Environmental Engineering Reference
In-Depth Information
cases such systems directly supply direct current consumers. They are typically
applied for camping and leisure as well as for motor vehicle operation; further-
more, solar home systems are applied for basic power supply in rural areas of
developing and emerging countries. Yet, there are also systems which are pro-
vided with an inverter to supply standard alternating current consumers.
Hybrid systems are applied if a reliable energy supply of large energy quanti-
ties independent of season and weather conditions is required. This is especially
true for latitudes, such as Central Europe, characterised by high radiation differ-
ences between the summer and winter months. For this purpose different power
generators are coupled complement to each other in terms of time and energy. The
most commonly applied additional power generator is a Diesel engine equipped
with a generator (called a Diesel generator). Such Diesel generators are turned on
when the battery state of charge is too low due to insufficient solar radiation or
excessive power demand. The Diesel generator is operated based on the fossil
energy resource. This has the advantage that Diesel fuel can easily be stored. Ac-
cording to the respective system concept batteries may either be recharged or
direct current from the Diesel generator can be directly provided to consumers.
Fig. 6.26 shows the example of a block diagram including a motor generator (be-
sides Diesel engines also (bio-)gas or bio fuel-fired engines may be used) and a
wind energy converter besides the photovoltaic generator. Wind energy convert-
ers and solar energy systems complement each other well at many sites with re-
gard to seasonal and weather-related fluctuations. For instance, in Central Europe
wind resources complement solar radiation in fall and winter. Furthermore, during
prolonged periods of bad weather, often increased wind resources are available.
Motor generators which are only turned on in times of high demand offer addi-
tional flexibility in terms of system operation, ensure more smooth operation and
thus a prolonged service life of the battery.
Direct current
bus-bar
Alternating current
bus-bar
∼
=
=
PV
DC-consumer
AC-consumer
∼
∼
∼
=
=
WG
=
DC/AC
Inverter
Windmill
Battery
=
∼
MG
∼
=
Motorgen
.
AC/DC
∼
Fig. 6.26
Block diagram of a hybrid system with direct current and alternating current bus-
bar (PV photovoltaic generator, MG motor generator, WG wind generator, DC direct cur-
rent, AC alternating current)
Search WWH ::
Custom Search