Tuesday, 24 March 2009

Sunshine and gas bills

We have had 5 days of lovely sunshine. I have measured 29.9 degrees air temp. at input to the bathroom, and 29% relative humidity.

I trust that is good news, it means it will be drying out the fabric of our bathroom.

The solarventi unit is limited to 30 degrees C output. So that would explain the 29.9 degree reading at the vent in the bathroom ceiling.

The gas bill was unchanging on the year, well actually up 300 KWh on an annual consumption of 11000 KWh. Thats a 3% increase on last year. That is a mere 10 units on the meter. e.g. the gas meter reading was 370 units for the whole of last year, and 380 this. We are low users !!!

I confess that I am disappointed. Not because the solarventi hasn't delivered a small saving but because we replaced the old double glazing, fitted a bubble blanket in the loft for insulation and refreshed the draft-excluder around the front and back-door this time last year.

I guess it was a cold Feb. and the bill might have been much higher without those jobs done.

By the way, I reckon 300 KWh of energy, or 10 units on our gas meter, is probably the amount of energy we could expect to generate from the solarventi SV14 (heating our expanse upstairs) in a 12 month period. (2.5 KWh per day x 10 days per month x 12 months) Very approximately !!!