Appendix B. Calculation of BER and TER
This appendix sets out the calculation of the emission rates BER and TER used in the Part L2 (2006) Criterion 1 compliance test.
The CO2 variables used in the calculation can be viewed in Vista:
Cse = total System elec. CE
Cst = total Total system CE
Clt = total Total lights CE (assumed to be electrical)
Note that carbon emissions associated with Equipment energy consumption are not taken into account in the BER and TER calculations.
BER calculation
Electrical carbon emissions (Cse and Clt) are subject to adjustment factor Fe as follows (see L2A Table 3):
If power factor < 0.9, Fe = 1.0.
If 0.9 < power factor < 0.95, Fe = 1 - 0.01 = 0.99.
If power factor > 0.95, Fe = 1 - 0.025 = 0.975.
Lighting energy consumption is adjusted with factor F1 as follows:
If there is metering and warning of out-of-range values, Fl = 0.95, otherwise Fl=1.0.
Applying these factors the revised carbon emission figure to be carried forward to the BER calculation is
BER = Cst - (1-Fe)´Cse + Fe´Fl´Clt
TER calculation
Notional building carbon emissions rate,
NER = Cst + Clt
TER = NER * (1.0 – Improvement Factor) ´ (1.0 – LZC Factor)
where (L2A Table 1):
Improvement Factor is a function of system type weighted by floor area
LZC Factor = 0.1
