Rooftop heat cables guard against the perilous effects of ice and snow accumulation. These strategically installed heat cables become hot when an electric current runs through them, and the radiated heat melts snow and ice to allow proper drainage. However, protecting roofs in this way incurs monetary and energy costs.
Heat cables strategically installed on roofs prevent damaging ice and snow accumulation. Image courtesy of Powder Watts.
Powder Watts has developed a patented IoT ecosystem to keep snow and ice from damaging roofs while slashing the cost of powering heat cables. The ecosystem includes a smart rooftop IoT sensor unit, power-switching devices to control and monitor heat cables, and AI to determine the presence of snow and ice. Left unchecked, heavy snowfall on a roof can cause ice dams along the roof’s bottom edge. When that happens, melted snow on the roof’s surface travels backward under shingles and into a structure. The resulting damage can equal tens of thousands of dollars or more for building owners.
According to Powder Watts, sometimes homeowners in snowy climates ask electricians to install thermostats to heat cables to attempt to curtail energy use when temperatures climb above 50° F. Many electricians tend to avoid these jobs because if a thermostat fails or is warmed by sunlight, it can falsely detect warmer weather, shut off heat cables, and allow an ice dam to form.
Thermostats are problematic for another reason. In northern regions, the air temperature from November to March rarely exceeds 50° F. Despite sub-freezing temperatures, when used correctly, heat cables can effectively clear channels through the snow along a roof’s edge, meaning a homeowner could temporarily shut off the cables and save power. The challenge is knowing when heat cables have successfully melted drainage channels and when homeowners need to power the cables.
“Electricians, if they even install a thermostat for your heat cables, often set them to turn off the cables when the air temp reaches 50° F or even higher because they don’t want callbacks,” said Thomas Clardy, founder and CEO of Powder Watts. “At 50°, the cables can draw energy into May.”
Clardy and Powder Watts wanted to build and sell technology to eliminate the nearly always-on approach of thermostats and the guesswork by switch-flipping owners. According to Clardy, a smart system relying on IoT technology must employ protocols to communicate data effectively. But the Powder Watts team didn’t like the real-world performance of existing home and business automation protocols.
A smarter approach to snow removal
Powder Watts’ solution includes a smart rooftop sensor and AI to monitor heat cables. With its expertise in embedded and networking technology, Grid Connect’s engineers helped Powder Watts develop a smart switch to enable the system to power on and off heat cables based on the conditions that the rooftop smart sensor and AI were interpreting, including the amount of ice and snow and weather conditions, such as humidity and temperature. To do this, Grid Connect’s engineers assisted in developing a 30 A, 240 V switch to Powder Watts’ specifications that building owners could control with the Powder Watts mobile app.
The smart camera, protected by a UV-resistant enclosure, is part of a system that sees inside rooftop mounds of snow to accurately determine when heat cables need to be on or off. The dual-camera system provides panoramic views of a roof and integrated night vision. Image courtesy of Powder Watts.
Grid Connect also manufactured a version of their 20 A Smart In-Wall Outlet to Powder Watts’ specifications. This allows for energy monitoring and independent socket switching, giving homeowners precise and individual segment control of their new or existing 120 V heating cables.
Grid Connect made a version of its 20 A Smart In-Wall Outlet for energy monitoring and independent socket switching, giving homeowners control of their 120 V heating cables. Image courtesy of Powder Watts.
The IoT system consists of five elements: a rooftop smart sensor; a smart hub receiving and sending signals; a smart switch measuring energy and turning on and off the power to the heat cables; AI to evaluate conditions and make switching decisions; and the Powder Watts App to enable full customer insight and control. Each element communicates with the other using a long-range protocol. According to Clardy, LoRaWAN didn’t have the throughput to handle the HD images taken by the rooftop smart sensor.
“Nobody made a long-range high-amp smart switch capable of monitoring energy,” said Clardy. “We didn’t want to run our system on WiFi, so Grid Connect incorporated our long-range protocol leading to outstanding performance.”
Inside the smart camera is a 30 A, 240 V switch measuring energy and turning on and off the power to the heat cables. Image courtesy of Powder Watts.
Ultimately, Grid Connect helped Powder Watts bring a robust, commercially available IoT switch to market. The Powder Watts system stands up to not only -40° F but also extreme summer heat and severe hail. As for savings opportunities, Clardy said there are approximately 44 million runs of heat cable across the United States. The owners of such heat cables spend hundreds of dollars monthly more than necessary to protect their roofs. Powder Watts’ smart technology typically provides a return on investment in 12 to 24 months.
“This is enhanced further by power company rebates and tax incentives. Compare that with solar payback times and for similar amounts of energy. If you own a home or business and you’re spending $200 or more per month to power your heat cables, Powder Watts can reduce that by up to 90%,” said Clardy. “It’s exciting to see American engineers creatively solve complex challenges in short timeframes.”
Smartly switching these high-draw heat cables on and off also plays a role in shedding unneeded electric loads off the grid. The cumulative effect of millions of miles of heat cables running across hundreds of thousands of homes for months on end means wasted energy and unnecessary grid drain. Powder Watts aims to work with a variety of utilities that want to manage these loads effectively and safely while keeping energy costs in check.”
“We help companies and homeowners meet their monitoring goals for safety and their energy goals for climate and cost,” said Clardy. “Why rely on 1970s thermostat technology or an owner’s watchful eye?”
This season Powder Watts is expanding their energy-saving technology into the heated driveway, walkway, and steps market. These heated surfaces provide great convenience and safety for people but come at great energy expenditure. As with heat cables, using smart sensing technology combined with AI can direct the heating only when needed, resulting in savings for customers and the planet.
Powder Watts
powderwatts.com
Grid Connect
gridconnect.com
Filed Under: IoT • IIoT • Internet of things • Industry 4.0, AI • machine learning, Sensors (temperature)
