Temporary power rental is a generator plus everything that gets the electricity to the load. A 20 kW towable runs about $150 a day, a 100 kW set $300 to $500, and a 500 kW unit up to $1,500. Fuel, cable, distribution boxes and a transformer if your voltage differs are all separate lines, and on a long hire the fuel bill overtakes the rental.
Size to the load, not to the nameplate list
Add the running load of everything that will be connected, then account for what starts hardest: motors, compressors and lifts draw several times their running current for a moment. A generator sized only to the running total will trip on start-up. Give the supplier the equipment list and let them size it, because that is a calculation they do daily.
The kit that comes with the generator
A set on its own powers nothing. You also rent cable in the right gauge and length, distribution or spider boxes with the outlets your tools use, a ground rod, and a transformer if the site runs a voltage the generator does not produce. Each is a separate rate, and together they can approach the cost of the generator on a small job.
Fuel, run hours and the refuelling arrangement
Towable diesel sets carry enough for roughly twenty-four hours at load. Above that you are arranging refuelling, either yourself or on a scheduled fuel service from the supplier. Ask whether the rental is capped by run hours, because some agreements bill extra past a monthly threshold, and confirm whether the machine returns full or is refuelled at the yard's rate.
Day, week or the standby month
Short outage cover is a day rate. Anything spanning a project phase is priced weekly or monthly, and monthly is roughly three weekly rates. Standby hire, where a set sits on site unused against a possible failure, is normally a reduced monthly rate with run hours billed separately, so say plainly which of the two you are buying.
Questions people ask about temporary power rental
What size generator do I need for a construction site?
A small site running hand tools and lighting is comfortable on 20 to 60 kW. Add a tower crane, a pump or a temporary heater and you are at 100 kW and above. Give the supplier your equipment list rather than guessing, since motor starting is what actually decides the size.
Is fuel included in a generator rental?
Almost never. The set arrives full and either returns full or is refuelled at the yard's rate. On any hire past a couple of days, arrange a fuel service and treat it as a separate budget line.
Can a generator be delivered and connected the same day?
Delivery often, connection less often. A plug-and-play towable feeding spider boxes can be live in an hour; anything wired into a building's distribution needs a licensed electrician and, in most jurisdictions, an inspection.