This question came up on a forum I’m on. It turns out it’s really quite easy to work out — this page covers pretty much all the details.
In addition to what’s there, it’s worth noting that the current Irish price for a kilowatt-hour under the ESB’s domestic rate is 12.73 cents per kWh, which works out as 14.41 cents per kWh once the 13.5% VAT is added in. So Irish users, pretend you live in New Hampshire (15 cents per kWh) to get realistic figures from the excellent cost calculator.
Using this, it looks like if I was to leave an 160W desktop computer on permanently in Ireland, I’d be spending 215 euros per year to power it. Wow, that’s pricey! My strategy of using low-noise, low-power hardware for home servers has paid off already, in that case. ;)
For what it’s worth, if you’re worrying about the power consumption of an NTL digital Pace Digital TV set-top box — if this Pace presentation is anything to go by, it appears the standby power consumption is on the order of 1-2 watts — about 2 euros per year. Grand.
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