Progressive design practices are increasingly cognisant of the potential of building energy simulation to assist the delivery of energy efficient, sustainable buildings. However, the success of any building performance assessment hinges on the capabilities of the tool; the collective competences of the team formed to apply it; and, crucially, the existence of an in-house framework within which simulation can be applied with confidence (McElroy and Clarke 1999).

This paper describes the use of transient building performance simulation in order to develop design guidelines for educational buildings in Turkiye. The premise of the work is that design decisions taken during early stages of the building process have a large impact on the performance of the resulting building and hence need solid underpinning. Yet straightforward application of building performance in these early stages has proven to be difficult.

Recent legislation and building regulations have aiming to reduce the energy demands of buildings and include renewable based micro-generation technologies.

EnergyPlus models follow fundamental heat balance principles very closely in almost all aspects of the program. However, the simulation of building surface constructions has relied on a transfer function transformation carried over from BLAST. This has all the usual restrictions of a transformation-based solution: constant properties, and fixed values of some parameters.

Over the last three decades the use of building performance simulation (BPS) tools has increased but its ability to support building design is still limited. State of the art BPS tools have the potential to be used more extensively during the entire design process if their current capabilities are expanded.

Appraisal of modern performance-based energy codes, as well as heating, ventilation, airconditioning and refrigeration (HVAC/R) system*design require use of an integrated building and system performance simulation program. However, the required scope of the modeling library of such integrated tools often goes beyond those offered in available simulation programs. One remedy for this situation would be to develop the required models in an existing simulation program.

The main objective of this paper is to establish a set of test cases for analytical verifications and intermodel comparisons of ground heat exchanger (GHX) models used in building simulation programs. Several test cases are suggested. They range from steady-state heat rejection in a single borehole to varying hourly loads with large yearly thermal imbalance in multiple borehole configurations.

There are several ways to attempt to model a building and its heat gains from external sources as well as internal ones in order to evaluate a proper operation and also audit retrofits actions. These models apply various techniques varying from simple regression to more physically grounded models.