Recommendation for AGM's

bill von novak
bill von novak Solar Expert Posts: 891 ✭✭✭✭
Looking for 100-120 amp hour 12 volt AGM's for a load shedding/peak shaving demonstration system. Will be stored in a vented plastic battery box in a San Diego garage, so temps will tend to be higher rather than lower. Will be driving a GTFX3648. Anyone have a favorite?

Comments

  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Recommendation for AGM's

    Bill, is this just going to be a demo or will you have it 'performing' daily and doing real work?
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Recommendation for AGM's
    westbranch wrote: »
    Bill, is this just going to be a demo or will you have it 'performing' daily and doing real work?

    Demo, so periodic heavy cycling, with most of their time spent on float. It would in theory also be used during a blackout but we really don't get them around here.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Recommendation for AGM's

    In that case what about some AGM, GC2's , probably the cheapest route...
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Recommendation for AGM's

    Have you done the load-shaving calc, with the cost of the annual replacement of the batteries, against the savings off the electric bill ? Normally, simple grid-tie shaves a tier or two down and you get a good "passive" payback. Depends on how hard you are going to work the demo.

    I'd use 6V batteries in series (more jumpers) but when the inverter kicks in, and starts sucking power, you don't want the batteries sagging out after 10 minutes.
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Recommendation for AGM's

    If you're going to be using a GVFX3648 as it was meant to be used (grid-tied with full output capacity) you will need a lot more than 100 Amp hours of battery on it.

    And if you cut the array size down to 1kW to accommodate the small battery bank the inverter will consume 2.6% of the array capacity and 10% of the battery capacity on its own. Very inefficient with an undersized array.
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Recommendation for AGM's
    If you're going to be using a GVFX3648 as it was meant to be used (grid-tied with full output capacity) you will need a lot more than 100 Amp hours of battery on it.

    Bank is intentionally undersized. One of the questions to be answered by this experiment is "can you live with a much smaller battery pack if your goals are load shifting and you have a V2G source to supplant batteries when needed."
    And if you cut the array size down to 1kW to accommodate the small battery bank the inverter will consume 2.6% of the array capacity and 10% of the battery capacity on its own. Very inefficient with an undersized array.

    Array is ~10kW STC DC, but it's via string inverters on the main panel rather than the essentials panel.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Recommendation for AGM's

    Bill: V2G? definition?
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Recommendation for AGM's

    All battery charging supplied by the bi-direction AC connection of the GVFX. With grid present, batteries charged by grid. With grid absent, AC coupled GTI's supply charging and majority of power needs. GVFX acts as a 'sync signal' for the GTI's.

    If the power ratios are severely mismatched as they appear to be it will not work properly. But you don't have to take my word for it.
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Recommendation for AGM's
    westbranch wrote: »
    Bill: V2G? definition?

    Vehicle to grid. There's a lot of interest at my company on smart grid solutions for a number of reasons, and there's currently research money available for proof-of-concept projects for peak shifting and V2G peak shaving. This system will use a 3kW DC/DC converter that will take 220-370 volts from a vehicle and use it to supplant local storage.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Recommendation for AGM's

    So do you plan on charging from this oversized array? sure looks like it, and then back-feed from the EV to the grid... interesting.
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Recommendation for AGM's
    westbranch wrote: »
    So do you plan on charging from this oversized array?

    Not really; no need. The grid here is fairly reliable, and I already have the ability to run essentials off a generator. There's not much commercial interest in demonstrating either conventional solar hybrid PV systems or AC coupled hybrid PV systems. (Well, there's actually some interest, but they're available off-the-shelf here and plenty of proof-of-concepts already exist.)

    However if this proof-of-concept generates enough interest, the next step might be a built-from-scratch structure that incorporates solar PV, a fully capable hybrid battery system and an intelligent V2G connection. Again, the goal would be to demonstrate a system that can do load shifting (to better match peak generation) and load shaving (to deal with loss of generation from wind and/or solar unreliability.) There's a lot to that topic that other people in my group are working on.
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Recommendation for AGM's

    I can sure see the benefit of one massive load being satisfied by a fleet of EV's, ie during the early evening 'gamer demand', etc... 20 years ago, Brits were able to load shift simply by using the built in start timers on their dishwashers, clothes washers and dryers... DHW was remotely controlled by the utility. But that smacks of Big Brother now...
     
    KID #51B  4s 140W to 24V 900Ah C&D AGM
    CL#29032 FW 2126/ 2073/ 2133 175A E-Panel WBjr, 3 x 4s 140W to 24V 900Ah C&D AGM 
    Cotek ST1500W 24V Inverter,OmniCharge 3024,
    2 x Cisco WRT54GL i/c DD-WRT Rtr & Bridge,
    Eu3/2/1000i Gens, 1680W & E-Panel/WBjr to come, CL #647 asleep
    West Chilcotin, BC, Canada
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Recommendation for AGM's

    Come home from work in your electric car, plug it in to recharge. Go in and crank up the A/C, then turn on the TV. Fire up the electric oven to make dinner. Maybe take a shower with electrically heated water while you're waiting for dinner.

    Anyone see a problem with this?
  • kev1n69
    kev1n69 Registered Users Posts: 19
    Re: Recommendation for AGM's

    try this caribou

    come home with 80 % charge left in the car batts auto charger knows as you told it as you exited vehicle that you would not be going out later and draws power to feed your a.c. fridge,t.v. and stove alleviating some of the demand charger knows how much power you can feed for how long and stops suppling before any damage is done to the batt by that time you are done cooking the sun is down and a.c. demand has dropped off frig has cycled and cooled back down after being opened several times while cooking supper. t.v. is still on but led t.v. dont draw that much. charger kicks in and has car bat fully charged by 6.am ready for work and do it again the next day.
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Recommendation for AGM's

    and come the next day you lack enough power in the car to make it to work until the sun, if out, has charged the car up enough to get there.
  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    Re: Recommendation for AGM's
    Come home from work in your electric car, plug it in to recharge. Go in and crank up the A/C, then turn on the TV. Fire up the electric oven to make dinner. Maybe take a shower with electrically heated water while you're waiting for dinner. Anyone see a problem with this?

    Yeah, that would be a terrible idea from a grid loading standpoint.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: Recommendation for AGM's

    And if you have 80% charge left when you get home and if you keep the charger off while you're using power at peak rate so the battery can supply it, how low will it be when the off-peak rate begins and you can activate the charger? How full will it be by morning? Full enough?

    The basic problem with using a 'portable' battery is that it won't be parked in the garage during peak sun hours so that it can store up all that power to release it when the demand requires.

    Otherwise the time-shifting concept is a good one, even if the utilities don't think so. Let's face it; they are not interested in managing peak demands, only profiting by them.