You’ve got a lot going on there. Didn’t mention the GENERAC. How does that contribute?
Fundamentally, one IoTaWatt can monitor 14 circuits. A 240 volt (double breaker) circuit that uses a neutral wire (“three-wire load”) requires two or one if there is enough wiring slack to pass one of them through the CT in the reverse direction. There are other ways to combine things, but without getting into specifics, lets talk about the overall strategy.
I’d recommend monitoring monitoring each of the three panels in their entirety with CTs on the mains. That will require six inputs to the IoTaWatt leaving 8 for individual circuits.
The larger loads are:
- Unknown 100A
- Sub-Panel (measured separately)
- Water Heater
- Geothermal Up
- Geothermal Down
- Geothermal Water pumps
- Electric Heat Elements
- Tesla Charger
You don’t need to get this right off the bat.
Initially, you will be able to breakdown the usage by panel and, to some extent the 120V loads in each panel will be divided between the mains so you will be able to narrow any large users down.
I’ll need a picture of the inside of the sub-panel to know what’s required and possible in there, especially since that’s where the likely suspects are.
You will need one or two CTs for the Hot Tub.
Then depending on the sub-panel layout you should be able to monitor most of the circuits in there.
The Tesla is probably straight two-wire 240V so one CT.
UPDATE: Didn’t mention but hot tubs can be a major drain in the winter. If yours has good insulation around and under (talking well molded thick foam) you have a chance. Evaporation is the whole ball-game here. Even the best fitting covers don’t compare with a well fit floating “bubble-wrap” type cover inside to stop evaporation. You don’t need an energy monitor to see if that’s the case.
Keep track of how much water you need to add. Ball park calculating a gallon of water weighs about 8.4 lbs. You lose about 1000 Btu/lb of water that evaporates (latent heat). So every gallon lost is about 8,400 Btu. 3412 Btu/ kWh means each gallon evaporated loses about 2.5 kWh of heat which must be replaced (plus the Btus required to heat the replacement water to standby temp.).
I’ve also seen where the pumps can use as much as 500W and sometimes run for 12 hours or more just to filter. That’s 6 kWh.