Window control system with photodiode illumination sensors
A smart window controller includes circuitry configured to establish a representative model of one or more building zones based on occupancy, construction, lighting, or cooling properties of a building. A lighting control strategy is implemented for the one or more building zones based on the representative model or one or more user preferences input at a first user interface screen of an external device. Automatic operations of one or more smart windows, cooling systems, or artificial lighting systems are controlled based on trigger points associated with the lighting control strategy, and a performance level of the lighting control strategy for the one or more building zones is determined based on one or more predetermined financial metrics.
1. A smart window control system, comprising:
a wireless mobile device having a message screen to display text messages,
a plurality of photodiode illumination sensors disposed inside a building, wherein the photodiode illumination sensors are deployed in pairs in perimeter zones of the building, each perimeter zone having one or more windows, and
a smart window control device comprising a processor having circuitry configured to:
establish a representative model of one or more building zones based on occupancy, construction, lighting, or cooling properties of the building,
implement a lighting control strategy for the one or more building zones based on the representative model or one or more user preferences input at a first user interface screen of an external device,
control automatic operations of one or more electrochromatic smart windows by varying a voltage applied to a stack of electrochromatic coating layers, or artificial lighting systems by modifying a fractional input power in discrete steps based on trigger points associated with the lighting control strategy responsive to daylight measurements from the plurality of the photodiode illumination sensors, and
determine with the circuitry a performance level of the lighting control strategy for the one or more building zones based on one or more predetermined financial metrics that include a comparison of total building energy consumption to a threshold, wherein
the circuitry is further configured to determine a comfort score and an energy savings score indicating a relative importance of visual comfort and energy savings for the one or more building zones based on the representative model of the one or more building zones or the one or more user preferences,
the circuitry is further configured to implement a daylight control strategy as the lighting control strategy when the energy savings score is greater than an energy savings threshold or the comfort score is lower than a visual comfort threshold, and
the circuitry is further configured to implement a solar control strategy or a glare control strategy as the lighting control strategy when the energy savings score is less than or equal to an energy savings threshold and the comfort score is greater than or equal to a visual comfort threshold,
wherein the predetermined financial metrics include a predetermined payback period associated one or more building components based on a current energy costs, price of the one or more building components, and one or more financial health attributes of a building,
wherein the circuitry is further configured to output a text warning on the message screen of the wireless mobile device when an amount of energy savings associated with the one or more smart windows over a predetermined period of time does not meet the predetermined payback period associated with the one or more building components, and
wherein the wireless mobile device is wirelessly connected to the smart window control device through a wireless network.
2. The device of claim 1 , wherein the circuitry is further configured to identify the one or more photodiode illumination sensors associated with each of the one or more perimeter zones.
3. The device of claim 2 , wherein the circuitry is further configured to determine an impact weighting factor associated with each of the one or more photodiode illumination sensors based on at least one of sensor value, time of day, or time of year.
4. The device of claim 1 , wherein the circuitry is further configured to define the one or more building zones based on a layout of heating or cooling system controls within a building.
5. The device of claim 1 , wherein the circuitry is further configured to determine an illumination deficit for the one or more building zones corresponding to a difference between a target illuminance and an amount of daylight illuminance from the one or more electrochromatic smart windows.
6. The device of claim 1 , wherein the processor having circuitry is an application specific integrated circuit.