Advice on solar hybrid setup (EG4 18K + powerpro 14kWh)

Hi there,

Noob here looking for advice. I'm looking to install EG4 18K + PowerPro batteries (will hire an electrician). I am unfortunately in California and NEM3.0 is in effect for me. I do not have any system installed currently.

My house is very old (1960's) and the grid service comes from one corner of the house that is diagonally opposite of the garage. We have an EV and we did have an electrician install a subpanel in the garage mainly for the EVSE and things around the garage.

My requirements are:
- Install the inverter & battery in the garage and use the existing wiring to the sub panel as the grid connection. I'd prefer to keep these equipment in the garage to keep it out of the elements. The main service panel is where the sun shines on for half of the day.
- I'd like to have the flexibility of bringing on more batteries in the future without spending a fortune (the powerpro's appear to be of great value compared to others).
- Power the sub panel in case of an outage, the rest of the house is ¯\_(ツ)_/¯. This I know would be possible via the 18K and/or 6000XP.

One thing I am unsure of is if we can offset our power usage with solar and battery during the day and night (until a certain battery threshold) when there is no outage. In the 18K manual, it has a system diagram with a peak shaving function. I presume this is close to what I am looking for except it is just to export it at a schedule?

Is there a better system architecture that I am not aware of?

Thanks in advance.

davecl9001 said:

One thing I am unsure of is if we can offset our power usage with solar and battery during the day and night (until a certain battery threshold) when there is no outage

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You can, this is a key selling point. You will need a CT sensor though in the appropriate place to detect the amount being pulled from the grid.

(Important trivia) EG4 has NOT covered all possible ESS regulations that PG&E (and perhaps other POCOs) impose. Search for threads on PCS. If you are serious about being a customer please help us out and pressure EG4 for a resolution. I am not a serious customer so I can’t complain at them in good conscience or with expectations that they rationally should even listen to me. Suffice it to say, do not buy anything until your interconnect application and building permit are done. And if it turns out EG4 cannot address this there may be some awkward $$$ situation if your plans designer charges to swap to SolArk.

(useless trivia) The 18kpv also has a forced export function but I don’t think it is optimized to harvest game NEM3. The way to do that is to push out power the 30 hours each year where the pay back function is 10x of normal.

zanydroid said:

You will need a CT sensor though in the appropriate place to detect the amount being pulled from the grid.

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(2 sensors actually one per leg)

And note there are details around fitment of the sensors in your electrical panels. Some require more effort and cost to squeeze them in than others

zanydroid said:

You can, this is a key selling point. You will need a CT sensor though in the appropriate place to detect the amount being pulled from the grid.

(Important trivia) EG4 has NOT covered all possible ESS regulations that PG&E (and perhaps other POCOs) impose. Search for threads on PCS. If you are serious about being a customer please help us out and pressure EG4 for a resolution. I am not a serious customer so I can’t complain at them in good conscience or with expectations that they rationally should even listen to me. Suffice it to say, do not buy anything until your interconnect application and building permit are done. And if it turns out EG4 cannot address this there may be some awkward $$$ situation if your plans designer charges to swap to SolArk.

(useless trivia) The 18kpv also has a forced export function but I don’t think it is optimized to harvest game NEM3. The way to do that is to push out power the 30 hours each year where the pay back function is 10x of normal.

Click to expand...

Thanks for your response. For the CT sensors, I would think this is needed at the main panel, correct? Would it be possible to wire it from the main panel to the garage that is opposite end of the house?

EDIT: found it in the manual:

The CT wires can be extended up to 300 ft. (around 100 m).

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davecl9001 said:

Thanks for your response. For the CT sensors, I would think this is needed at the main panel, correct? Would it be possible to wire it from the main panel to the garage that is opposite end of the house?

Click to expand...

Yes, basically every load below the CT location can be offset and everything above will not.

The distance is probably in the manual. I don’t remember the exact combination supported by this inverter. Typically there is a distance for analog direct wired CT and another distance for CTs that first go into a digital energy meter close to the measurement location and then hop into a serial data cable for the trip to the inverter.

Some brave souls also hack in a wireless hop for this data connection, it is likely not code compliant without permission

If you do have any further questions, feel free to reach out!