Overview

GB system price, demand and generation mix, plus Ireland's generation and demand — the top-of-desk snapshot for the UK and Ireland.

GB system price — —

GB net imbalance volume — —

GB demand now —

GB renewable share —

Ireland renewable share —

Ireland demand (approx.) — Derived from generation

📘Learning point: "System price" and "day-ahead price" aren't the same thing. The day-ahead price is agreed a day ahead based on forecasts; the system price reflects what actually happened after National Grid ESO balances the grid in real time — the two can diverge a lot when a weather forecast turns out to be wrong.

Primary analysis

Great BritainGB

Generation mix

—

Source: National Energy System Operator (NESO) Carbon Intensity API

IrelandIE

Generation mix

Source: Energy-Charts API (Fraunhofer ISE)

Power

GB system price and national demand, Ireland's approximate demand, plus 30-day trends.

Great Britain — price & demand

System Buy/Sell PriceGB

Balancing mechanism, per settlement period

—

System price —

Imbalance —

Source: Elexon Insights (BMRS) open data API

National DemandGB

Live electricity demand

—

Source: Elexon Insights (BMRS) open data API

📘Learning point: Great Britain's electricity day is split into 48 half-hour settlement periods. Generators and suppliers contract their output/consumption in advance for each one — the System Buy/Sell Price is what corrects any shortfall or surplus afterwards.

Ireland — approximate demand

Ireland doesn't have a direct public live-demand feed wired in here, so this is derived from total tracked generation instead.

30-day history

National DemandGB

30-day daily average

Source: Elexon Insights (BMRS) open data API, chunked into 7-day requests

Ireland — generation trend

30-day daily average

Source: Energy-Charts API (Fraunhofer ISE), 30-day range request

Renewables

Renewable share of the mix, trends, and how countries compare.

GB renewable share —

30-day avg renewable share — Great Britain

GB leading source — Largest slice of the current mix

📘Learning point: GB's renewable share is highly weather-dependent — a calm, cloudy day can see it fall below 20%, while a windy day can push it above 60%. That variability is why grid operators also need flexible, dispatchable sources like gas and storage.

Great BritainGB

Generation mix — 30-day trend

Source: NESO Carbon Intensity API, historical range endpoint

IrelandIE

Renewable share

Source: Energy-Charts API (Fraunhofer ISE), wind + solar + hydro share of latest sample

📘Learning point: GB and Ireland are both heavily wind-dependent, so their renewable shares swing a lot with the weather. Countries with more hydropower tend to be steadier by comparison — hydro output is far less weather-dependent and can be stored behind a dam and dispatched on demand.

Gas & LNG

European gas storage, flows and LNG send-out.

⛽

Not yet connected

Needs a free registration with GIE (AGSI+ storage / ALSI+ LNG data) and ENTSOG for pipeline flows. Both are free but require an account and API key — this is a task for whoever owns the site's data accounts, not something achievable with keyless public APIs alone.

📘Learning point: Europe holds strategic gas in underground storage ahead of winter — storage fill levels are one of the most closely watched indicators of winter price risk.

Weather

Wind, temperature and demand-driving weather across GB and Europe.

🌦️

Not yet connected

Open-Meteo's free tier covers this, but needs confirmation of usage limits for a production-traffic dashboard before wiring it in (commercial-tier check pending).

📘Learning point: Wind and solar forecasts are one of the biggest drivers of day-ahead price moves — a colder or calmer forecast than expected can send prices sharply higher.

Interconnectors

Cross-border electricity flows between GB and continental Europe.

🔌

Not yet connected

Needs an ENTSO-E Transparency Platform API token (free, requires registration by email) to pull cross-border physical flow data.

📘Learning point: Interconnectors let GB import cheaper European power (or export its own surplus) — flows typically run from the cheaper price zone toward the more expensive one.

Research & Sources

Where this data comes from, and its known limits.

Data sources

GB generation mix & history: National Energy System Operator (NESO) Carbon Intensity API.

GB demand, system price & imbalance volume: Elexon Insights (BMRS) open data API.

Ireland generation & demand (derived): Energy-Charts API (Fraunhofer ISE).

Day-ahead electricity prices aren't shown on this site for now: Great Britain isn't covered by the Energy-Charts price API at all, and Ireland's price zone is licensed "internal use only" — a future phase may add a licensed price source for one or both.

All sources are free and keyless except where a workspace is flagged "Setup needed" — those require a registered API key from ENTSO-E, ENTSOG or GIE.

Glossary

Key terms used across this site

Day-ahead price

The wholesale electricity price agreed a day before delivery, set by matching supply and demand bids for each hour or half-hour of the next day.

Settlement period

A 30-minute slice of the trading day. Great Britain's electricity market runs on 48 settlement periods per day, each settled separately.

System Buy/Sell Price

What National Grid ESO pays or charges to balance the grid in real time, after generators and suppliers' advance contracts turn out to be short or long.

Net Imbalance Volume (NIV)

The size of the shortfall (positive) or surplus (negative) between contracted and actual electricity in a settlement period.

Generation mix / fuel family

The breakdown of electricity output by source — gas, wind, nuclear, coal, hydro, solar and a catch-all "other" for smaller sources.

Renewable share

The percentage of electricity generation coming from wind, solar and hydro combined, at a given moment or averaged over time.

Interconnector

A cable that lets electricity flow between countries' grids, usually from the cheaper price zone toward the more expensive one.