â–¶ About this tool — what you need & how it works
Monthly energy bills rise and fall partly because of the weather. Weather normalization fits a regression of each fuel's consumption against degree‑days, then reports the expected (weather‑predicted) usage for every month. The gap between actual and expected isolates changes that aren't explained by weather — retrofits, occupancy, controls, or operational drift.
You'll need, for each month in the period: electricity (kWh), natural gas (therms), geothermal (gallons, if applicable), plus HDD and CDD for the same month.
Getting degree‑days from NOAA:
- Open the NOAA National Weather Service site and pick the nearest data center.
- Go to the NOWData tab and refine the location if needed.
- Under Product, choose Monthly Summarized Data.
- Set the year range, set Variable to HDD (then again to CDD), click Go.
- Copy each month's value into the matching row below.
Seasons follow the standard convention: cooling = May–Sep (regressed against CDD),
heating = Oct–Apr (regressed against HDD). Energy is converted to a common kBtu basis:
1Enter monthly data
One row per billing month. Leave geothermal at 0 if not applicable. Season is assigned automatically.
| Month | Electricity kWh | Natural gas therm | Geothermal gal | HDD | CDD | Season |
|---|
â–¶ Bulk paste from a spreadsheet
Paste tab- or comma-separated rows in the order
Month, Electricity, Gas, Geothermal, HDD, CDD (a header row is fine — it's detected and skipped).
Months can be 2019-05, 5/2019, or May 2019.