It may not seem like a big deal, but exploding manholes is an issue that US energy firm Con Edison knows all too well. In 2015, more than 3,781 manholes in America’s most populous city exploded, and while that number has been on a steady decline, it’s still a serious issue.
Thankfully, UK engineering and design consultancy, PlexTek, has been working with US-based CNIguard to develop a new IoT-based system to prevent manhole explosions. The solution has already been deployed in New York, but it could also see use in the UK, where more than 50 incidents a year of manhole explosions are reported to the UK Health and Safety Executive.
Manhole explosions are caused by a number of factors, including when a mixture of melting snow and road salt washes into the manholes, leading to the electricity cables arcing. This then causes the cables to catch fire, which when the pressure is too much for the manhole cover to contain, it simply explodes, potentially leading to serious injuries.
CNIguard’s new Sentir system – the first innovation of its type – works by monitoring gas, stray voltages, arcing, salinity, temperature and humidity with embedded IoT sensors underground and transmitting these signals to a dashboard on a smartphone, laptop or other device by radio, cellular, PSTN, fibre optic or satellite links. The system uses powerful cloud-based analytics to identify and predict conditions that may result in an incident so that preventative actions can be taken to avoid a potential disaster.
The Sentir system also helps to secure underground boxes, chambers, vaults, cabinets, kiosks and bunkers from intrusion, theft and vandalism with the help of visual and infra-red cameras, while providing flood warnings and other safety, environmental and quality monitoring.
“Plextek’s expertise in communication and sensor systems allowed us to accelerate our development and rapidly deploy Sentir into the market,” said Dr. Edward Klinger, CEO of CNIguard.
“Their work has enabled Sentir to include several different variations of environmental sensor with cellular capability powered by a reliable long-life battery or harvested power from underground cables themselves.
“Up until this technology was developed, these issues have been approached by utility companies and networks in a reactionary way, so little has been done to predict or prevent conditions which could cause explosions or stray voltage events.
“On top of this, global urban populations are set to rise, putting increased pressure on networks and this combined with environmental and climate factors will make these incidents even more common.”