India: Generator Sets
- Regulatory Background
- Emission Standards—Engines up to 800 kW
- Emission Standards—Engines above 800 kW
Regulatory Background
Emissions from new diesel, gas, and petrol engines used in generator sets have been regulated by the Ministry of Environment and Forests, Government of India. The regulations impose type approval testing, production conformity testing and labeling requirements. The regulations also include a list of authorized agencies for type approval testing.
Emission regulations for new engines used in genset applications have been developed and/or strengthened in several steps:
- In 2002, emission standards were adopted for diesel engines above 800 kW. The standards were phased-in between 2003 and 2005 [3004].
- Emission limits for diesel engines ≤ 800 kW were set in 2004 [3002] and strengthened in 2013 [3001].
- In 2016, the emission standards for diesel engines ≤ 800 kW were extended to gas engines and dual fuel engines [5416]. The regulation also introduced emission standards for positive ignition (PI) portable generator set engines ≤ 19 kW.
- A draft notification issued in 2022 [5417] recasts the emission standards for diesel, gas, and petrol engines into one regulation and introduces other changes.
Emission Standards—Engines up to 800 kW
Diesel Engines: 2004 & 2014 standards
Emission standards for new diesel (compression ignition, CI) engines ≤ 800 kW used in genset applications that became applicable in 2004/2005 are listed in Table 1 [3002]. These limits were strengthened effective from April 2014 [3001], Table 2.
| Engine Power (P) | Date | CO | HC | NOx | PM | Smoke |
|---|---|---|---|---|---|---|
| g/kWh | 1/m | |||||
| P ≤ 19 kW | 2004.01 | 5.0 | 1.3 | 9.2 | 0.6 | 0.7 |
| 2005.07 | 3.5 | 1.3 | 9.2 | 0.3 | 0.7 | |
| 19 kW < P ≤ 50 kW | 2004.01 | 5.0 | 1.3 | 9.2 | 0.5 | 0.7 |
| 2004.07 | 3.5 | 1.3 | 9.2 | 0.3 | 0.7 | |
| 50 kW < P ≤ 176 kW | 2004.01 | 3.5 | 1.3 | 9.2 | 0.3 | 0.7 |
| 176 kW < P ≤ 800 kW | 2004.11 | 3.5 | 1.3 | 9.2 | 0.3 | 0.7 |
| Engine Power (P) | Date | CO | NOx+HC | PM | Smoke |
|---|---|---|---|---|---|
| g/kWh | 1/m | ||||
| P ≤ 19 kW | 2014.04 | 3.5 | 7.5 | 0.3 | 0.7 |
| 19 kW < P ≤ 75 kW | 2014.04 | 3.5 | 4.7 | 0.3 | 0.7 |
| 75 kW < P ≤ 800 kW | 2014.04 | 3.5 | 4.0 | 0.2 | 0.7 |
Engines are tested over the 5-mode ISO 8178 D2 test cycle. Smoke opacity must not exceed the limits at full load (Table 1) or at any load point of the test cycle (Table 2). The same limits are applicable for type approval and for conformity of production (COP) testing.
The regulations also set noise limits for diesel generator sets up to 1000 kVA of 75 dB(A) at 1 m, effective 2003.07 [3003].
Gas and Petrol Engines: 2016 standards
The diesel emission standards in Table 2 have been extended to also cover new gas engines in generator set applications [5416], as follows:
- Dedicated natural gas (NG) or liquefied petroleum gas (LPG) engines must meet NOx+HC and CO standards shown in Table 2, effective 2016.07. For these engines, NOx+HC is defined as NOx+NMHC or NOx+RHC. NMHC is equal to 0.3×THC in case of NG, and RHC is equal to 0.5×THC in case of LPG.
- Dual-fuel diesel-NG and diesel-LPG engines must meet NOx+HC, CO, PM, and smoke limits shown in Table 2, effective 2016.07. For these engines, NOx+HC is defined as NOx+THC when running on diesel alone, NOx+NMHC in diesel-NG mode, or NOx+RHC in diesel-LPG mode. NMHC is equal to 0.3×THC in case of NG, and RHC is equal to 0.5×THC in case of LPG.
