Energy / Degree Day API
Access forecast and historical degree-day weather data for energy planning, including irradiance, cloud, precipitation, and temperature fields used in demand and load modeling.
Browse degree-day forecast and historical endpoints designed for energy and utility planning.
Available on Business and Enterprise plans.
- Cooling and heating degree-day support.
- Forecast and historical energy analytics.
- Includes irradiance and solar fields for modeling.
Advantages
Built for Energy Operations: Designed for degree-day tracking, load forecasting, and utility demand analysis.
Forecast + Historical Continuity: Use aligned fields across forecast and historical energy endpoints for model consistency.
Accurate: Data from world class, validated sources.
Frequently Asked Questions
How are heating and cooling degree days calculated?
Degree days estimate heating or cooling demand relative to a selected temperature threshold. We calculate HDD and CDD from hourly temperature values, which better captures intraday swings than a simple daily max/min average.
Read blog postWhat does the `solar_rad` field represent?
The solar radiation field is an estimated surface solar flux value that accounts for cloud cover, surface albedo, and atmospheric effects. Alternatively, GHI/DNI/DHI values are clear-sky values which do not account for these.
Read help articleAvailable APIs
- Energy / Degree Day Forecast API: daily or hourly degree-day forecast support with irradiance and solar fields.
- Historical Energy / Degree Day API: historical degree-day and weather context for retrospective analytics.
Available Fields
| Field | Granularity | Sources |
|---|---|---|
| Cooling degree days (CDD) | daily, hourly, monthly | |
| Heating degree days (HDD) | daily, hourly, monthly | |
| Temperature | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Wet bulb temperature | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Dew point | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Relative humidity | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Cloud cover | daily, hourly, monthly | Forecast: global and regional weather models. Historical: stations, satellite, ERA5 |
| Precipitation | daily, hourly, monthly | Forecast: global and regional weather models. Historical: stations, IMERG, MRMS, ERA5 |
| Snowfall | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Wind speed | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Wind direction | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| 100m max wind speed | forecast daily/hourly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| 100m max wind direction | forecast daily/hourly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Total GHI / DHI / DNI | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Total solar radiation | daily, hourly, monthly | Forecast: global and regional weather models. Historical: RTMA, stations, ERA5 |
| Sun hours | daily, hourly, monthly |
Location Retrieval Methods
- Latitude / longitude
- City name
- Weather station ID
- Airport ICAO code
- Postal (zip) code
- City ID