Optimization method for minimizing annual energy, peak energy demand, and annual energy cost through use of building thermal storage

• Published in: ASHRAE TRANS Vol. 108; no. 1; pp. 43 - 53
• Main Author: Nagai, T
• Format: Journal Article Conference Proceeding
• Language: English
• Published: 01.01.2002
• Subjects: Algorithms; Atmospheric humidity; Costs; Dynamic programming; Heat storage; Office buildings; Optimal control systems; Optimization; Specific heat; Thermal load
• ISSN: 0001-2505

The thermal capacity of the building envelope has an effect of leveling heating and cooling load. This paper describes a calculation method for optimal dynamic control utilizing the thermal effect to minimize specific objective functions, namely: annual energy consumption; annual peak energy demand through a year; and annual energy cost. Dynamic programming is employed as an optimization algorithm for the first two objective functions. The last is dealt with as a multi-objective optimization composed of two criteria, i.e., annual energy consumption and peak energy demand, in order to consider demand charge as well as per unit rate. Dynamic programming tends to require excessive computational efforts. This paper also presents new calculation procedures to ease this computational difficulty. A calculation example, assuming an office building in Japan is equipped with an electric-driven packaged air conditioner, is described to present optimal control for each season and the reduced amount of annual energy, etc.