Shed

97TJ
97TJ Solar Expert Posts: 68 ✭✭
Located in Northern Michigan we get generally mild summers but some pretty cold winters. Is there any disadvantage to putting all of my solar components in a shed with the panels mounted on top of it? All of the runs could be kept short then I could run 12 gauge wire from the shed to the cabin which would be about 20 feet away.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Shed

    Depends--Will you be turning the inverter/battery power on and off (need remote switching?). Batteries below freezing have less capacity while cold--Shed insulated vs warm cabin/system not used in winter?

    If you have a generator/fuel supply-storage in shed--A fire in the generator shed can take out your battery bank and solar array.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Shed

    What you're thinking about is what I did in 2007. But being near the ocean, I suspect our temperature range is less than yours. That said, we do have -20c temps here, and with my batteries insulated for Winter (which I skipped the last 2 years) their temp seldom drops below 0C.
    I built the shed especially for this and one of the great beauties of the settup is that I located the panel rack on the South wall, hinged at the top, up next to the roof. In Winter, with the sun low in the sky, I drop then down to the vertical position, no snow collects on them, and the light reflected off the snow adds to the normal sunlight, really increasing output. Then come Spring, the panels are tilted up from the bottom for best Summer power harvest. Another advantage is that if there were some unfortunate happening that burned the house, my solar system would be spared. Likewise the other way around. Inverters and all are in the shed and only the 120 VAC is fed underground to the house. Very happy with it.
  • 97TJ
    97TJ Solar Expert Posts: 68 ✭✭
    Re: Shed

    I haven't built the shed yet but It would be for the solar system only. I would insulate it but I imagine it would get pretty chilly in the winter without some way to warm it. How much capacity is lost due to the cold? Don't have a remote but they make one for the inverter I have. Under what circumstances would I use it?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Shed

    From the Battery FAQ (apparent battery capacity in percent on left scale/temperature on horizontal scale C/(F)):

    Batt_temperature1.gif

    Cycling batteries (charging/discharging) with insulation (foam box for example) can keep them above freezing. I believe one person here has used a battery heater with their genset to initially warm the batteries if they have been cold soaking for a while (batteries do have lots of thermal mass--so they do keep their temperatures fairly well). Note--I am not in a cold climate--purely reading here.

    Inverters, depending on their size, draw 6-30 watts (or even more) just turning them on. If you don't need 120 VAC 24x7, you can save significant energy. Also, in winter, solar systems don't produce much energy in the far north--You do not want to kill your battery bank from an inverter left on and a snow buried array.

    The "nicer" off-grid inverters can include a "search" function... Basically, they use much less power by sending an AC pulse of power about once a second. If there is an AC load over ~6 watts, then the inverter turns on (you turn on a light switch, plug in a laptop, etc.).

    Having a successful off grid solar system usually means being very conservation minded. Almost anything you do to save power--will help a lot.

    For inverter remotes--many do not work over very long distances--So check the specifications/reviews for the unit you are looking at.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • 97TJ
    97TJ Solar Expert Posts: 68 ✭✭
    Re: Shed

    Thanks for the information. The inverter I have has a standby current draw of 0.25 amps. If I do the shed thing, maybe I'll try one of those "pop can solar heaters" on the south side of the shed. I do like the idea of mounting the panels on the side of the shed but couldn't do both the panels and a pop can heater.
  • waynefromnscanada
    waynefromnscanada Solar Expert Posts: 3,009 ✭✭✭✭
    Re: Shed

    Just a heads up, if you are unable to tilt your panels to the vertical for the snow season, it's going to be a real pain in the butt trying to keep them clean. Been there, done that, and now except for the Spring and Fall tilt change, they are out of sight, out of mind and there's no way I'd want to go back tot he way things were.
    Batteries by the way, do create heat within themselves during charging and discharging, so if well insulated, that heat does tend to help keep their temp from going too low.
    Good luck in whatever you do.
  • 97TJ
    97TJ Solar Expert Posts: 68 ✭✭
    Re: Shed
    Just a heads up, if you are unable to tilt your panels to the vertical for the snow season, it's going to be a real pain in the butt trying to keep them clean.
    Thanks for the help. The wheels in my head are turning. I do like the Idea of a "solar shed" but the other thing I have to consider is snow depth. Although this has been a very mild winter, the National Park Service states the average annual snowfall at the cabin is around 300 inches. Maybe I should put the shed on stilts! :D
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Shed

    not the shed, the panels....there are some pictures here on the BB of panels that must be 15 - 20 feet in the air during the summer and snow level in winter.. don't remember where though, maybe BB or Niel??
     
