So are Surrettes worth the extra $$$?

stereoman405
stereoman405 Solar Expert Posts: 56 ✭✭✭✭
I had a deal on some nice telco AGM's that fell through so now I'm back to square one. :grr

I'm more of the 'pay once, cry once' kind of guy so I'm getting tempted by the allure of Surrette's cycling capacity and longevity despite the heavy price tag. My setup will have my bank in float for 99% of the time. But when an outage does occur it will be seeing 50% DOD. I'd like something that I can count on 8-12 years of life in this scenario. I've decided that checking SG every few months isn't a deal breaker. I just don't want something I have to hand hold too much.

My location will expose them the freezing temps for part of the year. But I do plan on having a grid tied float charger hooked up all the time.

What do you think? Surrettes worth it, or in this low cycling scenario would I be better off with Trojans or AGMs?

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: So are Surrettes worth the extra $$$?

    Just my opinion based on my own experience, but in your application the less expensive battery the better. The Surrettes' value would shine most where they were being used regularly, making good use of their cycling ability.

    For what it's worth, I've dragged Trojans down to 50% daily for half of a year in the past. Got six years out of them too. Pretty darn good batteries.

    AGM's are best used where gassing problems are a concern (enclosed space) or where self-discharge is an issue (batteries left without charging for long periods of time).

    Charged batteries don't freeze. The only warning here is that all deep cycles want to be cycled once in a while, monthly for example, or else they will suffer.

    Others' opinions/experiences may differ.
  • stereoman405
    stereoman405 Solar Expert Posts: 56 ✭✭✭✭
    Re: So are Surrettes worth the extra $$$?
    Just my opinion based on my own experience, but in your application the less expensive battery the better. The Surrettes' value would shine most where they were being used regularly, making good use of their cycling ability.

    For what it's worth, I've dragged Trojans down to 50% daily for half of a year in the past. Got six years out of them too. Pretty darn good batteries.

    AGM's are best used where gassing problems are a concern (enclosed space) or where self-discharge is an issue (batteries left without charging for long periods of time).

    Charged batteries don't freeze. The only warning here is that all deep cycles want to be cycled once in a while, monthly for example, or else they will suffer.

    Others' opinions/experiences may differ.

    Would a monthly equalize make up for the lack in cycling? Enough to 'stir' up the acid?

    Eventually when I get my solar in place I could set them up to get a little use. I could probably run a few lights or a small fridge off of them. But that might be 1-2 years out.

    Also what count as an 'enclosed space'? Would 4 batts in a 10' x 12' shed need venting?


    PS - Love the quote. Just watched that with my kids.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: So are Surrettes worth the extra $$$?

    You only have to equalize when the specific gravity between two or more cells shows a difference o more than 0.010 (others have different opinions on that as well). Equalizing isn't the same as drawing a battery down and recharging it. Ironically, maintaining a fixed Voltage is something deep cycles don't like (as opposed to car batteries, which prefer it).

    An enclosed space is also open to interpretation. It means anywhere that the gases from the batteries (hydrogen and oxygen released when charging) are trapped and present a potential hazard. There's quite a bit of debate about how much venting is needed for batteries. Both gases are lighter than air, so if there's venting of any kind it usually isn't a problem unless the area also has a source of ignition (such as an electrical spark - the biggest danger) or human habitation. An outside shed is probably drafty enough to vent.

    Just a hint; a "small 'frige" isn't terribly efficient but does use quite a bit of power. >You do actually want to drain the batteries down, maybe 50%, and then recharge them once a month. It is difficult to tell if you're drawing enough without some form of monitoring like a battery meter. The other choice would be checking the SG repeatedly and re-charging once it drops to 50% SOC. See the Battery FAQ:
    http://www.windsun.com/Batteries/Battery_FAQ.htm

    Note: my avatar is not a chicken! That is a pileated woodpecker, which is as big as a chicken. :D
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: So are Surrettes worth the extra $$$?

    The real question--what is the use? Would a smaller battery (possibly AGM) + backup genset (propane/natural gas/etc.) be a better bet?

    You may need to look for UPS type batteries rather than Deep Cycle--those AGM's you lost out on would have been nice for your application.

    Even then, the smaller AGM's don't (seem to) last that long in UPS type applications... It can be a significant cost if you end up having to replace them every 3-5 years--and remember, testing/monitoring is going to be critical... You don't wan to find your battery bank (or genset) is effectively DOA 6 years from now when you really need to use them.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • stereoman405
    stereoman405 Solar Expert Posts: 56 ✭✭✭✭
    Re: So are Surrettes worth the extra $$$?
    BB. wrote: »
    The real question--what is the use? Would a smaller battery (possibly AGM) + backup genset (propane/natural gas/etc.) be a better bet?

    You may need to look for UPS type batteries rather than Deep Cycle--those AGM's you lost out on would have been nice for your application.

    Even then, the smaller AGM's don't (seem to) last that long in UPS type applications... It can be a significant cost if you end up having to replace them every 3-5 years--and remember, testing/monitoring is going to be critical... You don't wan to find your battery bank (or genset) is effectively DOA 6 years from now when you really need to use them.

    -Bill

    Ya, definitely sucks missing out on those Telco AGM's....

    The hard thing here is that eventually I want to offload more and more of my 'on grid' to 'off grid'. I have the panels and am about ready to order the controller / breakers / etc, but due to some construction projects it will be a year or two before I can get the full array installed permanently. At least this way I have a stop gap in the meantime and can set a couple of the panels up temporarily if there is an extended outage. This would allow me to keep my genset at our primary residence and not have to haul it back and forth all the time.

    Sounds like going a 'cheaper' route might be best. I did just see that Surrette has some 'non-premium' L16's. The S-530. They are pretty comparable in price to a Trojan L16, but still seem to have some better cycling capability. I could get a 400AH bank for $700ish.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: So are Surrettes worth the extra $$$?

    Yea, probably start with a lower cost/smaller bank and get some experiences first... Most of us have killed our first bank.

    Best bang for the buck, spend time/money/knowledge on conservation first... Almost always a better place to spend your cash before solar anything.

    If you want, wire several circuits (some places you can get orange outlets). Wire them around the home (one near the fridge, another in your bead room for a small CFL lamp,perhaps a few overhead CFL/LED fixtures, etc.) so you can have your "backup circuits" already when you install your final backup system installed (solar/battery/genset).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: So are Surrettes worth the extra $$$?
    Sounds like going a 'cheaper' route might be best. I did just see that Surrette has some 'non-premium' L16's. The S-530. They are pretty comparable in price to a Trojan L16, but still seem to have some better cycling capability. I could get a 400AH bank for $700ish.

    How about 4 T105's if all you're looking for is around 400 Amp/hrs? They're 225 each, and much less expensive than the L16's. Especially if you can get some 'generic golf cart' batteries locally. That way, if for any reason they end up being useless by the time you get your panels in at least you won't be out so much money.