Embodiments disclosed herein facilitates the monitoring of direct ultraviolet B (UVB) radiation exposure by a person via a system having a sensor (such as Lanthanum doped lead zirconate titanate (PLZT) thin-film sensors or other ferroelectric-based sensors) sensitive to UVB radiation. The system beneficially provides current real-time dosage information associated with Vitamin D production by the person as well as real-time indication of safe exposure and/or harmful exposure to current UVB radiation conditions while also, in some embodiments, takes into consideration a person's age, skin type and sensitivity, body surface area exposed.

In one respect, disclosed is a device or system for solar irradiance measurement comprising at least two irradiance sensors deployed outdoors at substantially different angles, such that, by analysis of readings from said irradiance sensors, direct irradiance, diffuse irradiance, and/or global irradiance are determined. In another respect, the disclosed device or system may additionally determine ground-reflected irradiance.

A system for monitoring ultraviolet (UV) exposure of a wearer. The system comprises a wearable device operable to sense UV radiation levels to which the wearer is exposed, and to transmit UV radiation information. The system further comprises an external computing device in remote communication with the wearable device, operable to receive the UV radiation information from the wearable device and configured to determine the wearer's real-time UV index value and the wearer's daily cumulative percentage of minimal erythema dose based upon the UV radiation information.

A method includes identifying a plurality of images corresponding to sky conditions and isolating cloud pixels from sky pixels in each of the plurality of images. Responsive to determining percentage of cloud pixels in one or more of the plurality of images meets a threshold value, the method further includes determining predicted cloud movement relative to sun position. The method further includes causing a tint level of an electrochromic device to be controlled based on the predicted cloud movement relative to the sun position.

An object of the present invention is to improve the accuracy of prediction in a technique for predicting natural energy power generation amount, solar radiation amount or wind speed by using a statistical method based on machine learning. In order to achieve this object, provided is a prediction apparatus (10) including a feature value extraction unit (13) that extracts a feature value being a variation in time series from meteorological data from m (m is 2 or more) hours before a target time to the target time, and an estimation unit (first estimation unit (14)) that estimates a natural energy power generation amount, a solar radiation amount, or a wind speed at the target time based on the feature values over plural days.

Systems and methods for pointing photovoltaic arrays for optimal power generation. One or more methods among a plurality of methods for pointing an array may be used by a spacecraft control system to point the array. Example methods to use to point the photovoltaic array relate to analyzing current output, analyzing image data, and analyzing computational knowledge of reflective bodies or light sources. The spacecraft may be further controlled to reduce shadow by re-orienting, receiving light reflected off spacecraft, and orienting a photovoltaic array relative to incoming light sources based on topographic properties of the array such as cell grooves.

A non-power-driven photometer is provided, the photometer comprising: a body; and multiple narrow angle photoreceivers (narrow angle probes) formed in the body, wherein the multiple narrow angle probes receive light in the atmosphere, which is incident over a range of different azimuth angles, and allow the characteristics of the atmosphere to be analyzed with reference to the relationship between the received light and the azimuth angle of the narrow angle probe corresponding to the received light. According to the present invention, since the photometer is driven without being supplied with power, light intensity measurement can be performed in a short time. Further, since light intensity measurement can be performed with no movement or only a short-distance movement of a vehicle or airplane equipped with the photometer, the problem of errors caused by differences in the time and location of measurement can be prevented.

A system and method for array level terrain based backtracking includes a tracker configured to collect solar irradiance and attached to a rotational mechanism for changing a plane of the tracker and a controller in communication with a rotational mechanism. The controller is programmed to determine a position of the sun at a first specific point in time, retrieve height information, execute a shadow model based on the retrieved height information and the position of the sun, determine a first angle for the tracker; collect an angle for each tracker in a plurality of trackers in an array; adjust the first angle based on executing the shadow model with the first angle and the plurality of angles associated with the plurality of trackers; transmit instructions to the rotational mechanism to change the plane of the tracker to the adjusted first angle.

The imaging assembly includes: a multi-band sensor (5), comprising a plurality of light sensors (7) each for measuring a light intensity returned by a target (8) in a predetermined frequency band; a sunlight detector (9), comprising a plurality of control sensors (11) each for measuring an ambient light intensity in one of the predetermined bands of frequencies of the multi-band sensor (5) each associated with a band-pass filtre; an electronic module (13) configured so as to calculate at least one characteristic variable value of the light intensity returned by the target (8) in each predetermined frequency band;
the sunlight detector (9) comprising a box casing (21), the control sensors (11) being attached to the box casing (21), the band-pass filtres (17) being attached to the box casing (21) each one so as to be facing the photosensitive surface of the associated control sensor.

A device and a method for detecting a light irradiating angle are disclosed. The device, used to detect the incident direction of a light ray, includes a solar sensor and a processor. The sensing unit of the solar sensor has sensing areas. The sensing areas correspondingly generate sensing signals based on the intensity of the light ray. A mask covers the sensing unit and has an X-shaped light transmitting portion. The light ray transmits the X-shaped light transmitting portion to form an X-axis light ray and a Y-axis light ray. The X-axis light ray intersects the Y-axis light ray. The X-axis light ray and the Y-axis light ray fall on the sensing area. The processor, coupled to the sensing unit, receives the sensing signals and determines information of the incident direction according to the sensing signals.