navitron
 
Renewable Energy and Sustainability Forum
Welcome, Guest. Please login or register.

Login with username, password and session length
News: Anyone wishing to register as a new member on the forum is strongly recommended to use a "proper" email address - following recent spam/hack attempts on the forum, all security is set to "high", and "disposable" email addresses like Gmail, Yahoo and Hotmail tend to be viewed with suspicion, and the application rejected if there is any doubt whatsoever
 
Recent Articles: Navitron Partners With Solax to Help Create A More Sustainable Future | Navitron Calls for Increased Carbon Footprint Reduction In Light of Earth Overshoot Day | A plea from The David School - Issue 18
   Home   Help Search Login Register  
Pages: 1 2 [3] 4 5   Go Down
  Print  
Author Topic: Taking the plunge into battery storage  (Read 5819 times)
TedStriker
Newbie
*
Offline Offline

Posts: 37


Don't call me Shirley


« Reply #30 on: April 12, 2018, 07:34:43 PM »

I'm probably going to go for lead acid initially, as they can always be sold on for scrap value later. Last question for today (hopefully!), Forklift batteries are usually specified as Voltage and Ah so 24V 400Ah would give 9.6kWh on paper. Would you have to immediately halve this for 50% DoD or is that not the way it works?

Just about, you also have to consider the speed at which you discharge the battery. This is shown as a C rating, so C1 is a discharge over 1 hour, C5 over 5 etc. The traction batteries I track provide the Ah based on a C5 rating, if you draw power slower the battery is able to release more energy.

How about a couple of these to make it 48V to keep the current down?

https://www.ebay.co.uk/itm/123067616528?ViewItem=&item=123067616528

Along with a new Sofar ME3000SP inverter should do me a roughly 4/5kWh system (assuming a 50% DoD) for around £1k and leave the possibility to move to modular li-ion later.

Good plan?





« Last Edit: April 12, 2018, 07:38:43 PM by TedStriker » Logged

11 SunEdison SE-R285CMC-38 Panels
SAJ Sununo - TL3KA Inverter
Sofar ME2000SP charge controller
2x Pylontech US2000 Plus 2.4kWh battery packs
Solar iBoost+ (currently decommissioned due to incompatibility with Sofar)
RIT
Hero Member
*****
Offline Offline

Posts: 1700


« Reply #31 on: April 12, 2018, 08:15:13 PM »

Good Evening All,

I had always understood the optimal rate to be C20?

Regards

Richard

That is true, but traction/Forklift batteries are sold on the principal high current draws, rather than optimal draws, so the C5 rating is quoted. For the batteries I follow, the C20 Ah rating is about 30% greater than the C5 rating.
« Last Edit: April 12, 2018, 08:42:53 PM by RIT » Logged

2.4kW PV system, output can be seen at  - https://pvoutput.org/list.jsp?userid=49083

Why bother? - well, there is no planet B
TheFairway
Guest
« Reply #32 on: April 12, 2018, 08:47:20 PM »

Just about, you also have to consider the speed at which you discharge the battery. This is shown as a C rating, so C1 is a discharge over 1 hour, C5 over 5 etc. The traction batteries I track provide the Ah based on a C5 rating, if you draw power slower the battery is able to release more energy.
huh?

My understanding (from RC models) is that with C1 you can discharge at the mAh, which matches your full discharge in 1 hour, but with C5 you can draw at 5x the rate, so C5 could theoretically discharge in 12 minutes, not 5 hours as you say. Its a rating that indicates peak discharge rates as a proportion to the cell capacity, the higher the C number the more you can "abuse the battery".
Logged
A.L.
Hero Member
*****
Offline Offline

Posts: 876


« Reply #33 on: April 12, 2018, 10:16:59 PM »

hello,

Just about, you also have to consider the speed at which you discharge the battery. This is shown as a C rating, so C1 is a discharge over 1 hour, C5 over 5 etc. The traction batteries I track provide the Ah based on a C5 rating, if you draw power slower the battery is able to release more energy.
huh?
My understanding (from RC models) is that with C1 you can discharge at the mAh, which matches your full discharge in 1 hour, but with C5 you can draw at 5x the rate, so C5 could theoretically discharge in 12 minutes, not 5 hours as you say. Its a rating that indicates peak discharge rates as a proportion to the cell capacity, the higher the C number the more you can "abuse the battery".

