Analytical and comparative testing of EnergyPlus using IEA HVAC BESTEST E100-E200 test suite

Abstract The EnergyPlus building energy simulation software has been tested using the IEA HVAC BESTEST E100–E200 series of tests. The volume 1 final report for the International Energy Agency (IEA) solar heating and cooling programme task 22 building energy simulation test and diagnostic method for heating, ventilating, and air conditioning equipment models (HVAC BESTEST) was recently published in January 2002. HVAC BESTEST is a series of steady-state tests for a single-zone DX cooling system. Cases range from dry to wet coil, low to high part load, and low to high temperatures. This published test suite includes three sets of analytical solutions and results from several other simulation programs for comparison. This test suite was initially used to test EnergyPlus beginning with beta versions prior to its official public release, and it is also applied as an ongoing quality assurance test. The application of these tests proved to be very useful in several ways: • revealed input model shortcomings, which resulted in new user inputs being added; • revealed reporting errors which were fixed; • revealed algorithmic errors which were fixed; • revealed algorithmic shortcomings which were improved or eliminated through the use of more rigorous calculations for certain components; • in later versions, caught newly introduced bugs before public release of updates. Overall, the application of this test suite has been extremely useful in debugging and verifying the DX cooling algorithms in EnergyPlus. This paper summarizes the difficulties encountered and the benefits gained in applying the tests.