---
title: "2-14 days ahead Transmission System Demand and surplus forecast (TSDFD) stream"
method: GET
path: "/datasets/TSDFD/stream"
tags: ["BMRS Datasets"]
---

# 2-14 days ahead Transmission System Demand and surplus forecast (TSDFD) stream

`GET /datasets/TSDFD/stream`

This endpoint provides the Transmission System Demand forecast. Data is available daily and will show values for the 2 to 14 days ahead.
Expressed as an average MW value for each settlement period. The Transmission System Demand forecast is based on historically metered generation output for Great Britain.
This value INCLUDES interconnector flows and demand from station transformers and pumped storage units.
            
Specific publish time filters may be supplied, otherwise this will retrieve the latest published forecast.
            
This endpoint has an optimised JSON payload and is aimed at frequent requests for the data.

## Query parameters

- `publishDateTimeFrom` string, date-time
- `publishDateTimeTo` string, date-time

## Response `200`

Data retrieved

- InsightsApiModelsResponsesDemandForecastDatasetRowsDemandForecastTransmissionDaily[]
  - `dataset` string, nullable
  - `publishTime` string, date-time
  - `forecastDate` string, date
  - `demand` integer, nullable

## Other responses

- `400` — Error with query parameters - see response for details
- `429` — Too many requests
- `500` — Server error - please try again later

---

[API](https://skmtc.net/elexon/apis/bmrs-insights.md) · [All operations](https://skmtc.net/elexon/apis/bmrs-insights/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/elexon/bmrs-insights/versions/d94e9edb295e/schema)