Not quite, C5 is really C/5, to discharge in 12mins is to discharge at 5C

http://batteryuniversity.com/learn/article/what_is_the_c_rate
Logged
TedStriker
Newbie
*
Offline Offline

Posts: 37


Don't call me Shirley


« Reply #34 on: April 12, 2018, 11:26:48 PM »

Just to bring it back on topic  Smiley

What do you all think of this...

A couple of these in series to make it 48V to reach the nominal voltage of the Sofar inverter:

https://www.ebay.co.uk/itm/123067616528?ViewItem=&item=123067616528

Along with a new Sofar ME3000SP inverter, should do me a roughly 4/5kWh usable system (assuming a 50% DoD) for around £1k total and leave the possibility to move to modular li-ion later.

As for extra requirements, just battery-to-charger cables and a 100A isolator is all I can think of at the moment.

Good plan?

Could do with a go/no go soonish as going to sort it out on Friday if possible.

Cheers!


Logged

11 SunEdison SE-R285CMC-38 Panels
SAJ Sununo - TL3KA Inverter
Sofar ME2000SP charge controller
2x Pylontech US2000 Plus 2.4kWh battery packs
Solar iBoost+ (currently decommissioned due to incompatibility with Sofar)
billi
Global Moderator
Hero Member
*****
Offline Offline

Posts: 8827



WWW
« Reply #35 on: April 13, 2018, 01:41:41 AM »


Pv and battery is super simple and reliably , who makes the rules ?   That its made so complicated , every household roof should have one , and if its  not exactly matching the cost after 10 years   governments need to suport  a scheme  or tax  non renewable energy hgarder than its a no brainer to  bay back  upfront costs
« Last Edit: April 13, 2018, 11:43:32 AM by billi » Logged

1.6 kw and 2.4 kw   PV array  , Outback MX 60 and FM80 charge controller  ,24 volt 1600 AH Battery ,6 Kw Victron inverter charger, 1.1 kw high head hydro turbine as a back up generator , 5 kw woodburner, 36 solar tubes with 360 l water tank, 1.6 kw  windturbine
billi
Global Moderator
Hero Member
*****
Offline Offline

Posts: 8827



WWW
« Reply #36 on: April 13, 2018, 01:13:41 PM »

http://www.solarelectrix.de/home2_uk.html

Quote
The HOME 2 is basically the Home 2,4/4,8 without the internal batteries and the inverters. It makes the use of solar power easy and simple due to an internal battery charger and a discharge unit for the external microinverters. You just need upt to 3 microinverters and some batteries (24 - 48 Volt). The Home 2 doesn“t need a direct contact to a solar power system. Just a 230 Volt connection in your home and an infrared reader adapter for a smartmeter Easymeter Q3D if present is enough. The device will recognize if your solar field will feed energy in the grid at daytime and the internal battery charger will charge the external connected batteries. It will discharge the batteries at nighttime and will feed the required power (up to 750 Watt) via up to 3 small micro inverter in your homegrid. Some eCube Home can be linked if higher power values are be required. The eCube Home is a cost efficient alternative to other high price storage solutions. The installation is done in less than 5 minutes if the  Easymeter Q3d is already installed.
UVP 885,-

Logged

1.6 kw and 2.4 kw   PV array  , Outback MX 60 and FM80 charge controller  ,24 volt 1600 AH Battery ,6 Kw Victron inverter charger, 1.1 kw high head hydro turbine as a back up generator , 5 kw woodburner, 36 solar tubes with 360 l water tank, 1.6 kw  windturbine
TedStriker
Newbie
*
Offline Offline

Posts: 37


Don't call me Shirley


« Reply #37 on: April 14, 2018, 11:53:13 AM »

Just a quick one - I picked up the Sofar inverter/charger yesterday and am looking at placement of the CT sensors. I have both grid-in and PV-in in the consumer unit with enough space to fit the CT clamps around them but of course there are many other cables very nearby in there. Would that give bad results due to interference or is the fact that they are clamped around just one cable enough to stop interference? This is certainly the best location for the PV sensor as nowhere else in the installation are live and neutral separated physically.

