Why are there two prices?

Because Britain has no single power exchange. APX and N2EX both run day-ahead and intraday markets and both report a volume-weighted index, and Elexon publishes each. Neither is more official than the other.

Can the price go negative?

Yes. When generation exceeds demand and cannot be turned down quickly, prices can clear below zero and generators pay to keep producing. The chart keeps the zero line visible for exactly that reason.

Yes. It comes from Elexon's BMRS market index feed, key-free. Nothing is invented or simulated, and if the source cannot be reached the saver reports that instead of drawing something plausible.

Does it cost anything or need an account?

No. Every screensaver here is free, runs in the browser and needs no sign-up. This one uses a public API that requires no key.

Two Exchanges, One Market Screensaver

The Two Exchanges, One Market screensaver plots the GB wholesale electricity price from both reporting exchanges — APX and N2EX — over two days, in pounds per megawatt-hour. It runs in the browser with nothing to install; press ESC to exit.

How the Two Exchanges, One Market screensaver works

The saver reads Elexon's BMRS market index feed, key-free.

No account and no key: the request goes straight from your browser, or from this site's own refreshed copy of the feed where the source does not permit browser access.

Values are drawn on a canvas that resizes with the window, so it works on a laptop or a wall display.

If the source is unreachable the saver says so on screen rather than showing stale numbers as though they were current.

A worked example

Two lines, one per exchange, each labelled with its current price. They usually track each other closely; the interesting moments are the gaps, when the two order books clear differently under stress. The footer states the current difference between them directly.

Settings & tips

Accent and Background recolour the display without changing the data.
Add it to a Multi-view grid to watch it alongside other live savers.
Press ESC at any time to leave fullscreen.

Frequently asked questions

Why are there two prices?: Because Britain has no single power exchange. APX and N2EX both run day-ahead and intraday markets and both report a volume-weighted index, and Elexon publishes each. Neither is more official than the other.
Can the price go negative?: Yes. When generation exceeds demand and cannot be turned down quickly, prices can clear below zero and generators pay to keep producing. The chart keeps the zero line visible for exactly that reason.
Is this real data?: Yes. It comes from Elexon's BMRS market index feed, key-free. Nothing is invented or simulated, and if the source cannot be reached the saver reports that instead of drawing something plausible.
Does it cost anything or need an account?: No. Every screensaver here is free, runs in the browser and needs no sign-up. This one uses a public API that requires no key.

← All Finance & Markets screensavers