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A month with an electricity monitor

Right, the kettle is on for a morning brew and apparently our household is using 3.07 kilowatts. That will include the chest freezer in the garage, the refrigerator in the kitchen, the electric kettle, my laptop and wireless network, oh and a little device sitting on my desk right now that’s monitoring all those electrons as they speed through the mains supply cable.

electricity monitor

The monitor consists of two parts, a battery-powered broadcast unit that has a magnetic clamp that you wrap around the main electricity cable (no wiring necessarily) and a display that picks up the signal and tells you how many kW you’re using at any given time. It can also convert that into an equivalent of carbon tonnage, although that’s a more dubious metric given that the monitor doesn’t know how the electricity we’re using is made (renewables, fossils, whatever). You can also tap in your tariff and get it to tell you how much you’re spending.

When I first got the device, I ran around the house, switching lights and gadgets on and off just to see how much energy they were using (a lot, but not as much as the kettle!). Crucially, I also looked at what a difference it makes hard switching off TVs and PVRs compared to leaving them on standby (very little).

Now that the kettle has boiled and my wife has kindly furnished me with a steaming brew, the monitor tells me we’re currently (no pun intended) using approximately 1 kilowatt at a rough cost of 23 pence per hour and a carbon dioxide equivalent of 460 grams per hour.

Having just written about wind power elsewhere and how that costs about 5 cents per kilowatt hour I’m a little confused as to how my power supplier can be charging me ten times as much for the power as it costs to produce, but that’s capitalism for you…

Anyway, back to the monitor. We’ve been using it for about a month now and are averaging about 15 kWh per day (almost 6 kg of carbon dioxide per day), which is actually within the target I set us (for now) based on the average electricity consumption of a family of four. Of course, that average consumption assumes that both kids go out to school and that both parents go out to work, but we’re not an average family and probably spend quite a few more hours using electricity each day working in a home office than most people. So, I can feel ever so slightly smug.

10:10 campaign

However, I was also one of the first few to sign up for the 10:10 campaign, which means in 2010 we have to cut our energy consumption by 10% (at least) (gas and electricity!). So, I’m already replacing the last few of our incandescent lightbulbs with compact fluorescents and making sure that all our PCs are set to standby after a very short period of inactivity.

TVs and PVRs? Well, there’s little point in having a PVR if it’s not set to standby to record shows you want to see, but it could also be considered redundant because of BBC iPlayer and other channels signing up with Google to run full content on Youtube, so the PVRs might go soon. TVs can always be switched off fully without problems. Persuading the kids to switch off bedroom lights when they leave their rooms is a different matter…

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