiency.
Formula
Home Energy
Emissions = electricity × grid intensity + gas × 0.183 kg per kWh
- gas intensity
- About 0.183 kg CO2 per kWh of natural gas burned
- grid intensity
- Falls as renewables grow, unlike the fixed figure for gas
Worked example
With the default values below, Home Energy Calculator returns Annual Emissions of 2,717.00. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Annual electricity useminimum 0 kWh
- 3,200 kWh
- Annual gas useminimum 0 kWh
- 11,000 kWh
- Electricity price per kWhminimum 0
- 0.28
- Gas price per kWhminimum 0
- 0.07
- Grid carbon intensityminimum 0 kg/kWh
- 0.22 kg/kWh
Results
- Annual Emissions
- 2,717.00 kg CO2e
- Annual Energy Cost
- $1,666.00
- Emissions From Electricity
- 704.00 kg CO2e
- Emissions From Gas
- 2,013.00 kg CO2e
- Total Energy Use
- 14,200 kWh
Step by step
- 1Values used
- 2Home Energy
- 3Annual Emissions= 2,717.00 kg CO2e
- 4Annual Energy Cost= 1,666.00
- 5Emissions From Electricity= 704.00 kg CO2e
- 6Emissions From Gas= 2,013.00 kg CO2e
- 7Total Energy Use= 14,200 kWh
Assumptions and limits
- The result is derived only from the 5 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax or fees or charges into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Home Energy calculated?
Emissions = electricity × grid intensity + gas × 0.183 kg per kWh Gas has a fixed carbon intensity because it is combusted directly, while grid electricity improves each year as generation decarbonises. On a low-carbon grid, gas heating now emits more per kilowatt hour than electricity.
Why does Home Energy matter?
This crossover is why electrification of heating reduces emissions in most countries today, even before accounting for heat pump efficiency.
What values do I need to enter?
This calculator takes 5 inputs: Annual electricity use, Annual gas use, Electricity price per kWh, Gas price per kWh, Grid carbon intensity. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.