According to the web site, it is a replacement for a traditional electrical panel with phone control added.. You need and electrical load analysis to determine what size (100 amp - 400 amp) panel you need given the "new" appliances (maybe you existing panel can handle the new load). There are places on the net that can help you do that analysis.

Can you explain a little more what the upgrade is that you're concerned about? To use this smart panel, it seems like you would have to remove your existing panel and wire this in, and I'm not clear on how that would be less expensive than simply putting in a larger capacity breaker box or a sub-panel. Do you have information that leads you to believe that your project would otherwise require you having to replace your existing service cables with larger gauge cables, and this smart panel will prevent you having to do this (and you think that new cabling would be a huge expense)?

It's not how much you're drawing from the grid but how much you are drawing in total. This assuming that you load balance (grid + solar) before your panel which is typical. (The other option would be to have one panel for grid connected circuits and one for solar connected circuits but I'd recommend against that.)

Also, there are still likely to be cases where you will be 100% grid unless you are OK with not having some electrical things available when solar+battery is not available.

So, I think you will likely still need a panel capable of handling the entire electrical load of your house in order to meet code.

I believe Span uses standard dumb breakers and just has their electronics behind it. A significant problem w/ new electrical panels is AFCI nusiance trips (think having to reset a breaker once per week or day). Some panels such as Square D's new stuff are doing a much better job than others such as Eaton or Siemens so something to think about.

Thanks for the responses. Just to clarify: it’s my understanding that there is a requirement in SF (either building code or PG&E policy) that the main/service panel must be rated to handle the amperage of the entire home load as if it were all turned on at once, even though (a) we will never have everything turned on at once; and (b) most of our power will come from our new solar + battery. I’m hoping to find out if anyone has experience getting around that requirement using a smart sub-panel, which is one of the selling points on Span’s website.

Kelsey-

I know you're looking for relevant personal experiences, but you might also get useful info by talking with tech support folks at Span.

Thanks; I’ve already scheduled that, but they aren’t available for over a week, and I’m trying to get info ASAP in case I need to modify my plan with PG&E and my contractors.

How to get around the SF electrical policy: Disconnect from their grid. You're looking for a work-around for a policy you don't like. It's not going to happen. Live with their rules or disconnect.

Hi Kelsey, can you share what your resolution was for this? We’re half way through electrifying and up against the exact same issue—we have 100A service, and installing a heat pump will run up against that, unless a smart panel can help better manage loads and avoid an upgrade.

We were able to convince our electrical inspector to use 1 year of actual data instead of our load calc, and he signed off on it after seeing we never got above about 50% of our rated service. Also, are you in the Bay Area? If so I can connect you to people who may be able to help with this issue.