We gave a mini update a little while back , but here is our first proper report into our energy usage in Sweden.

We set ourselves a quite tough goal when we moved here of 905 - 936 KWH per month . Even in Summer in the UK we didn't reach those sorts of levels.

 We've done a number of small things over the last few months to reduce the amount of energy we use without having to knit lentils.

• Only use electric lighting when we really need to
• Use the conservatory as a source of free heating for the house during the day time
• Use the conservatory as a source of free cooling during the evenings
• Bought an excellent energy efficient and variable temperature kettle
• Only boil enough water for the job
  
• Installed timer switches on devices that have a standby mode so they are genuinely turned off overnight
• Stopped running a server in the house 24 hours a day
• Made sure the freezer was kept filled to keep it efficient
• Not using a tumble drier

These little things, and there are many more, all make a difference. The new house having a heat pump for the hot water and central heating makes a difference too, as does the very energy efficient washing machine we have from the previous house owners, and the energy efficient dishwasher we brought with us from the UK.

Take one example above - the kettle.  

Water has a specific heat capacity of 4.1813 J g^-1 K^-1. To boil 1 litre of water from the tap takes 334 504 Joules of electricity. To take the 1 litre of water to 80ºC - the temperature you need for making coffee - only takes 250 878 Joules. That's a 25% saving! Boil only the 0.7 litres the coffee pot actually takes, and that goes down even further to 175 000 Joules - nearly half the original electricity usage. And that's just one rather simple seemingly trivial example.

1 KWH of electricity is 3 600 000 Joules. On a typical day we'll "boil" the kettle about 3 or 4 times. That's 427 328 860 Joules of electricity every year, or 118 KWH. By changing kettles and how we use it it comes down to 62 KWH a year, or a saving of about 4 days of electricity a year!

 The graph shows our usage over the last 2 months. The yellow line is our target. The blue our consumption to date rolled out to the full year, and the purple our usage in each individual meter reading taken to a full-year rate.

To put this in some context, we are using on average about 637 KWH per month at the moment. Our target was 936 KWH per month, and in the UK we were using 1811KWH per month over the last 11 years.