I'm also assuming that this location 'logically' is fine for the clamps and that they don't need to be before the main or TGM meters?

Will be back end of next week before the batteries arrive so thinking of a temporary 'test' hookup with 4 spare car batteries I have in the garage and of course very low charge/discharge current limts and DoD. It appears that the inverter needs the battery input voltage to fire up which I suppose makes sense as if the logic circuits ran off the grid, they would die in a power cut situation and the emergency power supply wouldn't work.

Thanks.
Logged

11 SunEdison SE-R285CMC-38 Panels
SAJ Sununo - TL3KA Inverter
Sofar ME2000SP charge controller
2x Pylontech US2000 Plus 2.4kWh battery packs
Solar iBoost+ (currently decommissioned due to incompatibility with Sofar)
nowty
Hero Member
*****
Offline Offline

Posts: 595



« Reply #38 on: April 15, 2018, 05:40:47 PM »

Just a quick one - I picked up the Sofar inverter/charger yesterday and am looking at placement of the CT sensors. I have both grid-in and PV-in in the consumer unit with enough space to fit the CT clamps around them but of course there are many other cables very nearby in there. Would that give bad results due to interference or is the fact that they are clamped around just one cable enough to stop interference? This is certainly the best location for the PV sensor as nowhere else in the installation are live and neutral separated physically.

I'm also assuming that this location 'logically' is fine for the clamps and that they don't need to be before the main or TGM meters?

Interference should not be a problem and it does not matter whether the clamp goes before or after any of the meters.



PS - The Sofar inverter/charger is a nice bit of kit, probably the best value storage product on the market currently.

The other half is currently ironing and the Sofar is actively supplementing the solar with just the right amount from the battery to keep the import to zero.



And now the suns come out and the Sofar is charging the battery with the excess even though the other half's still ironing.
Logged

10kW of PV installed and 45+ MWh generated.
Usable battery storage of 50+ kWh.
Heat storage of 25+ kWh.
6kW Ground Source Heatpump.
200,000+ litres of water harvested from underground river.
A few cold frames and raised beds.
TedStriker
Newbie
*
Offline Offline

Posts: 37


Don't call me Shirley


« Reply #39 on: April 15, 2018, 07:04:45 PM »

Great to see a positive review, it looks like a great bit of kit to me too. Certainly for the money.

I have been playing around this weekend with some car batteries in series and got the system up and running, but have decided not to go down the lead acid route and to go straight for the modular Pylontech ES2000 Plus. Coming in at 24kg for 2.2kWh of usable capacity compares rather well with 220kg of lead acid for a similar rating. Cost is obviously higher but having been experimenting with just 4 car batteries has convinced me that I do not want to be dealing with half a tonne of fork lift batteries, gallons of sulphuric acid, monster cables, along with the grief I'd get for storing them on the patio next to the garden furniture!

Only decision I have to make now is do I buy one or two modules. I'm tempted by two partly for the extra capacity but also for the doubling of the charge/discharge current. Space wise I already have a half height 19 inch rack with about 10U spare so they can hide in there and no-one will be any the wiser. Just need to work out where I can hide the Sofar unit where it is out of the way but not too far from the CT clamp locations and a 16A supply from the CU. I already have a spare 32A MCB in the CU from a decommissioned electric shower so shouldn't be an issue re-purposing that with a smaller circuit breaker.

One thing that I can't see much detail of though is the real time and long term logging potential for the Sofar - ideally I'd like instant display plus something like that posted by Sprinter near the start of this thread for historical reports. Chances are the unit won't be in the most accessible location so the front panel will be of limited use.

https://www.navitron.org.uk/forum/index.php/topic,29465.msg334381.html#msg334381

You have no idea (or maybe you do) what a sense of satisfaction the following gave me after a long weekend of fabrication/trips to the tip/jump leads!




