Do I Need Both A UPS And A Standby Generator?

A UPS and a standby generator often work together to provide reliable backup during an electrical outage or disruption to the mains supply. A UPS provides immediate power from its batteries or other stored energy, while a generator can supply power for an extended period.

Whether you require both depends on how critical your IT equipment or machinery is, how long it needs to remain operational, and the consequences of any power disruption.

A UPS bridges the gap while a standby generator starts and transfers the electrical load, helping to prevent equipment from losing power during the changeover. If the generator fails to start, the UPS can also provide sufficient backup for an orderly shutdown, depending on its remaining battery capacity.

UPS systems can also protect the connected equipment against certain power quality problems, such as voltage sags or surges. The level of protection depends on the UPS technology and operating mode.

Combining a UPS with a generator is particularly beneficial in environments where power continuity is absolutely essential, for example, mission-critical environments including data centres, hospitals, financial institutions and industrial facilities. The UPS supports sensitive electronic equipment, while the generator helps maintain operations during a prolonged mains failure.

Standby generators mainly run on diesel or gas, although other fuels are available. The available runtime depends on various factors, including fuel supply, generator size, and electrical load. Diesel installations may use additional external fuel tanks to extend their operating autonomy.

When designing a combined system, it is important to ensure that the UPS and generator are correctly sized and compatible. Generator starting characteristics, load changes, power quality, and the UPS’s recharge requirements should all be considered too.

In summary, a UPS and generator serve different but complementary purposes: the UPS provides immediate continuity and power protection, while the generator provides longer-duration backup. Together, they can form a robust power protection solution for critical equipment and operations.

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