The graph is from the electric company website showing my usage for a single day last week. It was sunny all last week, so pretty much every day’s usage looks like that graph. The little peaks around 1pm are when I made lunch since I can’t run the electric range from the power station. I could have run things for about 3-4 more hours from the power station, but I like to end the day with it charged to at least 90% in case I need to use it for a power outage.
This is just my trial PV setup with 800W of PV on the south-facing side of the house and another 800W on the west-facing side so I get a pretty continuous 600W throughout the day. I’m currently using an Anker Power Station which is limited to 60V and 600 watts of input, so I’m not getting the most out of my PV panels.
Today I ordered two, big 16 KWh batteries and a 10KW inverter to finally start my “big boy” PV installation (for comparison, that’s 32x the capacity of this power station and 5x the total wattage in addition to supporting 220v split-phase). That will let me take better advantage of the panels since I can put all 8 in series for less losses (partial shading notwithstanding).
I’ve been planning on building this out all winter and am finally seeing it through. Totally unrelated (/s), but my electric rate just got hiked another $0.01/KWh so I wanted to get this in place before A/C season kicks in.
How do you do the utility transfers? Also of this is only partial, small load for your household, how is that able to be broken out for the graph?
The main things I run from it are all downstairs in the basement and within reach of extension cords: homelab, WFH office, washing machine, etc. Those are lazily run through the drop ceiling to not be trip hazards. I did install a second outlet behind the fridge upstairs and ran romex down to the basement for it. That was from an earlier plan to have a subset of outlets that were on a backup circuit, but I changed my mind and opted for a whole house solution. So I just put a plug on the end of that (basically turning it into a sort of heavy duty extension cord) and hook it into the power station during the day.
To transfer them back and forth, I just switch where they’re plugged in. They’re all on UPSs (including the fridge - long story) so there’s no power interruption. For other stuff (like charging the lawnmower and power tool batteries, etc) I’ll just either run an extension cord out of the basement or plug the tool chargers into it (it’s got 4 outlets and can put out 2,000 W).
The graph depicts the utility usage, and the bit in the middle where it’s low/negligible throughout the day is just those “base” loads missing / not using power.