About WattWhen & the data
WattWhen reads Ireland’s live electricity grid and turns it into a simple answer: is now a good time to use power?
Where the data comes from
Every figure is live from the EirGrid Smart Grid Dashboard, the public data feed from Ireland’s transmission system operator, for the Republic of Ireland. We read the grid’s carbon intensity (grams of CO₂ per kilowatt-hour), how much of demand is being met by wind, total demand, and EirGrid’s demand and wind forecast for the rest of the day. It refreshes every 15 minutes; we re-read it every few minutes.
How we turn it into advice
Lower carbon intensity means the grid is running on cleaner, cheaper sources (mostly wind) rather than gas, so it’s a better time to use power. We flag the current level, compare it to today’s average, and use the wind-and-demand forecast to point out the greenest window still ahead.
An honest note on cost
Carbon intensity is grid-wide and real. Whether a green hour is also a cheap hour for you depends entirely on your electricity plan: on a flat rate the price never changes, so timing cuts your carbon but not your bill. The savings come from being on a smart, night-rate or EV tariff, which is why we help you check your plan.
What WattWhen is not
It’s an information tool, not energy or financial advice, and not affiliated with or endorsed by EirGrid. If the live feed is briefly unavailable, we show the last reading.
Who runs it
WattWhen is an independent project of ABL Media Group, an Irish media and data business.