Any suggestions for monitoring?

Cheers,
Ted



« Last Edit: April 15, 2018, 07:06:47 PM by TedStriker » Logged

11 SunEdison SE-R285CMC-38 Panels
SAJ Sununo - TL3KA Inverter
Sofar ME2000SP charge controller
2x Pylontech US2000 Plus 2.4kWh battery packs
Solar iBoost+ (currently decommissioned due to incompatibility with Sofar)
nowty
Hero Member
*****
Offline Offline

Posts: 595



« Reply #40 on: April 15, 2018, 08:58:13 PM »

I have been playing around this weekend with some car batteries in series and got the system up and running, but have decided not to go down the lead acid route and to go straight for the modular Pylontech ES2000 Plus. Coming in at 24kg for 2.2kWh of usable capacity compares rather well with 220kg of lead acid for a similar rating. Cost is obviously higher but having been experimenting with just 4 car batteries has convinced me that I do not want to be dealing with half a tonne of fork lift batteries, gallons of sulphuric acid, monster cables, along with the grief I'd get for storing them on the patio next to the garden furniture!
You know it makes sense !, I have both but those Pylontech's are maintenance and worry free and may still cost no more than Lead Acid in the long run. sh*tfan


Only decision I have to make now is do I buy one or two modules. I'm tempted by two partly for the extra capacity but also for the doubling of the charge/discharge current. Space wise I already have a half height 19 inch rack with about 10U spare so they can hide in there and no-one will be any the wiser. Just need to work out where I can hide the Sofar unit where it is out of the way but not too far from the CT clamp locations and a 16A supply from the CU. I already have a spare 32A MCB in the CU from a decommissioned electric shower so shouldn't be an issue re-purposing that with a smaller circuit breaker.
Buy as many as you can afford, 2 at least, better with 3 so you can use the max charge / discharge facility of the unit. But I reckon no matter how many you buy, you WILL buy more as this games pretty addictive. ballspin


One thing that I can't see much detail of though is the real time and long term logging potential for the Sofar - ideally I'd like instant display plus something like that posted by Sprinter near the start of this thread for historical reports. Chances are the unit won't be in the most accessible location so the front panel will be of limited use.


Its got WiFi, you can get it connected (for free) to some server in China and get historic and real time info via an APP or website. But its not the easiest thing to set up. banghead


You have no idea (or maybe you do) what a sense of satisfaction the following gave me after a long weekend of fabrication/trips to the tip/jump leads!

Believe me, many on this forum do ! hysteria
Logged

10kW of PV installed and 45+ MWh generated.
Usable battery storage of 50+ kWh.
Heat storage of 25+ kWh.
6kW Ground Source Heatpump.
200,000+ litres of water harvested from underground river.
A few cold frames and raised beds.
Westie
Sr. Member
****
Offline Offline

Posts: 481


« Reply #41 on: April 16, 2018, 09:00:15 AM »

The SoFar unit does look promising, I just downloaded the manual and it's certainly written well compared to Growatt SP series.

Where did you source yours Nowty, and what was the pricing like, I've found new on Ebay for a grand but there's doesn't seem to b many distributors appointed yet. 

Sofar name their UK support as Infinity Innovations Ltd in Brdford but there's no web site setup.

By the way what do you reckon your storage cost per kWhr is at the moment?

Logged

4kwp south facing array  SMA 4000TL grid connected.  2x30tube Navitron solar thermal panels (east/west). Arada 5kw S/C WBS. 25000Ltr underground rain water tank. KTM E-Bike  Cool
Sprinter
Full Member
***
Offline Offline

Posts: 194


« Reply #42 on: April 16, 2018, 09:27:15 AM »

Only decision I have to make now is do I buy one or two modules. I'm tempted by two partly for the extra capacity but also for the doubling of the charge/discharge current. Space wise I already have a half height 19 inch rack with about 10U spare so they can hide in there and no-one will be any the wiser. Just need to work out where I can hide the Sofar unit where it is out of the way but not too far from the CT clamp locations and a 16A supply from the CU. I already have a spare 32A MCB in the CU from a decommissioned electric shower so shouldn't be an issue re-purposing that with a smaller circuit breaker.

