ANNEX U.K. METHODOLOGY TO DETERMINE THE CO₂ SAVINGS OF EFFICIENT 12 V MOTOR-GENERATORS FOR CONVENTIONAL COMBUSTION ENGINE POWERED M1 VEHICLES

6. Statistical significance U.K.

It has to be demonstrated for each type, variant and version of a vehicle fitted with the efficient 12 V motor generator that the error in the CO₂ savings calculated in accordance with Formula 9 is not greater than the difference between the total CO₂ savings and the minimum savings threshold specified in Article 9(1) of Implementing Regulation (EU) No 725/2011 (see Formula 10).

Formula 10 U.K.

Where:

MT

:

minimum threshold [g CO₂/km]

:

total CO₂ saving [g CO₂/km]

:

standard deviation of the total CO₂ saving [gCO₂/km]

:

CO₂ correction coefficient due to the positive mass difference between the efficient 12 V motor generator and the baseline alternator. For the data in Table 4 is to be used.

Table 4

CO₂ correction coefficient due to the extra mass

Type of fuel	CO2 correction coefficient due to the positive mass difference ( )[g CO2/km]
Petrol	0,0277 · Δm
Diesel	0,0383 · Δm

Δm (in Table 4) is the extra mass due to the installation of the motor generator. It is the positive difference between the mass of the efficient 12 V motor generator and the mass of baseline alternator. The mass of the baseline alternator is 7 kg. The extra mass is to be verified and confirmed in the verification report to be submitted to the type approval authority together with the application for certifications.