INTERSTATE BATTERIES?

I guys.....I'm new to this group and new to solar.  I recently purchased a property off the grid with an 8KW Changfa run generator and a small solar to power an 1100 square foot house in Bagdad, Az.  The solar set up consists of an old 2012 Trace inverter, two C40 load controllers, 6-90 watt seimens panels, 3 Kyocera 120 panels and 16 T105 type of batteries.

Has anyone used the interstate L16 batteries (275 ahs) with any success?  They are very reasonable in comparison with the popular other ones @ $157 ea.

My plan is to trade the T105's for 12 of the L16's, swap the trace 2012 inverter for a
xantrex 4025, keep the two C40's and add three more of the Kyocera 120 panels for a total panel rate of 1260 watts.  I had also been considering using 16 of the L16 batteries but have been told it was extreme overkill.

Any help and suggestions would be appreciated.  Be gentle, I'm sensitive ....  :)


Dennis Webster
Bagdad, Arizona


Comments

  • System2
    System2 Posts: 6,290 admin
    Re: INTERSTATE BATTERIES?

    i've been using interstate l16's for 2.5 years, no problems yet.

    aren't they rated at 375ah?
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    dennis,
    you probably won't find the kc120s as they've been upgraded twice. they are now kc130s and are very popular.
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?
    Any help and suggestions would be appreciated

    Bagdad is located ~35 miles west of Prescott. Here’s a link to Prescott insolation data:

    http://rredc.nrel.gov/solar/old_data/nsrdb/redbook/sum2/23184.txt

    Assuming overall system efficiency of ~60% (w/ flooded cell batteries), your 1,290 W STC south-facing array tilted up at latitude (~35 degrees) will be able to produce an average of ~3.8 kWh /day in December.

    Bagdad, AZ gets hot in the summer (avg daily hi = 90 F or more June to Sept.), and monthly record highs from April to September range from 100 F to 114 F. Bagdad also gets cold in the winter, with average daily lows of 34 F in Dec. and Jan., and record lows of 8 F and 9 F in Dec. and Jan.

    These temperature extremes will result in relatively low array voltage in the summer and relatively high array voltage in the winter. This range can be a problem with systems incorporating a PWM controller like the C40, as the array's summer voltage may not be quite high enough to correctly charge and/or EQ the batteries, and the “extra” winter voltage, which when multiplied by current and time equals energy, will be wasted.

    The solution for this dilemma is an MPPT controller like the OutBack MX60. Specifically, you should build a “36 V array” to charge your 24 V battery bank. The MX60 will make the “translation”. The “36 V” array will produce enough voltage in the summer, and “extra” voltage produced in the winter will be converted to additional charge current, which could mean shorter generator run cycles.

    See: http://www.outbackpower.com/MX60.htm
    and: http://store.solar-electric.com/outpowmxmp.html

    The 36 V array could consist of four series strings wired in parallel. Two strings would be built from three each 12 V Siemens modules wired in series, a third string from the three KC-120’s wired in series, and the fourth string from the three new KC-130’s (replacements for the KC-120’s). The string outputs could be combined together using a PV combiner such as the Midnite Solar MNPV-6.

    See: http://www.midnitesolar.com/

    I’d consider an Outback VFX3524 inverter/charger instead of the 4024. The VFX3524 is a bit less expensive, and, with a Mate and a Hub, it can be networked with the MX60 to synchronize operations.

    See: http://www.outbackpower.com/OffGrid.htm
    And: http://store.solar-electric.com/outback.html

    A good rule of thumb is to size the PV array’s charge current at ~5% of the battery bank’s Ah capacity. Assuming 85% effective efficiency, your 1,290 W STC array will be good for ~37 A at ~29.6 V. Accordingly, a 24 V battery bank rated at ~740 Ah would be about right. That would be just eight L-16’s configured for 24 V. You might be able to handle 12 L-16’s, but 16 of ‘em would likely be a problem. Not buying the last four L-16’s will pay for the MX60, BTW.

