2nd March 2012
We are into Spring and approaching the time of year when what I call ‘trimming’ occurs. Rather than supplementing heating the house requires the passive solar energy acts as a complete central heating solution. This means the number of weeks in the year when any conventional - that is to say carbon based - energy is required is trimmed down. During the Autumn the conventional heating in the house was left off for six weeks longer than it was in surrounding houses – this spring we are looking for a similar early switch off period.
The mild weather is helping – although the daytime temperature today is down to 9 degrees C again. What the system benefits from is a sun that is slightly higher in the sky and stays shining on the solar chimney for longer in the afternoon. Yesterday was not an exceptional day for solar energy but the intermittent sunshine saw a lot of heat stored in the wall behind the solar chimney. This meant warm air was still being fed into the house after the sun had set.
Trimming the portion of the year when heating is required has a significant impact on fuel bills as the conventional central heating system is not being run in the inefficient stop-start mode.
Have a good weekend and stay cosy.