Optimal renewable energy systems for industries in rural regions

Background:Energy systems for smart regions will require on the one hand a much higher share of renewable
energy sources for heat and electricity and on the other hand a high standard integration of industry and utilities
supplying households and businesses. As energy options become more diverse, integration of industry into the
energy provision for settlements and vice versa become important from an economic and ecological point of view.
A particular problem is the supply of bio-energy to large industrial complexes as this requires considerable efforts
to manage resource provision as well as constructing smart systems to utilise available resources without posing
direct competition to the supply of food and feed.
Methods:This paper will discuss the application of Process Network Synthesis (PNS) using the P-Graph method as
a tool to generate optimal energy systems supplying industry with energy based on bio-resources in the context of
a rural region and small urban centre. Application of these methods to a real life case study in an industrial city in
rural context (Weiz in Austria) will be discussed from the viewpoint of general lessons to be learned from the design
of complex energy systems linking different energy provision sources to supply industry and residential areas in a
systemic way with energy.
Results:The synthesis resulted in a basic optimal solution containing the economically most feasible regional
energy-technology network. Scenarios show differences in resource use and the creation of revenue. Anaerobic
digestion, CHP and wood gasification appear for most of the scenarios.
Conclusions:The case study shows that a support of large consumers with sustainable regional energy systems
can already be realised with current market prices. Heat demand outside industry critically influences the economic
success of regional technology networks. Feed-in tariffs remain as a key factor for the creation of revenue. As
regional parameters like resource availability, prices and locations where technologies could be situated change, the
economic success also changes. Price limits and stable technologies can be identified.