3 Simple Steps to Take When Planning for Temporary Power

Electricity is never more precious nor more scarce than after a disaster. Lights are out, telephones disabled, businesses shut down. People may need food, water, heat and medical attention. There can be no real recovery without power, yet no one can predict when utility service will come back.

Although critical, planning for power doesn’t need to be difficult. Here are three simple steps that will help you secure and maintain the rental power necessary to carry your facility successfully through a scheduled or emergency shutdown:

  1. Determine your facility’s electrical load

    Before you rent temporary power, you have to know how much you need. There’s two main options:

    • Full Power:
      If you have to keep your whole facility operating as it would with utility-supplied power, you need to determine your aggregate electrical load. The quickest, easiest and most accurate way to do this is to take ammeter readings of your electrical distribution boxes. Take the reading when your company is normally operating at peak load. You may also be able to obtain peak demand readings from your utility bills. Aggregate loads are also listed on panels of electrical distribution boxes.

    • Priority Power:
      At times, you may want to power only those electrical loads that serve critical functions at your facility. If so, you need to prioritize individual loads.

      If you’re not sure what your critical loads are, start by determining the lost profit or other problems that result if your company is without the equipment. Other than life-safety electrical loads powered by your standby generator sets as required by law, examples of critical loads include: 

      • Lights
      • Heating, ventilating and air conditioning (HVAC)
      • Computers
      • Process Equipment
      • Pumps

      Prioritizing will help you decide which loads require power immediately during an emergency. This is important since it may take several hours or longer to secure all of the rental equipment you need onsite during a large scale emergency, such as a natural disaster.

      In most buildings, a separate distribution box will feed critical loads. In this case, you may only need enough temporary power for the loads served by that set of circuit breakers.

      You can also decide to power specific critical loads served by separate circuit breakers within a distribution box. To do so, take an ammeter reading of the distribution box during the off-hours at your facility with the equipment you don’t need shut off and the critical loads on. The ammeter will tell you how much power you need to serve the critical loads since that is all the distribution box is feeding. However, it’s important that the non-critical loads are shut off and kept off when rental power is hooked up.

      If you want to power individual pieces of equipment that use motors, amperage and voltage information is listed on nameplates. You can list this information and all your power needs on the worksheet in this booklet.

      An additional note: Rental power is often used to back up standby generator sets during scheduled and emergency outages. To find out how much temporary power you need for standby service, contact the company that supplied the standby generator, or a qualified rental generator set dealership.


  2. Know where to rent generator sets and related equipment

    Your rental generator sets are only as reliable as the supplier who backs them. In planning for temporary power, find a rental dealership that has the equipment you need, and a staff qualified to solve your problems and service the machines. Visit the dealership to get to know the people you’ll need to rely on during scheduled shutdowns and emergency power outages.

    Supplier selection criteria could include:

    • Inventory –The supplier should have all necessary equipment in stock – generator sets and accessories – or be willing to commit to getting it on demand. Suppliers who do not have the equipment available in the region must have the capability to import it in an emergency.

    • Service and support –The supplier should be willing to deliver the power generator sets and, in some cases, additional equipment including power cable, transformers and more. In addition, suppliers should train local personnel in the equipment operation or, if necessary, provide staff for operation, service and maintenance.

    • Location – At a minimum, the supplier should be strategically located to serve major population centers. The ideal supplier will have multiple locations from which to deliver equipment and dispatch support staff.

    • Experience – Longevity in business can be a good indicator of a supplier’s reliability. Suppliers should be willing to discuss their track record in delivering and installing equipment under tight deadlines, as well as their experience in emergencies. Reputable suppliers will always provide references.

    • Terms – When renting generator sets for emergencies, it is not always possible to secure an absolute guarantee for the availability of the equipment. However, some suppliers offer contracts that provide a “right of first acceptance.” In this arrangement, a party pays the supplier a retainer fee for an allocation of specified equipment. In return, the supplier agrees not to release that equipment to another entity without the first party’s consent.

      Some basic questions to ask include:

      • What is the kilowatt (kW) range of your generator set rental fleet?
      • Can you deliver immediately? If not, how long will it take?
      • What if I need a generator set in the middle of the night, or during a holiday?
      • Who supplies the fuel?
      • How are your rental contracts structured? How flexible are they?
      • Have you ever rented generator sets to customers in my industry?
      • What equipment/manpower do I need to provide?
      • What technical service/support do you offer?
      • How do I know my rental units are reliable?
      • What happens if a generator set I rent goes down?
      • Do you have cables and other equipment I may need?
      • Can you train my staff to hook up and operate the equipment? How long will it take?
      • Can I obtain pre-approved credit so I can avoid delay during an emergency outage?
      • Can you supply an operator?


  3. Answer the basics, save time and money


    Think about the following before the power goes off at your facility:

    • How will the generator sets get from the dealership to the facility? Most dealerships deliver, but if you pick up the equipment yourself, you need to determine what size truck you will need. Most generator sets are towed on semi-trailers and pull trailers. Others are skid-mounted and require lifting equipment for loading and unloading.

    • Where will you put the generator sets? The largest generator sets measure 8 feet wide by 40 feet long (2.5 meters wide by 12 meters long). If tight quarters are a consideration, two or more smaller units will perform just as efficiently.

    • When it comes to accessory requirements, cable must be provided to connect the generator sets to the building’s electrical system. Transformers, load banks, bus bars, distribution panels, feeder plants, fuses, outlets, load centers and other accessories may also be necessary.

    • How will you get cable from the generator sets outside your building to electrical distribution boxes inside? Consider installing a weatherhead, or a cable access door in an outside wall of your facility that can be closed when not in use. Then, you won’t need to route cable through windows and doors that should remain shut during off-hours or inclement weather.

    • Can you store enough fuel close to the area where you plan to keep the generator sets? During extended generator set runs, an auxiliary tank of fuel with capacity for at least 24 hours of run-time will reduce service calls from your fuel supplier.

    • Do you have people on staff who can hook up the generator sets and check to ensure they will operate properly? If not, make sure your dealership or an electrical contractor can do the hookup, or have the dealership walk your staff through the procedure.



    Your dealership should have people on staff to help you plan out your fuel capacity, cabling needs and onsite support.


    Download our full Rental Power Planner that includes this information, plus:

    • Useful electrical formulas
    • Key generator set features to specify
    • Power outage worksheets (Key Contact Phone Numbers and In-House Electric Info)
Rental Power Planner
Download our full Rental Power Planner to access useful formulas, key generator set features to specify, and worksheets.

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