Solar panels and battery - any real world reccomendations?

About 10mins from applying. Was down to 30% overnight so thought I'd do it now on a good day. Up to 65% charged. Annoying having the gen1, so slow to charge at 2.5kw
 
For those that know a lot more about this than me and hopefully some here have what I am inquiring about.

Pylontech US5000 I was recommended by solar+battery installer but everything I can find say they have a normal output of 2400w on draw but installer said that after speaking with manufacturer they are 4800 but that is peak short duration draw not sustained and im getting really frustrated with the whole battery situation delaying my install due to the whole batteries not VAT free unless you get them whilst installing panels blah blah blah.

I got a quote for 14x395 Panels, 3xUS5000 and 5kw inverter but I want batteries that will go up to 4-5kw normal draw.

I got ~16,000 for an install and wanted to get as much battery storage I could after getting minimum 5kw worth of panels on roof.
 
Last edited:
@alphaomega16 Looking at the data sheet it says the recommended continuos draw is 80A, max continuous draw is 100A, peak 1 is 120A for 15 minutes, and peak 2 is 200A for 15 seconds. This is all dependant on cell temperature being 10 to 40c.

That means one battery can supply 3840w at 80A, or 4800w at 100A & 48v

Now if you have three correctly wired in parallel, so they each supply the same current, and presuming the cables are correctly specced, that's 3 x 4800w = 14.4kW (14400w)

You could probably save a fortune by only speccing one battery, then adding more afterwards, they are straight forward to add when using Pylontech batteries, so check what the cost is from your installer, and what they are to but afterwards, your installers mark up may well wipe out the VAT saving.

There are other options like Fogstar Rack Batteries, UK supplied with 8 year warranty and cheaper and more powerful than Pylontech, just make sure the inverter manufacture doesn't exclude their use like Solis does (it only names a few compatible batteries).
 
Last edited:
alphaomega16 said:
For those that know a lot more about this than me and hopefully some here have what I am inquiring about.

Pylontech US5000 I was recommended by solar+battery installer but everything I can find say they have a normal output of 2400w on draw but installer said that after speaking with manufacturer they are 4800 but that is peak short duration draw not sustained and im getting really frustrated with the whole battery situation delaying my install due to the whole batteries not VAT free unless you get them whilst installing panels blah blah blah.

I got a quote for 14x395 Panels, 3xUS5000 and 5kw inverter but I want batteries that will go up to 4-5kw normal draw.

I got ~16,000 for an install and wanted to get as much battery storage I could after getting minimum 5kw worth of panels on roof.
Click to expand...
sounds about right on the pylon batteries. I have them and they will happily run a 3kwh oven kettle or air fryer ... but only because the demand is not long term , it's in spikes which the battery can manage.

put multiple high power devices on at once however and once you go over a little more than 2.4kw and the grid / panels have to supplement.

it is something we have learned to work around . we try not to put too many things on at once. can't always be helped when cooking however

that said..... that may be a setting in our inverter . the battery is set to charge and discharge at 50A. dunno if upping that would void the warranty on the battery
 
Last edited:
My Solis inverter had a long list of battery types you could use.

The battery type just sets some default values, like min/max voltage for easy setup. These can also be entered manually in the 'Other' battery profile.
 
My pylontech set up will easily power stuff long term at 4kwh like the hot tub. I have three us5000. It seems the inverter is the limiting point when combining solar and battery during the day. It tops out at just over 6kwh and then requires grid.

As a result we just ensure we don’t have hot tub and other appliances on at the same time.
 
My 3x Pylontech 3000Cs comfortably supply 4000w. Beyond that its solar/grid.
Your inverter will spec a limit on what it can handle on the battery side. My 5kw LuxPower hybrid inverter can manage 4kw/80a from the batteries only.
Even if you pull a bit from the grid when your consumption peaks the amount will be tiny for most.
 
Last edited:
There aren't many things that can or do continuously draw that high level of current if you look at actual usage. Dish Washer, washing machine, ovens all spiky loads (heat on, heat off, rinse repeat), kettle is high but short period, only thing I can think of that seems to draw a highish load almost constantly is tumble drier.

Plus if your drawing that sort of sustained load for a decent period your going to drain batteries very quickly so its probably going to make little difference to the overall cost your just going to draw some from grid earlier and batteries will last longer.

Unless you have well into double figures of kwh stored. My supposed 11kwh usable, (its acting as 9 but thats a diff story) can be drained surprisingly quickly in winter when you start turning loads of stuff on. It will charge/discharge at 5.5kwh and you can see the state of charge going down very rapidly if the house is busy.
Mine are inverter limited, each battery is supposed to be able to work at over 3kwh but the BMS and inverter limit that to 5.5kwh. I think the peak for short periods is 6.
Drawing 5.5kw means my 11kwh lasts 2 hours max, assuming its full at the start.
 
Last edited:
RE tumble drier.. next time you replace it get a heat pump. more expensive and take longer for sure but it sips power . our worst is a full towel load which takes maybe 4.5 hrs but it less than half the power of our old condenser and its peak use is really low so the battery can cope with it should it over run our cheap energy period. also means it can run directly off solar (no comment on why we use tumble drier on a sunny day ;) )
 
bigmike20vt said:
RE tumble drier.. next time you replace it get a heat pump. more expensive and take longer for sure but it sips power . our worst is a full towel load which takes maybe 4.5 hrs but it less than half the power of our old condenser and its peak use is really low so the battery can cope with it should it over run our cheap energy period. also means it can run directly off solar (no comment on why we use tumble drier on a sunny day ;) )
Click to expand...

I didn't buy heat pump although I probably would have if the "its only for occasional use we wont use it much" had been a truthful statement ;)

However that being said, the heat from the tumble ends up in the hall and upstairs anyway so its not lost. With the price of gas what it was last winter and a good chunk of my elec coming from go pricing I wasn't that worried about it using a lot.
Apart from days when she would insist on 2 loads and would empty the battery by mid afternoon.
Its a lot but its probably actually around 1.5kwh or so, so 2 hours or so per load is probably around 3kwh total. I'm going to meter it at some point.

I am actually seriously considering when the washer dies replacing with a washer drier and then would do the same to the tumble maybe a couple of years later.
So having 2x washer driers gets over the main issue with washer driers being reliability. I assume you can get heat pump washer driers for the dry cycle.
 
b0rn2sk8 said:
Washer dryers are usually not as good at both washing and drying.
Click to expand...
SBo said:
Yup seconded. And the drying capacity will be less than the washing capacity so you have to unload part anyway or do a small wash. Stay with seperate applicances.
Click to expand...

I know in regards both counts. But I would buy decent ones, some do get good reviews and would just do smaller washes when its going combo, hence the point of buying 2 ;)

What I didn't say was its also on the assumption that I remain on a cheap overnight elec deal. So I would be using them to do the full cycle during that period.
In the spring - autumn most of our washing gets hung outside.
 
You must log in or register to reply here.
Back
Top Bottom