IEM Blog

Understanding the Differences in On-Site Power Systems

Thursday, May 03, 2018

on-site power

Electricity is a simple, easy to understand need. You need it to keep the lights on, run your equipment, and keep your employees and customers safe and happy. Everyone intuitively understands how important electricity is for your business, no matter what your business happens to be.

Meeting your need for electricity is far more complex than understanding why you need it in the first place. Between your primary power source, a backup system for emergencies, and other sources to meet unforeseen needs, it can suddenly become difficult to keep track of what everything does and why you need it.

Emergency Standby

Emergency Standby systems are some of the most straightforward and easy to understand. They typically consist of one or more generators with an automatic starting system and a transfer switch to connect the generator(s) to the load.

Prime Power

Prime Power systems are relatively simple. They provide all the power for a given installation and there is no normal connection with commercial power. In some cases, the utility might serve as emergency standby to the on-site prime power system.

Base Load

Base Load systems use the on-site power generation equipment to provide for the constant, essential, and continuous loads. If your facility needs consistent power over a long period of time, you’ll be using a base load system of some kind.

When increased electricity is needed, commercial power is imported to handle peak and variable loads.

Peak Shaving

Peak Shaving applications use the on-site power generation equipment to handle variable loads above a given maximum level or peak. This helps your facility avoid costly “demand” charges from the utility company.


Co-generation systems may use the electrical power in any of the above arrangements and they recover useful heat energy from the prime mover’s exhaust and cooling systems.

This heat may be used directly in a manufacturing process, space heating and air conditioning, or to drive additional electric generating equipment.

Resource Recovery

Resource Recovery systems capture an otherwise wasted fuel source such as landfill or digester gases to run electrical generating equipment. Generated power is used to run the plant itself with surplus power being exported to the commercial grid.

Learn More

IEMPS specializes in the design and build of power control systems for low and medium voltage paralleling switchgear. We have been a leader in complex and innovative applications where custom design and engineering are required. If you’re ready to upgrade your current on-site power systems or add new ones to your facility, we can help.

Read more about the on-site options we can offer in our free brochure and contact us today to get started.

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