Lightning strikes predicted with sensors

UN/DICYT “This equipment measures atmospheric variables such as environmental electric fields that when altered enable predicting presence of storms,” says UNal Department of Electric and Automatic Energy Professor Javier Gustavo Herrera. 

Environmental electric discharges or lightning are source of multiple deaths and damage to electric systems. Therefore different research projects seek to develop a system which can previously warn the occurrence of lightning strikes. 

Measuring environmental electric fields in storms is an old idea and there are devices that already perform this task; however the design carried out by UNal engineers is a local version of the idea and hence they can control every variable and have certainty of its operation. 

“This led us to learn several working stages of the sensor and the prototypes as well as the entire infrastructure needed to capture, process and store signals,” he said. 

The equipment 

The sensors known as field mills are comprised of a propeller on top of a metallic plate. The materials used are very economical and may be placed on top of any building. 

Storm clouds are loaded with electrostatic energy and part of this energy is captured by the sensor. When clouds grow, they also have greater electric load which is detected by the sensor 20 or 30 minutes in advance before lightning strikes. 

“In this manner we can predict if the cloud or storm forming will have the necessary size and intensity to threaten people in the area,” said Herrera. 

Valle de Aburrá measurements 

A year ago researchers entered into an agreement with the Medellín and Valle de Aburrá Early Alert System (SIATA, for its acronym in Spanish) which included providing additional information from the sensors.   

Therefore they installed three sensors in three buildings around the city with the purpose of measuring field variations and become cognizant of the likelihood of storms in these areas. 

Each station is independent and the information is processed locally and sent to a central server. Currently the sensors are still in a testing stage and being adjusted and calibrated. 

“We have performed measurements during the latest storms and observed the consistency and validity of the results. In the future we hope to have information on more points and provide greater information to the community,” he said. 

In Colombia and particularly in Medellín and its metropolitan area the particular conditions make it very prone to lightning activity, therefore the novelty of this project is to carry out measurements of this kind and provide information to the community to issue alerts.