Solar Heat for Industrial Processes (SHIP) is currently at the early stages of development. However, it is regarded to be one of the most potential fields for solar thermal application. Currently, 120 operating solar thermal systems for process heat are reported worldwide, with a total capacity of about 88 MWth (125,000 m2). The first applications have been of an experimental nature with relatively small scale. In recent years, significantly bigger solar thermal fields have been applied and are currently in the project pipeline. There is great potential for market and technological developments, as 28% of the overall energy demand in the EU27 countries originates in the industrial sector, majority of this is heat of below 250oC.
According to a study (Ecoheatcool 2006), around 30% of the total industrial heat demand is required at temperatures below 100oC and 57% of this demand is required at temperatures below 400oC. The heat demand below 100oC could theoretically be met with solar thermal systems using current technologies, if suitable integration of the solar thermal system can be identified. With technological development, more and more medium temperature applications, up to 400oC, will also become market feasible.
In several specific industry sectors, such as food, wine and beverages, transport equipment, machinery, textiles, pulp and paper, the share of heat demand at low and medium temperatures (below 250oC) is around 60% (POSHIP 2001). Tapping into this potential would provide a significant solar contribution to industrial energy requirements.
The methodology which has been developed in order to realize thermal energy supply in industry with minimal greenhouse gas emissions is based on a three step approach:
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Technological Optimization of the processes (e.g. increased heat and mass transfer, lower the process temperature) and solar thermal system (e.g. operation of solar field, integration schemes, control, safety issues etc.)
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System Optimization (enhancing energy efficiency using e.g. Pinch Analysis for heat exchanger network for a total production site)
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Integration of renewable energy/solar thermal energy (based on exergetic considerations)