Energy use

So I'm eagerly awaiting our first energy bill (...).

There are four of us sharing this house, three of us here most of the time and one just down during the week. We put in mostly energy saving lightbulbs (they are REALLY expensive here, compared to the UK!), but one housemate doesn't want mercury in their room, and the lounge and kitchen have special light fittings.

We cook using electricity, have an electric shower. All four of us have laptops, mobile phones, and so on. We don't watch TV at all.

It'll be interesting to see what our bill is like!

Anyway, in the meantime I've been using my electricity metering gizmo (plug it into a socket, then plug the item you want to check into it) to compare different washing machine cycles, how much it takes to charge and use a laptop, etc.

For the washing machine, it's not been a scientific study, as the weight of the load going in and the outside temperature has changed between washes. On average, for a 30 degree load on the "Eco" setting it used 0.4 kWh; change this to 40 degrees and it jumps to 0.75 kWh. Interestingly, changing to a Cotton "Super Quick" wash at 40 degrees only uses 0.55kWh.

Anyway, the scale of the change from 30 to 40 degrees is huge.

Using the tumble drier, which we've had to do on the rainy but warm days, is horrible. To dry on high for an hour is 1.45kWh; on low, about 0.95kWh. A really heavy load might need to be on for a couple of hours, though!!

For a medium load, the drying only took 40 minutes on high, which would be just under 1kWh, where the wash only takes 0.4kWh - drying in the sunshine is much better!

I have also been looking at my laptops. I have two, one which went travelling round the world with me (a netbook - 10 inch screen), and a full sized dual core one (15.4 inch screen). They have roughly the same battery life; the small one takes 0.03kWh to charge the battery from flat, and the large 0.05kWh.

When plugged in, running and charged, the small uses about 15W and the large 25W. When I last had a desktop PC, before leaving the UK, it would use more than 100W including the TFT monitor. So if you do need to upgrade, a laptop is probably more sensible, and a small laptop the best - despite what the manufacturers say, most people don't need a brand new laptop, rather one that only runs programs the user needs... but that's a whole different story.

Unfortunately there is no way for my meter to plug into either the shower or the cooker, so I have no idea how much energy they are using.

Electricity is about €0.20 per kWh here. So running my large laptop for 40 hours straight would cost about €0.20. Not so bad, except almost all of the electricity here is generated from non renewable resources...