The Methods of 2020 for Building Envelope and HVAC Systems Simulation-Will the Present Tools Survive?

Computer simulation of buildings, HVAC and control systems is likely to grow in importance in the years to come. The fundamentals of the computer methods in use today were primarily developed during the seventies and early eighties. They were optimized to enable full-year whole-building simulations on available hardware. Consequently, they are highly specialized and very difficult to modify in order to meet the needs posed by new users and technologies. On the other hand, they have been proven to do the job and are well-known to developers and end-users. In this paper, we compare the traditional methods to a new generation of computer modeling tools: equation based methods. These have the capacity to model virtually any system that can be described with equations and are thus able to grow in arbitrary new directions as needs evolve. The main obstacles have up until recently been availability of development tools, difficulty of use, lower execution speed and frequent crashes. The paper discusses these and other issues involved.