There have been lots of discussions about the effectiveness and efficiency of an ASHP and so I am keeping basic records. I have my own electric meter on the supply to the ASHP so I know how much power has been used whether from the mains or the PV.

The result so far using the ASHP installed is 123 kWhs have been supplied to the ASHP from Jan 1 to Jan the 21^st to heat the building and hot water. As it is difficult to split the power used for hot water (and we have an immersion using the excess PV power on the hot water tank) from the power used for heating if we assume all of this power was used for heating that would equate to an average of roughly 2.6 Watts an hour per m2 of floor over the 20 days. Normal living with 2 people, showers, average 20C inside all day. Last night -2C outside some of the time. Used in the last 24 hours: 12kWh's.

Whilst we are happy with the results now being obtained, I would like to point out that the results were completely different when we installed the ASHP, when the very thick lagging was missing and we were using it like a boiler!  

Good luck with your endeavours.

M