Planning generators for events: A United Rentals guide

Power generators for events bring sound systems, video screens, stage lights, food trucks and outdoor air conditioners and fans to life. But powering an event requires careful planning and no small amount of expertise. This overview of special event power rentals spells out four key steps to successfully planning portable power for large outdoor events.

A knowledgeable temporary power partner can help with load calculations, equipment selection and power distribution planning as well as provide all the equipment needed.

Step 1: Add up your event’s total power needs

Step one is figuring out how much power you’ll need across the whole event. Start by listing everything that requires electricity, including A/V gear (microphones, speakers, video boards), food trucks, refrigerators, restroom trailers, lights and cooling or heating equipment.

Next, write down the wattage for each asset, which should be listed on the product label. If the label lists amps and volts, calculate the wattage by multiplying volts times amps. For example, a 120-volt speaker that draws 2 amps uses 240 watts (120 x 2 = 240).

To calculate the total event power load, add up the wattage for each asset. It’s common practice to include a safety margin of at least 20%. This buffer helps account for the extra inrush (startup) current required by larger equipment such as sound systems. A quick example:

• Total wattage of all devices = 12,500 watts
• 20% buffer (12,500 x .2) = 2,500
• Total wattage needed to power your event = 15,000 watts (12,500 + 2,500)

Step 2: Determine the generator sizes required

Most generators are rated in kilowatts (kW). When figuring out what size generators you’ll need, convert the total power load from watts to kW. A concert requiring 15,000 watts of energy would need at least a 15kW generator (1,500 ÷ 1,000 = 15 kW.) Keep in mind that you may need multiple generators.

Heavy-duty gear such as professional-grade AV systems, high-intensity lights and refrigeration trailers may require a three-phase generator. Three-phase generators deliver more power and a steadier, more reliable flow of electricity than single-phase units.

Step 3: Design a power distribution plan

Power distribution for events is critical. With a proper distribution system in place, one large generator can safely power a number of assets across multiple zones.

Start your power distribution plan by mapping out the event space zones—main stage, medical tent, vendor area, etc. Then work with your power equipment rental partner to figure out the best mix of power distribution equipment and where to place it to maximize efficiency.

Your partner can help you select a distribution panel—the main power hub for the event—as well as feeder panels such as spider panels and Edison panels to balance the electrical load. A knowledgeable temporary power provider can also guide you to the right cables and properly rated extension cords. Stand-alone circuit breakers can protect equipment from power surges. Transfer switches let you switch to backup generators as needed.

Step 4: Consider a battery energy storage system

For events with sustainability goals, a battery energy storage system (BESS) paired with a generator can dramatically reduce generator run time, curbing emissions as well as fuel costs. The generator recharges the BESS batteries when it runs. During lower-load periods, the BESS automatically shuts the generator off and powers the load.

Even greater emissions reductions come from pairing a lower-emission generator with a BESS. Propane or natural gas generators such as the JuiceBox produce 17% lower greenhouse gas emissions compared to diesel generators, with operating costs up to 40% less. Low-emission generators also run quieter than diesel generators.

United Rentals: Your one-stop shop for event rentals

When planning temporary power for outdoor events, the vendor you choose matters.

United Rentals not only carries an extensive selection of generator rentals for events and a full line of power distribution equipment but also excels at helping customers with temporary power planning and provides onsite support to help ensure reliable event power.

Want a turnkey power package? United Rentals can help you design a custom plug-and-play solution that simplifies installation and distributes electricity efficiently through dedicated feeds.

Also consider United Rentals for your other event equipment needs, from lights to HVAC equipment to barricades, ground protection mats and UTVs.

Reach out to our Power and HVAC team for help with special event power rentals and power distribution for events.