> ## Documentation Index > Fetch the complete documentation index at: https://docs.axle.energy/llms.txt > Use this file to discover all available pages before exploring further. # Create site > Register a new site. The site must have a valid address and postcode. If a site with the same address already exists, a 409 error will be returned with the existing site ID. ## OpenAPI ````yaml POST /entities/site openapi: 3.1.0 info: title: Axle API Docs description: >- For full documentation please see our official docs at docs.axle.energy version: 1.4.6 servers: - url: https://api-sandbox.axle.energy security: [] tags: - name: 1. Authentication description: Authenticate yourself with the Axle API - name: 2. Meters description: Find key info about your sites - name: 3. Sites description: Register your sites with Axle; configure market participation - name: 4. Assets description: Register your assets with Axle - name: 5. Data description: Send asset metrics to Axle, for analysis and optimisation purposes - name: 6. Rewards description: >- Determine how much your users have earned by participating with Axle; allow balance withdrawal - name: 7. Validation description: Validate structured data against Axle's rules - name: 8. Examples description: Get example data for testing paths: /entities/site: post: tags: - 3. Sites summary: Create Site description: >- Register a new site. The site must have a valid address and postcode. If a site with the same address already exists, a 409 error will be returned with the existing site ID. operationId: create_site_entities_site_post requestBody: content: application/json: schema: $ref: '#/components/schemas/SiteRequest' required: true responses: '200': description: Successful Response content: application/json: schema: $ref: '#/components/schemas/SiteResponse' '400': description: Invalid request or site already exists '404': description: Referenced entity not found '409': description: Site with same address already exists '422': description: Unprocessable Content content: application/json: schema: $ref: '#/components/schemas/ErrorWithDetail' '500': description: Internal server error security: - OAuth2PasswordBearer: [] components: schemas: SiteRequest: properties: mpan: type: string title: Mpan description: Meter Point Administration Number postcode: type: string title: Postcode description: UK postcode for the site street_address: type: string title: Street Address description: Street address for the site email: type: string title: Email description: >- Email address for the site. Include to enable 2FA for payment withdrawals. gave_boundary_meter_consent_at: type: string format: date-time title: Gave Boundary Meter Consent At description: >- Timezone-aware ISO 8601 timestamp (e.g. '2026-01-01T12:34:56Z') indicating when the household gave consent for Axle to access readings from their boundary meter, if consent was given. type: object required: - mpan - postcode title: SiteRequest description: Request model for creating a new site. SiteResponse: properties: id: type: string format: uuid title: Id description: Axle's internal UUID for the site mpan: type: string title: Mpan description: Meter Point Administration Number for the site postcode: type: string title: Postcode description: UK postcode for the site address: type: string title: Address description: Full address for the site asset_ids: items: type: string format: uuid type: array title: Asset Ids description: List of asset IDs associated with this site default: [] markets: items: $ref: '#/components/schemas/MarketResponse' type: array uniqueItems: true description: Markets the site is participating in dispatch_methods: items: $ref: '#/components/schemas/DispatchMethodResponse' type: array uniqueItems: true description: Dispatch methods allowed for the site tariff: allOf: - $ref: '#/components/schemas/TariffResponse' title: Tariff description: Tariff information for the site gave_boundary_meter_consent_at: type: string format: date-time title: Gave Boundary Meter Consent At description: Timestamp when boundary meter consent was given type: object required: - id title: SiteResponse description: Response model for site information. ErrorWithDetail: properties: detail: type: string title: Detail type: object required: - detail title: ErrorWithDetail description: Standard error response with a detailed message. MarketResponse: type: string enum: - cm - dfs - dno - lcm - sffr - wholesale title: MarketResponse description: |- Market types available for participation. - CM: Capacity Market - DFS: Dynamic Frequency Service - DNO: Distribution Network Operator flexibility services - LCM: Local Capacity Market - SFFR: Static Firm Frequency Response - WHOLESALE: Wholesale energy market DispatchMethodResponse: type: string enum: - cm_infrequent_dispatch - full_asset_schedule_control - limited_pause - vpp_limited_control title: DispatchMethodResponse description: Axle propositions that a site can enrol into. TariffResponse: properties: tariff_type: allOf: - $ref: '#/components/schemas/TariffType' description: Type of tariff tariff_cheap_start_time: type: string format: time title: Tariff Cheap Start Time description: Start time for off-peak/cheap rate period tariff_cheap_end_time: type: string format: time title: Tariff Cheap End Time description: End time for off-peak/cheap rate period type: object title: TariffResponse description: Response model for tariff information. TariffType: type: string enum: - single_rate - dual_rate - dynamic - smart - unknown title: TariffType description: An enumeration. securitySchemes: OAuth2PasswordBearer: type: oauth2 flows: password: scopes: {} tokenUrl: auth/token-form ````