On the First Coast, your fuel is decided by which county you live in
Most regions have one gas utility and one simple answer. The First Coast has at least five overlapping ones, and the practical result is that the fuel behind your standby generator changes from county to county, sometimes from subdivision to subdivision. This patchwork is unusual enough that it should lead the whole conversation, because it settles your fuel choice before preference ever enters into it.
Here is how the map actually breaks down. JEA pipes natural gas across much of Duval County, so a large share of Jacksonville homes already have a gas main at the street. On Amelia Island, gas service comes from Florida Public Utilities (FPU) rather than JEA, a different provider for a different corner of the region. Cross into Clay County, though, and the picture flips: Orange Park, Fleming Island, and Middleburg sit largely on Clay Electric co-op territory with no natural gas main running down most streets, so those communities are propane country by default. Meanwhile a newer master-planned community like Nocatee, in St. Johns County, was built gas-ready from the start, so many of those homes have a line waiting at the lot. If you want the two fuels compared feature by feature, the natural gas vs. propane guide does that. This page is about the setup work and what that county-by-county reality means for your address.
Clay County and propane country: the on-site tank
For the many First Coast homes with no gas main, propane is not a fallback but the standard, and across Middleburg, Fleming Island, and much of Orange Park that describes street after street. An above-ground LP tank in the yard feeds the generator with a supply the homeowner owns outright. It leans on neither the electric grid nor a buried gas line a storm could disturb, and the tank is full until it is burned.
Runtime is a direct function of tank size:
- A larger tank buys days of unattended running. As a rough guide, a whole-home unit at partial load can run roughly a week or more on a 500-gallon tank, which is why that size shows up so often for full-home backup. Matching that to your loads is worth reading beside how to size a home standby generator.
- Smaller 100 or 250-gallon tanks cost less and take less yard, but they need a refill sooner in a long outage.
- The right size depends on the generator’s output, how much of the house it carries, and how long area outages tend to run.
There is a Clay County wrinkle worth naming. Middleburg and the low ground along Black Creek flooded badly during Irma, and when roads go under, the propane delivery truck cannot reach a tank that ran low. The lesson is to size generously and top the tank off ahead of a named storm, not after it passes.
JEA, FPU, or a gas-ready Nocatee lot: the utility line
Where a natural gas main runs down your road, whether it is JEA in Duval, FPU on Amelia Island, or the line already stubbed to a Nocatee lot, gas is the low-maintenance choice day to day. Nothing to fill, and as long as the main holds pressure, nothing to run dry. On a gas-ready Nocatee build the connection is often the simplest version of this job, because the infrastructure was planned in.
Tapping that line for a generator is more involved than it looks, though:
- Line sizing. A 22 kW generator at full tilt can call for roughly 280,000 to 350,000 BTU per hour, so the pipe has to carry that on top of the water heater, range, and anything else already on the system.
- Meter and regulator capacity. A standard residential meter feeding existing appliances can be maxed out the moment a generator is added. JEA or FPU may have to upsize the meter or the regulator before the unit runs reliably, and that coordination is part of the job.
- Distance and pressure. A long run from the meter to the generator pad often needs a larger diameter, or the unit starves at the far end.
Because of all that, a natural gas hookup is a permitted job for a licensed pro, not a weekend project.
Placement, flood set, and the permit
Fuel setup is not only about the fuel. Where a tank, a meter, and the generator may sit is shaped by local rules, and along the St. Johns River and its tributaries that means flood elevation. On lots that took water during Irma, Matthew, or Ian and Nicole, equipment often has to be raised above the flood set, and tank placement carries its own setbacks. Gas and tank work is permitted and inspected, and requirements shift across Duval, Clay, St. Johns, and Nassau, so the sizing, the placement, and the permit get worked out for your specific address rather than off a template.
How fuel ties into the rest of the system
Fuel never stands alone. It has to match the generator and the switch, so it is spec’d as part of a full generator installation alongside the automatic transfer switch. On propane especially, ongoing maintenance earns its keep, since a tank that quietly runs low or a regulator that drifts will leave a house dark at the worst possible moment.
Get matched with a licensed installer
River City Generators is a resource, not a contractor. Share your city and whether you have a JEA or FPU main at the street, a gas-ready lot, or would need a propane tank, and you will be connected with the one vetted, licensed local installer serving your area to size the fuel side correctly for your address. Start from the home page whenever you are ready.