I see lots of brochure materials stating 93% round trip efficiency for the All In One, and then talk on the forums of real life 80% round trip efficiency for gen1/2 inverters - and I guess the boxes take some power to run.
Anyone got any real-world round trip efficiency stats on the All in One please?(Assuming the firmware gets fixed). This efficiency figure is key when I look at my spreadsheet about whether the box pays back its installation cost or not - especially with power prices falling.
My first year of system use is almost up and these figures are based on the battery charge in [from both solar and grid] to battery charge out. I use this as round-trip efficiency and for me is 83%. There will no doubt be some variability with differing amounts of solar and grid charging, and some tolerance in the measurements; however it is 12 months worth.
There are still some software ‘features’ which I hope will be corrected shortly, causing unexpected sudden loss of charge.
I had a 13.5AIO installed in late November, looking at the GECloud page, helpfully battery charge = battery discharge
But, if I dip sample the usage charts, battery export is around 10-13% higher than the domestic load it’s covering - not very scientific unfortunately, but eyeballing the charts, looks like a fairly consistent difference between battery discharge and corresponding load.
Equally un-scientific, but once we’d moved to a tariff with 5p overnight rate where I could cheaply charge the battery, our daily electricity costs dropped from £4-£5 to <£1 as the AIO was usually enough to cover the full load all day and avoid peak rate energy consumption, often with excess that I could export at 12p.
Since we had the ASHP installed late January, I don’t have an excess to export, but most days we still manage to avoid peak rate importing.