diy solar

diy solar

~100kwh for 24/7 off grid home

You can bury the entire line with transformer at the end, how long of a driveway are we talking?
yes you can, but they wanted even more $$$. ~1000’ down the new driveway from their last pole. they mentioned something about maybe having to upgrade that branch, too, since this was at the end of it. not that it matters now, we’re fully committed to 100% battery and solar.
 
You can bury the entire line with transformer at the end, how long of a driveway are we talking?
Yes he could. If it costs $30 - $40 k for pole mounted service I can only imagine how much more just the wire cost would be for underground service. They get by with very skinny wires overhead because they are air cooled. Wires in conduit have to be larger. That is just one of many reasons underground is a lot more expensive.
 
No. It'll live in the great outdoors, on a concrete pad. The boxes have 2" of insulation, a radiant barrier and will be fitted with some heating elements between the packs before winter.

Okay.
Even in Maine weather you feel no enclosure is necessary? How low do temps get there and how high will the snow get?
 
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After 450 miles of driving last night, all of the batteries and the inverter are now up in Maine at the top of my driveway. I need to do some site prep before I can place them.

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The telehandler really shines when you need to reach in to pick something up. This one came with frame levelling (not something I sought out when I bought this machine used, but a killer feature I am happy to have.) So even though I parked the trailer on a spot that wasn't completely level, I was able to get under the boxes to pluck them off.

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Yay!?
 
They estimated somewhere in the $30-40k range. We have a really long driveway, and would need transformers and poles and we'd have to draw up a utility easement, etc. etc. etc.

All in, with inverters and all the fixin's, I should come in at well under $20k. The panels will be more, but will still leave us well under their estimate.

Wow, I'm waiting to hear back from the utility company with their estimate to bring power to my yet to be built house. It's around 500 feet away, easement in place but not sure about transformer upgrade yet. Anything over $10,000 just doesn't make sense to pay an utility company anymore, also I have to have solar installed by code and the utility company cuts power for "safety" several times a year.
 
I mean an out-building enclosure for those blue enclosures. Nevermind though. He's set on leaving them exposed.

No, that's not quite right. I'm trying to follow a data-driven approach, here. I can insulate the boxes, because it's cheap and there's space within them to do that. The heating elements are likewise inexpensive and easy to implement.

I'll monitor the inside / outside temperatures closely, and if I'm seeing that the heaters/insulation simply cannot keep up with the weather, then I can still build a building around them, as long as I'm careful not to preclude that option. Until then, it's KISS.
 
Will be interesting to see the effects of prolonged exposure to elements...snow/ice/rain/humidity/cold/heat//UV/wind/etc. Please keep us updated on that aspect.

Very cool project.
 
Speaking of data... I had one of the boxes rigged up with a data logger to watch the temperature at the center of the pack and the outside temperature (taped to the underside of the box, so it was shaded / shielded from the wind.)

I've attached a graph of about 18 days worth of data. The black line is the ambient, and the green line is inside the box. Note, that the lids of the boxes are not yet insulated and there is no active heating or cooling. The boxes seem to heat up about the way you'd expect, sitting in the sunshine.
 

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Is that operating or not operating? I suspect the troughs before sunrise will be less deep when everything is hooked up and running. Even before the lid and heaters.
 
Cool, looks like you are doing what I am doing...I found a solar site nearby that was public in Tennessee from an inverter website. Found one in Maine, that helps figure out what solar you would need, and how much you would run the generator. https://www.sunnyportal.com/Templates/PublicPage.aspx?page=be0fa316-9656-4586-8969-c360e304ec58

My design is almost the same, in TN. Will be about 100kwh battery, atm just a temp system with 18kwh and 10kw solar (will expand to maybe 20kw) to use during construction. East/West solar arrays are probably better offgrid to get longer sunlight if possible. For me I built a pole building and a room inside for battery etc. Put the solar panels on top. I am building almost to passive house standards. If you want construction resources, or channels to follow let me know. Definitely noticed you are using zip tape on the boxes ;-)
 
Here is an overview of some stuff. If you have something specific you are wanting to know or figure out let me know. If you are 100% offgrid, Heat pump water heaters, Heat pump dryers (miele makes some), mitsubishi minisplits can be great (do single units, not multihead units) , basically look for the most energy efficient solutions. In the USA windows are pretty terrible, so look to upgrade those to european style / high energy efficiency windows (You'll pay a lot for them) Typical wall can be R-20, but the windows are usually like R-3.

Another interesting tidbit, without insulation over the studs to prevent thermal bridging you will only get like r20-30 no matter what you do in the wall. So try to insulation on the outside of your house somehow outside of the studs/structure.

Joe Lstiburek's Builders guide to....for your climate.
https://www.amazon.com/Joseph-W.-Lstiburek/e/B001JS3N9C?ref=dbs_a_mng_rwt_scns_share

https://www.buildshownetwork.com (builder's netflix....Great energy efficiency stuff)

GreenBuildingAdvisor.com

https://kimchiandkraut.net/tag/passive-house-blog/ (how to build to passive house

Remote building for cold climates (Alaska manual/how to)
http://cchrc.org/remote-walls/
http://cchrc.org/media/REMOTE_Manual.pdf

Unity homes for well built energy efficient houses or shells shipped.
https://unityhomes.com/

How buildings work/construction science.
https://unbuilditpodcast.com/
 
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Is that operating or not operating? I suspect the troughs before sunrise will be less deep when everything is hooked up and running. Even before the lid and heaters.
Those are not operating. Just sitting in the elements, not far from where they'll be installed.
 
Here is an overview of some stuff. If you have something specific you are wanting to know or figure out let me know. If you are 100% offgrid, Heat pump water heaters, Heat pump dryers (miele makes some), mitsubishi minisplits can be great (do single units, not multihead units) , basically look for the most energy efficient solutions. In the USA windows are pretty terrible, so look to upgrade those to european style / high energy efficiency windows (You'll pay a lot for them) Typical wall can be R-20, but the windows are usually like R-3.

Another interesting tidbit, without insulation over the studs to prevent thermal bridging you will only get like r20-30 no matter what you do in the wall. So try to insulation on the outside of your house somehow outside of the studs/structure.

Joe Lstiburek's Builders guide to....for your climate.
https://www.amazon.com/Joseph-W.-Lstiburek/e/B001JS3N9C?ref=dbs_a_mng_rwt_scns_share

https://www.buildshownetwork.com (builder's netflix....Great energy efficiency stuff)

GreenBuildingAdvisor.com

https://kimchiandkraut.net/tag/passive-house-blog/ (how to build to passive house

Remote building for cold climates (Alaska manual/how to)
http://cchrc.org/remote-walls/
http://cchrc.org/media/REMOTE_Manual.pdf

Unity homes for well built energy efficient houses or shells shipped.
https://unityhomes.com/

How buildings work/construction science.
https://unbuilditpodcast.com/
We're building a SIP house, 10" walls, 12" roof.
 
Is that operating or not operating? I suspect the troughs before sunrise will be less deep when everything is hooked up and running. Even before the lid and heaters.
Also, it looks like there were only three days that the pack got below 5°C, which is going to be my trigger for the heater. Many more days where the ambient fell below that. It'll be interesting to see what the effect will be this next winter.
 
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