The operating mode of a diesel generator is based on the combination of a thermal engine with an electrical generator (also called alternator) to generate electric energy.

Thermal engines run with various kind of fuels. The most frequently used are gasoline, natural gas, LPG, biofuel and for the most powerful ones heavy fuel oil.

At the current state of technology, the highest global efficiency is of 42%, the rest being thermal losses. Higher efficiency rates may be reached with cogeneration : about 90%. Cogeneration produces simultaneously electricity and useful heat.

The operating mode of diesel generator with HT/BT cooling circuit is shown below :

  • n Air circuit
  • n Cylinder water circuit
  • n Cooler water circuit

The turbo-compressor (I) sucks the air flow at (A). The compressed air flows through the charge air cooler (B) before getting into admission collector of the motor (C). The water of the air cooler is kept flowing with the pump (D – not included in our package). The cooling water of the cylinders, the cylinder heads and the oil (H) is kept flowing by the pump installed on the motor. To avoid  ice, there is some glycol in the water. The percentage depends on the winter temperatures of the area.
The water of both circuits goes through a dry cooler with two exchangers (E) and (G). It is cooled down by the air blown by the motorfans that goes first through the cooling circuit of the inlet air.
The circuit (E) called low temperature (BT), intercooler or aftercooler allows to cool down the turbo-compressor inlet air. The cooling down of the inlet air allows to increase air density and therefore the global efficiency of the diesel generator but also to reduce air pollution.
The circuit (G) called high temperature circuit (HT) or jacket water allows to cool the cylinders, cylinder heads and the motoroil.
Using a dry cooler with two exchangers is a good solution in terms of footprint as well as price.
Heatcraft Tempco offers to its customers solutions including dry cooler, electrical box for protection and regulation, expansion chambers
The high temperatures found in the HT circuit HT (95 to 100°C water inlet- Air output, coil up to +80°C) as well as higher ambient temperatures (35°C or even 50°C) require tailor made technical solutions.
With our range of standard T FIN TCFC-ECA dry coolers, we offer a good solution. On demand and if the temperature of the air coming out of the coils is high, we can add special motor fans for extreme temperature.
For ambient temperatures around 45 / 50°C, it is necessary to use a special feature available on our range T FIN TCFC-ECA. This implies to install the motorfans below the coil of the dry cooler and blow the air on the coil. In this case the maximal temperature to which the dry cooler is exposed is the temperature of the ambient air.
In some configuration, the dry cooler is placed in the same location as the diesel generator, which might be a container. Our range of Indoor Fluid Coolers with Available Pressure (AIP) answers perfectly these needs. The dual exchangers fluid cooler is extremely compact, easy to install and equipped with pressure motorfans. The available pressure is defined according to the air side pressure drop of soundtraps and air-ducts of the customer.