Demystifying NESO: Grid Constraints, CCGT Maintenance, and the Kilowatts.io Dashboard

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In this episode, Nathan sits down with economist Ben Watts, the creator of the real-time energy dashboard at kilowatts.io. They explore the hidden "engine room" of the UK’s electricity system, the high-stakes market where power is traded in 30-minute blocks.

Ben explains why a single line on the map (the B6 Boundary) is costing consumers over £1 billion a year and how technology like heat pumps and EVs are moving from being "loads" to "assets" that help keep the grid balanced.

Key Jargon Buster: The Grid Boundaries

To help listeners follow the conversation, here is a quick guide to the "pinch points" Ben mentions:

• B6 Boundary: The most critical bottleneck in the UK. It runs along the Scottish-English border.
• B4 Boundary: A northern bottleneck separating the Scottish Highlands from the Central Belt.
• The "4.5 GW" Limit: The onshore overhead cables at B6 can securely handle about 4.5 GW. When combined with the Western HVDC subsea link (2.2 GW), the total limit is roughly 6.7 GW.
• Wind Curtailment: When there is more wind in Scotland than the B6 "pipes" can carry, NESO pays wind farms to stop generating while paying gas plants in the South to turn on.

Keywords & Themes

• kilowatts.io: Ben’s dashboard for visualising real-time grid data.
• NESO: The National Energy System Operator (the new name for the system operator in 2026).
• CCGT Maintenance: Why demineralised water is essential for the steam turbines in gas power plants.
• Flexibility Assets: Using heat pumps as "virtual power plants" to respond to grid signals at 50Hz.

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