Connecticut storms — the nor’easters, the tropical remnants, the ice storms that show up in March — have a way of clarifying what backup power is actually worth. After a week without power in 2011 from Tropical Storm Irene, or the October snowstorm that followed two months later, a lot of Connecticut homeowners made a decision: a standby generator is not a luxury.
If you’ve bought a generator or are about to, the most important thing to understand is this: the generator itself is just the box. What makes it work safely and legally is the electrical hookup — the transfer switch, the dedicated circuit, and the permits. That’s the part we handle.
The Misconception We See Every Year
Every storm season, we talk to homeowners who believe that once the generator is delivered and the gas line is run, they can just “plug it in.” That’s not how standby generators work — and attempting it creates a serious safety problem called backfeed.
When a generator is connected to your home’s wiring without a transfer switch, it can push electricity back through your meter onto the utility lines. Those lines are assumed to be dead by utility workers making repairs. Backfeed can kill a lineworker. It can also damage your generator, your appliances, and your panel when utility power is restored while the generator is still running.
This is why transfer switches exist, why Connecticut requires them, and why the electrical hookup is not a DIY project.
What We Actually Do
Our scope of work on a generator installation covers the electrical connection from your electrical panel to the generator. Specifically:
Transfer switch or interlock kit installation — This is the core of the job. The transfer switch disconnects your home from the utility grid before the generator is connected, preventing backfeed. An interlock kit achieves the same isolation through a mechanical device that prevents the main breaker and generator breaker from both being on at the same time.
Load calculation — We calculate your electrical loads to determine how the generator should be configured and which circuits are covered under the generator’s capacity. A whole-house generator runs everything; a partial-load setup covers the circuits that matter most to you (HVAC, refrigerator, lighting, well pump).
Dedicated circuit — The generator connects to your panel through a dedicated circuit sized for the generator’s output.
Utility notification — Connecticut utilities (Eversource, UI, and Wallingford Electric) require notification when a connected generator is installed. We handle this as part of the job.
Permit — Required by Connecticut law for this type of work. We pull it before the job starts.
Transfer Switch vs. Interlock Kit
Both accomplish the goal of safe isolation. Here’s the practical difference:
Automatic Transfer Switch (ATS) An automatic transfer switch monitors utility power and automatically switches the home to generator power when it detects an outage — typically within seconds. When utility power is restored, it switches back and shuts down the generator. No homeowner action required. This is the premium setup and what most Generac, Kohler, and Briggs & Stratton standby generators include in their package.
Manual Transfer Switch Similar to an ATS but requires you to manually flip the switch when the power goes out. Less convenient, less expensive. More common with portable generator setups.
Interlock Kit A mechanical device mounted on your existing panel that prevents the main breaker and generator backfeed breaker from both being energized at the same time. It’s a code-compliant, lower-cost alternative to a full transfer switch — particularly common for whole-house standby setups where the generator capacity exceeds what a smaller transfer switch panel would cover. We can walk you through which makes sense for your specific setup.
What We Don’t Do
We want to be clear about our scope, because generators involve multiple contractors:
Propane and natural gas line work — The fuel line from your propane tank or gas meter to the generator is the work of a licensed plumber or gas contractor. We coordinate timing so the electrical and gas work are sequenced correctly, but we don’t run gas lines.
Generator servicing or repair — Standby generators need annual maintenance — oil changes, filter replacement, load testing. That’s manufacturer service or an HVAC/mechanical contractor, depending on the generator. We don’t provide generator maintenance or repair.
Generator purchase or delivery — We work with any generator brand: Generac, Kohler, Briggs & Stratton, or others. You source and arrange delivery of the generator; we handle the electrical hookup.
Permit Requirements in Connecticut
Almost every generator installation in Connecticut requires a permit — specifically an electrical permit for the transfer switch and circuit work. In most towns, a building permit is also required for the generator pad (the concrete or composite pad the generator sits on).
We pull the electrical permit. The concrete pad permit may need to be pulled separately by your contractor or general contractor, depending on the town. We flag this during the estimate so there are no surprises.
Some towns also require notification to the fire marshal for propane-powered generator installations over a certain size. We’ll tell you if your town is one of them.
Timeline: How Long Does the Electrical Work Take?
For a straightforward whole-house standby generator installation where the gas/propane line is already in place:
1 day for the electrical work — transfer switch installation, panel work, dedicated circuit, permits in hand.
What can extend that:
- Service entrance work needed at the same panel visit
- Panel upgrade required to support the generator’s electrical demands
- Utility scheduling for service disconnect if panel work is involved
- Multiple sub-panels that need to be addressed for the generator circuit
If the gas line isn’t in place yet, the electrical and gas work need to be sequenced. We can do the electrical rough-in while the gas work is in progress, then complete the final connections once everything is in place.
Cost Range for the Electrical Hookup
Generator electrical installation costs in Connecticut range significantly based on the complexity of the transfer switch setup, the generator size, and whether panel work is needed:
$3,000–$6,000 — Standard whole-house automatic transfer switch installation for a 20–22kW generator, typical residential panel, no additional panel work needed
$6,000–$10,000 — Larger generator, more complex load calculation, subpanel involved, or panel upgrade at the same visit
$10,000–$15,000+ — Large whole-home setups with 400A service, multiple sub-panels, significant load management work, or commercial-adjacent residential applications
These are electrical hookup costs only — the generator itself is separate hardware ranging from $3,000 to $15,000+ depending on brand and size.
Brands We Work With
We install the electrical infrastructure for any brand of standby generator. The brands we see most often in Connecticut:
- Generac — the most common residential brand; wide service footprint, parts widely available
- Kohler — strong residential and light commercial options; excellent quality
- Briggs & Stratton — solid residential line, now marketed under Standby Power brand
- Cummins — more common in commercial applications but available for residential
Brand recommendation isn’t part of our job — that’s between you and the generator supplier. We make any brand work on the electrical side.