How smart vision system minimizes power consumption of roof-top ice melt cables.

AI cameras

Ice dams on the roof can cause heavy damage to buildings in snowy regions. Heat cables prevent them, but waste Terawatts of power when used permanently. Maxlab developed an innovative camera module that monitors the snow and ice level on the roof to melt it only when necessary – saving up to 90% energy and reducing CO₂ emissions accordingly.

In regions with a rough winter climate, heavy snow, and ice layers accumulated on roofs can cause substantial damage to buildings. The nightmare of many homeowners and facility managers is the so-called ice dam. The accumulation of ice at the edge of a roof not only causes icicles but also creates a dam that prevents water from properly flowing down the drain when the softer snow layers melt. The trapped water flushes back up beneath the shingles and enters the attic, causing unhealthy mold, costly damage, and potential electrical safety hazards.

90% wasted energy

To avoid that, North American roofs in snowy regions are often equipped with so-called heat cables. These electric heating cables laid on the edge of the roof melt the snow and ice to prevent the formation of a dam. While this is an efficient solution to protect the property, it is extremely inefficient from an energy consumption perspective, because it blindly operates regardless of the snow and ice level. The heat cables could be switched off 90% of the time, but they are not. Building owners waste large amounts of money on their power bills, and the wasted energy is an unnecessary burden on the environment and the climate. Thermometer-based systems attempt to reduce waste but can only make assumptions based on the weather conditions. They don’t accurately assess the actual ice formations on the roof.

A US-American company teamed up with Maxlab, a Canada-based computer vision solution provider, to design a solution to that issue using image processing technology. The system consists of one or several camera modules (depending on the size of the roof) that monitor the level of snow and ice on the edge of the roof and trigger the heat cables only when necessary. The camera uploads the captured image data to the cloud via a smart hub for processing. The software not only recognizes the formation of an ice dam but also compiles the data with weather data to optimize the operation of the heat cables even further. If necessary, the heat cables are switched on but remain switched off most of the time when not needed.

Custom development for tough operating conditions

“The camera module developed had to fulfill demanding requirements to operate under such tough conditions”, explains Constantin Malynin, co-founder of Maxlab. Each module consists of two full-HD cameras to provide a panoramic view of the roof. The image sensors are infrared-sensitive to operate under low-light conditions during long winter nights and when the camera itself is covered with snow.

Like the heat cables, the camera module is permanently installed on the roof. That means that it must withstand both the low temperatures of the winter and the summer heat. The module is designed to operate in a temperature range from -40°C to +80°C (-40°F to +176°F).

The housing is UV-resistant and IP68 waterproof to withstand weather conditions. It is also designed to withstand the weight of a person mistakenly stepping on it during installation and maintenance. 

Another specificity of Maxlab’s camera module is its extremely low power consumption. To simplify installation on the roof, the camera is not connected to a power supply. It runs on a battery that works in tandem with a solar panel. Since the whole module will typically be covered with snow for weeks, one battery load ensures the system is self-sufficient for the whole winter. 
Maxlab not only developed the camera module but also the hub that connects the system to the cloud. 

Fast development with robust embedded vision technology

The development of the camera module was completed within nine months between the first sketch and the first manufacturing batch. This was made possible by Maxlab’s unique Tokay camera platform. Tokay is a modular embedded vision platform designed and validated by Maxlab that allows Maxlab’s engineers to develop custom solutions from pre-existing building blocks. “This modular platform approach is the key to Maxlab’s ability to deliver reliable solutions such as the rooftop camera within a short time frame”, explains Constantine Malynin. 

Maxlab supervised the manufacturing ramp-up during the first year before handing it over to their client. The system has now been selling in thousands of homes and facilities across the United States. Maxlab’s client estimates that thanks to this solution, heat cables can be safely turned out more than 90% of the time, saving $100-$400 energy costs per month to the owner depending on the size of the property. The system also provides relief to the power network in times it is needed most. Finally, it saves an estimated 500-1,000 kg CO₂ (1,000-2,000 lbs) per month for an average American home.
“This application is a perfect example of how vision technology can make a difference for a better planet by delivering a solution in which everybody wins: homeowner protect their property and save money, the power networks are offloaded in peak times, and the system protects the environment by reducing CO₂ emissions. We are proud to contribute to such projects and we are convinced that vision is part of the answer to many environmental problems ahead”, says Constantin Malynin.