    The Trojan L-16’s may seem like they’re more expensive than the Interstate models, but they now come with a seven year warranty, vs. what for the Interstates?

    See: http://www.trojanbattery.com/
    and: http://www.trojanbattery.com/Tech-Support/BatteryMaintenance.aspx
    and: http://www.interstatebatteries.com/www_2001/content/products/product_6volt.asp

    Don’t overlook VRLA (AGM or gel) batteries. Six size 8D models could be wired for 24 V x ~750 Ah. They require virtually no maintenance, and their energy efficiency (Wh out / Wh in) is ~90%, compared to ~80% for flooded-cell batteries. This translates into more useable energy from your system, which also could mean shorter generator run cycles.

    See: http://www.mkbattery.com/images/lagm.pdf
    and: http://www.concordebattery.com/xtender_main.php
    and: http://www.trojanbattery.com/Products/ProductSpec.aspx?Name=8D-AGM

    Finally, you’ll need a tidy and safe way to integrate all of this stuff together. Take a look at Midnite Solar’s E-panel for the Outback Inverters.

    See: http://www.midnitesolar.com/MidNite-Products.html
    And: http://www.midnitesolar.com/MidNite-Documents.html

    Now, was that gentle, or what?

    HTH,
    Jim / crewzer
  • backroad
    backroad Solar Expert Posts: 185 ✭✭
    Re: INTERSTATE BATTERIES?

    I did typo the AH on the L16 Interstate batteries and they are definitely 375AH.

    NAWS has explained to me that the 120's are no longer available, but I guess that's really no big deal. If it was, I quess I would just be out of luck huh? :)

    WOW Crewzer, all that will probably take me about the next year to weed out. It's tough to find out at age 55 that I'll Adult ADD. I'm going to have to get my printer out here to the property just to print all this and study it. I actually thought that my panels would put out a bunch more in the summer. Silly me, huh? I will definately look into the 36V, the MX60 and the Outback inverter.

    I would love to do the AGM batteries but I imagine they are a little out of my budget for now. I'm also having to do a complete remodel on the house as it's only 67 years old, has been moved three times in it's life (no it's not a mobile home), and it has not been lived in for the last three or so years which is really quite sad. I came in and serviced the solar batteries and had to add 7 gallons of water to the 16 of them. They are all (cept for one) currently showing about 75% which is much better than they were. BTW.....being that the batteries were already in trouble, I tried the old thing of adding aspirin to each one. Actually 3 or 4 to each. They were only showing about 50% before. Yes, they will be replaced shortly and given to a neighbor that's not so fortuneate.

    I will be doing most of my business with NAWS just because I like the way I was treated. Seem to be very nice and helpful people.
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    Dennis,

    I’m also 55… I’m starting thing that I’ve always been ADD, but I’m having trouble concentrating on the issue :wink: … Oh, well… my wife sometimes thinks I may have Aspergers… :roll:

    Getting a bit technical here, the PV modules will produce less power (Watts) in the summer when they’re hot, but likely more energy (Watt-hours) due to more hours of sunlight.

    Bad news about having to add so much water to the old batteries… low electrolyte means the plates were exposed, which in turn means they were oxidized, which means their capacity has been reduced.

    Adding aspiring to battery electrolyte forms ascetic acid. This may temporarily increase electrolyte’s specific gravity and increase the cell voltage, but it attacks the positive grid and active material, and so just causes even more damage in the long run.