Buy as many as you can afford, 2 at least, better with 3 so you can use the max charge / discharge facility of the unit. But I reckon no matter how many you buy, you WILL buy more as this games pretty addictive. ballspin

I could not agree more, buy as many as you can afford and leave room for when you can afford more. I bought the 4 kWh system as that's all that the finances could stretch too at the time i needed to make the order to get onto the trial i wanted, I was worried that 4 kWh just would not be enough and i was right as i have a high background load due to a 400 Liter fish tank and a vivarium, but i made sure the system was expandable and have already ordered the expansion to 6 kWh, i would like more but that's all i can have.

I am not sure you will double the charge/discharge rate though as that would be set by the inverter/charger not the batteries (or at least thats what i would have thought)


One thing that I can't see much detail of though is the real time and long term logging potential for the Sofar - ideally I'd like instant display plus something like that posted by Sprinter near the start of this thread for historical reports. Chances are the unit won't be in the most accessible location so the front panel will be of limited use.

Its got WiFi, you can get it connected (for free) to some server in China and get historic and real time info via an APP or website. But its not the easiest thing to set up. banghead

My chart was nothing to do with my solar or battery system, i put together an open source monitoring system as can be found at "https://openenergymonitor.org/"

Ideally you will need a raspbery pi, an RF board, an emoncms unit, an AC charger and a couple of CT Clamps, i think it was around about £140 - £150 but i had a spare pi sat around doing nothing.

I'm nosy and wanted to see what is going on in so much as whats our import, export Etc and should i put the washing machine on now or wait a bit longer.


Logged
nowty
Hero Member
*****
Offline Offline

Posts: 595



« Reply #43 on: April 16, 2018, 09:34:38 AM »

The SoFar unit does look promising, I just downloaded the manual and it's certainly written well compared to Growatt SP series.

Where did you source yours Nowty, and what was the pricing like, I've found new on Ebay for a grand but there's doesn't seem to b many distributors appointed yet. 

Sofar name their UK support as Infinity Innovations Ltd in Brdford but there's no web site setup.

By the way what do you reckon your storage cost per kWhr is at the moment?


Bought from HomeSwitch which has been referenced several times by various people. Circa £700 so cheapest I've seen.

The Pylontech LIFPO4 batteries are circa £333 per kWh but thats expensive compared with my re-used Growatt packs which I've sourced as low as £100 per kWh.
Logged

10kW of PV installed and 45+ MWh generated.
Usable battery storage of 50+ kWh.
Heat storage of 25+ kWh.
6kW Ground Source Heatpump.
200,000+ litres of water harvested from underground river.
A few cold frames and raised beds.
TedStriker
Newbie
*
Offline Offline

Posts: 37


Don't call me Shirley


« Reply #44 on: April 16, 2018, 09:42:27 AM »

Yes, homeswitch do the battery packs at £700 (ish) plus VAT and the charger unit at £560 ish plus VAT. They are supplying the ES2000 Plus batteries now, not the ES2000B that most people know. These give a better DoD and have a usable 2.2kWh each, which for £700 is pretty damn good. 10 year warranty on them too.

Scroll down for prices...

http://www.homeswitch.co.uk/sofar-ac-battery-storage

I just waiting for a quote then I'll head off and pick up 2 batteries. He keeps them in stock near Bradford.

So glad to not be dealing with masses of quite frankly scary lead acid batteries.
Logged

11 SunEdison SE-R285CMC-38 Panels
SAJ Sununo - TL3KA Inverter
Sofar ME2000SP charge controller
2x Pylontech US2000 Plus 2.4kWh battery packs
Solar iBoost+ (currently decommissioned due to incompatibility with Sofar)
Pages: 1 2 [3] 4 5   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.20 | SMF © 2013, Simple Machines
SMFAds for Free Forums
Simple Audio Video Embedder
Valid XHTML 1.0! Valid CSS!