Backup Power Planning for Greenwich Homes

When the Lights Go Out in Greenwich

When storms roll through Greenwich, comfort and safety often come down to how well you’ve planned ahead. Coastal weather, nor’easters, and the occasional tropical system can turn a quiet evening into a multi-day outage. If you’re thinking about adding a standby generator or battery backup, you’ll want a system that’s safe, quiet, and properly installed for your property.

This guide walks you through how to size your system, choose the right fuel, locate equipment safely in flood-prone areas, handle permits, and organize your documentation for future resale.

Let’s get started.

Why Backup Power Matters Here

Living on the coast means we face winter storms, high winds, and occasional flooding that can disrupt power for days. Certain areas of Greenwich also fall within FEMA flood zones, which adds extra care when it comes to siting and elevating equipment. Before you plan, it’s worth checking your property’s specific flood risk using the FEMA Flood Map Service Center.

Most homes here are served by Eversource for electricity. Natural gas availability varies by street, so confirm service and meter capacity before committing to a gas-powered generator. Eversource offers helpful guidance on backup systems, and your licensed electrician can coordinate details directly with them.

Permits and inspections are managed by the Town of Greenwich Building Division and the Greenwich Fire Marshal, both of whom outline current requirements on the town’s website.

Decide What You Want to Power

Your first step is deciding how much of your home you want backed up during an outage. A clear load plan helps you stay right-sized—quiet, efficient, and cost-effective.

Critical-load approach: Keeps essential circuits running—like your refrigerator, lighting, internet, sump or well pumps, heating controls, and security system.

Whole-home approach: Powers the entire home using an automatic transfer switch and load management to prevent overloads.

Here’s a general guide for sizing:

• Small homes or critical loads only: about 7–12 kW

• Typical 3–4 bedroom homes (no electric heat): about 16–22 kW

• Larger homes or multiple compressors/pumps: 25–45+ kW

Motors such as well pumps and AC compressors need extra surge capacity, so a licensed electrician should complete a formal load calculation. Manufacturer tools from Generac or Kohler can provide a starting point. All wiring and transfer work must follow NEC and NFPA standards.

Choose a Fuel Strategy

Your fuel choice should balance reliability, convenience, and how long you want to be self-sufficient.

Natural Gas

• Pros: Continuous supply (where available), no refueling, automatic operation.

• Cons: Not available on every street—confirm service and meter capacity before design.

Propane

• Pros: Reliable for extended outages with the right tank size; most generators can run on natural gas or propane.

• Cons: Requires an above- or below-ground tank and scheduled deliveries. Fire Marshal rules and NFPA 58 apply.

Battery Storage

• Pros: Silent, emission-free, and seamless switchover. Can pair with solar for longer resilience.

• Cons: Best for essential loads or shorter outages. Whole-home systems can be costly. Many homeowners now choose a generator + battery hybrid, letting the battery handle surges while the generator provides long-duration power.

Diesel

• Pros: Excellent for sustained heavy loads.

• Cons: Rare for single-family homes due to storage, emissions, and fuel aging.

If your home is in a flood zone, site tanks and batteries above the Base Flood Elevation (BFE) when possible. And before major storms, always confirm fuel deliveries.

Siting Equipment on Coastal Properties

In Greenwich’s low-lying areas, elevation and anchoring matter. FEMA recommends installing generators, transfer switches, tanks, and batteries above the BFE or properly floodproofed per local code. You can build an elevated pad, use pylons, or select the highest practical point on your lot.

Other key considerations:

• Setbacks and screening: Follow required distances from buildings and property lines.

• Noise: Choose a low-decibel model and position it to minimize sound for neighbors.

• Exhaust safety: Vent exhaust away from windows and adjacent properties.

Transfer Switches and Safety

A transfer switch isolates your home from the grid during outages so your generator runs safely. Automatic switches are standard for whole-home systems and are increasingly common for partial coverage too.

Eversource may require notification or inspection before connection—your electrician will handle those steps and ensure full NEC compliance.

Permits and Inspections in Greenwich

Expect several coordinated permits and inspections along the way:

• Building permit – pad and structural work

• Electrical permit – wiring, ATS, interconnection

• Gas or plumbing permit – fuel lines

• Fire Marshal review – tank placement and safety

• Floodplain development permit or variance (if applicable)

• HOA approval (if required)

Each stage—from groundwork to final inspections—takes time. Allow several weeks to a few months, depending on the town’s schedule and your contractor’s availability. Start with the Town of Greenwich Building Division for checklists and current requirements.

Choose the Right Team

Work with licensed electricians and plumbers experienced in standby power and coastal installations. For battery systems, use manufacturer-certified installers who understand residential storage requirements under current NEC codes.

Ask about prior flood-zone projects, formal load calculations, and utility coordination experience.

Maintenance and Resale Readiness

A properly permitted and maintained backup system adds real value and peace of mind—especially for buyers who work remotely or rely on uninterrupted power for comfort or medical needs.

Keep a binder (digital or physical) with:

• Permits and inspection certificates

• As-built drawings

• Fuel system documentation

• Warranties and maintenance logs

• Transfer procedures for your ATS and generator

This organization not only reassures future buyers but can also simplify insurance discussions. Some carriers even offer discounts for standby power systems—ask your provider.

Your Simple Planning Checklist

1. Check your risk: Review FEMA flood maps for your property.

2. Confirm utilities: Check Eversource and natural gas service.

3. Define coverage: Essentials only or whole home?

4. Size your system: Use manufacturer tools, then confirm with an electrician.

5. Select fuel: Natural gas, propane, battery, or hybrid.

6. Plan your site: Elevation, setbacks, and noise considerations.

7. Secure permits: Coordinate with the Building Division and Fire Marshal.

8. Hire experienced pros: Choose licensed, insured contractors.

9. Install and inspect: Complete in stages with all sign-offs.

10. Document and maintain: Keep records for service and resale.

Coastal Resilience Tips

• Elevate all equipment in flood-prone areas.

• Plan propane deliveries early, especially before storms.

• Consider a generator-battery hybrid for efficiency and quieter operation.

• Explore Connecticut DEEP resources on coastal resilience for broader preparedness.

Let’s Create Your Plan

If you’d like a personalized, discreet consultation to design a backup power plan that fits your home and lifestyle—and supports your long-term property value—reach out anytime.

Let’s connect — I’ll help you plan with confidence and calm.
— Brid Mortamais