Option A
Generator
A portable or towable engine and alternator, delivered, placed outside and refueled on a schedule.
- Ready
- As fast as delivery
- Needs
- Fuel, open-air placement and a sizing check
- Good fit
- Short jobs, events and sites without a line
A generator brings its own power: it arrives on a truck and runs as long as it has fuel. Temporary utility service brings the grid to the site through a pole, a panel and a meter, once the permit and inspection are done and the utility connects it. Many long jobs use both: a generator first, then the utility, with the generator kept for backup.
Option A
A portable or towable engine and alternator, delivered, placed outside and refueled on a schedule.
Option B
An electrician sets a temporary pole and panel, the work is inspected, and the utility sets a meter.
The short answer
Time on site and distance to a line settle most cases. Noise, fuel and the size of the load settle the rest.
Side by side
Cost is described by what drives it, because prices change by market and by utility.
| Question | Generator | Temporary utility service |
|---|---|---|
| Lead time | As fast as delivery | Depends on the permit, the inspection and the utility's schedule. Call the utility early |
| What the site provides | An outdoor spot with clear space around it, a firm dry surface and truck access for fuel | A pole and panel set by an electrician, inspected before the utility connects. One city requires a wooden pole at least 20 feet long, set 4 feet in the ground5 |
| Noise | Engines vibrate and make noise. Keep them as far as possible from work areas and gathering spaces3 | No engine on site |
| Fuel | Delivered on a schedule. A generator that runs dry stops the site. See fuel delivery | None |
| Emissions | Exhaust contains carbon monoxide, so never indoors. Engine emission and air permit rules can apply, especially if it stays put for a long time | No exhaust on site |
| Load sizing | The running rating has to cover everything on at once, and the starting rating the biggest motor kick. See the sizing calculator | The service size is set with the electrician and the utility for the whole site |
| Reliability | Depends on fuel, maintenance and a backup plan for a breakdown | Runs as long as the grid does. Ask which loads need backup in an outage |
| What drives the cost | Size, rental term, delivery, fuel, cords and distribution. See temporary power rental cost | The electrician's pole and panel, permit and inspection fees, the utility's connection charges and the power you use |
| Safety on a construction site | GFCI on 120 volt, 15 and 20 amp outlets, with a narrow exception for small two-wire generators1 | The same GFCI rule applies to temporary outlets1 |
Tell us what will run, for how long and where. We source generators or temporary service through local providers, schedule the fuel and send one bill.
Decision path
Stop at the first answer that settles it.
Is it an event or a job measured in days?
Is there a utility line close to where the panel would go?
The utility can tell you whether a line extension is needed and what it involves.
Do you need power before the permit, inspection and connection can happen?
Is there a load that cannot go down, such as pumps, heat or security?
Use both
The two options are not either-or. On a long build they often take turns.
A generator powers the trailer, tools and lights from the first day. When the temporary service passes inspection and the utility connects it, the generator comes off or moves to standby for loads that cannot stop.
Some things stay self-powered all along: light towers on a moving work front, or temporary heat where the service cannot reach. Never wire a generator into a building or trailer panel without a transfer switch installed by a qualified electrician.3
The rules
Federal rules set the floor. Your state, your city, your utility and your air agency can add to them.
29 CFR 1926.404 and 1926.405
On construction sites, 120 volt, single-phase, 15 and 20 amp outlets that are not part of the permanent wiring need GFCI protection, or an assured equipment grounding conductor program. Small two-wire generators of 5 kW or less with insulated conductors are the exception. Temporary wiring has to be removed as soon as construction is complete.12
OSHA fact sheet
Never run a generator indoors or in enclosed spaces, even with doors and windows open. Give it 3 to 4 feet of clear space on all sides and above, keep it away from doors, windows and vents, and shut it down and let it cool before refueling.3
U.S. EPA
EPA sets emission standards for nonroad engines and equipment. A portable engine that stays at one location for more than 12 consecutive months is no longer a nonroad engine under EPA's definition, and EPA's stationary engine rules come into view.467 Ask your state or local air agency whether a permit applies to your site.
Your city and utility
For temporary utility service, city permits and inspection come before the utility connects, and the utility sets its own pole and meter rules. One city's rules cover temporary poles for service of one year or less.5 Ask your utility and building office for theirs.
What it depends on
Neither one is cheaper or better everywhere. These are the things that tip it.
A generator is paid for by the day, week or month, plus fuel. Utility service has its setup cost up front, then the power you use.
A line next to the site makes utility service simple. Needing a line extension adds time and cost.
Big motor loads need a generator sized for the starting kick. Steady loads suit a utility service.
Someone has to schedule deliveries, and diesel exhaust fluid where the engine needs it.
Engine noise runs all day and sometimes all night. Local noise rules vary, so check them.
For a quote
We source generators or a temporary service through local providers, schedule the fuel and send one bill.
Common questions
Use a generator for events, short jobs, sites without a nearby line, and power before the utility can connect. Use temporary utility service for long builds with a line close by. Many long jobs use a generator first, then the utility.
It depends on the permit, the inspection and the utility's schedule, and on whether a line has to be extended. Ask the utility early, and plan a generator for the gap if work starts first.
Yes. OSHA requires GFCI on 120 volt, single-phase, 15 and 20 amp outlets not part of permanent wiring, or an assured equipment grounding conductor program. Two-wire generators of 5 kW or less with insulated conductors are the exception.
No. OSHA says never use a generator indoors or in enclosed spaces, because exhaust carbon monoxide can build up even with doors and windows open. Keep 3 to 4 feet of clear space around it.
It can. EPA sets emission standards for nonroad engines, and a portable engine that stays at one location more than 12 consecutive months is no longer a nonroad engine under EPA's definition. Ask your state or local air agency.
Yes. We source generators or a temporary service through local providers and schedule the fuel. Call sales at (888) 588-2607 or request a quote.
Local providers do the work; we hold the contract, own the problems, and send one bill. If a delivery gets missed, we contact the provider the same business day.
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