Purpose of this article
Scaler's calculation engine can be customized to match how your organization estimates consumption, applies conversion factors, and calculates emissions. This article covers the four pieces of that customization: custom consumption formulas, formula custom fields, Formula Reference Tables, and custom emission factors.
Use this when you want to move logic that currently lives in external spreadsheets directly into Scaler, with a full audit trail attached to every computed value.
Custom calculations sit on the Scale plan. If you don't see these settings in your Data Collection Portal, contact your Account Operations representative.
The four building blocks
Block | What it does | Where it lives |
Custom consumption formulas | Populate meter consumption values from formulas built inside Scaler | Asset → Meters and consumption → Add formula consumption |
Formula custom fields | Custom fields whose values are calculated automatically from other fields on the asset | Company → Company settings → Data collection → Custom Data Collection Fields → field type Formula |
Formula Reference Tables | Two-column reference tables (e.g. postal code → conversion factor) that formulas can call | Company → Company settings → Lookup Tables tab (labeled Formula Reference Tables) |
Custom emission factors | Override default emission factors at state, sub-region, or supplier level | Company → Company settings → Emission factors |
Formulas and reference tables are typically used together. Emission factors are independent but follow the same pattern: defaults work for most, overrides for those who need them.
Custom consumption formulas
Formulas let you populate consumption values without entering raw meter readings, using the same syntax patterns you'd use in Excel.
Where to find
Data Collection Portal → Portfolio → Asset list → edit asset → Meters and consumption → Add formula consumption
Supported syntax
- If-statements —
if(condition, value_if_true, value_if_false)
- X-lookups — call into custom lookup tables to retrieve values driven by a key (postal code, property type, country)
- Arithmetic — standard operators across any meter or asset field
- Field references — reference any standard or custom field on the asset (installation type, floor area, postal code, custom field values)
Inline descriptions guide the syntax as you build each formula.
Audit trail
Every formula returns a computed value displayed alongside its source expression. The audit trail records the formula, the input fields used, any lookup tables called, and the resulting value. An auditor can trace any estimation without exporting data.
Different formulas per period or year
Different formulas can be applied to different periods on the same meter (peak / off-peak / shoulder consumption) or to different reporting years if your estimation approach changed over time. Each formula is independently audited.
Worked example: estimating consumption from EPC label and floor area
A common pattern is using an asset's EPC label and floor area to estimate annual consumption when no meter data is available.
- Create a Formula Reference Table called EPC label to EUI with two columns: EPC label (A, B, C, D, E, F, G) and kWh/m²/year value.
- On the meter, add a formula consumption.
- Build the formula:
xlookup([EPC label], 'EPC label to EUI') * [Reporting gross floor area].
- Save. The computed value displays alongside the formula, and the audit trail captures all three inputs (EPC label, lookup table reference, floor area).
Formula custom fields
Custom fields can be defined as formulas: instead of being entered manually, the field's value is calculated from other fields on the asset and recalculates automatically whenever its source data changes. Use them to encode a derived data point or estimation rule once and have every asset compute it.
Where to find
Data Collection Portal → Company → Company settings → Data collection → Custom Data Collection Fields → add or edit a field → set the field type to Formula
Building the formula
- Uses the same Excel-style engine as custom consumption formulas:
IF,XLOOKUP,ROUND,MIN,MAX,ABS, plus arithmetic and comparison operators.
- Reference other custom fields by name (
{Field name}), standard asset attributes (e.g.{asset.gross_floor_area}), and reporting-data values with reporting-year resolution ({reporting.X}).
- Call Formula Reference Tables via XLOOKUP, exactly as in consumption formulas.
- The formula editor includes autocomplete and shows the computed result as you build. Scaler checks for circular references when you save, so a formula can't depend on itself.
A worked example: estimate common area as 10% of gross floor area with {reporting.gross_floor_area} * 0.10.
How computed values behave
- Values are computed asynchronously: allow up to a minute after saving a formula or editing a referenced value for the computed value to appear or refresh. Whenever an underlying value changes, the field recalculates automatically.
- Formula fields display a Formula badge on the asset, making clear the value is calculated rather than manually entered.
