Solar PV battery options

DC999

https://www.boards.ie/discussion/comment/120503991#Comment_120503991

I'd agree with bullit and look to see if there are ways to reduce the energy usage, certainly in the non heating months. Our house, as a comparision, uses ~225 a month (ex cooking, heating, EV). You're saying you use about 875 a month in summer. That's still close to 4 months of our usage. Granted it's a small house we we use a low amount. Don't mean to sound like I'm gloating, more giving a comparison. So more you cut back, the more you save.

championc

Maybe @big_red drop the temperature by one degree ? That's huge consumption. Not quite what you might expect from an A2 house.

Be very careful about a Hybrid inverter. Some need PV connected to work, I believe. A good option is a 5.5kW Sunsynk (which might get in under the new 25A limit ?) which can run with batteries only, and which can also run it's full rating if the grid is down.

Even get the most basic of PV and have high self use, and a size where you can DIY add to it.

munsterfan2

Hi big_red,

I went for these https://eu.nkon.nl/rechargeable/lifepo4/prismatisch/catl-prismatic-302ah-lifepo4-3-2v-b-grade.html from Netherlands, delivery within a week or 2. 140eur per cell ( 16 gives a 15kwh battery so 16sp3 would give 45kwh for 48 cells ( 6720 eur approx ( small 2% discount if paying by DD rather than cc )

Ruairi

oaklands

@munsterfan2 did you measure actual capacity vs quoted number on any or all cells?

bullit_dodger

Heating (as I understand it) isn't linear though. as in if you double the floor space, you wouldn't necessarily double the cost. The real answer is .... complicated. A lot to do with heat loss coefficients, type of heating (underfloor, radiators), etc. I understand some of the theory, but really you'd need an expert to have a look.

15K in electricity seems high though. Some really small changes there could reap very (very) significant reductions. Even simple things like checking when you are heating water. No sense in heating water at 1am, and leaving it sit there all night losing energy in the tank. Have the timer come on and heat it at 6am - those sort of things. You'd really be surprised at what you can save. Same deal with lights. If you have any of those Halogen 50w spots, you can bin those for starters and replace with 5W LEDs for the same brightness.

The reason why this is important is that you want to solve the right problem. If your house is 100% energy efficient today, then you can proceed with spec'ing a suitable solar / battery combo. But if it's not, then you'll be overspec'ing the solution.

Best €50 or you'll spend is on an energy meter to have a look at what your using and get a handle on each thing. Then you'll know (roughly) where/what is using that 15K/year

graememk

https://www.boards.ie/discussion/comment/120504710#Comment_120504710

🙈🙈🙈

yankinlk

15k = 40 units a day on average. Is it lumpy in winter and a little lower in summer?

I agree with above best move get a handle on what is consuming that 40 units. Is there a pump running constantly for example? Why?

Drop a degree or even 2 and see what happens. Can you live with that temp? If you are walking around in shorts in winter and thats what you like... Dont complain about the costs to achieve it!

munsterfan2

https://www.boards.ie/discussion/comment/120504434#Comment_120504434

Yes, tested one and got 306ah on the test. Have them installed and running perfectly with 300ah as capacity in Seplos. ( Had a very different experience with the CALB cells from PWOD / OYE - were supposed to be 200ah, ranged from 117 to 150 )

unkel

https://www.boards.ie/discussion/comment/120505915#Comment_120505915

Don't be a drama queen. 129 to 151 😂

unkel

https://www.boards.ie/discussion/comment/120504317#Comment_120504317

You have to put things into perspective. A typical household in Ireland uses 3000kWh of electricity per year. But that's with fossil fuel heating and with a fossil fuel car. That same house would use about 1500m3 of gas, which is 16000kWh of electricity equivalent! Add a single EV doing 25k km per year and there you have another 4500kWh per year. So that 3MWh is now 24MWh 😮

graememk

https://www.boards.ie/discussion/comment/120505968#Comment_120505968

If that heat load, of 16000kwh, was all heatpump (not accounting for cooking here)

With a high temp heatpump cop of 3, that's still 5.3MWh,

Or look at it another way, that's 3-4 500L fills of oil, for us out in the boomsticks

bullit_dodger

True unkel - you have to put things in perspective.

That said if I was consuming 15,000 kwhr and let's slap a figure of €0.30 on it as an average price, that's some €4,500/year. I'd be keen to know where that is going. What percentage is lights, heat, little Jonnies xBox - LOL. Becomes easier to fix if you know where/what is the actual problem.

slave1

Gotta ask, before looking to generating electricity at your entire house 23degrees 24/7, why? Why all night when only bedrooms occupied, this is way too high for bedrooms, I’d be like 14-16, same with hallways, unused rooms etc, then 23 itself, that’s very high, why not 18 ?

big_red

Thanks all for the great comments and feedback. I'll certainly do some more analysis on our consumption patterns- there's undoubtedly some low hanging savings. My [lazy] attitude has been to just over-spec the solution buts it a fair point, I should be more disciplined around our actual usage. I didn't mention earlier but we also have 2 x MVHR units running full time.

