Part of that calculation involved going around all the power adapters and appliances we use every day, reading or calculating their wattages, and making an educated guess for those that didn't have enough information. But some of the wattages seemed ridiculously high (440W PC?? 200W modem?? Ridiculous!!).
So for the last few weeks, I've been braving the critters in the dank under the stairs, shining my mobile phone light into Edesur's power meter cabinet for our apartment, and laboriously noting down our kWh each day.
It turns out that the 10kWh per day that I had calculated is more than double what we're actually using. So you can't trust what it has printed on the adapter! Is that maybe some kind of worst-case thing? Or what it uses if you plug it into a 110V North American socket? Dunno.
For the first half, I carelessly left the PC on all night, and for the second, I diligently shut it down. But the wiggly lines are not appreciably lower on the right, so my conclusion is that this a waste of effort. The peaks of consumption were the girls' bath days, and when we ran a fan heater for half an hour or so in the bathroom so they won't turn blue (getting chilly here now).
Our average is actually 4.4kWh per day, and the peak on the longest-bath day was 6.5kWh.
So going back to my solar panel calculations, we would need 14 panels to cover an average day, or 20 to cover the peak.
14 panels isn't so bad - I reckon I already know where we would put 12 panels. And if I can grow my money-moustache a bit, and cut down our consumption, we might be able to get away with fewer.
So all is not lost!
