# Get live power data for a HEM system

Returns live power data for the HEM system. Power values (in watts) are derived from the most recent energy statistics, including raw measurements and calculated power flows between sources (solar, battery, grid) and destinations (home, battery, grid).

Endpoint: GET /hem_systems/{hem_system_id}/live_power
Version: 2.0
Security: oauth2

## Security:

  - `oauth2` (unknown)
    oauth2 scopes: home_energy:read

## Path parameters:

  - `hem_system_id` (string, required)
    The ID of the specific HEM system.

## Header parameters:

  - `EvEnergy-Version` (number)
    Specify the version of this endpoint to use.

## Response 200:

  - `200` (unknown)
    Returns live power data for the HEM system.

## Response 200 fields (application/json):

  - `sampled_at` (string, required)
    The timestamp of the energy statistics period.
    Example: 2024-06-15T12:00:00Z

  - `generation_watts` (integer | null, required)
    Solar generation power in watts. Null if inverter stats unavailable.
    Example: 3000

  - `consumption_watts` (integer | null, required)
    Household consumption power in watts. Null if any required stats unavailable.
    Example: 2400

  - `import_watts` (integer | null, required)
    Power imported from the grid in watts. Null if any required stats unavailable.
    Example: 1200

  - `export_watts` (integer | null, required)
    Power exported to the grid in watts. Null if any required stats unavailable.
    Example: 600

  - `charge_watts` (integer | null, required)
    Battery charging power in watts. Null if any required stats unavailable.
    Example: 1800

  - `discharge_watts` (integer | null, required)
    Battery discharging power in watts. Null if any required stats unavailable.
    Example: 900

  - `solar_to_home_watts` (integer | null, required)
    Derived power flow from solar to home in watts. Null if any required stats unavailable.
    Example: 1500

  - `solar_to_battery_watts` (integer | null, required)
    Derived power flow from solar to battery in watts. Null if any required stats unavailable.
    Example: 1000

  - `solar_to_grid_watts` (integer | null, required)
    Derived power flow from solar to grid in watts. Null if any required stats unavailable.
    Example: 500

  - `battery_to_home_watts` (integer | null, required)
    Derived power flow from battery to home in watts. Null if any required stats unavailable.
    Example: 700

  - `battery_to_grid_watts` (integer | null, required)
    Derived power flow from battery to grid in watts. Null if any required stats unavailable.
    Example: 200

  - `grid_to_home_watts` (integer | null, required)
    Derived power flow from grid to home in watts. Null if any required stats unavailable.
    Example: 200

  - `grid_to_battery_watts` (integer | null, required)
    Derived power flow from grid to battery in watts. Null if any required stats unavailable.
    Example: 100

  - `battery_state_of_charge_percentage` (integer | null, required)
    Battery state of charge as a percentage (0-100). Null if unavailable.
    Example: 82

## Response 200 headers (application/json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

  - `RetryAfter` (number)
    The number of seconds until this client's requests will not be rate limited.

## Response 400:

  - `400` (unknown)
    A problem with the request's parameters prevented it being fulfilled.

## Response 400 fields (application/problem+json):

  - `type` (string)
    Example: https://api.ev.energy/v2/problems/example-problem/

  - `status` (number)
    Example: 400

  - `title` (string, required)
    Example: Short description

  - `detail` (string, required)
    Example: Long, more specific description.

  - `instance` (string)
    Example: https://api.ev.energy/v2/users/user01HN2P75GBNFRJPCZJXEFVXH5E

  - `notification` (object)
    Something that the user should be informed about.

  - `notification.id` (string, required)
    Unique identifier for the Notification
    Example: notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.url` (string, required)
    Example: https://api.ev.energy/notifications/notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.message_id` (string, required)
    Internal identifier for this notification type. E.g. 'ERR0023'

  - `notification.category` (string, required)
    Category of this notification type
    Enum: "ACTIONABLE", "SERVICE", "RETRY", "MARKETING", "INTERNAL"

  - `notification.event_time` (string, required)
    The timestamp of the event described by this notification

  - `notification.short_text_title` (string, required)
    Short title for the notification

  - `notification.short_text_body` (string, required)
    Short description of the event being notified

  - `notification.detail_page_title` (string, required)
    Title of a help page giving more information about this notification

  - `notification.detail_page_body` (string, required)
    Text of a help page giving more information about this notification

  - `notification.external_link` (string | null, required)
    URL of a web page giving further information about this notification

  - `notification.external_button_label` (string, required)
    Text to be displayed on a button leading to the external_link location

  - `notification.read_at` (string)
    When the user examined the contents of this notification

  - `notification.resolved_at` (string)
    When the problem associated with this notification was resolved

## Response 400 headers (application/problem+json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

## Response 401:

  - `401` (unknown)
    You need to authorise requests to access this resource.

