New Construction, looking for advice regarding off-grid system sizing

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  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing
    Rossman wrote: »
    so was looking at something like this, but I don't know if that "power saver" tech is worth anything at all in regards to off grid...

    I have Lennox, but older model, about 4 years ago, 96% efficient. It is very quiet and works well. Mine wasn't designed for off-grid. The energy consumption depends on duty cycle which changes a lot depending on many factors. The problem with Lennox is that they don't sell their products and you will have to hire a contractor. I live in rural area, and the only contractor I could get was really bad one.

    Forced air is not the only choice. As an alternative you can embed pipes into the floors and heat it with hot water that is heated by tankless water heater. It is supposed to be more efficient system which produces radiant heat. Supposedly makes you feel cozy and let you keep thermostat at lower temperature and still feel warm. This might be more efficient. But I don't know much about it.
  • Rossman
    Rossman Solar Expert Posts: 178 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    Ya, we thought about using in-floor radiant heat, but it seems harder to get real info on. If I just get a gas furnace they seem more well understood.

    We got a pretty high end lennox furnace and AC put in our city house a couple years back and the contractor was great!! They did an excellent job and we have been very happy with it. But I am not set on that brand at all. I guess I can pretty well just pick any furnace and go for it, I'm not hearing anyone telling me to be careful for anything in particular on this front!

    Thanks,
    mark
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    Since you are of grid and 'out there' do you plan on using any other forms of heat, ie wood cook stove or wood heater in the basement? or an external multi fuel furnace?

    In floor heating installation of piping is a snap once you get a hand on how 1000 feet of pipe will unwind on you, when you are not expecting it. Her is a new product that combines insulation and clamps for the 1/2 in Pex pipe.
    http://www.beaverplastics.com/Insulation/documents/insulworks.pdf a Canadian made product.
    TIP: make sure the fill under your floor is REALLY level. I thought is was OK to good but when the styro went in the high spots became evident quickly.
    I did it for future installation of radiant heating, problem is you can't do it after the concrete is laid... so if you think you might do it now. BTW the basement is warmer than the upstairs in winter with no heat.
    Also if you will have a full height basement in ground , recommend using ICF's insulated concrete forms http://www.logixicf.com/. They cost a bit more but only takes 3 guys 2 days to put it all in place for a 32' x 38' basement. But hire a carpenter who has done/used it before. Probably saves a fair bit of money if you are isolated. Matter of fact you can build the entire house out of them.

    here is our place as of last month.
    Attachment not found.Attachment not found.
     
    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
  • Rossman
    Rossman Solar Expert Posts: 178 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    Surprisingly, we are not that isolated! Just 6mins outside town at the posted speed limit! Just no hydro to our lot.

    Ontario Hydro wanted $7k from us just to "design" the proposed solution to bring the grid out - I'd then have to fund the construction of whatever that design specifies.

    For that price I feel ok about going with an off-grid solar setup with external propane tanks for gas. The power lines are not even well maintained out there and outages are common.

    We looked at ICF but will instead use ROXUL drainboard on the exterior of the poured concrete foundation...the regular foundation guys are more readily available from what I have found. Same with in-floor radiant heating - any time we have talked to anyone about these they start quoting astronomical figures...it's pretty intimidating.

    Real nice place, westbranch!

    Thanks again for the responses! Love how helpful this forum is!
  • westbranch
    westbranch Solar Expert Posts: 5,183 ✭✭✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    I hired a cement floor finisher, cost about $1 per sq ft. I thought that was reasonable as they had a 4 hr drive one way, an overnight stay, and they didn't leave till after 10 pm and drove home. looks like a mirror.
    Attachment not found.
     
    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
  • vtmaps
    vtmaps Solar Expert Posts: 3,741 ✭✭✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing
    An oven can be a nice source of heat up there and so I would use the Peerless. You can bake all day and use zero energy.

    Are you suggesting to heat the house with an unvented propane oven? --vtMaps
    4 X 235watt Samsung, Midnite ePanel, Outback VFX3524 FM60 & mate, 4 Interstate L16, trimetric, Honda eu2000i
  • Rossman
    Rossman Solar Expert Posts: 178 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    Real nice westbranch. Yeah we'd considered polished concrete but decided against because it's a bit hard on the knees from what we've heard. Lots of reports of people who've had it, saying they would never get it again, etc.

    Thanks again!
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: New Construction, looking for advice regarding off-grid system sizing

    My only experience with polished concrete was that it can be very slippery when wet. For a friend's outdoor walkway--Had to use a bit of acid to etch the surface to make it safer.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • northerner
    northerner Solar Expert Posts: 492 ✭✭✭✭✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    I know someone that has an in floor heating system and uses a tankless gas heater that works for both the heat and hot water. Apparently, there can technical problems with the tankless heaters, and also can be difficult to find a technician that knows how to service and repair them efficiently. They just had a problem with theirs, and it took numerous trips from a local plumbing outfit, to finally resolve the problem. If I had a choice, I would stick with a regular forced air furnace.

    If you live in a cold climate, an HRV makes sense for fresh air, as you recapture some of the lost heat. It is not difficult to incorporate the HRV into the furnace ducting, and as mentioned have it come on only when the furnace fan is turned on.
  • Rossman
    Rossman Solar Expert Posts: 178 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    Sounds like a plan, westerner.

    We are finishing off the actual house plans this week and once we have that, can engage an HVAC person to talk about selecting a furnace. We are going to have a 24k BTU gas fireplace in the living room, no power consumption there at all, so maybe that can get us thru spring and fall, any time except for the dead of winter. Not sure, exactly. We are going to have double-stud 12" exterior walls, so we will be well insulated.

    I don't really know a lot about HRV's, are the intended to also duct away moist air from bathrooms, and for example the vent hood in the kitchen above the stove? Is the purpose of them to reduce vents out the side of the house at those locations?

    EDIT: Found this good overview!

    Cheers,
    mark
  • Rossman
    Rossman Solar Expert Posts: 178 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing
    NorthGuy wrote: »
    very small electric water heater to smooth undesirable effects of tankless heater

    Hey NorthGuy, I meant to ask you about this comment...what are the undesirable effects that you are trying to eliminate? I'm still on a regular water heater here in the city, never really used a tankless/on-demand system.

    Thanks,
    mark
  • NorthGuy
    NorthGuy Solar Expert Posts: 1,913 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing
    Rossman wrote: »
    Hey NorthGuy, I meant to ask you about this comment...what are the undesirable effects that you are trying to eliminate? I'm still on a regular water heater here in the city, never really used a tankless/on-demand system.

    When the flow of the water increases (the most notable case when the heater is turned on), it takes some time for the heater to increase the heat to match the flow. This is a very short time, but cold[er] water manages to get into the pipe. This is not such a big deal, but may be unpleasant whet it catches you in the shower. My wife doesn't like that.
  • Rossman
    Rossman Solar Expert Posts: 178 ✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing

    Ah, interesting. Thx!
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: New Construction, looking for advice regarding off-grid system sizing
    NorthGuy wrote: »
    When the flow of the water increases (the most notable case when the heater is turned on), it takes some time for the heater to increase the heat to match the flow. This is a very short time, but cold[er] water manages to get into the pipe. This is not such a big deal, but may be unpleasant whet it catches you in the shower. My wife doesn't like that.

    I got a Eterna brand heater, it has a 2 gallon tank inside and a 3 stage burner, to help control fluctuations.
    eternalwaterheater.com
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