I have a sparks coming later this week to look at options to wire back to our CU, I'll also talk to him about getting some monitoring on our usage.

@munsterfan2 - thanks for the link to the batteries, I'll check those out. Can I ask what kit you have them paired with in terms or active balancer, BMS, inverter etc?

munsterfan2

https://www.boards.ie/discussion/comment/120513933#Comment_120513933

Sure,

Seplos BMS and Neey active balancer. My inverter is a solis which is working well. I have a raspberry pi hooked up to the BMS using Solarman https://github.com/byte4geek/SEPLOS_MQTT to monitor cells and report back to home assistant. Charging between 2 & 5 on 9c rate @ 50a, discharging at 0a until 8am ( as leaf tends to be charging ) and then as needed from 8:00am until 02:00am.

munsterfan2

Editing my last post - it's not solarman, but the seplos mqtt script which I use to get the BMS data https://github.com/byte4geek/SEPLOS_MQTT

randombar

Hi all, ordering the neey for my 16s2p set up

https://www.aliexpress.com/item/1005003125644284.html?spm=a2g0o.cart.0.0.d39238daXpASd2&mp=1

Just wondering if I need anything else with it?

Mr Q

https://www.boards.ie/discussion/comment/120519157#Comment_120519157

No, they come with everything needed. Just add ring terminals to suit your batteries.

Make sure you click shipping from Poland and not China.

DrPhilG

I just installed mine the other day.

jasgrif11

I managed to get a loan of a HMP4040 power supply. Basically, it has 4 inputs/outputs. I have 48 cells arriving early next month. I'm thinking of setting them up as 4 X 12 in parallel and top balancing them at 3.65V 10A at the same time. Alternatively, the power supply can work in parallel and do 40A. As anyone done something similar?

munsterfan2

https://www.boards.ie/discussion/comment/120519157#Comment_120519157

If you are monitoring with HomeAssistant an ESP32 board can monitor the neey https://www.amazon.co.uk/dp/B07VJ34N2Q?ref=ppx_yo2ov_dt_b_product_details&th=1 Cheap bit of kit and fun to play with.

jasgrif11

Does anyone have a wiring diagram and manual for the Neey Active Balancer?

unkel

https://www.boards.ie/discussion/comment/120524380#Comment_120524380

IIRC it's on the AliExpress website if you bought from one of the main suppliers. Pretty straight forward anyway, if you through up a picture here, we'll tell you what cells the balance wires should connect to

jasgrif11

https://www.boards.ie/discussion/comment/120179545#Comment_120179545

Here is my setup. Do i need to wire B01 to B24 and plus/minus?

graememk

https://www.boards.ie/discussion/comment/120524979#Comment_120524979

Ignore b17-24 you only have 16 cells.

B- to most negative(black)

B1-b16 to positive of each cell

And b+ (red) to the most positive, which will be the positive of cell 16.

DrPhilG

A successful day spent balancing batteries.

unkel

That's as close to perfection as it gets, @DrPhilG. Well done.

Care to share what you did balancing and what hardware you have, what size battery, what inverter, what BMS and I guess a 4A NEEEEYYYYYYY?

DrPhilG

https://www.boards.ie/discussion/comment/120544682#Comment_120544682

6kW Solis

20kWh LiFePo4 from OYE on AliExpress

ZEVA BMS

Neey balancer

Only got around to fitting the balancer the other week, it's been sat in the attic for about 3 months.

I was home yesterday due to the bank holiday so decided to bit the bullet and balance up. Charged fully overnight with the pack voltage set at 56v. Got to around this point.

Balanced to within 0.003v but I couldn't get it to increase as the charge kept getting throttled even when I increased the voltage in the bms to 57 and then 58v.

Eventually figured out that the inverter still had a limit set.

Battery overvoltage was set to 56.5v and the inverter will throttle the charge down once you're getting close to that. Increased that to 59v and it allowed me to push the charge up to the level I needed.

Once it tipped 58v the bms reset the SOC to 100% and that was the job done.

Currently down at about 33% as I'm squeezing a few units into the car before I go to work.

CramCycle

https://www.boards.ie/discussion/comment/120503991#Comment_120503991

Your house sounds similar to mine, I would say if you dropped the temp to 20 or 21 (lower if you can take it) and you will save enough money to pay for all the upgrades you plan within 5 years. The difference in cost for heating as you increase the temp is substantial IMO. We took 1/3 of our bills just by dropping 2 degrees in what was a B1 (now A2).

footfall789

Hi,

Have a PureDrive SOL-R16-5kw for my Solar Panels.

Could anybody tell me if it is a Lead Acid Battery or a Lithium Battery

Regards, Footfall789