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Use your equipment, operating assumptions and compatible bills to investigate the largest electricity loads.
Examples and calculation text checked September 22, 2026. This is a planning guide, not an individual engineering review.
Where to start
Start with your largest loads
Use your home's equipment and bills
A bill measures electricity over its stated period. An equipment model estimates where that electricity may have gone. These are different kinds of evidence: a bill total does not directly measure each appliance's share.
List the major electric loads and their operating assumptions. For a simple load, watts divided by 1,000, multiplied by running hours, gives kWh. Annual labels, cycle energy and charging consumption can be more useful than maximum wattage for some equipment.
Compare bills over compatible periods, checking dates, missing data and solar net imports. Do not assume a short bill history represents a full year. Check whether planned equipment was operating during those bills before interpreting a difference.
Separate space heating from water heating and identify their fuels.
Count a shared heating/cooling system once, with its uses separated in the result.
Include only the home share of EV charging in home electricity.
Review pool seasons, extra refrigeration and large unknown equipment.
Use an energy-only rate for avoidable energy cost; fixed fees are not automatically saved.
Key Insight
The largest loads depend on your equipment, fuels and habits. Compare electric heating and cooling, hot water, home EV charging and seasonal equipment before assuming your home follows a national percentage split.
Equipment and fuel choices
Occupancy, schedules and seasons
Bill coverage and whether readings are net imports
Existing versus planned equipment
Before making a change
Check the large loads and uncertain assumptions first. Compare a specific change against your existing equipment before deciding whether an upgrade is worth investigating.
These sources explain units and equipment labels. The worked household values are illustrative inputs, not measured customer data or published typical-use ranges.
Follow the free walkthrough to build a household electricity estimate, review its assumptions and compare changes. The optional $19 purchase unlocks both dated PDF report formats for your household profile.
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