## Response 401 fields (application/problem+json):

  - `status` (number)
    Example: 401

  - `title` (string, required)
    Example: Unauthorized

  - `detail` (string, required)
    Example: Authentication credentials were not provided.

## Response 401 headers (application/problem+json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

  - `RetryAfter` (number)
    The number of seconds until this client's requests will not be rate limited.

## Response 403:

  - `403` (unknown)
    You do not have permission to perform this action.

## Response 403 fields (application/problem+json):

  - `status` (number)
    Example: 403

  - `title` (string, required)
    Example: Forbidden

  - `detail` (string, required)
    Example: You do not have permission to perform this action.

## Response 403 headers (application/problem+json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

  - `RetryAfter` (number)
    The number of seconds until this client's requests will not be rate limited.

## Response 404:

  - `404` (unknown)
    This resource either does not exist or the client is not authorized to access it.

## Response 404 fields (application/problem+json):

  - `status` (number)
    Example: 404

  - `title` (string, required)
    Example: Not found

  - `detail` (string, required)
    Example: Resource does not exist or cannot be accessed.

## Response 404 headers (application/problem+json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

  - `RetryAfter` (number)
    The number of seconds until this client's requests will not be rate limited.

## Response 406:

  - `406` (unknown)
    Could not satisfy the request Accept header.

## Response 406 fields (application/problem+json):

  - `status` (number)
    Example: 406

  - `title` (string, required)
    Example: Not Acceptable

  - `detail` (string, required)
    Example: Could not satisfy the request Accept header.

## Response 406 headers (application/problem+json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

  - `RetryAfter` (number)
    The number of seconds until this client's requests will not be rate limited.

## Response 429:

  - `429` (unknown)
    The client has exceeded its rate limit.

## Response 429 fields (application/problem+json):

  - `type` (string)
    Example: https://api.ev.energy/v2/problems/example-problem/

  - `status` (number)
    Example: 400

  - `title` (string, required)
    Example: Short description

  - `detail` (string, required)
    Example: Long, more specific description.

  - `instance` (string)
    Example: https://api.ev.energy/v2/users/user01HN2P75GBNFRJPCZJXEFVXH5E

  - `notification` (object)
    Something that the user should be informed about.

  - `notification.id` (string, required)
    Unique identifier for the Notification
    Example: notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.url` (string, required)
    Example: https://api.ev.energy/notifications/notf67O36PLTFDB57M0E5L33JZLGM0

  - `notification.message_id` (string, required)
    Internal identifier for this notification type. E.g. 'ERR0023'

  - `notification.category` (string, required)
    Category of this notification type
    Enum: "ACTIONABLE", "SERVICE", "RETRY", "MARKETING", "INTERNAL"

  - `notification.event_time` (string, required)
    The timestamp of the event described by this notification

  - `notification.short_text_title` (string, required)
    Short title for the notification

  - `notification.short_text_body` (string, required)
    Short description of the event being notified

  - `notification.detail_page_title` (string, required)
    Title of a help page giving more information about this notification

  - `notification.detail_page_body` (string, required)
    Text of a help page giving more information about this notification

  - `notification.external_link` (string | null, required)
    URL of a web page giving further information about this notification

  - `notification.external_button_label` (string, required)
    Text to be displayed on a button leading to the external_link location

  - `notification.read_at` (string)
    When the user examined the contents of this notification

  - `notification.resolved_at` (string)
    When the problem associated with this notification was resolved

## Response 429 headers (application/problem+json):

  - `EvEnergy-Version` (number)
    Indicates the version of the API that generated this response. If EvEnergy-Version was not specified in the request, this will be your OAuth application's default version.
    Enum: "2"

  - `Retry-After` (number)
    The number of seconds until this client's requests will not be rate limited.

  - `X-RateLimit-Limit` (number)
    The maximum number of requests that can be made to this endpoint per hour. Defaults to 1000 but may vary per client.

  - `X-RateLimit-Remaining` (number)
    The number of requests remaining until this client's rate limit is reached.

## Response 400 examples:

  - `Unsupported Version` (unknown)

## Response 429 examples:

  - `Example 1` (unknown)