All machines, including the diesel engine generators, produce heat when in function. This can be a more severe issue in the case of generators as they have to work really hard to generate a huge amount of electricity. This heat increases the temperature within the generator, heating almost all of its internal parts.

Air Cooled vs Liquid Cooled Diesel Generator

To maintain this temperature, coolants are used so that the generators don’t overheat and continue to perform as they are expected to. Most commonly, generators are either air-cooled or liquid-cooled, depending on their size and make, and these coolants play an important role in their functioning.

Air Cooled Systems in Portable Generators

Liquid cooled Diesel Generator

Air-cooled generators utilize surrounding air from the atmosphere to cool down the internal parts. While the open ventilator variant of air-cooled generators uses the air from the outside for cooling and releases the hot air back into the atmosphere, the air continuously circulates inside the generator in the enclosed variants. This system makes it vulnerable to overheating and thus they are only used for select functioning.

Water Cooled Systems in Portable Generators

 Water cooled Diesel Generator

A liquid-cooled generator, on the other hand, use a specially made coolant or oil to cool down the internal parts. It mainly uses a radiator or a water pump to circulate the coolant throughout the generator, which absorbs the heat and then passes through the radiator having another round of cooling. This automatized system makes oil-cooled generators more efficient in handling heat, and that is why it is more advisable to use oil-cooled generators for commercial use.

Air-Cooled vs Liquid-Cooled Generator – Which One to Pick?

But which coolant should you prefer if you are using a commercial generator? Do air-cooled systems work well for you or do liquid-cooled systems make for a better choice for your business? Normally, air-cooled generators are small in size and are commonly used in small units and homes to supply a limited amount of electricity. But commercial generators are supposed to perform better and generate a larger amount of electricity, which is why liquid cooling is used in large-sized generators that are used in commercial, and industrial units. But why is it that liquid cooling systems are used in large units and air-cooled ones are often considered suitable only for the small ones?

Fret not! We will tell you everything about these generator types today! Simply read on about the distinctive aspects of each type of standby generator to know more and make an informed decision –


The requirements of commercial establishments are always on the higher side. They require a larger amount of power and electricity as compared to smaller establishments. And liquid-cooled generators are perfect for fulfilling such requirements. They are usually big, made of complex mechanisms, and possess the ability to generate a lot of power. This is not the case with air-cooled generators. They are more portable in size with a simple mechanism and are perfect for smaller units. Liquid cooling systems have a capacity of 15kW, and their cooling mechanism allows them to function even in extremely hot weather.

Liquid cooled Diesel Generator on sale

Noise Levels

Even though an air-cooled generator is often portable and meant to be used in smaller, and compact units, it can be extremely noisy. This can make them undesirable for homeowners. Liquid-cooled generators are a lot less noisy as their mechanism is based on the liquid being circulated throughout the generator instead of air, which creates more noise. The liquid-cooled generators, used in industrial units are mostly installed outdoors as they require a lot of space and proper installation. Despite their size, they produce lesser noise and still generate a lot of power.

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Liquid-cooled generators are designed to withstand harsh weather conditions and their bulky nature allows them to last longer and provide a more reliable service. Their sheer size ensures that their output is enough to provide sufficient power to industrial and commercial units. They are complex machines, but their efficiency makes them a perfect choice for commercial establishments.

Both air-cooled and liquid-cooled standby generators have their own pros and cons. It all depends on the usage. Air-cooled generators are smaller in size and create a limited amount of power making them a good choice for home standby generators.

However, when it comes to commercial establishments, liquid-cooled engines are ideal. This is because they are huge in size and are capable of fulfilling large energy requirements, especially during power outage. Their cooling mechanism using a coolant or oil is a lot more efficient than an air-based cooling mechanism. This is why liquid-cooled generators are able to run more efficiently while producing a large amount of electricity. A liquid cooled engine might require more maintenance as compared to air-cooled ones, but their performance is top-notch. Hence, it doesn’t come as a surprise that most commercial standby generators make use of a cooling liquid, instead of depending on an air cooled system.


Frequently asked questions about liquid cooled diesel generators

Why liquid-cooled generators are a better choice for commercial usage?

Commercial establishments usually have higher power needs as compared to smaller ones, especially homes. This is why it is ideal to install a generator that is high on performance and has a greater capacity for generating power. And liquid-cooled generators fulfill all these requirements. They are huge in size and the diesel engine variant can produce electricity up to 15kW. Their efficient cooling mechanism, which uses a coolant or oil circulating throughout the engine, supported by a radiator and a fan, makes them extremely efficient in managing extra heat produced within the generator. This keeps the temperature under control and makes them perform well.

What are the advantages of a liquid-cooled diesel generator?

There are several advantages of liquid-cooled generators. They are perfect for large, industrial establishments. They are durable and provide excellent performance. They are powerful, efficient, and effective. They produce less noise as compared to air-cooled generators, and they can be used for 10,000 hours without any major disruption. They can work efficiently even in harsh, and hot weather. These advantages make them perfect for heavy-duty usage.

Are liquid-cooled diesel engine generators more durable and long-lasting?

Yes, liquid-cooled diesel engine generators are more durable and long-lasting because of their ability to control the heat more efficiently. The coolant or oil runs through the system absorbing heat. The liquid then passes through the radiator, where it is cooled with a fan blowing air on it. This not only manages the heat better but also keeps the engine’s health in better condition as compared to air-cooled engines.