Green Button / ESPI
The Green Button Alliance (GBA) is a nonprofit organization formed to foster the development, compliance, and widespread adoption of the Green Button standard: to enable consumer access to electricity and natural gas energy-usage information—and water-usage information—in both a downloadable, standardized format and through customer authorization of access by third-party providers of services.
Also in the API standards catalog
This standard shows up on both sides of the house — as a data model here, and as a standard applied in API operations. Same standard, two lenses.
See it as an API standard →