Solar energy in building renovation - Results and experience of international demonstration buildings

The aim of a renovation design process is generally not to find the cheapest solution to maintain a proper building function. Renovation deals with a balance of maintenance, improvement, and architectural topics within a given budget. The analysis of the demonstration projects proves that solar technologies have their place, financially, technically and architecturally, as part of integrated renovation concepts. Many of the demonstration projects evaluated tend to be `solar dominated' as the analysis of the technology is a main topic. Solar energy systems offer the potential to cut fossil fuel consumption significantly. However, such reductions can only be realized by solar systems that are readily adaptable to both existing and newer buildings. Issues addressed by participants in the recent Solar Heating and Cooling Programme of the International Energy Agency Task 20 Solar Energy in Building Renovation workshop are discussed, including techniques for the performance assessment of existing solar renovation projects. Simulation techniques were used to evaluate several promising energy saving concepts. Findings are presented from the implementation of 14 demonstration projects that largely focussed on multifamily dwellings featuring solar concepts. Different technical, economic, and building physics issues for solar collectors, glazed balconies, and solar wells are discussed.