ANNEX U.K. METHODOLOGY TO DETERMINE THE CO₂ SAVINGS OF EXTERIOR VEHICLE LIGHTING USING LIGHT EMITTING DIODES (LED).

1. INTRODUCTION U.K.

In order to determine the CO₂ emission reductions that can be attributed to a package of efficient exterior LED lights consisting of an appropriate combination of vehicle lights referred to in Article 2 for the use in an M₁ vehicle, it is necessary to establish the following:

(1)

testing conditions;

(2)

test equipment;

(3)

determination of the power savings;

(4)

calculation of the CO₂ savings;

(5)

calculation of the statistical error.

2. SYMBOLS, PARAMETERS AND UNITS U.K.

Latin symbols U.K.

—

CO₂ savings [g CO₂/km]

CO₂

—

Carbon dioxide

[F1 CF

—

Conversion factor as defined in Table 3]

m

—

Number of efficient exterior LED lights composing the package

n

—

Number of measurements of the sample

P

—

Power consumption of the vehicle light [W]

—

Standard deviation of the LED light power consumption [W]

—

Standard deviation of the LED light power consumption mean [W]

—

Standard deviation of the total CO₂ savings [g CO₂/km]

UF

—

Usage factor [-] as defined in Table 4

v

—

Mean driving speed of the New European Driving Cycle (NEDC) [km/h]

[F1 V _Pe

—

Consumption of effective power as defined in Table 2]

—

Sensitivity of calculated CO₂ savings related to the LED light power consumption

Textual Amendments

F1 Substituted by Commission Implementing Decision (EU) 2020/1168 of 6 August 2020 amending Implementing Decision (EU) 2016/587 as regards efficient vehicle exterior lighting using light emitting diodes in passenger cars capable of running on certain alternative fuels (Text with EEA relevance).

Greek symbols U.K.

Δ

—

Difference

η_A

—

Alternator efficiency [%]

Subscripts U.K.

Index (i) refers to vehicle lights

Index (j) refers to measurement of the sample

EI

—

Eco-innovative

RW

—

Real-world conditions

TA

—

Type approval conditions

B

—

Baseline

3. TESTING CONDITIONS U.K.

The testing conditions shall fulfil the requirements of Regulation UN/ECE No 112(1) on Uniform provisions concerning the approval of motor vehicle headlamps emitting an asymmetrical passing beam or a driving beam or both and equipped with filament lamps and/or light-emitting diode (LED) modules. The power consumption shall be determined in accordance with point 6.1.4 of Regulation UN/ECE No 112 and points 3.2.1 and 3.2.2 of Annex 10 to that Regulation.

4. TEST EQUIPMENT U.K.

The following equipment is to be used, as shown in the figure:

• a power supply unit (i.e. variable voltage supplier);

• two digital multimeters, one for measuring the DC-current, and the other for measuring the DC-voltage. In the figure, a possible test set-up is shown, when the DC-voltage meter is integrated in the power supply unit.

5. MEASUREMENTS AND DETERMINATION OF THE POWER SAVINGS U.K.

For each efficient exterior LED light included in the package the measurement of the current shall be performed as shown in the figure at a voltage of 13,2 V. LED module(s) operated by an electronic light source control gear, shall be measured as specified by the applicant.

The manufacturer may request that other measurements of the current shall be done at other additional voltages. In that case, the manufacturer must hand over verified documentation on the necessity to perform these other measurements to the [F2 Secretary of State]. The measurements of the currents at each of those additional voltages are to be performed consecutively at least five (5) times. The exact installed voltages and the measured current is to be recorded in four decimals.

Textual Amendments

F2 Words in Annex substituted (31.12.2020) by The Road Vehicle Carbon Dioxide Emission Performance Standards (Cars and Vans) (Amendment) (EU Exit) Regulations 2019 (S.I. 2019/550), regs. 1, 22(3) (as inserted by S.I. 2020/1418, regs. 1(2), 2(6)(b)); 2020 c. 1, Sch. 5 para. 1(1)

The power consumption has to be determined by multiplying the installed voltage with the measured current. The average of the power consumption for each efficient exterior LED light () has to be calculated. Each value must be expressed in 4 decimals. When a stepper motor or electronic controller is used for the supply of the electricity to the LED lamps, then the electric load of this component part is to be excluded from the measurement.

The resulting power savings of each efficient exterior LED light (ΔP_i) are to be calculated with the following formula:

Formula 1 U.K.

where the power consumption of the corresponding baseline vehicle light is defined by Table 1.

Table 1

Power requirements for different baseline vehicle lights

Vehicle light	Total electric power (PB)[W]
Low beam headlamp	137
High beam headlamp	150
Front position	12
License plate	12
Front fog lamp	124
Rear fog lamp	26
Front turn signal lamp	13
Rear turn signal lamp	13
Reversing lamp	52

6. CALCULATION OF THE CO₂ SAVINGS U.K.

The total CO₂ savings of the lighting package are to be calculated by Formula 2.

Formula 2 U.K.

where

v

:

Mean driving speed of the NEDC [km/h], which is 33,58 km/h

η_A

:

Alternator efficiency [%], which is 67 %

[F1 V _Pe

:

Consumption of effective power as defined in Table 2

Table 2

Consumption of effective power

Type of Engine	Consumption of effective power (V pe ) [l/kWh]
Petrol/E85	0,264
Petrol/E85 Turbo	0,280
Diesel	0,220
LPG	0,342
LPG Turbo	0,363
	Consumption of effective power (V pe ) [m 3 /kWh]
CNG (G20)	0,259
CNG (G20) Turbo	0,275

CF

:

Conversion factor as defined in Table 3

Table 3

Fuel conversion factor (CF)

Type of fuel	Conversion factor (CF) [gCO 2 /l]
Petrol/E85	2 330
Diesel	2 640
LPG	1 629
	Conversion factor (CF) [gCO 2 /m 3 ]
CNG (G20)	1 795]

UF

:

Usage factor of the vehicle light [-] as defined in Table 4

Table 4

Usage factor for different vehicle lights

Vehicle light	Usage factor (UF)[-]
Low beam headlamp	0,33
High beam headlamp	0,03
Front position	0,36
License plate	0,36
Front fog lamp	0,01
Rear fog lamp	0,01
Front turn signal lamp	0,15
Rear turn signal lamp	0,15
Reversing lamp	0,01

7. CALCULATION OF THE STATISTICAL ERROR U.K.

The statistical errors in the outcomes of the testing methodology caused by the measurements are to be quantified. For each efficient exterior LED light included in the package the standard deviation is calculated as defined by Formula 3.

Formula 3 U.K.

where:

n

:

Number of measurements of the sample, which is at least 5

The standard deviation of the power consumption of each efficient exterior LED light () leads to an error in the CO₂ savings (). This error is to be calculated by means of Formula 4

Formula 4 U.K.

8. STATISTICAL SIGNIFICANCE U.K.

It has to be demonstrated for each type, variant and version of a vehicle fitted with the combination of the efficient exterior LED lights that the error in the CO₂ savings calculated with Formula 4 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 5).

Formula 5 U.K.

where:

MT

:

Minimum threshold [gCO₂/km], which is 1 gCO₂/km

Where the total CO₂ emission savings of the of the package of the efficient exterior LED lights, as a result of the calculation using Formula 5, are below the threshold specified in Article 9(1) of Implementing Regulation (EU) No 725/2011, the second subparagraph of Article 11(2) of that Regulation shall apply.

(1)

E/ECE/324/Rev.2/Add.111/Rev.3 — E/ECE/TRANS/505/Rev.2/Add.111/Rev.3, 9 January 2013