    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
  • 97TJ
    97TJ Solar Expert Posts: 68 ✭✭
    Re: Shed

    I was thinking about how you said you put you panels on the wall of your shed.
  • samuel
    samuel Solar Expert Posts: 80 ✭✭✭✭
    Re: Shed

    My family has a cabin with solar in Northern Michigan (sort of curious how far away you are from me) and I've learned a few things. First off, even in an insulated garage the batteries will average about 30-35°F most of the winter. This isn't too bad but you'll give up about 40-50% of the capacity. This appears to be greater than Bill's chart but that's because of the afternoon overcast skies we seem to get being near L. Superior. Sun until 11am and then clouds. At least at this time of year that is finally starting to turn around.

    Lack of good sun + cold is a big issue. A battery will charge around 90% efficiency from 0-79% SOC or so but after than the efficiency drops off dramatically. At 90% SOC half the energy being put into the battery is wasted. It you have solar that's fine - trickle charge the battery until it's full. In winter with a generator it's not that easy. So now it's cold, batteries lost capacity and you can only really charge to about 85-90% of cold weather SOC before you're wasting gas. Winter can be tough. Just be aware that a generator is a requirement and it's use is highly dependent upon the weather.

    The panels are mounted on a pole and have about a 45° tilt. Very very rarely is there an issue with snow sticking. We also put an 1.5 inch gap between the panels to allow for snow to melt without icing up and cracking the frames (not sure if that is a real concern - but why risk it). We never really considered a roof mount because we couldn't figure out how to mount the panels in a way that allowed the gratuitous amount of snowfall to play nice with panels - ice dams, where would the snow go when it melts, would the snow drift on the roof and cover the panels, etc...

    Take a look at my family's set up and drop a comment or question - I'm more than happy to explain why I did something the way I did and to help out another off-gridder.
  • Jungle Jim
    Jungle Jim Registered Users Posts: 10
    Re: Shed
    BB. wrote: »
    If you have a generator/fuel supply-storage in shed--A fire in the generator shed can take out your battery bank and solar array.

    -Bill

    Hi Bill
    Thank you for the warning about a generator fire taking out the whole system. I am in the middle of planning our off-grid farm's power supply system and should have realized that I was putting all of my eggs in one basket. Now i think we will build a seporate shed for the 20kW Detroit 3-53 and its fuel tank.
    Dennis
  • 97TJ
    97TJ Solar Expert Posts: 68 ✭✭
    Re: Shed
    samuel wrote: »
    My family has a cabin with solar in Northern Michigan (sort of curious how far away you are from me).

    You have a very nice cabin. Mine is still unfinished but it is getting there. We are currently wired for a generator but are hoping to get the solar done this summer. We are in the Grand Marais area about a mile or so from Lake Superior so I would imagine conditions would be similar. I appreciate the information you have provided.
  • samuel
    samuel Solar Expert Posts: 80 ✭✭✭✭
    Re: Shed
    We are in the Grand Marais area about a mile or so from Lake Superior so I would imagine conditions would be similar.

    That's a beautiful area. Despite logic I've been up and down Log Slide more than once ;) My families cabin is about an hour south of Marquette. Good luck on designing your system!
  • erne
    erne Solar Expert Posts: 41
    Re: Shed

    One thing you might consider is installing a solar hot water panel (2X8 ft.) on the South side of your shed about midway up the wall. Inside place a 55 gal. drum of antifreeze as to allow natural convection from panel. Elevate your batteries to allow the same convection to take place. Place a single PEX pipe around the outside parameter of the batteries. On some here at timberline in the mountains of CO. we have had to run a water line at the bottom of the water solar panel to keep the snow depth from burring the panel. The winter temps range as low as -40 degrees or so. Partial cloud cover and wind snow drift is usually a daily occurrence effecting solar isolation. Most of these systems are for repeaters etc. They must work 24/7. A greenhouse wax vent system controls any chance of excess heat on the batteries. Battery temps usually range 50 degrees or higher. The object is to have full avibality of storage capacity. We tilt these water panels 15 degrees as our summer temps are often below freezing at night. All solar electric panels are installed on poles and above snow and rubbing animal levels. The expense of the heating system costs less than one battery. Remember if at your location you are getting to much heat you can partially block the panel.
  • 97TJ
    97TJ Solar Expert Posts: 68 ✭✭
    Re: Shed

    samuel:
    samuel wrote: »
    Despite logic I've been up and down Log Slide more than once ;)
    You're a braver man than me!

    erne: Thanks for the Idea. I think some form of solar heat in the shed is the ticket!
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Shed
    Jungle Jim wrote: »
    Hi Bill
    Thank you for the warning about a generator fire taking out the whole system. I am in the middle of planning our off-grid farm's power supply system and should have realized that I was putting all of my eggs in one basket. Now i think we will build a seporate shed for the 20kW Detroit 3-53 and its fuel tank.
    Dennis


    My battery inverter shed is seperate from the generator shed for the same reason. Hopefully, there will never be a fire, and if so, we could get it out in time.
    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 ,

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Shed

    JJ and others,

    Planing generator sets for safety demands that you really understand your points of failure well...

