Diesel Engine Power Plant

Diesel engine power plants are more efficient than the other types of engine plant for the same capacity. The diesel engine plants are more suitable for low- and medium-power outputs. These plants are commonly employed where fuel prices are low and water availability is limited. The capacity of the diesel power plants is about 5 MW; such plants are used as standby plants to hydro- and diesel power plants for small output. These plants do not require large amount of water for cooling. Diesel engines are widely used in railroad locomotives, road buildings, ship propulsion electric generators for feeding supply to public industrial and institutional purpose, etc. A wide application of diesel engine is mainly due to the less cost fuel than gasoline products.

Diesel engine power plant has the following systems by means of which electric power can be generated. Schematic diagram of diesel engine power plant.

(i) Air intake and exhaust system: This system consists of pipes arrangement for admitting fresh atmospheric air into the diesel engine, and also to pump out the exhaust gases to the atmosphere. Filters are needed at the air inlet to remove dust particles etc. from the incoming air. At the outlet of the system silencer is provided to reduce the noise when the exhaust gases are coming out from the engine.

In order to reduce the specific fuel consumption and to increase the engine capacity, the intake system must have to maintain minimum pressure loss.

(ii) Fuel supply system: This system consists of fuel tank to store fuel, and fuel pumps and filters to transfer and inject fuel into the diesel engine. Fuel oil is supplied by trucks, rail, cars, etc. at the plant site.

(iii) Cooling system: This system circulates sufficient amount of water around the engine in order to maintain desired temperature. The hot water re cooled in the cooling ponds again re circulated into the system.

(iv) Lubricating system: This system is necessary to reduce ware on the rubbing parts and friction. It consists of lubricating oil tank, pumps, filters, etc.

(v) Starting system: Starting system is essential for the initial starting of engine. It consists of compressor, battery, and electric motor (or) self-starter.

Diesel engine is nothing but internal combustion engine, in which fuel is ignited by injecting into system thereby compression. So that these engines are also called as compression ignition engines. This engine will convert heat energy into mechanical work. In the combustion chamber, fuel burns rapidly and gases attain very high temperature and produces extremely hot compressed gases. These gases expand and push back the piston of engine. This is nothing but the power stroke in which mechanical work is done. This work is helpful to rotate the crank shaft on which generator is mounted, which converts mechanical power into electric power.