Simulating control strategies of electrochromic windows: Impacts on indoor climate and energy use in an office building.
Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
The building sector is a one of modern society’s biggest users of energy. In turn, a building’s windows have a significant impact on its energy usage. Electrochromic windows have a thin film on one of the panes, designed to variably change the tint of the window. Thereby the solar heat gain, needed internal lighting and building energy utilization are varied.
This thesis uses the simulation software IDA ICE 4.5 to simulate control scenarios for electrochromic windows. The goal is to examine how well this software can simulate the windows as well as to explore the potential of creating custom control algorithms for the windows. The impact of the control scenarios on the energy consumption of a building is then analyzed. The reference case for the simulations is a regular window with blinds, where the blinds are controlled with a built-in algorithm. The simulated control scenarios for the electrochromic windows were; the built-in algorithm, always off, always on, operative temperature, workplane illuminance, and light levels at the façade and window.
In the simulation results the energy usage was slightly lowered with the electrochromic windows using the built-in control compared to the reference case. The custom algorithm that uses the light levels at the façade and window was designed to improve upon the built-in algorithm with additional adjustable settings. However, this custom algorithm produced similar results to the built-in algorithm and the majority of the additional settings had little impact on the energy usage. The other custom designed algorithms measured workplane illuminance and operative temperature to control the shading. These showed an overall decrease in the energy usage compared to the reference case.
The IDA ICE software has potential for further simulations of a building’s energy usage while using electrochromic windows. Further investigation is needed to determine if the simulation resolution is high enough to accurately depict the effect these settings might have on the energy usage.
Place, publisher, year, edition, pages
2013. , 40 p.
UPTEC ES, ISSN 1650-8300 ; 13 044
electrochromic, windows, simulating, IDA ICE, smart windows, control strategies
IdentifiersURN: urn:nbn:se:uu:diva-212595OAI: oai:DiVA.org:uu-212595DiVA: diva2:678505
Master Programme in Energy Systems Engineering
Jönsson, PetraNilsson, Annica