Novel Static Sensor Array for Diffuse Irradiance Measurement

We report on an updated field trial to test measurement of diffuse horizontal irradiance (DHI) using a novel low-cost combination of static sensors with no moving parts. The system pairs two tilted reference cells, one of which measures global irradiance and the other of which is modified with an isolator tube that admits only diffuse light contributions from a limited region of the sky. Using reference data from a research-grade tracking diffusometer, we trained a neural network model to use the readings of the two static sensors to estimate DHI. In this work, we have updated our field testing to include almost 1 year of data from the test site. A second test site at different latitude was recently installed and will be used for additional validation in subsequent work.