Ofgon / Tool 05 / Heating

Heating Degree Day Comparison

Normalize two entered heating-energy totals by degree days.

Your scenario

Sample values explain the method; they are not recommendations. Replace them, then calculate.

What this tool helps you organize

Normalize two entered heating-energy totals by degree days. It is one defined worksheet, not a complete assessment of your circumstances.

Requires compatible degree-day definitions; does not establish building efficiency.

Method and calculation rules

Divide each period’s heating energy by its entered degree-day total, then compare the ratios.

Display values are rounded for readability. The calculation uses the entered numbers before display rounding. Whole-unit outputs use the rounding rule stated in the method.

Know your inputs

  • Period A heating energy (kWh) — Accepted range: 0 to 1000000.
  • Period A degree days — Accepted range: 0.01 to 1000000.
  • Period B heating energy (kWh) — Accepted range: 0 to 1000000.
  • Period B degree days — Accepted range: 0.01 to 1000000.

A worked example

Illustrative inputs: Period A heating energy (kWh): 900; Period A degree days: 300; Period B heating energy (kWh): 760; Period B degree days: 280.

Period A normalized use: 3 kWh/DD

Period B normalized use: 2.71 kWh/DD

Normalized difference: 0.29 kWh/DD

These sample figures illustrate the formula, not a recommended target or a prediction.

How to use the working copy

Define a single scenario, check the units and replace each sample value that does not match it. Calculate and read all three result components, not just the most favorable number.

Change one assumption to compare scenarios. An edited field makes the previous answer stale; recalculate before downloading or printing. Reset sample clears the open result and restores the example entries.

What the answer cannot establish

Requires compatible degree-day definitions; does not establish building efficiency.

The tool does not verify the accuracy, completeness or current validity of your inputs. Use authoritative current information and qualified judgement when the decision requires them.

Questions about this worksheet

Are the starting values a suggested target?

No. They show how the arithmetic behaves. Use your own checked values and do not infer a recommendation.

Why is my previous result marked stale?

Changing an input means the displayed answer no longer describes the current fields. Recalculate to refresh it.

Can I share an export?

Review the entries and limitations first. A downloaded file is a working copy, not an independently verified report.

Your entries and privacy

The bundled calculation runs in this open browser page. Inputs are not automatically saved as a server-side calculation history. Browser refresh or navigation may clear them.

Contact messages and technical website records are separate from calculator arithmetic. Read the Privacy Policy for the distinction; do not enter confidential records or credentials.