When Should You Replace Your Generator?

Determining the right time to replace a generator can be a daunting task. For example, a standby generator is one piece of equipment in a business that feels somewhat redundant—it’s a contingency plan. Until that is, the power goes out, and it is the lifeline to keeping your business functioning or providing critical safety functions. Consider the following:

Taking Your First Step

The first step in safeguarding your business is evaluating your current system and then trying to reach a consensus on the life of a generator/engine, which can be pretty daunting. Let’s consider:

  • What is the condition of the engine, and controls?
  • Have there been any significant maintenance issues ?

So Which Type Do I Have?

  • There are two types of generators, “stationary” and “portable.” Either can be used as backup (standby) power.
  • A stationary generator is nearly ALWAYS used in a backup/standby capacity because day in and day out, the facility it is installed next to gets its power from the grid. At CD & Power, we sell, install, and service these.
  • When someone uses the term “standby generator,” they’re likely referring to an installed / stationary generator
    “Portable generators” are, as they sound, on wheels and easily transported. This is what CD & Power rents (but also sells and services)
  • “Backup” generator and “standby” generator are synonymous, referring to how the generator is used. Either of the two types of generators above can be commissioned for use as a standby/backup generator, meaning its job is to sit idle and just be serviced, exercised, and tested periodically to be ready to provide power during an outage.

Determining the equipment usage

Some engines can go as high as 30,000 hours before experiencing significant difficulties. For most of us, we gauge usage in miles and not hours so converting hours to miles is helpful in trying to determine replacement intervals for more heavily used equipment. However this is a very subjective measurement. Estimates for the conversion can be as low as one hour equals 33 miles, and as high as one hour equals 60 miles. So as an example, if you have 1250 hours on your generator, that would equate to somewhere between 41,250 and 75,000 miles.

Engine life for liquid-cooled 1800rpm engines can approach 20,000 hours if adequately serviced, depending on the application and environment

Even 3600rpm diesel engines typically have a 10,000 to 12,000-hour life expectancy with proper maintenance and service.

What is the impact of air quality regulations today and in the future?

How does a generator impact your overall CARB (California Air Resources Board) and or EPA footprint? What are the emissions now vs. the emissions of the new engine?  This is especially relevant for portable generators and fleet averaging. Changing out one high emitting generator can be just enough to get your fleet compliant.

Note: Many 30kw generators that were manufactured before 2000 have engines that are over 50hp. Most generators that are 30kw that are manufactured today have engines that are under 50hp and don’t fall under air quality requirements.

How long will the manufacturer offer support for parts?

The time range for parts support varies from manufacturer to manufacturer. It can be as little as five years for smaller manufacturers to 30 years for more prominent manufacturers. The older the generator/engine, the greater the chance that the part has been resold or repackaged, even discontinued.

Is the generator oversized or undersized?

Running a generator with a light load can lead to carbon build-up in the engine and eventually cause damage to the engine. In addition, it can cause you to have emissions that are out of compliance and expose you to fines from air quality. Running a generator with too heavy of a load can have several implications. You can cause damage to equipment that the generator is powering due to the voltage/frequency drop. There can also be damage to windings from overloading wires. Most generators have a breaker to help lessen the chances of significant component failures due to overloading.

  • Was the generator installed correctly in the first place?
  • Will a new generator require a new cement pad, new conduits, or fuel lines? 
  • Costs for removal and installation should be factored into the budget process.

Diesel vs. Gasoline

Diesel engines have a distinct advantage in longevity over their gasoline counterparts. Mechanical parts wear out over time due to the friction caused by parts rubbing together. Diesel engines, however, are engineered and built to be more robust due to the higher compression ratio in the combustion chamber and the high torque output they produce. Diesel engines also operate at lower speeds (rpm) than gasoline engines, which means the bearings, piston rings, cylinder walls, valve train don’t rub together as often. Engine speeds are often half that of a gasoline engine.

At CD & Power, we offer turnkey generator maintenance and installation services. We are the largest independent generator service provider in Northern California. Call us today (925) 690-1496 and let us show you how we are “Powering your Success.”

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