diy solar

diy solar

Barn (Off Grid) Where to Start (to grow)

PV/battery backup is nicer whether you have a generator or not, gives you smaller amounts of power 24/7 with generator running occasionally or not at all.

Trencher, bury 2" or 3" PVC conduit 18" under ground. Thread a pulling line through it as you assemble conduit. With 6 awg or 2 awg pulled through it you can deliver 70A or 125A 120/240 or 208Y. 2/0 AWG works, but requires much more to pull, like a winch or tugger. Or pickup truck? (avoid bends.) Oversize conduit makes it easier. Put in additional conduit for phone/data/control and poly pipe for water while you have a trench.

Whether you feed utility power or use PV/generator, having the buildings tied together will be useful.
You can install grid-tie PV on both (the most economical form of PV), and later they can be part of an off-grid system if you select what family of products you want to use.

You can DIY a grid-tie PV system for $1/watt which will give you power for $0.05/kWh amortized over 10 years. Maybe replace inverters if they fail, and by 20 years the average amortized cost is down to $0.03/kWh

Anything battery costs considerably more, in particular the wear out and replacement cost of batteries (or high upfront cost of batteries that can deep cycle every night for 10 to 20 years.) Prices are coming down. So to start, if you want battery backup for grid failure, you can undersize battery and shut of excess loads. My daily PV production peaks at 5x my battery capacity, could probably make it work at 10x or more; that's excess AC production for daytime use, minimal loads at night. e.g. run A/C and pump water while the sun shines.
 
The reasons I mention this, is because I designed & build my home to be Net Positive.
FPSF Slab Foundation using 4" of HD-XPS under & up the sides of the slab foundation, with 3/4" Pex for Radiant Heat in it.
Walls are 2x6 "Advanced Framed 24 OC" with 5-1/2" of High Density closed cell EPS-II no space between sheathing & interior wall material.
(Cement truck rolled over a piece of it and only left 1/4" deep tread marks in this foam.... (High Density R6 per inch)
Roof (Cathedral ceilings) is 2x8 with 7-1/2" of PolyISO between the rafters, two layers, 1 with 4" thick ISO, 1 with 3.5" thick ISO.

Cool Roof System installed, with 2x4's battens laying on their flats above the rafters with 1x6 cross battens for the metal roof, this provides for the convective airflow from the eaves up through to the Ridge Vent.

Siding in my case is Live Edge White Cedar, installed in a Rainscreen fashion. I also have battens running up along the studs with cross batten that have the 8" Cedar Back Planks nailed to with 4" separation between planks and then the Live Edge Face Planks covering that gap. This allows air to move freely with no cold / hot spots or anywhere for moisture to collect.

All exterior walls are "solid" meaning there is no electrical or plumbing running within... Electrical is all surface mounted on exterior walls where needed. Interior walls have wiring within of course. All plumbing is also "surface mounted" and installed without messing up the envelope.

Doors & Windows are installed within Bailey Boxes passing through the walls and as such extend my widow sill to 6" as it places the windows where they belong. The catch is my walls from Inside drywall face to outside cedar face is 9-1/2" thick, so Bailey Boxes were needed anyways.

WHERE DID I GET INSULATION LIKE THAT ?
It is NOT sold in Retail Land, you wil never see 3.5" or 4.0" thick 4'x8' sheets of ISO in a retail store, nor will you ever see 5-1/2" HD-EPSII Insulation either in retail. I sourced it all from Commercial Roofers (think Office towers, shopping malls.) and WAY CHeaper than Retail Hell !
You are in Ontario so much of your suggestions don’t help me much but I always love hearing what works in other places. Post a link to the foam you’re talking about. If it’s what I think it is you get a ~R-4/inch which is fine if you have plenty of room. I do have 8” exterior walls but I can get nearly double the R value with closed cell SPF. I’ve got a commercial project with hollow core roof what we are spraying because the foam thickness didn’t work. Also, I personally don’t care for it as you get it in sheets and while it’s better that pretty much anything other than closed cell spray if you get a hole in your flat roof it’s easier for water to find a way through the panels. Walls it’s fine. Curious why no electrical on the exterior walls for you? Is is that cold that it makes a difference? I get plumbing.
 
Back
Top