Control method for tintable windows

1. An apparatus for controlling tint of one or more tintable windows disposed in a building, the apparatus comprising at least one controller circuitry, wherein the at least one controller circuitry is configured to:

(a) communicatively couple to at least one sensor disposed externally to the building;

(b) receive, or direct receipt of, measurements from the at least one sensor to generate real-time irradiance values;

(c) calculate, or direct calculation of, a tint level for the one or more tintable windows based at least in part on the real-time irradiance values and a clear sky irradiance;

(d) send tint instructions, or direct sending of tint instructions, to transition tint of the one or more tintable windows to the calculated tint level.

2. The apparatus of claim 1 , wherein the at least one controller circuitry is configured to calculate, or direct calculation of, an inside irradiance in a room of the building.

3. The apparatus of claim 2 , wherein the at least one controller circuitry is configured to calculate, or direct calculation of, the inside irradiance by predicting the clear sky irradiance.

4. The apparatus of claim 1 , wherein the at least one controller circuitry is configured to calculate, or direct calculation of, the tint level using a feedback control scheme, which feedback uses the measurements from the at least one sensor.

5. The apparatus of claim 1 , wherein the at least one controller circuitry is configured to calculate, or direct calculation of, the tint level by determining whether the real-time irradiance values are less than the clear sky irradiance.

6. The apparatus of claim 5 , wherein if the real-time irradiance values are less than the clear sky irradiance, the tint level is made lighter.

7. The apparatus of claim 5 , wherein if the real-time irradiance values are less than the clear sky irradiance, then the tint level is made lighter incrementally until the tint level is equal to or less than a threshold.

8. The apparatus of claim 5 , wherein if the real-time irradiance values are not less than the clear sky irradiance, the tint level is made darker.

9. The apparatus of claim 1 , wherein the at least one controller circuitry is configured to dynamically determine, or direct a determination of, an effect of a surrounding environment to the building.

10. A method of controlling tint of one or more tintable windows disposed in a building, the method comprising:

(a) using measurements from at least one sensor to generate real-time irradiance values, wherein the at least one sensor is disposed externally to the building;

(b) calculating a tint level for the one or more tintable windows based at least in part on the real-time irradiance values and a clear sky irradiance; and

(c) transitioning tint of the one or more tintable windows to the calculated tint level.

11. The method of claim 10 , further comprising calculating an inside irradiance in a room in the building.

12. The method of claim 11 , wherein the calculation of the inside irradiance comprises predicting the clear sky irradiance.

13. The method of claim 10 , wherein the calculation of the tint level comprises using feedback, wherein the feedback uses the measurements from the at least one sensor.

14. The method of claim 10 , wherein the calculation of the tint level comprises a determination of whether the real-time irradiance values are less than the clear sky irradiance.

15. The method of claim 14 , wherein if the real-time irradiance values are less than the clear sky irradiance, then the tint level is made lighter.

16. The method of claim 14 , wherein if the real-time irradiance values are less than the clear sky irradiance, then the tint level is made lighter incrementally until the tint level is equal to or less than a threshold.

17. The method of claim 14 , wherein if the real-time irradiance values are not less than the clear sky irradiance, the tint level is made darker.

18. The method of claim 10 , further comprising dynamically determining an effect of a surrounding environment to the building.

19. A system for controlling tint of one or more tintable windows disposed in a building, the system comprising a network configured to:

a. communicatively couple to at least one sensor disposed externally to the building and to the one or more tintable windows;

b. transmit measurements from the at least one sensor;

c. transmit calculation of a tint level based at least in part on (i) real-time irradiance values generated using the measurements from the at least one sensor disposed and (ii) a clear sky irradiance; and

d. transmit tint instructions for tinting the one or more tintable windows to the tint level.

20. The system of claim 19 , wherein the network is further configured to transmit a calculation of an inside irradiance in a room in the building.

21. The system of claim 20 , wherein the calculation of the inside irradiance comprises predicting the clear sky irradiance.

22. The system of claim 19 , wherein the calculation of the tint level uses feedback, wherein the feedback uses the measurements from the at least one sensor.

23. The system of claim 19 , wherein the calculation of the tint level uses a determination of whether the real-time irradiance values are less than the clear sky irradiance.

24. The system of claim 23 , wherein if the real-time irradiance values are less than the clear sky irradiance, then the tint level is made lighter.

25. The system of claim 23 , wherein if the real-time irradiance values are less than the clear sky irradiance, then the tint level is made lighter incrementally until the tint level is equal to or less than a threshold.

26. The system of claim 23 , wherein if the real-time irradiance values are not less than the clear sky irradiance, the tint level is made darker.

27. The system of claim 19 , wherein the network is further configured to transmit a dynamic determination of an effect of a surrounding environment to the building.