    Good luck!
    Jim / crewzer
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    dennis,
    an upgrade to your system isn't a bad idea, but you may wish to take it a step at a time as you've got plenty to do. in doing your remodeling keep in mind possible things that you could do for the future of the system and as an example maybe some wiring that would be utilized for future solar applications. it is obvious that you need new batteries so that you could say is the first step you're taking on this solar remodeling journey no matter which battery you settle on. the next step is either the pvs or the controller. if you can swing both at the same time, that works. i think an mppt controller is in order for you as your system is big enough and is growing. true these controllers cost, but they do help you to wringout more from those expensive pvs. typically around 10% more, but it will vary at times. only mppt controllers have the ability to step voltages down from higher voltages pv systems so far, but not all mppt controllers have this feature. i cite as an example the sb2000. it only will work with the 12v pvs to 12v battery systems. that controller will utilize the excess voltage of the 12v pvs (which are roughly between 16.5v-17.6v) to increase the current somewhat. in any case you should use the battery temperature sensor for the controllers to properly track the batteries' true charge needs.
    some food for thought here is that when you remodel you will probably want to have a good deal of insulation, weather tight and insulative windows, as well as other weather tightenning items. now in this quest you are also confining the batteries in that same environment. standard leadacids will have to be vented or explosive hydrogen gas could build up inside your home. there are 2 ways to solve this. one way is to move them into a shed or other protective housing seperate from the house. another way is to provide a vent with the batteries in the home with their own air tight enclosure. there is one more way and that is to use the agm batteries as they really don't vent when charging properly. these batteries do cost more and are more efficient, but are safer to use indoors than the standard lead acid battery.
    there is some thought for you to use here in making a decision on how to pursue your system. as to the c40s, just sell them. you can do this here as an individual. if you are in the business of solar you aren't allowed to market your new stuff here.
  • System2
    System2 Posts: 6,290 admin
    Re: INTERSTATE BATTERIES?

    Why 24 volt, since you are buying a new inverter also? You can go 48 volts and deal with half of the amperage, use smaller wiring, and most are more satisfied with the higher voltage. The MPPT will still work with 48 volts, just have to have the voltage of the panels at up to 140 volts for the Outback.

    As for batteries I have been getting Hawker 6vf11 ($700 each new) a few years old from the phone company in Kansas City Missouri for $42. These are 100 AH @ the 8 hr rate. 800 AH @ 24 volts would cost $672. I can trade these in for the same weight batteries for only the price of a lunch for the battery guy. I would still wire these as 48 volts however. These are AGM batteries and are of the highest quality. They have been used in nuclear plants and places where the highest quality is required. The phone company gets rid of them well before their 12 year design life is up and are kept in a float condition. Look them up and see what a great battery they really are. Can't beat the price either.

    Skip
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?
    The MPPT will still work with 48 volts, just have to have the voltage of the panels at up to 140 volts for the Outback.

    Allowing for MX60 limitations, battery charging requirements and environmental factors, the ideal nominal array voltage for a 48 V battery bank is "60 V", or five "12 V" modules wired in series. That'll be tough to do with the 12 module array Dennis has planned.

    48 V systems do indeed have their benefits. However, considering his location, environment, planned array configuration, single inverter, and likely relatively small loads, a 24 V inverter will work just fine.

    I recommend caution when citing the MX' 140 V spec. It's a valid number, but it applies to an array's temperature-corrected Voc (i.e., six "12 V" modules wired in series in a cold environment) and not to an array's nominal operating voltage. The MX60's practical cold-environment voltage limit for five "12V" modules wired in series is ~87 Vmp STC.

    niel's made a good point about venting flooded-cell batteries. Another nice feature of the MX60 controller is that its 12 V AUX output can be user-programmed to activate/deactivate a small 12 V vent fan at a user-selected voltage (i.e., 28.8 V for a 24 V battery system).

    See this link for a popular vent fan suggestion: http://www.solarseller.com/battery_box_power_vent_by_zephyr_industries.htm

    HTH,
    Jim / crewzer
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    niel,

    I don't understand your last point... :?

    Thx,
    Jim / crewzer
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    never mind jim as i misread him, so i deleted my post. sorry about the corn fussion. :lol:
  • backroad
    backroad Solar Expert Posts: 185 ✭✭
    Re: INTERSTATE BATTERIES?

    I do plan on taking a step at at time, but I'm afaid the first one is a big-un..........

