generated: '2026-07-27'
method: searched
source: >-
  https://www.hydroone.com/saving-money-and-energy/green-button/third-party-terms-and-conditions
docs:
- https://www.hydroone.com/saving-money-and-energy/green-button/third-party-apps
- https://www.hydroone.com/saving-money-and-energy/green-button/third-party-terms-and-conditions
- https://www.hydroone.com/green-button-cmd-home
note: >-
  Derived from Hydro One's published Green Button third-party documentation and
  terms, and from the live Connect My Data authorization surface. Hydro One
  publishes no OpenAPI, no endpoint reference, and no OAuth discovery document,
  so no securitySchemes could be derived mechanically from a specification.
summary:
  types:
  - oauth2
  - mutualTLS
  oauth2_flows:
  - authorizationCode
  api_key_in: []
  discovery_document: false
  self_serve_credentials: false
schemes:
- name: green-button-cmd-oauth2
  type: oauth2
  flow: authorizationCode
  description: >-
    NAESB ESPI (Green Button Connect My Data) OAuth 2.0 authorization code grant.
    The customer is redirected from the third-party vendor's application to Hydro
    One, authenticates with Hydro One, and consents to release of their energy
    data; the vendor then exchanges the authorization code for an access token and
    retrieves ESPI XML from the CMD resource endpoints.
  authorization_surface: https://www.hydroone.com/green-button-cmd-home
  authorization_url: not published
  token_url: not published
  resource_base_uri: not published
  scope_syntax: 'FB=<function block ids separated by underscores>;historyLength=<seconds>'
  scopes_artifact: scopes/hydro-one-scopes.yml
  credential_issuance: >-
    "The information to assist with the connectivity testing will be provided,
    including Client ID, Client Secret, Test Accounts, URI(s)." Credentials and
    URIs are issued privately by a Hydro One account executive during onboarding
    on the HONI third-party portal — none are published.
  source: https://www.hydroone.com/saving-money-and-energy/green-button/third-party-terms-and-conditions
- name: mutual-certificate-exchange
  type: mutualTLS
  description: >-
    Ongoing Conditions of Participation require the vendor to "exchange with HONI
    and maintain unexpired, unrevoked RSA certificates with a public key length of
    at least 2048 bits issued by a HONI supported Certificate Authority" and to
    "implement Transport Layer Security for all exchanges with HONI."
  minimum_key_length: 2048
  certificate_authority: HONI-supported CA
  source: https://www.hydroone.com/saving-money-and-energy/green-button/third-party-terms-and-conditions
customer_consent:
  initiated_by: customer, from the third-party vendor's site or app
  authentication_at: Hydro One (customer authenticates with the utility, not the vendor)
  vendor_may_authorize_on_behalf_of_customer: false
  vendor_may_authorize_note: >-
    "Can a vendor submit an authorization on behalf of a customer? No. Customers
    must make their own online authorizations through one of the available methods
    and authenticate with the utility before a security token can be exchanged and
    data shared."
  duration: indefinite while the vendor remains authorized
  revocation: customer may revoke access at any time
  suspension: >-
    HONI may suspend vendor access without notice where ordered by the Ontario
    Energy Board or on reasonable evidence of material breach.
access_gate:
  self_serve: false
  gate: application-approval
  steps:
  - Accept the Green Button Third-Party Terms and Conditions.
  - Register on the HONI third-party portal via the onboarding application form.
  - Receive Client ID, Client Secret, Test Accounts and URI(s) privately from a HONI account executive.
  - Complete connectivity testing within 90 days (status moves Ready To Test -> Approved).
  - Exchange and maintain RSA 2048-bit certificates; implement TLS on all exchanges with HONI.
  contact: greenbutton@HydroOne.com
discovery:
  openid_configuration: 'https://www.hydroone.com/.well-known/openid-configuration — HTTP 500 (no discovery document)'
  oauth_authorization_server: 'https://www.hydroone.com/.well-known/oauth-authorization-server — HTTP 500 (no discovery document)'
  oauth_protected_resource: 'https://www.hydroone.com/.well-known/oauth-protected-resource — HTTP 500 (no discovery document)'
related:
- scopes/hydro-one-scopes.yml
- conventions/hydro-one-conventions.yml
- conformance/hydro-one-conformance.yml
- sandbox/hydro-one-sandbox.yml