Hi all, we had a 4.35kWh PV system installed along with a GIVENERGY GEN3 3.6 INVERTER and GIVENERGY GEN3 5.12KWH LIFEPO4 BATTERY.
We’re on the Octopus intelligent tariff for import and export, but so far that just means our battery sits idle at 100% most of the time.
We have also just had a SunAmp Thermino 150 ePlus phase change water battery installed and are now in the process of sorting out the solar key and Myenergi EDDI (single phase) diverter.
The hardware is more or less in hand, but we’re now trying to work out the best wiring pathways for the system and I’m hoping someone else will have installed this configuration or similar.
What we intend to do is have the SunAmp run directly from the battery so the battery and SunAmp aren’t competing for the PV outputs, but also so the diverter ensures that we are always using our “own” energy in the first instance and only going to the grid when the battery is low.
There are only two of us, so our hot water needs are very minimal so I doubt it will ever run the battery dry, but it’s winding me up a bit that Octopus leave the battery idle instead of using it stored energy (I have asked them to put it permanently on Eco mode, but they haven’t done it yet, will be escalating at the end of the month if it’s not sorted).
Happy for any experiences you can share, as this install is a first for all involved and even SunAmp don’t really have much experience with this type of configuration.
I assume you mean Octopus Intelligent Flux. On that tariff Octopus control the battery, charging it and discharging it when the grid needs it. I would anticipate it will get used more as we get into the winter as there is more strain on the grid and period when Octopus need your battery.
But to be honest this probably isn’t the best tariff to be on for the winter when you have low solar generation. There could be other tariffs that have lower import rates and will overall cost you less.
I don’t think getting an EDDI is the best value for you and I wouldn’t bother with it. Ignoring the purchase and installation costs you will make more money by letting your solar energy be exported - either 23p on Octopus Intelligent Flux or 15p on any of the other export tariffs.
This is not possible.
You have a hybrid inverter. It directly stores your DC solar generation in your battery. When you have house load (e.g. turn the kettle on) then your inverter would normally convert that stored DC power into AC and release it into the house. So there is no ‘direct access connection’’ to the battery, it only charges and discharges with solar and home load.
But you are on Octopus Intelligent Flux so the situation is different. Octopus control your battery not you. As you have said most of the time your battery sits idle and any solar generation is exported at 23p. If you turn the house load on then whatever cannot be supplied from your solar generation is imported from the grid, also at 23p. So whether you are importing or exporting its the same rate - you can think of the grid as being a giant infinite size battery.
this is a consequence of you signing up to Octopus Intelligent Flux, they control the battery, when it charges and when it discharges, They will not set it to Eco mode, it doesn’t work like that. But as I have explained, it doesn’t make any difference as your import and export rate are the same. In fact using the grid as a giant battery is actually more cost effective as you don’t incur the conversion losses of charging and discharging the battery which normally accumulate to 10-20%.
If you want to be able to use your battery when you want then you will have to choose a different tariff from OIF.
Thanks, this is helpful. I’ll go back to our solar guys to try to get a better understanding of why they recommended the eddi. Still keen to hear from anyone who has actually had a Sunamp or similar installed.