Otter cottage energy use falls

Solar hot water and timer switches have slashed energy use in the cottage. This past winter has been our first chance to test our energy conservation measures in the cottage. It got its solar hot water in March 2010. And last autumn a couple of unseasonably energy-guzzling stays prompted us to get on and fit timer switches to the immersion top up and to the main heaters in Otter Cottage.

The switches mean the immersion heater turns itself off, and the room heaters stay on for two hours max before you have to make a conscious effort and actually get up and press a button to put them on again.

The timers are not to deprive guests of heat – you still have control over how warm the cottage is. But they do make it harder to leave everything on and go out all day, or to leave the heating burning all night. And the results are clear. (The arrow shows when the timers on room heaters were installed.)

The cottage still uses more energy than the lodges – adding switches hasn’t removed the need to heat it and guests still need hot water on cloudy days. But switches have cut out the ‘outliers’ with really high energy consumption.

Comparing the first quarter of this year (Jan to March) with the same period in 2010 (before the solar hot water was installed), average ‘per night’ energy use has fallen from 69.3 to 32 kWh (7 stays in 2010, 6 in 2011, Standard Deviation 23.3 and 13 respectively for 2010 and 2011). NB that’s a cold season figure, and it equals the cottage’s overall annual average from last year, so I’m hoping that will have fallen substantially too – when we get there.

Of course, there may have been other factors. December was cold, but this spring has been mild. And guests are more aware that we monitor energy use, possibly encouraging them to remember to switch off when things are not needed. But whatever the reason, the result is good.