Download bulk historical MOER data from the WattTime API v3 for a grid region and paginate through the full dataset

Steps

1. Register for a WattTime account and obtain an API token by POSTing credentials to the /login endpoint; the response contains a token field (JWT) valid for a limited period — store it securely and refresh it before expiry.
2. Identify the target grid region abbreviation using GET /region-from-loc?latitude={lat}&longitude={lon} or by consulting the WattTime region list; historical MOER data is keyed by region abbreviation (e.g., 'CAISO_NORTH').
3. Request historical MOER data via GET /historical with parameters: region={abbrev}, signal_type=co2_moer, start={ISO8601_datetime}, end={ISO8601_datetime}; the response is a JSON object with a 'data' array of {point_time, value, version} entries at five-minute resolution for most regions.
4. Paginate through large date ranges: if the requested range exceeds the maximum window allowed by your subscription tier, split the request into smaller sub-ranges (e.g., monthly chunks) and concatenate the results; check the response for a 'meta' object indicating truncation.
5. Store the data keyed by (region, point_time) and handle duplicate point_time entries caused by data revisions — WattTime occasionally reissues historical data with corrected values; use the 'version' field to identify the most recent revision.
6. For forecast data (used for carbon-aware scheduling), call GET /forecast with the same region and signal_type parameters — forecast data is a separate endpoint from historical and returns a probabilistic time series for the upcoming 24–72 hours depending on region.