Experimental and Simulated Performance of Optimal Control of Building Thermal Storage.
Experimental and Simulated Performance of Optimal
Control of Building Thermal Storage.
(1199 K)
Morris, F. B.; Braun, J. E.; Treado, S. J.
3776;
ASHRAE Transactions, Vol. 100, No. 1, 402-414, January
1994.
Keywords:
storage; building control; experiments; test facilities;
simulation; optimal control strategies; energy savings;
peak demand reductions
Abstract:
Dynamic building control involves utilizing the thermal
storage potential of building mass to reduce cooling
costs. Previous simulation studies have shown that both
energy use and peak electrical demand can be
significantly reduced using dynamic building control
instead of conventional night setback control for many
applications. In this study, optimal dynamic building
control strategies were compared with night setback
control through experiments at a test facility
representative of a room in a large office building.
Two optimal dynamic building control strategies were
considered: minimum total energy costs and minimum peak
electrical demand. These control strategies were
determined through simulation of the test facility. The
experiments showed that up to 51% of the total cooling
load could be shifted to off-peak hours through optimal
control. The reduction in the peak cooling load was
found to be as much as 40%. For the test conditions,
estimates of electrical energy and demand savings were
determined through simulations and found to be 10% and
38%, respectively. Occupant thermal comfort was also
measured during the experiments and maintained within
acceptable limits for all control strategies tested.
Measured cooling loads compare well with those predicted
by the simulation and validate the simulation method.
Additional simulations were conducted to study the
effect of ambient conditions, utility rate structure,
and the coupling between the zone and the ambient
through exterior walls on the savings potential of
dynamic building control. The results of this research
demonstrate the tremendous potential associated with
optimal control of building thermal storage.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899