IEC 61853-3:2018

IEC 61853-3 ®
Edition 1.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Photovoltaic (PV) module performance testing and energy rating –
Part 3: Energy rating of PV modules

Essais de performance et caractéristiques assignées d'énergie des modules
photovoltaïques (PV) –
Partie 3: Caractéristiques assignées d’énergie des modules PV

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IEC 61853-3 ®
Edition 1.0 2018-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Photovoltaic (PV) module performance testing and energy rating –

Part 3: Energy rating of PV modules

Essais de performance et caractéristiques assignées d'énergie des modules

photovoltaïques (PV) –
Partie 3: Caractéristiques assignées d’énergie des modules PV

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 27.160 ISBN 978-2-8322-5989-4

– 2 – IEC 61853-3:2018 © IEC 2018
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 Testing . 7
5 Report . 7
6 Module energy collection . 8
6.1 General . 8
6.2 Input module data for energy rating . 8
6.3 Input standard reference climatic profiles . 9
7 Procedure for energy rating . 9
7.1 General . 9
7.2 In-plane global irradiance corrected for angular incidence effects . 10
7.3 Spectrally corrected global in-plane irradiance . 11
7.4 Calculation of module temperature . 12
7.5 Determination of instantaneous module power . 12
7.6 Calculation of hourly module energy output . 13
7.7 Calculation of annual module energy output . 13
7.8 Climatic specific energy rating . 13

Figure 1 – Flow chart of calculation procedure . 10

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PHOTOVOLTAIC (PV) MODULE PERFORMANCE
TESTING AND ENERGY RATING –
Part 3: Energy rating of PV modules

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61853-3 has been prepared by IEC technical committee 82: Solar
photovoltaic energy systems.
The text of this International Standard is based on the following documents:
FDIS Report on voting
82/1441/FDIS 82/1451/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 4 – IEC 61853-3:2018 © IEC 2018
A list of all parts in the IEC 61853, published under the general title Photovoltaic (PV) module
performance testing and energy rating, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
INTRODUCTION
This International Standard series establishes IEC requirements for determining PV module
performance in terms of power (watts), specific module energy rating (kWh/kW) and climatic
specific energy rating (dimensionless). It is written to be applicable to all PV technologies
including non-linear devices. The methodology does not take into account either progressive
degradation or transient behaviour such as light induced changes and/or thermal annealing.
This series consists of four parts:
• IEC 61853-1: Photovoltaic (PV) module performance testing and energy rating – Part 1:
Irradiance and temperature performance measurements and power rating, which describes
requirements for evaluating PV module performance in terms of power (watts) rating over
a range of irradiances and temperatures;
• IEC 61853-2: Photovoltaic (PV) module performance testing and energy rating – Part 2:
Spectral responsivity, incidence angle, and module operating temperature measurements,
which describes test procedures for measuring the effect of varying angles of incidence
and sunlight spectra as well as the estimation of module temperature from irradiance,
ambient temperature, and wind speed;
• IEC 61853-3: Photovoltaic (PV) module performance testing and energy rating – Part 3:
Energy rating of PV modules, which describes the calculations for PV module ratings; and
• IEC 61853-4: Photovoltaic (PV) module performance testing and energy rating – Part 4:
Standard reference climatic profiles, which describes the standard time periods and
environmental data set that shall be used for the energy rating calculations.

– 6 – IEC 61853-3:2018 © IEC 2018
PHOTOVOLTAIC (PV) MODULE PERFORMANCE
TESTING AND ENERGY RATING –
Part 3: Energy rating of PV modules

1 Scope
This part of IEC 61853 describes the calculation of PV module energy rating values.
IEC 61853-1 describes requirements for evaluating PV module performance at various
temperatures and irradiances in terms of power (watts) rating. IEC 61853-2 describes test
procedures for determining module temperature from irradiance, ambient temperature and
wind speed, a method for measuring angle of incidence effects, and spectral responsivity.
IEC 61853-4 describes the standard reference climatic profiles (standard environmental data
sets) that are used for calculating energy rating values.
The purpose of this document is to define a methodology to determine the PV module energy
output (watt-hours), and the climatic specific energy rating (dimensionless) for a complete
year at maximum power operation for the reference climatic profile(s) given in IEC 61853-4. It
is applied to determine a specific module output in a standard reference climatic profile for the
purposes of comparison of rated modules.
The methodology does not take into account either progressive degradation or transient
behaviour such as light induced changes and/or thermal annealing.
The present document applies to mono-facial modules.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 60891, Photovoltaic devices – Procedures for temperature and irradiance corrections to
measured I-V characteristics
IEC 60904-3, Photovoltaic devices – Part 3: Measurement principles for terrestrial
photovoltaic (PV) solar devices with reference spectral irradiance data
IEC 60904-7, Photovoltaic devices – Part 7: Computation of the spectral mismatch correction
for measurements of photovoltaic devices
IEC 60904-8, Photovoltaic devices – Part 8: Measurement of spectral responsivity of a
photovoltaic (PV) device
IEC 60904-8-1, Photovoltaic devices – Part 8-1: Measurement of spectral responsivity of
multi-junction photovoltaic (PV) devices
IEC TS 61836, Solar photovoltaic energy systems – Terms, definitions and symbols
IEC 61853-1, Photovoltaic (PV) module performance testing and energy rating – Part 1:
Irradiance and temperature performance measurements and power rating

