Renewable Energy in Industrial Applications – an ... - Unido

SOLAR THERMAL SYSTEMS
Figure 11
Parabolic trough field, El NASR Pharmaceutical Chemicals, Egypt
(Weiss and Mauthner, 2010)
Different solar technologies have different
investment costs per unit of capacity, and
different levels of capability in terms of thermal
output. Flat plate collectors are the cheapest
technology, but they can only be used to heat
loads to around 70oC. Vacuum tubes or parabolic
mirrors in combination with a suitable heat
energy carrier can reach 120oC to 400oC.
Successful tests have been carried out using
solar energy to achieve temperatures sufficient to
produce pure metals from ore. But the cost and
technical challenges involved in upscaling these
tests make the widespread application of solar
heat at temperature levels above 400oC unlikely
before 2050.
Given the profile of temperature needs in
industry (Figure 12), most process heat demand
can be met using relatively low cost flat plate
and vacuum tube collectors. Only 8% (0.5 EJ/yr)
of the estimated 5.6 EJ/yr of solar thermal energy
in 2050 will require the use of CSP technologies;
the rest can be achieved using flat pane
collectors and evacuated tube collectors.
The economic competitiveness of solar thermal
energy in industry will be very positively affected
by high carbon prices. Among renewable
technologies, solar has an advantage over
bioenergy as it is not exposed to feedstock price
volatility. To increase competitiveness, the capital
cost of solar technologies needs to be reduced
through learning, starting with the deployment of
solar thermal systems in selected sectors in
regions where solar radiation is abundant and as
constant as possible throughout the year, such
as for example in the dairy sector in India
(discussed further in Annex 4). The deployment
of solar thermal systems where they are already
competitive today will facilitate the diffusion of
economically attractive, reliable, industrial-scale
solar thermal systems to other regions and
sectors, as learning effects and economies of
scale come into play.
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