CPCB 2 NORMS FOR DIESEL GENERATORS. What does it mean and what are its implications?

The Central Pollution Control Board, under the Ministry of Environment and Forest, has announced the new CPCB 2 norms that will mandate manufacturers of the power generators to make all their engines up to 800 kW, CPCB 2 compliant. While “environmentally friendly engines” are naturally implied by these norms, here is a low down on what it really means.


In a bid to improve the quality of air, the Board has laid down more stringent norms, the CPCB 2, that will make compliant engines have a lower rate of Nitrogen Oxide, Hydrogen Carbon and Particulate matters emissions.


Below is the snapshot of the emission limits of the various permissible emission limits for given ratings:



In order to make its engines CPCB 2 ready, Mahindra Powerol uses two techniques. One is a time modification to when the fuel makes its way inside an engine's controlled-explosion room, better known as a combustion chamber. The perfect timing will allow the fuel to burn more evenly and thoroughly. The other technique will include an addition of an EGR system. In this the exhaust gases will be ‘reconstituted’ back into the engines so that the overall carbon emissions of the CPCB 2 compliant engines will be much lower with the same fuel consumption per hour producing equal amounts of energy than the CPCB 1 compliant engines.


Mahindra Powerol has begun production of its CPCB 2 compliant diesel engines and generators.


Exhaust Gas Reconstituted System (EGR system)
The Exhaust System typically removes the exhaust gases from the Engine into the atmosphere. The new EGR system will send measured quantity of exhaust gas into the engine cylinder under various engine operating conditions. This is achieved by opening the EGR valve to a pre-determined level and allowing the exhaust gases to pass through the engine. Some models may also incorporate an Exhaust Cooling Unit.

Exhaust gas is made to pass through EGR cooler which is cooled by Engine water of the cooling system to reduce the gas temperature. After passing through the EGR cooler, exhaust gas enters the intake system of the engine.


EGR system components
EGR cooler: The Mahindra Powerol CPCB 2 compliant diesel generator also comes with an EGR cooler which is required to cool the exhaust gas to get the additional benefit of NOx reduction.

EGR valve: It is a solenoid operated valve for EGR supply. EGR valve closes or opens according to the ECU input provided by the Dual Temperature Switch and Speed fluctuations.

Mahindra Powerol’s new CPCB 2 engines and diesel generators are guaranteed to bring about a positive environmental impact. It has already produced over 150 engines that are running for several hours in the field.