IEC 61853-2, Photovoltaic (PV) module performance testing and energy rating – Part 2:
Spectral responsivity, incidence angle and module operating temperature measurements
IEC 61853-4, Photovoltaic (PV) module performance testing and energy rating – Part 4:
Standard reference climatic profiles
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC TS 61836 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
climatic specific energy rating
CSER
normalised energy collection for the reference climatic profile, i.e. the ratio of the actual
energy collection to that which would have been obtained if the PV module always performed
with the energy conversion efficiency measured under standard test conditions
Note 1 to entry: CSER is dimensionless.
4 Testing
No testing is performed within this document; however, the energy rating calculations defined
in Clause 7 use data from measurements made according to IEC 61853-1 and IEC 61853-2
and the standard reference climatic profiles from IEC 61853-4.
5 Report
Following completion of the procedure, a report with the resulting energy ratings shall be
prepared by the test agency. Each certificate or test report shall include at least the following
information.
a) a title;
b) name and address of the test laboratory and location where the calibration or tests were
carried out;
c) unique identification of the report and of each page;
d) name and address of client, where appropriate;
e) description and identification of the item calibrated or tested;
f) characterization and condition of the calibration or test item;
g) date of receipt of test item and date(s) of calibration or test, where appropriate;
h) identification of calibration or test method used;
i) reference to sampling procedure, where relevant;
j) any deviations from, additions to or exclusions from the calibration or test method, and
any other information relevant to a specific calibration or test, such as environmental
conditions;
k) the filenames of the reference climate data files and the version of IEC 61853-4
corresponding to the data files;

– 8 – IEC 61853-3:2018 © IEC 2018
l) a specification of the interpolation routines used to derive the module data from the
measured performance tables;
m) module energy output for the individual test devices, as well as the averaged data (for the
three modules submitted for testing in IEC 61853-1);
n) climatic specific energy rating for the individual test devices, as well as the averaged data
(for the three modules submitted for testing in IEC 61853-1);
o) a statement of the estimated uncertainty of the energy rating results;
p) a signature and title, or equivalent identification of the person(s) accepting responsibility
for the content of the report, and the date of issue;
q) where relevant, a statement to the effect that the results relate only to the items calibrated
or tested;
r) a statement that the report shall not be reproduced except in full, without the written
approval of the laboratory.
6 Module energy collection
6.1 General
The output power of a PV module depends primarily on the following parameters:
• Irradiance incident on the module
• Module temperature
Module temperature is a derived parameter, and is determined from the tabulated irradiance,
ambient temperature and wind speed, together with module thermal parameters as
determined in IEC 61853-2.
These parameters are a function of the environmental conditions over the defined year long
time period of each standard reference climatic profile, tabulated as an hourly data set in
IEC 61853-4. Angle of incidence and spectral effects are considered in the calculations for
reasons of completeness, and to ensure that modules with special characteristics are rated
correctly.
6.2 Input module data for energy rating
The following module performance parameters influence the instantaneous power output and
hence energy production of a PV module:
a) Matrix of P versus irradiance (at AM 1,5 g) and versus module temperature
max
(IEC 61853-1) which may be interpolated to obtain the instantaneous power at a given
irradiance and module temperature.
b) Thermal coefficients u , u describing module operating temperature as a function of
0 1
irradiance and wind speed, which are used to calculate instantaneous module temperature
(IEC 61853-2).
c) Angle of incidence response a (IEC 61853-2) used to calculate the effective light
r
transmission into the module at different incidence angles.
d) Spectral responsivity (IEC 61853-2), used to calculate spectral mismatch and hence
correct to reference spectral conditions. It is provided as a table of values for a range of
wavelengths over which the module is responsive.
The performance parameters listed in a) are measured by procedures given in IEC 61853-1.
The performance parameters listed in items b), c) and d) are determined according to
procedures given in IEC 61853-2. In accordance with procedures in IEC 61853-2, in some
cases the parameters in points b), c) may be nominal values provided therein.

