Future solar – today’s panel – anything I need to plan for
orange_cat
| Posted in General Questions on
I am finalizing electrical panel in a new build.
If I were to add a solar (not in the cards now) let say in a year, a small amount (I have a south facing unobstructed sloped roof portion for about 7.5-10kw of panels and we are considering adding mounts to the roof details, so can use that may be to shave off some of the electrical load) – do I need to do anything differently to the electrical panel? Electrician in the house this week, no time to loose.
I also have not been able to locate a reputable solar company in Toronto, so if someone has recommendations – I am keen to hear them.
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Replies
You want either a PV ready panel that has dedicated feed for the PV inverters or in case of a 200A service, you want a panel with busbars rated above 200A otherwise you are limited to 7.6kW of PV on a "standard" 200A panel.
Running a 1 1/4" (1" can work if space is tight but harder to fish) conduit from your panel up to the roof is also much easier when the walls are open. The wires can be fished later when the PV is installed.
Thank you very much!
I recommend using EMT for that conduit run. EMT is steel conduit, and provides a little bit of protection if you have any issues with lightning. Be sure to ground the bottom end of the conduit.
Another option is to set things up with your meter feeding a tap box, then feeding your main panel from that tap box. The solar panels can then be connected through a seperate breaker and "panel" also off that tap box. This is sometimes better than a PV ready panel, especially if you want to go with "400A" electric service, although in that case I'd use a larger "main" panel with 400A bus, and feed 200A subpanels off of that main panel. This is all more complex than a PV ready panel, but may be another option for you depending on what your plans are (and, these days, depending on what you can actually get at the supply house!)
Bill
Thank you. I currently have a 200amp service (and getting 400amp is not guaranteed and lengthy wait and separate application and fees, fees, fees), so trying to kep it under 200amp through careful usage.
Running Romex through the walls now is cheaper than running conduit for both labor and materials. It also saves the cost of the wire down the road.
The downside is you have to know what size wire you'll need.
Some of the hybrid inverters, like Solark's 15k and EG4's 18k have a 200amp pass through, so they would go in between the meter and a traditional 200amp panel. Just mentioning because if the electrician is there, might be too late to change to a solar ready main panel.
Thank you!
I always told people the safest approach is a conduit from your roof to your crawlspace. And another from your panel to your crawlspace.
3/4" is plenty for the size you mentioned(1 1/4" way overkill and hard to work with)
The reason to go into the crawl is depending where you are you probably will need to land in a exterior disconnect before you land in your panel.
Of course this advise is mainly targeted toward using micro inverters. If you don't have a crawlspace you just need to have it all pretty planned out.
When I built my house for regulatory reasons the solar could not be installed until after the house was occupied. I reached out to a solar installer and signed a contract about 18 months before we finished. They priced the contract based on the house plans and photographing the site with a drone. During construction they ran wiring from the basement to the roof when the rest of the electrical was being roughed out, and when the roof was being installed they put mounts up ahead of the roofers.
Once we had our certificate of occupancy they came back and put the panels on the mounts and hooked up the wires. I think they did it all in one day.
I did have to put down a down payment upon signing the contract. The agreement we had was that if I ended up not getting approved by the utility they would refund everything but the cost of the work they had already done. The upside was that they honored the contract price 18 months later.
A 2" conduit from the main electrical panel to the roof, as other have said should be installed, for future solar PV wires to be run in, or just run 200-amp rated cable to a junction box at each end.
Solar PV is generation not consumption, so solar PV generation only effects the busbar size of the panel, not the electrical panelboard capacity. So you can either put a panel with a larger rating (the bus bar determines the rating of the panel) and install a smaller main breaker in it (this cost about $350 more then a typical 100-amp panel install materials from a recent quote) or leave space to or just install a splitter box which allows the solar PV array and the main electrical panel to both connect back to the electrical meter. Blackbox electrical in Calgary, Alberta, Canada makes a good unit that can be sized to your needs.
ahttps://www.blackboxelectrical.com/products/feed-through-or-splitter-box
You should be able to fully electrify a high performance home in Toronto on a 100-amp 240-volt electrical service. It has been done a number of times in Alberta. Here is an article I wrote with product options and I have a longer report if you want.
https://b2electrification.org/home-electrification-service-upgrade-not-required
Note that 6 months after you move into the house you are eligible for the Greener Home Grant and Loan, so waiting for then to install solar is a good idea.