Energy Usage Categories

Energy Usage Categories (EUC) split a location's consumption into categories such as heating, water heating, washing and cooking, so users can see where their energy goes. Use it to show where the energy went each month, compare periods, or point users to the advice that saves the most.

Before you start

• Profile type. The location must be residential or business. See Location Profile.
• Profile questions. Residential homes need house_type, and business locations need a business type. Answer at least the questions tagged required_for_euc_to_work. The more questions answered, the better the result.
• Location. Coordinates, a street address or a postal code. The more precise, the better.
• Energy data. At least 1 month of daily consumption data. For the best results, 12 months or more at hourly resolution or finer.
• Price formula. Only needed for results in cost. See Price formula model.

Homes with solar panels need PV Disaggregation, which estimates the consumption that EUC splits into categories.

How it works

EUC uses Non-Intrusive Load Monitoring (NILM), also called disaggregation. It reads the location's total consumption together with its profile and estimates how much went to each category. It combines statistical rules with user input and several disaggregation methods, and improves as the profile is filled in.

When a home's usage differs a lot from what the model expects, the result is marked with LOW accuracy. Use this to adjust the wording around the numbers, or to hide them.

API

• GET /v3/locations/{locationId}/euc: returns the categories for a location, period, fuel and unit.

Request at least 28 days and at most 1 year. Common requests:

• A completed month: from the first to the last day of the month.
• Several completed months, such as a calendar year or a quarterly billing period.
• The ongoing month: today and the 28 days before it.

Example

A completed month for one location:

GET /v3/locations/{location_id}/euc?from=2026-09-01&to=2026-10-01&unit=energy&fuel=elec
Authorization: Bearer {access_token}

{
  "accuracy": "medium",
  "total_value": 12881,
  "from": "2026-09-01T00:00:00",
  "to": "2026-10-01T00:00:00",
  "unit": "energy",
  "breakdown": [
    { "category": "heating", "value": 8656, "percentage": 67.2 },
    { "category": "fridge_freezer", "value": 2203, "percentage": 17.1 },
    { "category": "lighting", "value": 1350, "percentage": 10.48 },
    { "category": "washing", "value": 672, "percentage": 5.22 }
  ]
}

Use accuracy to decide how confidently to word the numbers. Full parameters and fields are in the Insights API reference.

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Supported

• Fuels and units. Electricity in energy (kWh) or cost. Gas in energy (kWh or m³) or cost. District heating is not supported.
• Location types. Residential and business. All business locations get Heating, Always on and Other. In the UK, restaurants, shops, grocery stores and primary and secondary schools get more categories.
• Period. 28 days to 1 year.

Categories

• heating: space heating, such as heat pumps, radiators and electric floor heating. Electricity and gas. Residential and business.
• water_heating: hot water for showers and hygiene, from a boiler or heat pump. Electricity and gas. Residential and business.
• washing: washing machines and dryers. Electricity. Residential.
• cooking: stoves, ovens, microwaves, coffee machines and dishwashers. Electricity and gas. Residential and business.
• lighting: all lights. Electricity. Residential and business.
• consumer_electronics: TVs, games consoles, computers, chargers and speakers. Electricity. Residential.
• fridge_freezer: fridges and freezers. Electricity. Residential and business.
• always_on: standby use and anything that never turns off, including ventilation. Electricity. Residential and business.
• cooling: air conditioning, and heat pumps in cooling mode. Electricity. Residential and business.
• electric_vehicle: EV charging at home. Only shown when the profile says the user charges an EV at home. Electricity. Residential.
• sauna: electric sauna. Only shown when the profile says the home has one. Electricity. Residential.
• other: small loads such as vacuum cleaning, and anything that cannot be categorised yet. Electricity and gas. Residential and business.

When there's no data

If EUC cannot return categories, the response carries one of these codes. Show the user what is missing and how to fix it, rather than an empty chart.

• NOT_ENOUGH_DATA_POINTS: not enough consumption data for the requested period.
• DAILY_RESOLUTION_OR_BETTER_REQUIRED_FOR_CUSTOM_PERIOD: a custom period needs daily or hourly data, and the location only has coarser data.
• NOT_SUPPORTED_PROFILE_TYPE: the profile type is missing or not supported.
• HOUSE_TYPE_REQUIRED_FOR_EUC and NOT_ENOUGH_HOME_PROFILE_OPTIONS_SET: the residential profile is incomplete.
• BUSINESS_TYPE_REQUIRED_FOR_EUC, NOT_ENOUGH_BUSINESS_PROFILE_OPTIONS_SET and EUC_NOT_SUPPORTED_FOR_BUSINESS_TYPE: the business profile is incomplete, or the business type is not supported.
• SOLAR_PANELS_ARE_NOT_SUPPORTED_IN_EUC and NO_CONSUMPTION_DATA_FOR_SOLAR_LOCATION: the home has solar panels.
• NO_CATEGORIES_IDENTIFIED: the model found no categories for this location.
• INVALID_PARAMETER: the period is invalid, for example longer than a year.

See the No data scenarios use case below for an example screen.

Use cases

EUC answers questions such as “What uses the most energy?”, “Is heating higher than last month?” and “Where should I start saving?”. Use breakdown, where each category has a value and a percentage, together with total_value and accuracy. Beyond a chart, it works in a monthly email, a message on the bill or an Energy Advisor prompt. The screens below are examples from the Eliq app.

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EUC summary

Show the largest category, or the top three, as a quick summary. Sort breakdown by value and take the first entries.

Show all categories

Show every category for a completed month or year, or for a custom period of at least 28 days.

Different units

Set unit to show the categories in energy or cost. Gas can also be shown in m³. Cost needs a price formula.

Keep your Location Profile up to date

Results get better as the location profile gets more complete. Prompt users to review it now and then, for example after a renovation or a new appliance.

No data scenarios

When EUC cannot return categories, show what is missing and how to fix it, rather than an empty chart. The codes are listed under When there's no data.

Complete vs incomplete month

For a completed month, request from the first to the last day of the month. This gives the most accurate result, whatever the length of the month.

For the ongoing month, request the 28 days up to today, since a period must be at least 28 days.

Label the two differently, so users can tell a final month from one still in progress.

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