[RE-wrenches] Switching to LiFePO4

Tue Sep 17 11:36:43 PDT 2024

It's expensive, but I second Jerry's recommendation. With three subarrays,
you should look at the Sol-Ark 15K with three MPPTs. The wiring is so clean with
this inverter in most circumstances, even on a retrofit. I am getting more and
more comfortable with EG4 LL batteries, mostly out of necessity as consumers
learn how cheap they are. But HomeGrid is also a great pairing, and I'm sure
others like Fortress, which I have not tried. 

If you do go the route of paralleling batteries and you don't have a stackable
battery system or EG4's cabinet with integrated bus bars, I have found the
Victron Lynx to be very handy up to 1000A. Over that, the Midnite 2000A combiner
box is big, but flexible and well designed.

I have resisted converting Outback systems to LiFePO due to the reported
problems mentioned by others. But in my situations, most are buying a BIG
battery and the inverter replacement cost becomes a smaller percentage of the
project cost.

Jason Szumlanski
Principal Solar Designer | Florida Solar Design Group
NABCEP Certified Solar Professional (PVIP)
Florida State Certified Solar Contractor CVC56956
Florida Certified Electrical Contractor EC13013208

On Tue, Sep 17, 2024 at 1:59 PM Jerry Shafer via RE-wrenches
<re-wrenches at lists.re-wrenches.org> wrote:

> Dave, 
> I would suggest stepping up to 48 nominal, fortress 18.5, battery 12 or 15 k
> solark inverter, re-wire the array to single or dual string, make the wiring
> in the home capable of 240, this usually requires main panel re-work and set
> up the monitoring. 
> Batteries are like replacement heart valves, never get startups or small
> manufacturers as so many disappear and now you are stuck.
> Fun times.
> 
> On Tue, Sep 17, 2024, 8:19 AM David Palumbo via RE-wrenches
> <re-wrenches at lists.re-wrenches.org [re-wrenches at lists.re-wrenches.org]> wrote:
> 
> > Wrenches,
> > 
> > 
> > I have a nice little rental house here in my off-grid neighborhood that
> > after 40 years is ready to transition to LiFePO4 batteries. 
> > I have no experience with any lithium home power storage batteries. I'm
> > looking for advice, so I can avoid mistakes as a rental house with battery
> > problems is quite the pain in the ass. The last tenant was my daughter so
> > life with older lead acids wasn't a huge issue, but now I want something I
> > won't have to enter the house to monitor and operate. I'll bullet what I
> > think I know and my questions.
> >  * The house has four 11-year-old Trojan Industrial IND 17-6 for 925 AH @
> >    24V that are amply sized for the houses loads.
> >  * It has a newer TriMetric meter that I was supposed to be able to set up
> >    for web access using their WIFI module, but I have had no success with
> >    being able to monitor battery state of charge remotely.
> >  * I really need something that will give me battery state of charge
> >    information without entering the house.
> >  * The system has a single OutBack VFX3624. PV array is 2.5kW. 
> >  * System also has a Iota 40A charger so charging with my 6 KW genset is
> >    typically in the 100Amp range with the OutBack and Iota.
> >  * We are in northern Vermont, so we rack up significant generator (NOT
> >    auto-start) run time in the winter months. 
> >  *  I'm looking at Eclipse LiFePO4 24V 200AH. Three of these will give me
> >    600AH @ 24V which is 65% of the rated Amp Hrs of the Trojan Industrials
> >    now in use. Is this enough?
> >  * My battery box can easily handle up to four of the Eclipse 24V 200AH
> >    batteries. I see that Backwoods recommends that only three of the Eclipse
> >    are connected with battery cables. If I opted for four (for 800AH) I
> >    would need to use a busbar.
> >  * Are there other distributors of Eclipse batteries other than Backwoods
> >    Solar that I should consider? I haven't used my dealer account with them
> >    for a number of years and I'm not sure that I'll get a good price from
> >    them.
> >  * What is the lead time for getting these batteries shipped out?
> >  * Are there other LiFePO4 batteries I should consider?
> >  * Is 600AH of LiFePO4's enough to replace 925AH of LA's?
> > 
> > Dave Palumbo
> > Retired from running Independent Power, but active in off-grid solar.
> > Hyde Park, VT
> > 802-371-8678 voice or text.
> > _______________________________________________
> > List sponsored by Redwood Alliance
> > 
> > Pay optional member dues here: http://re-wrenches.org
> > [http://re-wrenches.org]
> > 
> > List Address: RE-wrenches at lists.re-wrenches.org
> > [RE-wrenches at lists.re-wrenches.org]
> > 
> > Change listserver email address & settings:
> > http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
> > [http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org]
> > 
> > There are two list archives for searching. When one doesn't work, try the
> > other:
> > https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
> > [https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/]
> > http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
> > [http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org]
> > 
> > List rules & etiquette:
> > http://www.re-wrenches.org/etiquette.htm
> > [http://www.re-wrenches.org/etiquette.htm]
> > 
> > Check out or update participant bios:
> > http://www.members.re-wrenches.org [http://www.members.re-wrenches.org]
> 
> _______________________________________________
> List sponsored by Redwood Alliance
> 
> Pay optional member dues here: http://re-wrenches.org [http://re-wrenches.org]
> 
> List Address: RE-wrenches at lists.re-wrenches.org
> [RE-wrenches at lists.re-wrenches.org]
> 
> Change listserver email address & settings:
> http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
> [http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org]
> 
> There are two list archives for searching. When one doesn't work, try the
> other:
> https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/
> [https://www.mail-archive.com/re-wrenches@lists.re-wrenches.org/]
> http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
> [http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org]
> 
> List rules & etiquette:
> http://www.re-wrenches.org/etiquette.htm
> [http://www.re-wrenches.org/etiquette.htm]
> 
> Check out or update participant bios:
> http://www.members.re-wrenches.org [http://www.members.re-wrenches.org]
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20240917/6757289c/attachment.htm>