    One of the common issues is a fuel leak... Some fires have been fed by gravity or even electric fuel pumps feeding fuel into a leaking/broken fuel line.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Shed
    westbranch wrote: »
    not the shed, the panels....there are some pictures here on the BB of panels that must be 15 - 20 feet in the air during the summer and snow level in winter.. don't remember where though, maybe BB or Niel??

    no it wasn't myself or bb, but i believe you are referring to dave sparks if i remember right and occasionally i do.:-)
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: Shed

    Niel, nope, it wasn't you or BB or Dave that posted it, but I thought you might remember... he has a super steep roof and had to snowmobile in , etc. Was probably in Colorado or one of the other high mountain states. Maybe 2 years ago???
     
    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
  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Shed

    i can picture what pics you are referring to in my head, but if it wasn't dave sparks then i'm drawing a blank. sorry.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Shed

    These?:
    Panamapat wrote: »
    We were up this past weekend and got a chance to check on the snow, hoping more had melted, but there was still quite a bit although the panels were clear.

    110326-1054-17.jpg

    Batteries where in great shape from spending 4 months in deep freeze where temps dipped to 25 below zero F outside and minus 15 inside. I used the Rogue to equalize for 30 minutes to get rid of any stratified acid.
    If you think that is bad check out my place!! These winter pictures were taken 3/27/11 Have included one of the summer to have perspective. The one with my truck the snow pole is a 10foot pole! We got over 700 inches this year 4th biggest in recorded history since 1878.
    attachment.php?attachmentid=1690&d=1328644664&thumb=1attachment.php?attachmentid=1691&d=1328644664&thumb=1attachment.php?attachmentid=1692&d=1328644668&thumb=1

    -Bill 8)
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • SolaRevolution
    SolaRevolution Solar Expert Posts: 410 ✭✭
    Re: Shed

    Here is a "Tuff Shed" from Home Depot.

    I helped a DIY do this upgrade from a 25 year old system. The 3 panels on the roof are new and run into the MPPT. The 12 on the ground are old and run into a PWM Tristar at 24 volts. The ones on the roof would shed snow quite well, though this site will probably never get more than 12"

    The house is in the woods +/- 460' down a north slope from this power room. The inverter monitor still works at this distance too. (Magnum ME-ARC/BMK) The array on the roof can be tilted from 30-60 deg +/- .


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  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: Shed

    that's it bill. thanks for finding it.

    solarevolution,
    would those older pvs happen to be solarex?
  • SolaRevolution
    SolaRevolution Solar Expert Posts: 410 ✭✭
    Re: Shed
    niel wrote: »
    solarevolution,
    would those older pvs happen to be solarex?

    Yep. Good eye! Still producing. They could be 30 years old.

    The other old ones are SP75 "hurricanes"
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: Shed
    BB. wrote: »
    JJ and others,

    Planing generator sets for safety demands that you really understand your points of failure well...

    One of the common issues is a fuel leak... Some fires have been fed by gravity or even electric fuel pumps feeding fuel into a leaking/broken fuel line.

    -Bill

    I burned a nice car up that way with an electric fuel pump. It was spectacular to watch the thing burn to the ground.
  • solarvic
    solarvic Solar Expert Posts: 1,071 ✭✭✭✭
    Re: Shed

    Solar Dave, I burnt a 56 buick with an electric fuel pump. The cam that was suposed to operate the fuelpump had the lobe wore off. Luckily the fire dept disconnected my battery cable and I could still run it after I replaced a couple wires.I connected it to the ignition switch so pump wouldn,t run. My wife got out of the car without turning off the ignition switch. :Dsolarvic:D
  • solar_dave
    solar_dave Solar Expert Posts: 2,397 ✭✭✭✭
    Re: Shed
    solarvic wrote: »
    Solar Dave, I burnt a 56 buick with an electric fuel pump. The cam that was suposed to operate the fuelpump had the lobe wore off. Luckily the fire dept disconnected my battery cable and I could still run it after I replaced a couple wires.I connected it to the ignition switch so pump wouldn,t run. My wife got out of the car without turning off the ignition switch. :Dsolarvic:D

    Mine was running when it caught fire, I had run inside and left it running, when I came back the engine compartment was fully involved,and the smoke was pour out the open drivers side window. By the time the fire dept. got there the front tires had burned off and they just took a pumper line to it. Totaled. I was surprised at how long the pump ran.