In this paper energy balance simulations were performed for one electrochromic and two static solar control windows. The visible transmittance of the electrochromic layer was modulated using four different control strategies, one for energy optimization and three based on incident solar radiation limits during office hours and energy optimization during unoccupied hours. This paper does not provide an optimized control algorithm, but general trends for a few control strategies are described. For example adjusting the control strategy to the time of the day and seasonal solar irradiance and temperature changes, have been shown beneficial from an energy perspective. It is clear that the switchability of electrochromic coatings is advantageous, but that multiple factors, such as visual comfort, user needs, climate, and orientation, have to be considered for optimum performance. In this paper it was shown that a simple window simulation tool can be used to estimate how some of these factors affect the energy balance.

References

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