Annex II Energy efficiency classes and calculation method
United Kingdom
The energy efficiency class of light sources shall be determined as set out in Table 1, on the basis of the total mains efficacy ηTM, which is calculated by dividing the declared useful luminous flux Φuse (expressed in lm) by the declared on-mode power consumption Pon (expressed in W) and multiplying by the applicable factor FTM of Table 2, as follows:
ηTM = (Φuse/Pon) × FTM (lm/W).
Table 1
Energy efficiency classes of light sources
| Energy efficiency class | Total mains efficacy ηΤM (lm/W) |
|---|---|
| A | 210 ≤ ηΤM |
| B | 185 ≤ ηΤM < 210 |
| C | 160 ≤ ηΤM < 185 |
| D | 135 ≤ ηΤM < 160 |
| E | 110 ≤ ηΤM < 135 |
| F | 85 ≤ ηΤM < 110 |
| G | ηΤM < 85 |
Table 2
Factors FTM by light source type
| Light source type | Factor FTM |
|---|---|
| Non-directional (NDLS) operating on mains (MLS) | 1,0 |
| Non-directional (NDLS) not operating on mains (NMLS) | 0,926 |
| Directional (DLS) operating on mains (MLS) | 1,176 |
| Directional (DLS) not operating on mains (NMLS) | 1,089 |