I will try and add my 2p worth...
Hi,
Had Solis inverter & panels installed last summer. Without battery as shortage & wondered if ROI OK without.
I would quite like to add battery now, partially for the UPS ability but also better use of the solar power.
Good plan, so much better with batteries. What was your original inverter model / size and how much PV do you have?
They did advise Solis 3.0kW 5G RAI Energy Storage AC Coupled & Pylontech us5000. So looking at that, am I allowed to DIY install, not too sure from the online manual whether need connection into the CU. I guess it must.
Yes it will need its own circuit. So unless you have an existing circuit that is dedicated and unused you will need part P compliance, which either means DIY and builing regs or a sparky to install or a friendly sparky to sign off. Obviously all work will need to be done to IET BS 7671 standards. But, can you not upgrade your existing Solis to a hybrid one? (see also below as you've since considered that).
I am assuming you have to use the supplied meter & cannot use the existing "emlite" I have that was put in with the original install.
I have a hybrid RHI Solis, not the RAI stand-alone... I _think_ from other postings on here, the RAI needs two CT clamps, one to measure solar feed from your existing inverter and one to measure grid import/export.
Also can you advise if the backup (UPS) output (I know only a few sockets etc) it automatically switched over.
ie. Can I have a computer plugged into this all the time & have power OK when the grid is on normal but if the grid power fails it will simply continue on?
Yes, but if there is no solar and your batteries run out, the inverter will power down and the backup load won't have any power (even if grid is up), so you will need enough battery to keep the inverter running.
& if grid power failure, will the solar charge the batteries, so hopefully keeping this UPS power running for longer.
Yes
Install, follow up question, I know previous contributer's were not sure on instal but have been advised that if I go the route of adding the AC, RAI extra inverter, needs DNO notification again so would have to go with the PV official installers. Does anyone know if can confirm this?
You will require DNO approval for adding to an existing G98 compliant installation. Hence you will need approval via the G99 process as G98 won't cover you for more than 16A potential grid export.
HOWEVER, you can do all the DNO stuff yourself (just specify 'self-install' where it asks for the installer details) - you don't need to have MCS certified installers to do that part.
Then had advise to swap the grid tied inverter for a hybrid, equipment bit more expensive but no DNO & thought easier install, makes sense.
Totall agree. Don't know why it would be more expensive as you don't need any additional wiring on the AC side of things. Plus you'll have a 1 year old Solis to sell on on ebay or whereever!
However had a quote from the guys, who were very good & value on original install bug said about £4600. (not sure if plus VAT)
Ouch... guess they _are_ busy then or just don't want the job
Bit confused, a Hybrid inverter & 4.8 Kwh battery is £2800inc VAT so £1800 install & I would have thought a quick'ish swap. Surely most of the cabling from the PC must be ready to go & even into the CU although not sure if would need to switch the meter but still that can't take too long.
Agree. Solis RHI is around £1100 incl VAT and you can get a better battery pack than Pylontech (e.g. fogstar 5.1kWh unit for £1400 incl VAT). So for your £4000 you can have hybrid inverter and 10.2kWh of battery and a second user inverter to sell on.
I know a bit of a whinge about costs.
ROI matters.
On this setup, from what I can glean from the manuals the Solis Hybrid inverter has almost identical connections to the non-hybrid inverter. Certainly on the mains/Grid size. Just a single plug so assume that goes to my CU the same as the existing grid tied one, same meter which does have a Imp & Exp written on the window etc.
My RHI has an Acrel meter, but still the same RS485 connection, so should be a simple swap.
My only thought & don't see why it would make any difference is the mains/grid cable going to the meter & CU on the existing grid tied inverter is really just one way at the moment, power from solar & inverter going INTO the house whereas the hybrid would take power from the grid to charge the batteries (when there is no Sun, or however it is programmed) Of course the cable does not care which way the electricity flows and must be big enough for the Amps required anyway.
That is correct. So unless you're increasing the size of the inverter, the cabling should already be sufficient - but obviously check that, I don't trust _any_ so-called professional installers.
So as far far as I can tell it would be a simple switch, unplug & plug the new one in.
So do I need the solar guys in? they want about £2k for this so making me think there has to be a lot more to it.
The "lot more to it"... is called their profit.
Does anyone know if this really is a like for like swap.
Can't answer that exactly as we don't know the model of your existing inverter, but should be pretty much like for like swap of inverter and grid meter in my mind ??