- Computed values are available in custom Metrics and Custom Dashboards, like any other custom field value.
Experimental: a formula field can target a reporting-data field and write its computed value directly into it. The interaction with spreadsheet imports and exports is still being defined, so treat write-back as preview functionality rather than a reporting basis.
Formula Reference Tables
Formula Reference Tables are two-column reference tables that formulas can call. Think of them as the Scaler version of x-lookup against a reference sheet in Excel.
Where to find
Data Collection Portal → Company → Company settings → Lookup Tables tab
The feature is labeled Formula Reference Tables on the page. The tab itself still reads Lookup Tables.
Common patterns
- Postal code → energy conversion factor — for regions where consumption is estimated based on postal-code-level coefficients
- Property type → grass-to-net floor area factor — when you only have tenant floor area and need to estimate gross
- Country → fuel mix coefficient — for market-based or contractual energy emissions
- EPC label → kWh/m²/year — for estimation when meter data is unavailable
Creating a table
- Click Add lookup table
- Name the table
- Define the key column (e.g. Postal code) and the value column (e.g. Conversion factor)
- Add rows by typing them in, or paste directly from an Excel reference sheet
Scaler reads the input the same way x-lookup does in a spreadsheet, so existing reference data transfers without restructuring.
Calling from a formula
Once a reference table exists, custom formulas reference it using x-lookup syntax. The lookup uses the asset's value for the key column (for example, the asset's postal code) and returns the corresponding value from the value column. That value feeds back into the formula.
Formula Reference Tables are scoped at the company level, so they're available across all portfolios and assets in your organization.
Custom emission factors
Scaler ships with default emission factors aligned with CRREM and the International Energy Agency. Where your organization uses its own emission factor dataset (regulator-issued, supplier-disclosed, or proprietary), defaults can be overridden.
Where to find
Data Collection Portal → Company → Company settings → Emission factors
Default vs Manual
Each emission factor group has a Default / Manual toggle. Keep defaults where Scaler's values work, switch to manual where your own dataset should apply. Defaults remain visible alongside any overrides so the delta is clear before saving.
Granular geography
- Location-based — editable at state level or e-grid sub-region level depending on country
- Market-based — editable by supplier region
Inline edit or Excel upload
Edit individual values directly in the table, or download the full set, edit in Excel, and upload to apply changes in bulk. All edits are preserved in the audit history.
What's affected when you change factors
Changing an emission factor affects:
- New emissions calculations using that factor from the change forward
- Historical recalculation, if you trigger a reprocess of past periods
It does not affect raw consumption values — only the emissions derived from them.
Waste emission factors and energy purchases / losses also support manual override when those modules are enabled for your account.
How these flow downstream
Custom calculations are inputs to the rest of the platform:
- Custom Metrics dashboard — consumption values populated by formulas appear in metric tables alongside meter-based consumption. See Custom Metrics dashboard.
- Custom Dashboard Builder — the same consumption values feed all charts in the Custom Dashboard Builder. See Custom Dashboard Builder.
- Reports Portal — GRESB, CSRD, and other framework reports use the computed values from custom formulas and custom emission factors the same way they use meter-based data.
- Targets and roadmaps — progress against pathway targets is calculated from the same consumption and emissions values.
Best practices
- Pair formulas with reference tables. A formula that references hard-coded values is brittle. A formula that calls a reference table can be updated centrally when factors change.
- Document each formula. Use the comment field when saving a formula to explain why the logic was chosen. Auditors will thank you.
- Audit emission factor overrides. When you switch a factor from Default to Manual, note the source of the override (regulator publication, supplier disclosure, internal methodology) in the audit comment.
- Don't duplicate defaults. Scaler's CRREM and IEA-aligned defaults are kept current. Override only where your dataset is materially different.
Additional resources
- Using custom fields in Scaler — custom fields can be referenced from formulas
- Customising Scaler end-to-end: from inputs to dashboards — how custom calculations connect to metrics, targets, and dashboards
- Make Scaler your own: Custom features deep dive webinar (May 2026) — watch the live walkthrough