6.3 Input standard reference climatic profiles
IEC 61853-4 provides the standard reference climatic profiles to be used for energy rating.
The information provided with each standard reference climatic profile is described in
IEC 61853-4:2018, subclause 4.2.
7 Procedure for energy rating
7.1 General
For each of the three modules and for the average of the values of the three modules reported
from IEC 61853-1 the following procedure shall be followed. The module peak power and
energy output for a particular time step is determined by following a series of calculations
described in this clause. The module energy output is calculated per hour. These individual
hourly energy values are then summed over the data set to determine the annual energy
production.
The procedures for each time step are outlined in Figure 1.

– 10 – IEC 61853-3:2018 © IEC 2018
Select reference climate profile
G, B, D, G(λ), R(λ), T , θ and v in hourly time steps for 1 year and H
amb p
Next time step, j
AOI correction of beam and Formulas (1) and (2), with;
diffuse components: a from IEC 61853-2
r
B and D θ , B and D from IEC 61853-4
corr,j corr,j j j j
AOI corrected irradiance
G Formulas (4) and (5)
corr,AOI,j
G(λ)
corr,AOI,j
Formula (6), with;
Spectral correction factor
R(λ) from IEC 61853-4
j
C
s,j
R(λ) from IEC 61853-2
STC
Spectrally corrected irradiance
Formula (7)
G
corr,j
Formula (8), with;
Module temperature
u , u , from IEC 61853-2
0 1
T
mod,j
T , v from IEC 61853-4
amb, j j
Module power output
P , T and G from IEC 61853-1
max
P
mod,j and IEC 60891
Energy output for time step j
Formula (18)
E = P • 1 hour
mod,j mod,j
No
j = 8 760?
Yes
Module energy yield output (kWh)
Formulas (19) and (20)
Climatic specific energy rating (dimension less)

