Environmental Engineering Reference
In-Depth Information
1.2 Solar Thermal Energy
In solar thermal power plants, sunlight is focused onto an absorber by giant mirrors,
which then transform the light into thermal energy.
61
By intensifying the sunlight
s
concentration, a suitable fluid is heated up.
62
Thermo oil would be an example of a
fluid that can reach a temperature of 400
C.
63
The heat is then used to run a thermal
engine, e.g. a steam engine to produce electricity.
64
As illustrated by the picture
below, there are three different types of solar thermal power plants: firstly, the solar
tower; secondly, the parabolic channel; and finally, the paraboloid.
65
The main advantage of solar thermal power plants is that they allow thermal
energy (heat storage) to be stored more easily and more efficiently than electric-
ity.
66
Studies have illustrated that the efficiency of solar thermal power plants
increases from 20 to 30 % through heat storage. Such a plant could therefore
operate as a base load power station.
67
The possibility of storing the thermal energy
would also allow the power plant to operate at all times.
68
CSP
'
s functionality has
also been proven in various plants all over the world, and recently also in Africa.
69
Modern transmission lines (HVDC) enable the energy to be transported to Europe
from North Africa, with only a loss of 10-15 %.
70
Calculations predict a total investment of 400 billion Euros within the next
40 years.
71
To achieve this aim, the EU is backing the construction of undersea
cables in the Mediterranean Sea and other possible subsidies.
72
Facilities in Spain
had production costs of 14 cents/kWh, but due the greater solar radiation within
North Africa the price might be reduced to 9.5 cents/kWh.
73
Further reductions
could take place because of night storage and connected desalination of 3-5 cents.
74
Transport costs are around 2 cents/kWh to Europe.
75
In Spain, the feed-in compen-
sation was around 18-22 cents/kWh (including possible state investments).
76
'
61
Deutsch and Hobohm (
2010
), 54 (55); D
¨
ren (
2008
), 6 (10).
62
Deutsche Physikalische Gesellschaft e.V. (
2005
), 80; Deutsch and Hobohm (
2010
), 54 (55).
63
Deutsche Physikalische Gesellschaft e.V. (
2005
), 81.
64
Sch
¨
fer (
2008
), 11 (15); cf. Deutsch and Hobohm (
2010
), 54 (55); Deutsche Physikalische
Gesellschaft e.V. (
2005
), 80.
65
Deutsch and Hobohm (
2010
), 54 (55); Deutsche Physikalische Gesellschaft e.V. (
2005
), 80.
66
Sch
¨
fer (
2008
), 11 (14).
67
Sch
¨
fer (
2008
), 11 (14).
68
Sch
¨
ssler (
2008
), 221 (221); D
¨
ren (
2008
), 6 (10).
69
Sch
¨
ssler (
2008
), 221 (225).
70
D¨ren (
2008
), 6 (10).
71
Biobay.de (
2009
).
72
Biobay.de (
2009
).
73
Winker and Preußner (
2008
), 34 (35); Starting costs are higher than operating costs later on, in:
Berger (
2003
), 65 (65).
74
Winker and Preußner (
2008
), 34 (35).
75
Winker and Preußner (
2008
), 34 (36).
76
Winker and Preußner (
2008
), 34 (35).