- A noise limit of 75 dB(A) at 1 meter is applicable to gas and dual-fuel diesel-gas engines from 2017.01
The same regulation [5416] introduces emission standards for dual-fuel petrol and NG or petrol and LPG spark ignited (SI) genset engines up to 19 kW and up to 400 cc displacement, Table 3. Dual-fuel engines are defined as engines that can run on a mixture of petrol and gas fuels, or on petrol alone. The standards are effective 2016.08.
| Class | Displacement D, cc | CO, g/kWh | NOx+HC*, g/kWh |
|---|---|---|---|
| 1 | D ≤ 99 | 250 | 12 |
| 2 | 99 < D ≤ 225 | 250 | 10 |
| 3 | 225 < D ≤ 400 | 250 | 8 |
| * THC is measured in petrol mode of operation. NMHC or RHC is measured in petrol-NG or petrol-LPG dual-fuel mode of operation, respectively. NMHC = 0.3×THC for NG, and RHC = 0.5×THC for LPG. | |||
SI genset engines up to 19 kW must meet a noise limit of 86 dB(A) effective 2016.09.
Diesel, Gas and Petrol Engines: Proposed 2023 standards
Under a draft notification issued in 2022 [5417], emission standards for all generator set engines up to 800 kW, regardless of fuel type, would be be covered by one regulation. The proposal also strengthens several of the emission limits, and introduces emission standards for positive ignition (PI) engines above 400 cc.
The proposed emissions limits for CI engines and for PI engines above 800 cc are listed in Table 4. The emission limits for air-cooled PI engines up to 19 kW used in portable generator sets are shown in Table 2. All standards would be effective from 2023.07.
| Power, P, kW | NOx | HC* | NOx+HC* | CO | PM† | Smoke† |
|---|---|---|---|---|---|---|
| g/kWh | 1/m | |||||
| P ≤ 8 | - | - | 7.5 | 3.5 | 0.30 | 0.7 |
| 8 < P ≤ 19 | - | - | 4.7 | 3.5 | 0.30 | 0.7 |
| 19 < P ≤ 56 | - | - | 4.7 | 3.5 | 0.03 | 0.7 |
| 56 < P ≤ 560 | 0.40 | 0.19 | - | 3.5 | 0.02 | 0.7 |
| 560 < P ≤ 800 | 0.67 | 0.19 | - | 3.5 | 0.03 | 0.7 |
|
* THC is measured in diesel and petrol mode of operation. NMHC or RHC is measured when operated with gaseous fuels. † Applicable to CI engines only. | ||||||
| Class | Displacement D, cc | CO, g/kWh | NOx+HC*, g/kWh |
|---|---|---|---|
| 1 | D ≤ 99 | 250 | 10 |
| 2 | 99 < D ≤ 225 | 250 | 8 |
| 3 | 225 < D ≤ 800 | 250 | 6 |
| * THC is measured in petrol mode of operation. NMHC or RHC is measured when operated with NG or LPG, respectively. | |||
All CI engines and PI engines above 800 cc are tested on an engine dynamometer. Portable generator sets (up to 19 kW and up to 800 cc engine displacement) are tested using a resistive load bank.
The following emission durability periods are applicable to PI and CI engines above 19 kW:
- Constant speed engines 19-56 kW: 3000 hours
- Variable speed engines 19-56 kW: 5000 hours
- All engines above 56 kW: 8000 hours
As an alternative to service accumulation, manufacturers may use the following deterioration factors: CO = 1.3; HC = 1.3; NOx = 1.15; PM (CI only) = 1.05.
Emission Standards—Engines above 800 kW
Emission standards for new diesel engines above 800 kW used in genset applications were phased-in between 2003 and 2005, Table 6 [3004].
| Date | CO | NMHC | NOx | PM |
|---|---|---|---|---|
| mg/Nm3 | mg C/Nm3 | ppm(v) | mg/Nm3 | |
| Until 2003.06 | 150 | 150 | 1100 | 75b |
| 2003.07 - 2005.06 | 150 | 100 | 970 (710a) | 75c |
| 2005.07 | 150 | 100 | 710 (360a) | 75c |
|
a For engines in plants of total power rating above 75/150 MW located in urban/rural areas, respectively. b 150 mg/Nm3 for engines fueled with furnace oil. c 100 mg/Nm3 for engines fueled with furnace oil. | ||||
Concentrations are corrected to dry exhaust conditions at 15% residual O2.