Energy and environment
Electricity, energy prices, floods and water
Energy and environment APIs give electricity generation, prices and carbon intensity, energy statistics, flood warnings and river and water measurements. Use them to show when power is greenest, warn about floods or follow energy prices.
Carbon Intensity API (GB)
The Carbon Intensity API from National Energy System Operator (NESO) gives the carbon intensity of electricity in Great Britain, per half hour, with a forecast up to 48 hours ahead, the generation mix (gas, wind, solar, nuclear ...
EIA Open Data API
The EIA Open Data API from the US Energy Information Administration gives energy statistics: electricity generation and prices, oil and gas production and prices, coal, renewables and forecasts, for example to chart US petrol ...
Energy-Charts API
The Energy-Charts API from Fraunhofer ISE gives electricity data for Germany and other European countries: public power generation per source, prices on the day-ahead market, installed capacity and the share of renewables, for ...
Flood Monitoring API (Environment Agency)
The Flood Monitoring API from England's Environment Agency gives current flood warnings and alerts, and near real-time river levels, flows and rainfall from thousands of measuring stations, for example to warn users about floods ...
USGS Water Data API
The USGS Water Data API gives water data for the United States: monitoring locations on rivers, lakes and wells and their measurements, such as streamflow and water levels, for example to show the current flow of a river. It ...
Compare the energy and environment data APIs
| Service | API key | Formats | Free use |
|---|---|---|---|
| Carbon Intensity API (GB) | Not needed | JSON | Free, no key needed. |
| EIA Open Data API | Needed, free | JSON | Free with a free API key. |
| Energy-Charts API | Not needed | JSON | Free, no key needed. |
| Flood Monitoring API (Environment Agency) | Not needed | JSON | Free, no key needed. |
| USGS Water Data API | Not needed | JSON | Free, no key needed; a free api.data.gov key raises the rate limit. |
Questions
Which free energy and environment data APIs work without an API key?
Carbon Intensity API (GB), Energy-Charts API, Flood Monitoring API (Environment Agency) and USGS Water Data API work without a key, according to their documentation. Most keyless services ask you to keep the number of requests reasonable, and some ask for a User-Agent that names your app.
Are these energy and environment data APIs really free?
The services here can be used without paying, at least on a free plan or free tier, often with limits such as a number of requests per day or non-commercial use only. The table above quotes what each service says about its free use; check the provider's own terms before you rely on it.
How up to date is this list?
The address of every service is checked about once a week, and services that stop working or stop being free are removed. This list last changed on November 8th, 2026.