Inverter sizing strategies for grid-connected photovoltaic (PV) systems
often do not take into account site-dependent peculiarities of ambient
temperature, inverter operating temperature and solar irradiation
distribution characteristics. The operating temperature affects PV
modules and inverters in different ways and PV systems will hardly
ever have a DC output equal to or above their STC-rated nominal power.
Inverters are usually sized with a nominal AC output power some 30%
(sometimes even more) below the PV array nominal power. In this paper,
we show that this practice might lead to considerable energy losses,
especially in the case of PV technologies with high temperature coefficients
of power operating at sites with cold climates and of PV technologies
with low temperature coefficients of power operating at sites with
warm climates and an energy distribution of sunlight shifted to higher
irradiation levels. In energy markets where PV kW h s are paid premium
tariffs, like in Germany, energy yield optimization might result
in a favorable payback of the extra capital invested in a larger
inverter. This paper discusses how the time resolution of solar radiation
data influences the correct sizing of PV plants. We demonstrate that
using instant (10 s) irradiation values instead of average hourly
irradiation values leads to considerable differences in optimum inverter
sizing. When calculating inverter yearly efficiency values using
both, hourly averages and 1-min averages, we can show that with increased
time resolution of solar irradiation data there are higher calculated
losses due to inverter undersizing. This reveals that hourly averages
hide important irradiation peaks that need to be considered. We performed
these calculations for data sets from pyranometer readings from Freiburg
(48 N, Germany) and Florianopolis (27 S, Brazil) to further show
the peculiarities of the site-dependent distribution of irradiation
levels and its effects on inverter sizing.
%0 Journal Article
%1 Burger.Ruether2006
%A Burger, B.
%A Rüther, R.
%D 2006
%J Solar Energy
%K Inverter PV grid-connected sizing systems,
%P 32--45
%T Inverter sizing of grid-connected photovoltaic systems in the light
of local solar resource distribution characteristics and temperature
%V 80
%X Inverter sizing strategies for grid-connected photovoltaic (PV) systems
often do not take into account site-dependent peculiarities of ambient
temperature, inverter operating temperature and solar irradiation
distribution characteristics. The operating temperature affects PV
modules and inverters in different ways and PV systems will hardly
ever have a DC output equal to or above their STC-rated nominal power.
Inverters are usually sized with a nominal AC output power some 30%
(sometimes even more) below the PV array nominal power. In this paper,
we show that this practice might lead to considerable energy losses,
especially in the case of PV technologies with high temperature coefficients
of power operating at sites with cold climates and of PV technologies
with low temperature coefficients of power operating at sites with
warm climates and an energy distribution of sunlight shifted to higher
irradiation levels. In energy markets where PV kW h s are paid premium
tariffs, like in Germany, energy yield optimization might result
in a favorable payback of the extra capital invested in a larger
inverter. This paper discusses how the time resolution of solar radiation
data influences the correct sizing of PV plants. We demonstrate that
using instant (10 s) irradiation values instead of average hourly
irradiation values leads to considerable differences in optimum inverter
sizing. When calculating inverter yearly efficiency values using
both, hourly averages and 1-min averages, we can show that with increased
time resolution of solar irradiation data there are higher calculated
losses due to inverter undersizing. This reveals that hourly averages
hide important irradiation peaks that need to be considered. We performed
these calculations for data sets from pyranometer readings from Freiburg
(48 N, Germany) and Florianopolis (27 S, Brazil) to further show
the peculiarities of the site-dependent distribution of irradiation
levels and its effects on inverter sizing.
@article{Burger.Ruether2006,
abstract = {Inverter sizing strategies for grid-connected photovoltaic (PV) systems
often do not take into account site-dependent peculiarities of ambient
temperature, inverter operating temperature and solar irradiation
distribution characteristics. The operating temperature affects PV
modules and inverters in different ways and PV systems will hardly
ever have a DC output equal to or above their STC-rated nominal power.
Inverters are usually sized with a nominal AC output power some 30%
(sometimes even more) below the PV array nominal power. In this paper,
we show that this practice might lead to considerable energy losses,
especially in the case of PV technologies with high temperature coefficients
of power operating at sites with cold climates and of PV technologies
with low temperature coefficients of power operating at sites with
warm climates and an energy distribution of sunlight shifted to higher
irradiation levels. In energy markets where PV kW h s are paid premium
tariffs, like in Germany, energy yield optimization might result
in a favorable payback of the extra capital invested in a larger
inverter. This paper discusses how the time resolution of solar radiation
data influences the correct sizing of PV plants. We demonstrate that
using instant (10 s) irradiation values instead of average hourly
irradiation values leads to considerable differences in optimum inverter
sizing. When calculating inverter yearly efficiency values using
both, hourly averages and 1-min averages, we can show that with increased
time resolution of solar irradiation data there are higher calculated
losses due to inverter undersizing. This reveals that hourly averages
hide important irradiation peaks that need to be considered. We performed
these calculations for data sets from pyranometer readings from Freiburg
(48 N, Germany) and Florianopolis (27 S, Brazil) to further show
the peculiarities of the site-dependent distribution of irradiation
levels and its effects on inverter sizing.},
added-at = {2011-09-01T13:26:03.000+0200},
author = {Burger, B. and Rüther, R.},
biburl = {https://www.bibsonomy.org/bibtex/22abbd76df687a0db2bcbe045adf3dd6e/procomun},
interhash = {70eeeab19ffaa68facb33db42a0d5df8},
intrahash = {2abbd76df687a0db2bcbe045adf3dd6e},
journal = {Solar Energy},
keywords = {Inverter PV grid-connected sizing systems,},
owner = {oscar},
pages = {32--45},
refid = {Burger.Rüther2006},
timestamp = {2011-09-02T08:25:25.000+0200},
title = {Inverter sizing of grid-connected photovoltaic systems in the light
of local solar resource distribution characteristics and temperature},
volume = 80,
year = 2006
}