IEC
Figure 1 – Flow chart of calculation procedure
7.2 In-plane global irradiance corrected for angular incidence effects
The corrected in-plane direct B and diffuse D components for angle of incidence are
corr corr
given by:
cos�𝜃𝜃 �
𝑗𝑗
1−exp (− )
𝑎𝑎
r
𝐵𝐵 =𝐵𝐵 � � (1)
corr,j j 1
1−exp (− )
𝑎𝑎
r
1 4 𝜋𝜋−𝛽𝛽−sin𝛽𝛽 𝜋𝜋−𝛽𝛽−sin𝛽𝛽
( )
𝐷𝐷 =𝐷𝐷�1−𝑒𝑒𝑒𝑒𝑒𝑒�− � �sin𝛽𝛽 + � + 0,5𝑎𝑎 − 0,154 �sin𝛽𝛽 + ���� (2)
corr,j j r
𝑎𝑎 3𝜋𝜋 1+cos𝛽𝛽 1+cos𝛽𝛽
r
where
th
B is the uncorrected in-plane direct irradiance at the j hour,
j
th
D is the uncorrected in-plane diffuse irradiance at the j hour,
j
θ is the angle between sun and the normal to the module surface at hour j,
j
β is the inclination angle (in units of radians) of the module relative to horizontal,
and
factor a is provided by the analysis of the angle-of-incidence measurements, as carried
r
out in IEC 61853-2.
D is not given directly in the data sets but can be calculated from the global in-plane
j
irradiance G and the direct in-plane irradiance B :
j j
𝐷𝐷 =𝐺𝐺 −𝐵𝐵 (3)
𝑗𝑗 𝑗𝑗 𝑗𝑗
Finally, the angular corrected in-plane global irradiance G can be calculated as:
corr,AOI,j
𝐺𝐺 =𝐵𝐵 +𝐷𝐷 (4)
corr,AOI,j corr,j corr,j
The climatic data sets contain the in-plane global and direct broadband irradiance and the
spectrally resolved in-plane global irradiance for a set of discrete bands but not the direct or
diffuse spectrally resolved irradiance. To calculate the angular corrected in-plane spectrally
resolved global irradiance, the following formula shall be applied:
𝐺𝐺 𝐺𝐺(λ)
corr,AOI,j ∙ 𝑗𝑗
𝐺𝐺(λ) = (5)
corr,AOI,j
𝐺𝐺
𝑗𝑗
where
th
𝐺𝐺 is the angular corrected broadband in-plane irradiance for the j hour, and
corr,AOI,j
G(λ) is the in-plane global spectral irradiance in discrete bands at hour j.
j
7.3 Spectrally corrected global in-plane irradiance
Normally the spectral correction is applied to the short-circuit current according to
IEC 60904-7. The change in short-circuit current when applying a different spectrum can be
used to apply a proportional change to the irradiance, obtaining an “effective” or “corrected”
irradiance, G .
corr
The module spectral responsivity S(λ) measured for different wavelengths λ as prescribed in
IEC 61853-2 and IEC 60904-8 is used. The spectral correction factor C at hour j can then be
s
calculated as:
𝜆𝜆
𝑒𝑒
1000∫ 𝑆𝑆(λ)𝑅𝑅 (λ)𝑑𝑑λ
corr,AOI,j
𝜆𝜆
𝑠𝑠
𝐶𝐶 = (6)
s,j 𝜆𝜆
𝑒𝑒
( ) ( )
𝐺𝐺 ∫ 𝑆𝑆λ𝑅𝑅 λ𝑑𝑑λ
corr,AOI,j 𝑆𝑆𝑆𝑆𝑆𝑆
𝜆𝜆
𝑠𝑠
where
G is the AOI-corrected global in-plane irradiance,
corr,AOI,j
R (λ) is the spectrally resolved in-plane irradiance in W/(m ⋅nm) and calculated as
corr,AOI,j
the ratio of the G(λ) and the width of each spectral band, in nm,
corr,AOI,j
R (λ) is the corresponding spectral intensity for the standard test condition
STC
spectrum AM 1,5 g (IEC 60904-3).
The integration limits are: λ = 300 nm, λ = 4 000 nm and the calculation is performed by
s e
numerical integration. The spectrally corrected global in-plane irradiance at the j hour,G ,
corr,j
is calculated as:
𝐺𝐺 =𝐶𝐶 ∙𝐺𝐺 (7)
corr,j s,j corr,AOI,j
– 12 – IEC 61853-3:2018 © IEC 2018
For multi-junction PV modules the spectral correction may only be made when the same
junction is limiting under both the reference and the hourly spectral irradiances (refer to
IEC 60904-8-1).
7.4 Calculation of module temperature
