‘Smart water meters’ cut usage

A CASE study of three Boland schools’ water consumption has shown that they each used daily what two households consumed.

Conducted by Stellenbosch University, the information prompted Professor Thinus Booysen and his team from the electrical and electronic engineering department to create “smart water meters”, which sends water readings to the principals’ cellphones.

Shortly after a pilot project at Stellenbosch Primary School a few months ago, their water consumption dropped from 35kl a day to 11kl.

The amount of money they saved equated to the salaries of two junior teachers. Deputy principal at the school, Jacques Horn, was impressed.

“We have already saved a lot of water and everyone is more aware of saving water. We have even adjusted the water supply to the bathrooms.”

A burst pipe at the school during the July holiday immediately triggered an alarm and the school was able to react.

Dirk Coetsee, of Eikestad Primary School, said after the installation of the water-meter reader, the school managed to save at least 3kl of water a day.

“We picked up there was water use over weekends when there was no one at school. Then we discovered a water leakage underground.”

The device, attached to the municipal water meter, reports into a web server via cellular, NB-IoT or Sigfox networks.

In layman’s terms, the reader sends water usage information to cellphones.

“We wanted to make schools and the pupils aware of how much water they were using. We designed the devices to allow for principals, deputies and a project champion at the schools to be able to monitor the usage,” Booysen said.

He said five schools would put the technology to the test by the end of August.

Their case study showed that schools were spending up to R40 000 a month on their water bills, the biggest guzzler being toilets, Booysen said.

His team has also connected timers to the water supply. This has meant water to the restrooms could be closed in the late afternoon and opened again the following morning.

“Every drop counts, not only when it comes to preventing water wastage, but also saving the bank account from drying up. This is especially true for schools with already constrained resources and with limited tools available to affect savings. Through the use of smart metering technology, they have enabled schools, households and other institutions to limit water usage and to minimise expenses,” the university said.