openapi: 3.0.3
info:
  title: NREL Developer Network APIs
  description: >-
    Selected endpoints from the National Renewable Energy Laboratory (NREL)
    developer network covering alternative fuel stations, solar resource and
    PV modeling, and utility electricity rate lookups. All endpoints require
    a developer API key.
  version: 1.0.0
  contact:
    name: NREL Developer Network
    url: https://developer.nrel.gov/
servers:
  - url: https://developer.nrel.gov/api
    description: Production
security:
  - apiKeyQuery: []
paths:
  /alt-fuel-stations/v1.json:
    get:
      summary: Search alternative fuel stations
      description: Retrieve alternative fuel station records with filters for fuel type, state, location, and access.
      parameters:
        - name: fuel_type
          in: query
          schema: { type: string }
          description: Comma-separated list (e.g., ELEC,LPG,CNG).
        - name: state
          in: query
          schema: { type: string }
        - name: zip
          in: query
          schema: { type: string }
        - name: status
          in: query
          schema:
            type: string
            enum: [E, P, T, all]
        - name: access
          in: query
          schema:
            type: string
            enum: [public, private]
        - name: limit
          in: query
          schema: { type: integer }
      responses:
        '200':
          description: Alternative fuel station records.
  /alt-fuel-stations/v1/nearest.json:
    get:
      summary: Find nearest alternative fuel stations
      parameters:
        - name: location
          in: query
          schema: { type: string }
          description: Address or place name.
        - name: latitude
          in: query
          schema: { type: number, format: float }
        - name: longitude
          in: query
          schema: { type: number, format: float }
        - name: radius
          in: query
          schema: { type: number }
          description: Search radius in miles.
        - name: fuel_type
          in: query
          schema: { type: string }
      responses:
        '200':
          description: Nearest stations within the radius.
  /pvwatts/v8.json:
    get:
      summary: PVWatts solar PV system production estimate
      description: Estimate the energy production of grid-connected photovoltaic systems for any location.
      parameters:
        - name: system_capacity
          in: query
          required: true
          schema: { type: number }
          description: System size in kW DC.
        - name: module_type
          in: query
          required: true
          schema:
            type: integer
            enum: [0, 1, 2]
        - name: losses
          in: query
          required: true
          schema: { type: number }
        - name: array_type
          in: query
          required: true
          schema:
            type: integer
            enum: [0, 1, 2, 3, 4]
        - name: tilt
          in: query
          required: true
          schema: { type: number }
        - name: azimuth
          in: query
          required: true
          schema: { type: number }
        - name: address
          in: query
          schema: { type: string }
        - name: lat
          in: query
          schema: { type: number, format: float }
        - name: lon
          in: query
          schema: { type: number, format: float }
        - name: timeframe
          in: query
          schema:
            type: string
            enum: [monthly, hourly]
      responses:
        '200':
          description: Modeled solar PV production output.
  /utility_rates/v3.json:
    get:
      summary: Utility electricity rates by location
      description: Lookup average commercial, industrial, and residential utility rates for a given location.
      parameters:
        - name: address
          in: query
          schema: { type: string }
        - name: lat
          in: query
          schema: { type: number, format: float }
        - name: lon
          in: query
          schema: { type: number, format: float }
      responses:
        '200':
          description: Utility rate information.
  /solar/solar_resource/v1.json:
    get:
      summary: Solar resource data
      description: Average direct normal, global horizontal, and tilt at latitude irradiance for a US location.
      parameters:
        - name: address
          in: query
          schema: { type: string }
        - name: lat
          in: query
          schema: { type: number, format: float }
        - name: lon
          in: query
          schema: { type: number, format: float }
      responses:
        '200':
          description: Solar resource data set.
components:
  securitySchemes:
    apiKeyQuery:
      type: apiKey
      in: query
      name: api_key