Peter from Manasquan, NJ has been a Green Sun Energy Services client since August of 2020. The generator went in that winter; the car charger followed nearly five years later.
A 16 kW Generac on a managed whole-house switch
Commissioned on 6 January 2021. The calculation asked for a minimum of 15 kW under NEC Article 220 Part IV and a 16 kW Generac Guardian went in on natural gas, behind a 200-amp managed whole-house transfer switch with two smart management modules. The house is 3,000 square feet with two refrigerators, a dishwasher, a washer, a gas dryer and a well pump – and the well pump is the entry that changes the argument. A house on a public main loses its lights during an outage. A house on a well loses its water: no taps, no shower, nothing to flush with, from the moment the power stops. A pump is also a motor load that draws a surge every time it starts, so it shapes the sizing as well as the reasoning. The machine has been on our Diamond plan since: annual maintenance, extended parts-and-labor cover and remote monitoring that Green Sun runs directly.
A GM PowerUp charger on a 60-amp circuit
12 November 2025. The household supplied the charger – a GM PowerUp Level 2 unit – and we hardwired it in the garage on a dedicated 60-amp circuit at 11.5 kW, roughly 36 miles of range an hour. Supplying your own hardware is perfectly reasonable, and it makes the wiring the whole job: the circuit, the breaker, and the question of whether the service can carry another large load.
Five years apart, and the number that decided it
With the charger included, the calculated minimum service for this house came to 169.43 amps against a 200-amp panel. Comfortable, but not the kind of comfortable anybody should assume – thirty amps is less headroom than it sounds when a well pump and a car charger can both decide to start at once. The generator is the reason that question was easy to answer in 2025: the service had already been surveyed properly in 2020, every load counted and written down, and the two management modules were already in place to arbitrate between them. A charger added to a house with a standby generator is not simply another circuit. It is a large intermittent load that the machine may one day have to carry alongside the pump that keeps the water running, and it is worth knowing which of the two gives way first.
Project Facts
- Location
- Manasquan, NJ
- Services
- EV Charger Installation, Standby Generator Installation, Standby Generator Service
- Client since
- August 2020
Standby generator
- Manufacturer
- Generac Model # 7178
- Rated output
- 16 kW LP / 16 kW NG
- Fuel
- Natural Gas
- Home sized for
- 3,000 sq ft
- Electrical service
- 200 amp
- Transfer switch
- 200 amp
- Load management
- Managed Whole House
EV charger
- Charger
- Customer Supplied GM Model # PowerUp Level 2 Charger
- Charging port
- CCS (J1772)
- Circuit breaker
- 60 amp
- Charging stations
- 1
- Estimated range added per hour
- Estimated Range Per Hour: 36 mi / 58 km
Questions from Manasquan homeowners
Standby generatorWhat size standby generator does a Manasquan home need?
The correct size is decided by the electrical loads the generator is expected to run, not by the square footage of the house. Central air, heat pumps, electric heat, well and sump pumps, refrigerators and freezers, electric ranges and dryers, pool equipment and EV chargers all count. Where a load is connected automatically, the generator either has the capacity for it or an approved load-management system controls it.
EV chargingHow much driving range does an hour of home charging add?
ChargePoint publishes estimates for Home Flex ranging from roughly twelve miles an hour at its 16-amp setting to about thirty-seven at its highest, and Tesla advertises up to roughly forty-four miles an hour for compatible vehicles on a Wall Connector. Those are estimates: the real figure depends on how efficient the particular car is.
Standby generatorCan the generator stay connected during a pressure test?
The machine has to be protected from test pressures beyond what its fuel controls are built to withstand. The fuel-gas code sets out when appliances are disconnected or isolated for testing, and the plumbing contractor follows both that code and the generator's installation instructions.