Photovoltaicdevices
Part 1-2: Measurement of current-voltage characteristicsof bifacial photovoltaic(PV) devices
Nationalforeword
This Published Document is the UK implementation of IEC TS 60904-1-2:2019.
The UK participation in its preparation was entrusted to TechnicalCommittee GEL/82 Photovoltaic Energy Systems.
A list of organizations represented on this mittee can be obtained onrequest to its secretary.
of a contract. Users are responsible for its correct application. This publication does not purport to include all the necessary provisions
The British Standards Institution 2019Published by BSI Standards Limited 2019
ISBN 978 0 580 97320 8
ICS 27.160
Compliance with a British Standard cannot confer immunity fromlegal obligations.
This Published Document was published under the authority of the r o a s e d sr
Amendments/corrigenda issued since publication
Date
Text affected
TECHNICAL SPECIFICATION
INTERNATIONALELECTROTECHNICALCOMMISSION
Edition 1.02019-01
ISBN 978-2-8322-6409-6
CONTENTS
FOREWORD. 41 Normative references Scope. ..62 Terms and definitions ..63 3.1 Bifacial PV device. ..73.2 Bifaciality. ..73.3 General considerations. Rear irradiance driven power gain yield .74 5 Apparatus. ..85.1 General. ..85.2 Solar simulator with adjustable irradiance levels for single-side illumination..5.3 5.4 Natural sunlight. Solar simulator with adjustable irradiance levels for double-side illumination ..85.5 Non-irradiated background and background pensation ..86 Additional /-V characterisations for bifacial devices ..96.1 6.2 Determination of bifacialities .. General. ...10 .96.3 Determination of the rear irradiance driven power gain yield. ..116.3.1 6.3.2 General Outdoor rear irradiance driven power gain yield measurement. ..1 .126.3.3 Indoor rear irradiance driven power gain yield measurement with single-6.3.4 Indoor rear irradiance driven power gain yield measurement with side illumination.. .13double-side illumination . .14J-V characterisation of bifacial PV devices in practice. ..157.2 7.1 J-V measurement of reference bifacial PV devices General. 15 157.3 I-V measurement of bifacial PV devices using a reference bifacial device. 16Report. .17
Figure 1 - Scheme of a bifacial PV module and the required non-irradiatedbackground and aperture ..Figure 2 - Front- and rear-side characterization for bifaciality. .10Figure 4-Examples of Pmax as a function of iradiance level on therear side G(for Figure 3 - Outdoor measurement. .12outdoor or double-side illumination) or its 1-side equivalent irradiance G for a deviceFigure 5 - Transmittances of the device (TpuT) and its encapsulant (TENC). of bifaciality p = 80 % .. .14Figure 6 - Example of Pmax.BiFi1o and PmaxBiFi2oo derived from the measurement of Pmax 15at STC conditions Pmax stc and the BiFi coefficient of the reference used in formulae (8) and (9) .... .17
(double-side with G = 1 0oo) or alternatively equivalent front irradiances Ge and the Table 1 - Maximum peak power Pmsx measured at different rear irradiances G rear irradiance driven power gain yield BiFi derived from the slope of the linear fit on Pmax(G.). Also calculated values Pmax BiFioo and Pmax BiFizoo.-..Table 2 -Example of Pmax.BiFitoo and Pmax.BiFi2oo derived from the measurement at STC ..14conditions (G = 0 and G = 1 ooo) and the rear irradiance driven power gain obtainedfrom the bifacial reference device BiFi ref. 17
