We now have an installed, approved, and running off-grid solar power utility!
Getting the Permits
The solar and electrical work is one thousand percent Chip's domain. I helped with the paperwork and lifting a few solar panels, but that's about it.
Back in Wisconsin during remodeling on various homes, Chip only needed to submit an appropriate electrical plan, and undergo inspections to ensure that everything was done safely. Here in New Mexico, we learned that to get an electrical permit, Chip needed to pass a state homeowner's electrical test for doing the basic wiring. We also needed a separate homeowner's solar permit with a separate solar test required for utility installation.
In April 2022 Chip passed the electrical test, and then our inevitable delays and reprioritizations set in: plumbing, plastering, interior framing, floor base... once we had the porch built to hold the solar panels, we finally turned back to the electrical job in late 2023...
...Except that now our electrical permit had expired. We were shocked and dismayed to learn that in the meantime state regs had changed. Chip not only had to take the homeowner electrical test over again, but now they said that homeowners are no longer permitted to install their own solar systems!
We knew from pre-COVID estimates that it would cost tens of thousands of dollars to hire a contractor to come out to our remote location and do the work. After a flurry of frantic visits, phone calls, and emails, we got grandfathered in with an exception, and we pulled our permits in February 2024. Phew! We do hope that New Mexico re-thinks this policy: we love chalking up "firsts" with our projects, but would absolutely not take any joy in building the LAST homeowner-installed solar in the state!! In any case, we were grateful to be able to move forward.
Installing the Solar Panels
Chip finished getting sheathing on, and installed the IronRidge rails onto the S-5! feet compatible with our trapezoidal metal roof.
With the help of our scaffolding (a gift from our contractor Marty after his framing job years ago), we hoisted each panel up onto the roof. Our design includes five strings of three panels each. Once we had three panels on the roof, Chip lifted them up onto makeshift frames so he could climb behind them to wire the string up. Then he lowered them back down onto the rails, and we locked them in place, ready to move on to the next string of three.
Chip used the bright tie wraps to color-code the wiring both at the panels and in the Midnight Solar combiner box which holds the circuit breakers. He connected the Tigo rapid shutdown (a required safety feature) before bringing the lines into the house.
Building the Brains
Indoors, the solar control system lives in our utility room at the back of the house. It consists of an AltE pre-wired MagnaSine inverter/charger, charge controller, breakers, and surge protection. Chip wired that up to our batteries, conventional house breaker box, and backup generator switch box.
We had four KiloVault batteries from our original order, and before installing the system there was a huge sale on the same batteries which let us buy four more for an eighth of the price. That took an edge off of the shock that our solar source, AltE, sadly went out of business shortly thereafter, and before we installed our system.
Wiring the House
Needless to say, Chip did all the wiring. Much of this was conventional wiring work, but it was Chip's first time wiring an entire house from scratch. We now have over 1,500 feet of wire in this house!
There were also a few key items that added complexity given our unconventional home. For one thing, of course the shotcrete tire bale walls do not allow for wiring to run behind the wall sheathing. Chip had to choose between metal-clad (MC) wire and running conduit on the outside of the concrete. Our house is mostly open, with few dividing walls. To avoid a billion conduits running all over the concrete, Chip decided to include two sub-panels in the design.
The sub-panel under the east loft serves the east loft, bedroom, bathroom, closet, and utility. The sub-panel upstairs on the west loft serves the west loft, the kitchen below, the outdoor lights and outlets, and the rapid shutdown system. In this way all of those circuits served by each sub-panel only needed the one set of wires from the main panel to that sub-panel. Of course outlets along the concrete walls did also need their own lines from the main panel.
Another puzzle was system grounding, since there is so much contradictory information out there. Chip did a lot of digging on this one, and found a solution which was confirmed and approved by our inspector. The solar utility wiring and house wiring are completely independent, only connecting where the inverter feeds into the main panel, as any utility would. They are each independently grounded to our main house ground which connects to the rebar grid embedded in our foundation.
The off-grid solar also has some incompatibilities with some of the new breakers that require arc fault as well as ground fault protection. We (yeah, that means Chip) have gone through so many AF/GF breakers. Our electrician friends tell us these cause all sorts of problems even in conventional homes, but that using them in an off-grid settings adds another layer of variables. Chip has had success in switching out to unprotected breakers in the panel, and instead protecting the circuit with AF/GF plugs as the initial plug on each circuit.
Overall, we were grateful we didn't have an electrical contractor and a solar contractor pointing fingers at each other when problems came up! I just pointed at Chip, Chip pointed at himself, he fixed it, and everyone was happy...
including the inspectors!
Testing!
When our electrical inspector came out to sign off on the rough inspections for both the solar and the wiring, he told us to go ahead and start testing and using the electricity.
This is one aspect that I get to help with, and we are working on it every day!
We had our final solar inspection on December 26, and that system is fully approved. Our first signed, sealed, and delivered permit for our actual house! Once the walls are covered up, we will have our final electrical inspection. Progress!
...and did I mention we got our 2024 solar tax rebates...?!
I got an email from a friend who tried to post her question here, asking for a septic system update... but it's all on hold, since we don't have water yet! We are very close to getting our plumbing "top-out" permit, after which we will be able to start hooking up fixtures. After that is done, and we get our final plumbing inspection, we will be able to start using the plumbing. Then three months after that we will take our first effluent sample to the testing lab, and will post a real update! We do have worms living in the bin now, and we have been feeding and watering them through the sewer cleanouts. We opened it up o…
You two are amazing and form one heck of a team. Think about your feats all the time and continue to be impressed. The rewards for all your efforts, I am sure, are coming daily and you get to enjoy the fruits of your labor.
Andy
How exciting! Looks great.