Choosing the Right Size Generator Rental for Your Emergency Power Needs

January 04, 2024 · Leave a comment · Red-D-Arc Welderentals
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Planning for emergency power outages due to weather, brownouts, or natural disasters by using a generator rental can save your business thousands of dollars in lost revenues. However, to get the most out of your generator, you need to choose the correct size and type for the job.

The Importance of Choosing the Right-Size Generator

Cost-conscious business owners may be tempted to try to get by with an underpowered generator to save money, but this is not a good idea. Using the wrong size generator can damage both the generator and the equipment that is being powered by it, which can end up being more expensive than renting the correct size generator in the first place. When estimating your emergency power needs, it is better to choose a generator based on the high end of your estimate for several reasons:

  • The generator will last longer
  • Less chance of capacity overload
  • More consistent performance
  • Reduced chance of system failure
  • Lower risk of damage to equipment
  • Less likely to cause electrical fires or overheating
  • Safer for personnel
  • Maintenance is easier, faster, less frequent, and less expensive

generator rental fleet at Red-D-Arc Ontario Rental Center

Sizing Your Generator

The best place to start when determining the size of generator rental you need is to compile a list of everything the generator will need to power during an emergency outage. This list should include lighting, heating and cooling systems, office equipment, heavy machinery, and anything else you need to continue running to keep your business functioning safely and efficiently.

Once you have your list, record the wattage needed to power on and to run each item on your list. You can find this information printed on the equipment somewhere, but it may help to consult with an electrician or the equipment manufacturer. Add up all of these numbers in kW or KVA units to determine your total power needs. If you have equipment rated in amperes, use a formula to convert amps to watts:

  • Resistive loads: Wattage = amperes x volts
  • Reactive loads: Wattage = amperes x volts x load factor
  • If you do not know your load factor, it is the ratio of electric energy use in kilowatt-hours to peak demand in kilowatts. Using information from your electric bill, you can calculate the load factor by using the formula:
  • Previous month’s total kWh / (current period peak demand x 30 days x 24 hours)

If you can not find wattage information printed on your equipment, try checking the manual. If you can not find the manual, then look for information on the manufacturer’s website. If you’re still having trouble, you can look up an estimate online for many equipment types.

Now that you have your estimated total wattage, you should choose a generator that has 10-20% more capacity than your estimate. This will provide you with extra capacity to cover underestimation of your requirements, under-performance of the generator, or equipment upgrades that may require more power.

Effect of Generator Size on Cost

More powerful generators will usually be more expensive to purchase or rent, but you also need to consider fuel costs. The larger your generator is, the more fuel you will burn. Calculating your estimated fuel usage is important for estimating cost and ensuring you have enough fuel stored on-site to keep your generator operating during an emergency.

emergency power generator on a flood remediation job

Be Prepared for an Emergency

You do not want to wait for a disaster to occur to scramble to find an emergency generator rental. Contact the team at Red-D-Arc today to discuss your generator needs. You can reach us by phone at 1-866-733-3272, fill out our online form, or click the “get a quote” button by the piece of equipment you are interested in to get started.


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One comment
  1. Power outages can happen at any time. Whether it’s during a blizzard in the winter or a storm during hurricane season, extreme weather often leads to power outages. There’s not a whole lot that you can do to prevent them, but there are steps you can take in order to be prepared

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