We reluctantly gave up waiting for the arrival of micro CHP boilers and went ahead with the installation of a new gas condensing boiler in September 2008. This significantly improved our gas efficiency for space heating (by around 30%).
We've also dome some other things to make the heating system more efficient:
- Individual radiator thermostats (September 2005) so that we could save heat wastage in less used areas.
- A new central heating thermostat (October 2007) provided greater flexibility in terms of timing and temperature.
Reducing the standard living room temperature to 19°C which is comfortable for us but needs to be raised for some visitors (eg babies and those wearing tee-shirts in winter). Since writing this point, we've got used to 18°C!
- New, more efficient, radiators - no longer on outside walls.
Heat recovery extractor fans
We had a Vent Axia heat recovery extractor fan installed in the bathroom in July 2009. This provides ventilation and reduces condensation, without the heat loss of normal bathroom extractor fans. It has 2 settings, normal, which is on trickle rate all the time and uses 2 watts (18 kWh a year) and a boost setting eg for when someone takes a shower. We calculate that this will use slightly less energy than the old fan but the main purpose is to reduce heat loss in winter. An unexpected bonus is that it has made the bathroom ideal for drying washing in the winter when it won't dry outside. In February 2010, we had another one installed in the kitchen.
It was easy to switch the main ceiling lights to LED bulbs. We now have only LED bulbs in all our lighting. It was complicated to adapt some lamps and to get a thorough understanding of the various types of spotlights - lumens, colour rating etc.
Most of our kitchen gadgets are fairly old so we are caught in the dilemma of when is best to replace them – new low energy use models v the carbon cost of replacing things that ain't yet broke.
- electric kettle - our old kettle broke in January 2009 so we have replaced it with an Eco Kettle which makes it easy just to boil the amount of water needed. It probably won't make much difference to our electricity consumption as we were already quite conscious of not over filling the kettle.
- washing machine - the old machine (2001) kept going until early 2013 and we were sorry to lose it as it was hot and cold fill which meant we could use water heated by the solar thermal system. Washing at 30°C has produced no ill effects. We dry outside or in the bathroom where the heat exchange fan deals with moisture. Doing the washing overnight has the advantage of helping spread the electricity demand from the grid, ie when grid demand is at its lowest and not boosting the need for less efficient power stations to be switched on.
- fridge and freezer - replacing our 2001 vintage / not the highest efficiency rating fridge and freezer with an A++ fridge freeezer has reduced electricity consumption for refrigeration by more than 300 kWh per year.
cooking -we've tried to make our cooking more energy efficient by replacing an old microwave with an efficient combined microwave and convection oven and generally giving more thought to cooking and meal planning. Experiments with hay box style cooking have also been interesting -
We've used individually switchable distribution blocks and adaptor sockets to reduce the number of gadgets left on standby.
Since the installation of the condensing boiler and solar water heating, we've given more thought to our water heating. For one thing, we now have much of our summer water heating without using gas although we have enjoyed the challenge of thinking of the best timing for running the washing machine etc. Also, without the instant hot water we had with the old combi boiler, we've had to give thought to the subject of when and for how long to set the boiler to heat the water in the tank. In the second winter, we became more efficient at only heating the water we needed. We also got rid of the bath and now just take showers which reduces energy use for water heating and frees up space for drying washing in winter.