The module temperature T shall be calculated using the following formula:
mod
𝐺𝐺
corr,AOI,j
𝑇𝑇 =𝑇𝑇 + (8)
mod,j amb,j
𝑢𝑢 + 𝑢𝑢 𝑣𝑣
0 1
𝑗𝑗
where
T is the ambient temperature, extracted from IEC 61853-4,
amb
v is the wind speed at the height of the module, extracted from
j
IEC 61853-4, and
G is the in-plane global irradiance, corrected for angle-of-
corr,AOI,j
th
incidence effects, for the j hour,
the two parameters u and u are reported from the procedure described in IEC 61853-2.
0 1
7.5 Determination of instantaneous module power
The calculated parameters from formulas (7) and (8) (G and T ) can now be used to
corr mod
determine the module power P (G ,T ) by using the power table (P ) generated from
mod corr mod max
IEC 61853-1. In general, it is necessary to perform a 2-D bilinear interpolation, or equivalent,
of the P values given in the table at different temperature and irradiance conditions. When
max
the values of G and T are outside the range of values in the power table a linear
corr mod
extrapolation should be used.
To calculate the module power P(G,T) for given values of in-plane irradiance G and module
temperature T by bilinear interpolation the following procedure should be used. Find the
values T and T in the power table such that T < T < T , and similar G and G such that
1 2 1 2 1 2
G < G < G .
1 2
For each of the pairs of (G,T) values calculate the quantity η(G,T) = P(G,T)/G. Then calculate:
𝐺𝐺−𝐺𝐺
( ) ( ) ( ) ( )
𝜂𝜂𝐺𝐺,𝑇𝑇 =𝜂𝜂𝐺𝐺 ,𝑇𝑇 + �𝜂𝜂𝐺𝐺 ,𝑇𝑇 −𝜂𝜂𝐺𝐺 ,𝑇𝑇 � (9)
1 1 1 2 1 1 1
𝐺𝐺 −𝐺𝐺
2 1
𝐺𝐺−𝐺𝐺
𝜂𝜂(𝐺𝐺,𝑇𝑇 ) =𝜂𝜂(𝐺𝐺 ,𝑇𝑇 ) + �𝜂𝜂(𝐺𝐺 ,𝑇𝑇 )−𝜂𝜂(𝐺𝐺 ,𝑇𝑇 )� (10)
2 1 2 2 2 1 2
𝐺𝐺 −𝐺𝐺
2 1
𝑇𝑇−𝑇𝑇 𝑇𝑇−𝑇𝑇
2 1
𝜂𝜂(𝐺𝐺,𝑇𝑇) = 𝜂𝜂(𝐺𝐺,𝑇𝑇 ) + 𝜂𝜂(𝐺𝐺,𝑇𝑇 ) (11)
1 2
𝑇𝑇−𝑇𝑇 𝑇𝑇−𝑇𝑇
2 1 2 1
The interpolated power can then be found as P(G,T) = η(G,T)∙G.
Linear extrapolation when only one of the variables G,T is outside the range of the power
table values can be found in the following way, where T is the highest temperature value in
max
the table:
𝐺𝐺−𝐺𝐺
( ) ( ) ( ) ( )
𝜂𝜂𝐺𝐺,𝑇𝑇 =𝜂𝜂𝐺𝐺 ,𝑇𝑇 + �𝜂𝜂𝐺𝐺 ,𝑇𝑇 −𝜂𝜂𝐺𝐺 ,𝑇𝑇 � (12)
𝑚𝑚𝑎𝑎𝑚𝑚 1 𝑚𝑚𝑎𝑎𝑚𝑚 2 𝑚𝑚𝑎𝑎𝑚𝑚 1 𝑚𝑚𝑎𝑎𝑚𝑚
𝐺𝐺 −𝐺𝐺
2 1
𝐺𝐺−𝐺𝐺
𝜂𝜂(𝐺𝐺,𝑇𝑇 ) =𝜂𝜂(𝐺𝐺 ,𝑇𝑇 ) + �𝜂𝜂(𝐺𝐺 ,𝑇𝑇 )−𝜂𝜂(𝐺𝐺 ,𝑇𝑇 )� (13)
𝑚𝑚𝑎𝑎𝑚𝑚−1 1 𝑚𝑚𝑎𝑎𝑚𝑚−1 2 𝑚𝑚𝑎𝑎𝑚𝑚−1 1 𝑚𝑚𝑎𝑎𝑚𝑚−1
𝐺𝐺 −𝐺𝐺
2 1
𝑇𝑇−𝑇𝑇
𝑚𝑚𝑎𝑎𝑚𝑚−1
𝜂𝜂(𝐺𝐺,𝑇𝑇) =𝜂𝜂(𝐺𝐺,𝑇𝑇 ) + �𝜂𝜂(𝐺𝐺,𝑇𝑇 )−𝜂𝜂(𝐺𝐺,𝑇𝑇 )� (14)
𝑚𝑚𝑎𝑎𝑚𝑚−1 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1
𝑇𝑇 −𝑇𝑇
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1
Finally, if G > G and T > T :
max max
𝐺𝐺−𝐺𝐺
𝑚𝑚𝑎𝑎𝑚𝑚−1
𝜂𝜂(𝐺𝐺,𝑇𝑇 ) =𝜂𝜂(𝐺𝐺 ,𝑇𝑇 ) + �𝜂𝜂(𝐺𝐺 ,𝑇𝑇 )−𝜂𝜂(𝐺𝐺 ,𝑇𝑇 )� (15)
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1 𝑚𝑚𝑎𝑎𝑚𝑚
𝐺𝐺 −𝐺𝐺
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1
𝑇𝑇−𝑇𝑇
𝑚𝑚𝑎𝑎𝑚𝑚−1
( ) ( ) ( ) ( )
𝜂𝜂𝐺𝐺 ,𝑇𝑇 =𝜂𝜂𝐺𝐺 ,𝑇𝑇 + �𝜂𝜂𝐺𝐺 ,𝑇𝑇 −𝜂𝜂𝐺𝐺 ,𝑇𝑇 � (16)
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1
𝑇𝑇 −𝑇𝑇
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚−1
𝜂𝜂(𝐺𝐺,𝑇𝑇) =𝜂𝜂(𝐺𝐺,𝑇𝑇 ) + 𝜂𝜂(𝐺𝐺 ,𝑇𝑇)−𝜂𝜂(𝐺𝐺 ,𝑇𝑇 ) (17)
𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚 𝑚𝑚𝑎𝑎𝑚𝑚
7.6 Calculation of hourly module energy output
The energy output E of the module in the time period j (1 h) is:
mod,j
𝐸𝐸 =𝑃𝑃 (𝐺𝐺 ,𝑇𝑇 )∙ 1 ℎ𝑜𝑜𝑜𝑜𝑜𝑜 (18)
mod,j mod,j 𝑐𝑐𝑐𝑐𝑐𝑐𝑐𝑐,𝑗𝑗 𝑚𝑚𝑐𝑐𝑑𝑑,𝑗𝑗
7.7 Calculation of annual module energy output
The energy produced by the module over one year is determined as t
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