Economic model predictive control of space heating and dynamic solar shading

Abstract

Dynamic solar shading devices are an effective mean to avoid overheating in buildings due to excessive solar heat gains. They can also be used to affect the heat balance of buildings; they can be on e.g. during nighttime to reduce space heating or retracted to increase night cooling. The shading control system can utilize this feature to obtain energy cost savings and reduce peak consumption. However, it is difficult to define optimal rule-based control strategies that minimize overheating and energy costs simultaneously. In this paper, we therefore propose an economic model predictive control (E-MPC) scheme for space heating where solar shading is included as an additional control variable. The proposed scheme employs black-box models, as they are ‘cheap’ to create from data; this is important for a widespread deployment of E-MPC in practice. The study was based on co-simulation experiments where EnergyPlus models represented the actual building and it was hereby demonstrated that the proposed E-MPC outperformed two rule-based controllers with respect to reducing overheating, energy costs and peak consumption. Shading also turned out to be valuable for north facing rooms where it reduced costs and peak consumptions compared to an MPC without shading. The energy-related benefits of the proposed E-MPC scheme can be regarded as ‘an added value’ that can be used for economic justification of an investment in dynamic solar shading devices.