Cost Analysis of Simple Phase Change Material-Enhanced Building Envelopes in Southern U.S. Climates.

摘要

Traditionally, the thermal design of building envelope assemblies is based on steady-state energy flows. In practice, however, building envelopes are subject to varying environmental conditions. Design work to support the development of very low-energy homes shows that the conventional insulations may not always be the most cost-effective energy solution for improving the thermal performance of the building envelope. This report focuses on building envelopes that have been enhanced with phase change materials (PCMs), which can simultaneously reduce total cooling loads and shift peak-hour loads. Researchers at the Fraunhofer Center for Sustainable Energy Systems performed an economic analysis to evaluate the cost effectiveness of simple PCM-enhanced building envelopes and determined the target cost levels at which PCMs can be cost competitive with conventional building thermal insulations. The study team selected two basic PCM applications for analysis: dispersed PCM applications and simple building board products using concentrated PCMs. In addition to describing Fraunhofers work, this report summarizes the results of previous experimental and theoretical studies that have been conducted in North America to understand the performance of PCM-enhanced building envelopes. The study team used these results as performance benchmarks for different PCM configurations that were tested in the United States for different building applications. This work did not, however, seek to optimize the configurations of PCMs.