PacB Group // Commercial Generators: Powering Critical Infrastructures and Industries

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Commercial Generators: Powering Critical Infrastructures and Industries

In essence, commercial generators consist of an engine, a fuel tank, a voltage regulator, some form of engine speed control, and a starting mechanism, typically a battery and starter motor. Early designs consisted of two distinct components – a dynamo, in the case of direct current (DC) output machines, or an alternator, in the case of alternating current (AC) output units, and a separate engine that powered them.

Modern commercial generators as we now know them are integrated designs and are also called gensets. These units incorporate the engine into the generator to form an individual, unitary machine. Diesel generators are the most encountered machines today, especially in the larger-capacity units. Commercial generators are ubiquitous where grid power is absent or unreliable and come in a vast variety of sizes and configurations. Commercial generators are also found where continuity of supply is critical, for example, at medical and communications facilities where they provide backup power in the event of grid failure. Diesel is not the only fuel option. Generators can be powered with petrol or some other combustible fuel source, such as piped natural gas or propane, for instance.

 

Commercial Generators as Opposed to Industrial Generators

Industrial generators work in the same way as commercial generators, but commercial generators are usually not designed to be as robust. Industrial units may need to operate in harsh environments. Generators for mining applications, for example, may operate in very dusty conditions, and require enhanced air- and fuel-filtering components. The distinction between commercial and industrial units is, therefore, not necessarily a matter of size. Commercial generators, and their more rugged industrial counterparts, are typically fueled by diesel, fuel oil, or natural gas. These engines, designed for large-capacity generators, feature robust engine blocks to handle the substantial power they can generate.

In 2015, Kawasaki Heavy Industries, Ltd. delivered an 18 MW diesel power generator to the Okinawa Electric Power Company, Incorporated, representing the world’s largest single, medium-speed, diesel power-generation system. The generator is powered by a medium-speed, four-stroke diesel engine. Companies such as General Electric produce high-speed commercial generators fueled by diesel or gas that range in size up to 40 MW. Commercial generators are often connected in parallel to achieve utility-scale output.

 

Commercial Generators from Small to Substantial

Commercial generators tailored for smaller applications may also be used by residential users. They typically range in capacity from 8 to 30 kW and are suitable for applications, such as small retail outlets, offices, and homes. Generally, a 40 kW or larger unit is categorised as a commercial generator. For commercial and industrial entities, gensets usually range from 40 kW to 2,200 kW, intended for use in office complexes, factories, and various industrial facilities. A 2.2 MW genset can be conveniently accommodated in a 12 m shipping container, inclusive of controls, fuel tank, electrical power distribution gear, and all necessary components to function as a standalone power station or a standby backup solution.

These gensets, known as power modules, are trailer-based, facilitating easy mobility from site to site. They can be combined in parallel to form small power stations, with 1 to 20 units per section, or installations may involve hundreds of power modules, creating utility-scale, power-generating plants. In large commercial solutions, the power modules (engine and generator) are transported to the site on trailers and interconnected to establish a fully synchronised power plant.

 

Single Generator or Several Smaller Units in Parallel?

At sites where power requirements are substantial, one of the decisions to be made is whether to opt for a single, large commercial generator or to distribute the load among two or more smaller units. For instance, instead of deploying a single 2400 kW commercial generator, one could use three 800 kW units. This strategy, known as paralleling, can be the preferred choice in certain circumstances. Paralleling introduces greater flexibility, while a single unit lacks redundancy.

With multiple generators, if one unit fails or requires maintenance, the load can be seamlessly shifted to the other units, ensuring uninterrupted operation and continuity of electrical power supply. Paralleling may even offer cost advantages. Generally, generators above a certain capacity become less economically viable than smaller units paralleled up to deliver the same power. In addition, relying on a single, larger unit provides no redundancy. The threshold at which larger units become less economic correlates with the point at which the generator requires an engine larger than those that are mass-produced for applications other than generators, such as engines found in trucks, earthmoving equipment, and ships. Truly massive engines are produced in limited quantities and cost considerably more than mass-produced engines do. Given that the engine constitutes over half the cost of a generator, minimising the engine cost makes the whole generator less costly.

 

The Best Fuel for Commercial Generators

While diesel fuel has long been seen as the conventional choice for commercial and industrial standby power, it is not the exclusive option. Natural gas is an alternative but has historically been considered less desirable for commercial and industrial applications due to cost, power-density concerns, concerns about engine durability, and fuel supply reliability. However, advancements in engine technologies, enclosures, and other generator components have blurred the distinctions between diesel and natural gas-powered units to a large degree.

Diesel has traditionally offered several advantages over other fuels. It is considered a reliable fuel supply that is not susceptible to disruptions in the supply pipeline. Additionally, diesel generators are typically lower in cost than their natural gas-powered counterparts. Diesel engines in gensets generally require less maintenance than other generator types. Diesel is also less flammable than some alternative fuels, making it relatively safe to store and easier to clean up in case of a spill.

On the other hand, natural gas may eliminate the need for fuel storage in areas where it is delivered through a piped gas system. Natural gas has also proven to be an extremely efficient and clean fuel source, with nearly odorless exhaust emissions. Natural gas-powered generators are renowned for their quieter operation compared to diesel units. Although commercial generators running on natural gas often incur higher initial costs than their diesel counterparts, the investment can be justified in certain areas. The decision between diesel and natural gas usually hinges on the availability and cost of piped natural gas.

 

Speak to the Specialists in Commercial Generators

We at PacB are widely recognised in the power-generation industry for producing high-quality commercial generators. When it comes to selecting high-capacity diesel generators, a considerable level of technical expertise and experience is essential to ensure the correct solution is purchased and installed. At PacB, we understand generator sizing, fuel types, and generator integration. These factors must be meticulously aligned with the specific conditions and requirements at the intended installation site.

Our team of talented engineers and technicians excel in the design and manufacturing of generators and their control systems. Our team can design and manufacture Synchronous PLC controlled panels for multi-station generator supply across a broad spectrum of sizes and voltages, including systems exceeding 1000 kVA. Contact us today for anything related to commercial generators.