Is ditching generators possible yet?

morpho
morpho Solar Expert Posts: 176 ✭✭✭
okay, so Maybe not totally ditch the genny. I am wondering, given the price of solar panels being so low, is it feasible now to quadruple my array and keep a small battery bank so I can cut way down on my generator use in winter?

basically I have observed that on a cloudy day I have about 5 amps coming in, not enough to charge the system. If the array is 4 times the size I would be charged, even on a cloudy day. 

If possible, is there a way to do it simply?


11.5 kw array  -  3 - midnite solar classic 200's   -  Magnum MS-PAE Inverter  -  Magnum ME-RC50 remote  -  ME-BMK batt-monitor  -  8 DEKA Solar GC15 230amp hour (48v) - Yamaha ef3000ise - 1 confused look on face

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Yes, you can over panel your array/controller, and in good weather, switch off some of the strings with a breaker in the combiner box.  In winter, turn all the panels on.   Well, that's what I'd do.  
    and in winter, I run the generator, I don't have space/permits to add more panels
    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 ,

  • morpho
    morpho Solar Expert Posts: 176 ✭✭✭
    This is sort of what I was thinking, but I was hoping there was a way to automatically have the system limit the incoming power from the array. I'd hate to have to be running like mad to hit the breakers in time if the sun comes out all of a sudden. I spend enough time babysitting the system. (My wife and I have not been on a vacation together since we went off grid...somebody has to always be here to make sure the panels are clear, the batteries are happy, etc) If I had to manually monitor the sun on a minute to minute basis I would never get to leave the house!

    11.5 kw array  -  3 - midnite solar classic 200's   -  Magnum MS-PAE Inverter  -  Magnum ME-RC50 remote  -  ME-BMK batt-monitor  -  8 DEKA Solar GC15 230amp hour (48v) - Yamaha ef3000ise - 1 confused look on face
  • morpho
    morpho Solar Expert Posts: 176 ✭✭✭
    Hey Mike, I see you have a Listeroid. I keep toying with getting one. If you had a choice between the lister clone and a kubota genset...which would you go for?
    11.5 kw array  -  3 - midnite solar classic 200's   -  Magnum MS-PAE Inverter  -  Magnum ME-RC50 remote  -  ME-BMK batt-monitor  -  8 DEKA Solar GC15 230amp hour (48v) - Yamaha ef3000ise - 1 confused look on face
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    The simple way is to get the Magnum 100A mppt and fill it up. You would have a system that has coms that all speak the same language.  The mppt will current limit at whatever the max your batteries are happy with, that you program. You can monitor the system with a web ap.

    I have been doing this for most all of my customers and if you live in a good location you can ditch the genset. I have not run one in a decade.

     There is no reason for offgrid squalor like you are describing. Fix the problems!  Good luck!
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭

    Hi Morpho,

    The FM60 CC will limit its output current,   but,  have read that that CC can be a bit slow in limiting its current.

    The FM 60 and FM80 CCs also have an input current Limit.   This is the total String Isc needs to be less than 80% of the rated maximum output current.  This Isc limit would be 48 A total Isc of all of the PV strings.

    The other  thing to watch for,  is,   that significant over PV-ing your MPPT CC,  is that this tends to cause the input voltage to the CC to rise when there is good sun,  and the CC  is not in an MPPT Mode.   This causes more heating in the CC,   and could possible causes damage to the CC if it happened to be slow in Limiting its output current.

    FWIW,   Vic

    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    morpho said:
    Hey Mike, I see you have a Listeroid. I keep toying with getting one. If you had a choice between the lister clone and a kubota genset...which would you go for?
    It's all manual and needs babysitting.  The kubota, I could start, and run for a couple hours unattended.

    And Listeroids are getting rare, not many were imported before the EPA banned imports.
    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 ,

  • bill von novak
    bill von novak Solar Expert Posts: 891 ✭✭✭✭
    morpho said:
    This is sort of what I was thinking, but I was hoping there was a way to automatically have the system limit the incoming power from the array. I'd hate to have to be running like mad to hit the breakers in time if the sun comes out all of a sudden. I spend enough time babysitting the system. (My wife and I have not been on a vacation together since we went off grid...somebody has to always be here to make sure the panels are clear, the batteries are happy, etc) If I had to manually monitor the sun on a minute to minute basis I would never get to leave the house!

    Pretty much every good MPPT charge controller out there will limit output current for you.
  • morpho
    morpho Solar Expert Posts: 176 ✭✭✭
    edited January 2019 #9
    Dave - 
    “off-grid squalor” Hahahaha that is the funniest thing I have seen in a while. Don’t tell my wife that! I have her convinced this is great. 

    I was reading the info about the magnum 100A controller and it says it handles a max of 6600 watts from the array. So I’m probably misunderstanding the details but at face value I would need two of them. That sucks!  ;-)
    thanks for the info. 

    Mike - 
    thanks. Somewhere deep down inside I know this is true about the listeroids but...but...they are so cool!

    Vic -
    Thanks for that information, interesting. 

    Bill -
    thanks for the info. 

    11.5 kw array  -  3 - midnite solar classic 200's   -  Magnum MS-PAE Inverter  -  Magnum ME-RC50 remote  -  ME-BMK batt-monitor  -  8 DEKA Solar GC15 230amp hour (48v) - Yamaha ef3000ise - 1 confused look on face
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Well in 16 years of living off grid, I haven't run a generator yet... so yes.

    I suspect I did shorten the life of my current forklift battery running it at 20-40%SOC for about 3 days about 4 years ago when we had 1 hour of direct sunlight in 13 days. but it's hanging in there. I am somewhat over paneled, and my winter use is minimal compared to summer  1-3 kWhs (mostly fridge) compared to 14-20 (running an air conditioner along with the household)
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • Raj174
    Raj174 Solar Expert Posts: 795 ✭✭✭✭
    @morpho
    The problem is the battery chemistry, lead acid can't take that kind of amperage, but Lithium can. A 200AH bank of 15 or 16 CALB SE200FI cells wired in series will take a max of 200 constant charging amps. They are about 15% more efficient than GC FLA's and would yield about 7kWh usable when fully charged, DOD 70%. 16 of these cells would be about $4000. I have been using a 200 AH bank like this for about 2 1/2 years now, and they are amazing to say the least. Some caveats, A BMS that will provide cell monitoring and high and low battery disconnect functions is a must. Attached a photo of my bank when first installed.

    Rick


    4480W PV, MNE175DR-TR, MN Classic 150, Outback Radian GS4048A, Mate3, 51.2V 360AH nominal LiFePO4, Kohler Pro 5.2E genset.
  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,730 ✭✭✭✭✭✭
    Morpho, I think you are missing the concept here.

    If you need more charging current in winter, you add the panels. In the rest of the year you turn-off strings, or controllers. It is a one time thing in fall.
     As long as the current limit is set for the battery you are fine. This is especially true for LA batteries as they are alot harder to damage compared to L-ions.

    This is my strategy for north of 40 :) It does not always work up there, and that is why a genset is still needed.
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net