SolarGrids

Today about 20% of the residential heat demand in Austria is covered with district heat. Hence, the integration of solar thermal systems in heating grids could hold a large potential for the future deployment of solar heat generation. However, especially in urban areas heating grids are often supplied with waste heat from highly efficient CHP or waste incineration plants, and solar thermal energy is usually available during times of low demand.

Apart from that, it needs to be taken into account that due to decreasing heat loads of the building stock and climate change, framework conditions for heat grids are likely to change substantially in the years and decades to come.

The core question of this project is:

• What are the prospects for the integration of solar thermal systems in district heating and cooling networks in a future, transformed low-carbon energy system? With regard to changing framework conditions in a low-carbon energy system largely based on renewable energy technologies, the following aspects are investigated in detail:
• How do building refurbishment and – as a consequence – decreasing heat densities in regions supplied with district heat influence these prospects?
• What are the impacts of a changing structure of power generation (including higher shares of volatile generation with wind power and photovoltaic), especially with regard to the waste heat supply from CHP plants?

Based on a comprehensive description and categorization of Austrian heating networks with regard to size and structure, an assessment of technical options for the integration of solar thermal systems is carried out with the simulation tools TRNSYS and SIMPLEX.
Consecutively, the effects on and mutual influence with the heat market and the power system are analyzed with a bottom-up model of the Austrian building stock and district heating grids, and an optimization model of the Austrian power system, respectively. Both short-term and long-term effects up to 2050 are considered. The results are compared with international case studies, and business models are assessed. Finally, conclusions about options for energy policies are derived. An intensive involvement of stakeholder is considered as an integral part of the project.

Coordination:
TU-Wien www.tuwien.ac.at
Energy Economics Group www.eeg.tuwien.ac.at

Further information about the project finds her: www.eeg.tuwien.ac.at

www.eeg.tuwien.ac.at