    All of my batteries, panels, controllers and inverter are located in a shed with the Changafa run generator. It's located about 75 feet from the house. The batteries are not contained, but sit on a bench in the open/venter shed.

    The plans for the house are on track with solar stuff. Lot's of insulation and new dual pane windows with tint. I'm not sure yet, whether I'm going to run some items with 12 volt or 24 volt. Some of these are a water pressure pump and solar chill evaporative coolers. They can be had in either voltage.

    I do plan on the battery replacement, adding the 3 Kyocera 130 panels and a larger inverter all at the same time.

    I've been doing a little reading on the MX60. Correct me if i'm wrong, but it appears that I may be able to use three unmatched type of panels with the one controller. That would of course eliminate the two Trace C40's.

    Due to finances, I'm probably not going to be able to do too much more for a while. Just have to be sure and do enough and spend it wisely.
  • backroad
    backroad Solar Expert Posts: 185 ✭✭
    Re: INTERSTATE BATTERIES?

    I just thought I'd post an update to my upgrades and couldn't have done it without your help.

    I did end up with the 3524 Outback inverter and the MX60 controller. They were pretty much a no-brainer decision. However, the battery thing was another story, but the Interstate distributor made up my mind for me. He was out of stock and told me about 4 weeks to deliver, but I could special order them which would tack on almost $800 in freight. Nope.....that definitely would NOT work. While I was at NAWS last Friday I brought home 12 of their Crown L16 Batteries with 395ah rating. Not the cheapest thing, but I'm comfortable with the decision, except for my back unloading them.

    Anyone want to come out to Bagdad, Arizona and help me installs this mess?

    Dennis in Bagdad.......
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    Sounds like you're making progress... I'd love to help, but I only accept payment in the multiple denominations of cold beverages made from water, barley, hops and yeast... :wink:

    Good luck, and I hope you'll keep us posted on the upgrade results!
    Jim / crewzer
  • backroad
    backroad Solar Expert Posts: 185 ✭✭
    Re: INTERSTATE BATTERIES?

    I don't mean to come off sounding like a lush, but there's always Amber Bock in the refrigerator. It only takes two to make me silly. There's also a 105 quart ice chest just waiting to be filled with the preferred adult beverage, even if you're from Virginia.

    My son's an electrician and I was planning on handing the install over to him, but he's currently flat on his back with lots of pain there. Oh well, back to the ol' instruction pages when time allows.

    The Outback stuff really does look sexy...............

    Dennis from Bagdad.................
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    Hmmmm... only ~2,000 miles to some "free" beer... I'll have to think about that... 8-) :lol::wink:

    I hope your son recovers soon, and good luck with your project!
    Jim / crewzer
  • Mangas
    Mangas Solar Expert Posts: 547 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    Thanks Jim.  Didn't realize the Trojans were warrantied for 7 years.  Hope that applies to mine installed early last year.

    My plan is to replace them in 9 - 10 years which I understand is the probable life if maintained properly.

    Learning a lot on this site.
    Ranch Off Grid System & Custom Home: 2 x pair stacked Schneider XW 5548+ Plus inverters (4), 2 x Schneider MPPT 80-600 Charge Controllers, 2 Xanbus AGS Generator Start and Air Extraction System Controllers, 64 Trojan L16 REB 6v 375 AH Flooded Cel Batteries w/Water Miser Caps, 44 x 185 Sharp Solar Panels, Cummins Onan RS20 KW Propane Water Cooled Genset, ICF Custom House Construction, all appliances, Central A/C, 2 x High Efficiency Variable Speed three ton Central A/C 220v compressors, 2 x Propane furnaces, 2 x Variable Speed Air Handlers, 2 x HD WiFi HVAC Zoned System Controllers
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: INTERSTATE BATTERIES?

    Mangas,

    Always glad to help where I can. Trojan's new warranty on "...any battery used in solar or renewable energy applications..." was effective September 1, 2006.

    Regards,
    Jim / crewzer