UK - Storage/Solar in detached garage

[swebbs1000v]

Hi,

Newbie here from UK, read a lot on this forum and YT but very much still learning!

My scenario is wanting to add DIY battery storage as stage 1, and solar as stage 2, installed in remote garage (45 metres away) but connected to house (+ grid tied at house only). House roof not suitable for solar but detached garage is. I've done a sketch as attached of the layout, everything existing except the orange bits. I want to be able to charge the battery storage at night (called Economy 7 in UK), and feed back to the house during the day. Stage 2 of the project will then be to add solar to the garage roof which has a suitable roof (house roof isn't an option).

Main question is this even possible, and what if anything do I need to add to control things within the house? I can add some more details like loadings etc if needed.

Any advice much appreciated, Thanks!

swebbs

 

[swebbs1000v]

... I guess it's basically this (from https://www.victronenergy.com/upload/documents/Brochure-Energy-Storage-EN_web.pdf) but may have some restrictions from the existing SWA cables?

But would appreciate your thoughts before I head off down the wrong route!

 

[ScottishBadger]

Batteries in a garage are not good, the colder climate severely limits their charging ability. I have a 5.2kWh battery pack in my workshop and it will only take about half charge in 4 hours of cheap electricity. There are also issues with the cable length potentially causing the supply inverter to overload and shut-down when a high load is applied within the house. I'm trying to resolve these exact issues right now and my cable run is 30m! Maybe take a look at a wall-hung all-in-one AC storage system such as the Puredrive Purestore 10kWh, I have one in the house and it works fine, no issues with cold restricting charge rates - all it needs is the occasional full discharge/recharge cycle to keep things "in line".

 

[SeaGal]

Hi,

Newbie here from UK, read a lot on this forum and YT but very much still learning!

My scenario is wanting to add DIY battery storage as stage 1, and solar as stage 2, installed in remote garage (45 metres away) but connected to house (+ grid tied at house only). House roof not suitable for solar but detached garage is. I've done a sketch as attached of the layout, everything existing except the orange bits. I want to be able to charge the battery storage at night (called Economy 7 in UK), and feed back to the house during the day. Stage 2 of the project will then be to add solar to the garage roof which has a suitable roof (house roof isn't an option).

Main question is this even possible, and what if anything do I need to add to control things within the house? I can add some more details like loadings etc if needed.

Any advice much appreciated, Thanks!

swebbs

All very do-able and very similar to the setup we have

From my experience (6kWp panels with a Solis RHI hybrid inverter and 14kWh of DIY batteries in garage 30m from house)...

You have identified the right issue - i.e. re SWA... I'd suggest:-

1) Keep the 6mm2 SWA for supply of garage load direct from consumer unit.

2) Install new SWA for the feed/supply to inverter from garage to house, but increase mm2 size to max possible. It's not just a question of current capacity, but also voltage drop/rise. Too much voltage rise will cause overvoltage at inverter if your grid voltage is on the high side . And too much drop when suppyling house loads or charging from grid is wasted energy heating the SWA. We have 8mm2 over 30m which is just enough - if doing it again, would increase that. There are tools online for calculating voltage drop, but if I were you I'd be looking at at least 10mm2 or preferably 12mm2, which you could also achieve with either two 6mm2 SWA or, if your garage is earthed with a TT configuration, you could parallel up cores in a 4 core 6mm2 SWA. Either way, power the garage from its own supply from the house, or you'll be pushing too many volts to your garage outlets.

3) Whilst installing SWA, also add some CAT5 cable to garage, unless already there - you will likely want connectivity there to control and monitor the system. BTW: Cat5e SWA is available and probably cheaper the regular Cat5 + ducting.

3) Add insulation (e.g PIR) around your DIY batteries and a little heater, temp controlled. Mine are a toasty 24 degrees this am when the garage is -1, all with just 15W heater ?.

Keep us updated!

Batteries in a garage are not good, the colder climate severely limits their charging ability. I have a 5.2kWh battery pack in my workshop and it will only take about half charge in 4 hours of cheap electricity.

I disagree - would much prefer to have batteries in safe location (away from living area), close to the inverter, with a little heater and insulation as I've discussed on many posts.

There are also issues with the cable length potentially causing the supply inverter to overload and shut-down when a high load is applied within the house. I'm trying to resolve these exact issues right now and my cable run is 30m!

Yes, voltage rise can be an issue as mentioned above. If you are still trying to resolve this, look at increasing the cable capacity from consumer unit to remote inverter.

 

[dmsims]

It depends

If you go Victron (and I suggest you do) - it's what we have then then are a number of options:

All the advice about cabling is sound but ESS (which runs under Venus on a Pi or Cerbo) allows you to limit the greed feed in by 10W increments

There is a separate dedicated AC out on the Multiplus

Be careful in your choice of BMS, ideally you want something that's supported in Venus e.g. JBD (not critical though!)

 

[dmsims]

Also can you give some idea of your peak/background use (for electricity consumption) and what size battery

 

[bruce_loco]

Hi
I am on a similar boat, posted my setup here:

UK setup - electrics from house to garage and back - help

Hi All This is what I plan to do as a setup. This design is only showing the AC setup, not panel connections, batteries, etc. I am facing some issues by which I don't want to do what is at the top as I don't have space to do this things practically or aesthetically. So at the top you see the...

diysolarforum.com

Can anyone give me some advice?
I have the MPP Solar PIP8048MAX, but I have two, so that might help with the load.