Dynamic Line Rating: A Solution to Grid Congestion

On a cloudy day in mid-July, a team of technicians wore a shiny metal orb, the size and weight of a child’s bowling ball, under a line of transmission of 110 kilovolts which flowed near Hamburg, Germany. Their task: attach the orb to the line where it will follow the environmental conditions in real time affecting the capacity of the wire.

To hoist the orb on the air line, a crew member attached him to a quadcopter drone and piloted it with a remote control. While he was approaching the thread, one side of the orb opened, like a real pac-man on the point of chompering a cheek of power, then tight. The process took approximately 10 seconds and required any electric stopping time.

Heimdall Power, based in OSLO, the manufacturer of the ORB, installed more than 200 on the transmission lines of SH-Netz, the operator of the grid in the northern part of Germany. Together, the devices form a system that calculates the current of these high -voltage lines which can transport safely depending on real -time weather conditions. The more hot it is, the lower their capacity.

Historically, grid operators have estimated the capacity of lines according to average seasonal temperatures – a fixed value called static line rating. For safety, estimates must be very conservative and assume that time is always very hot for the respective season. So for the hottest every day, the transmission lines could Transporting much more electricity, if the network operators only knew the actual temperature of the wires.

Tools like Heimdall’s Orb, nicknamed the “Neuron”, can fill this white. By following information such as the disc of the line and the ambient temperature, the system can more precisely determine the temperature – and therefore the capacity in real time – of the line. This allows grid operators to take advantage of the unused margin by maximizing the current in this line. The system uses weather forecasts to predict the temperature and capacity of lines for the next day, which is particularly useful for day planning.

The dynamic line rating offers a grid congestion solution

The strategy, called a dynamic line of lines, or DLR, is quickly adopted in North America and Europe as an antidote – at least in the short term – to the grid of congestion problems. New transmission lines are necessary to adapt to the explosion of AI data centers, electrification and renewable energy production, but building them is a notoriously long task often requiring a decade or more. In the meantime, grid operators must do more with existing infrastructure.

The dynamic line rating and other technologies improving the grid, or obtain, offer a quick and inexpensive solution – a bridge until a new transmission can be built. Heimdall is one of the many companies, including Linevision in Boston and Gridraven in Tallinn, Estonia, providing technology.

“Transmission operators do not maximize the potential of our power lines, which leads to unnecessarily high energy costs for consumers,” said Caitlin Marquis, managing director of Advanced Energy United, an industry defense group, in a press release. “Dynamic line ratings are one of the most profitable tools we have to make the most of our existing electrical network infrastructure.”

Heimdall Power’s orb is sagging, the ambient temperature, the intensity of the sun and other metrics on a transmission line in southwest Norway.Power Heimdall

Technologies improving the heimdall grid

In the approach of Heimdall, one of the key measures of its sensor track is the line line; As the metal wires become warmer, they develop and drop the line. Measuring sagging helps determine the decrease in capacity. The sensors also follow other information such as room temperature and the intensity of the sun. Heimdall combines information with local weather forecast data – in particular wind speed, which has a cooling effect on power lines and can thus increase their capacity.

Heimdall automatic learning uses data to help grid operators plan how they will transport electricity for the next day. In urgent situations, they can use real -time data from its sensors to adapt to the fly.

After working mainly with public services in Europe, last year, the company opened a headquarters in Charlotte, in North Carolina, to better access the American market. Its first major American project, in Minnesota, helps public service increase its capacity by 25% almost 70% of the time, according to public service. Heimdall has agreements with six additional American public services bringing its technology to 13 states.

“We have spent the last 80 years building the North American electricity network, and we always direct it as we did at first,” said Heimdall President Brito Formato. “DLR allows us to bring the existing grid to the digital age – mainly overnight and with a relatively low cost and efforts.”

Lidar sensors of Linevision improve monitoring of the electric line

Linevision, another dynamic line rating supplier, uses Lidar sensors to monitor line SAG and combines data with weather forecast and computer analysis of the way the wind is affected by objects near the power lines. Instead of putting its sensors directly on the power lines, the company sets them up on the towers. This facilitates installation and operation, according to Linevision.

The company originally used electromagnetic sensors to indirectly measure the load on each line, but swivel in Lidar because it has become cheaper and more widely deployed in autonomous cars. “When we made this change, we survived the wave of autonomous vehicles,” explains Jon Marmillo, co -founder of Linevision and business director.

The Lux sensor of Linevision uses the LIDAR to monitor SAG and is installed on transmission line towers.Linevision

For the prediction of the wind, Linevision begins with a detailed space card accessible to the public which includes buildings and trees, then uses automatic learning to interpret how obstructions change wind near the power lines. Marmillo says that it takes approximately 90 days of learning for the system to create precise predictions of line capacity after its installation. Public services then integrate this into their grid management software.

After completing a previous project with Linevision, National Grid, the grid opponent for England and Wales, announced in June a new larger project with the company, over 263 kilometers of 400 kV lines. The first project increased the capacity by 31% on average, releasing lines to transport an additional gigawatt of power and save customers £ 14 per year (US $ 19 million). The new project should allow customers to save £ 20 per year (US $ 27).

Gridraven’s wind forecast increases the dynamic line rating

In Estonia, the supplier DLR Gridraven takes on a different accent: it does not use equipment at all. Instead, it relies on automatic learning to make precise hyperlocal wind forecasts. The predictions are based on weather forecasts and a detailed satellite and Lidar field card.

Georg RuteThe CEO and co-founder worked for the national operator of the Estonia network in 2018 when he noticed that the wind forecasts around the electric lines were “really bad,” he said. Rute returned to study the question in 2023 with the other two co -founders of Gridraven, noting that two thirds of the error in the prediction of the wind were caused by the landscape – mainly buildings and trees.

The CEO of Gridraven, Georg Rute, founded the company after having realized that the prediction of the hyperlocal wind was not precise enough for the dynamic line rating.Gridraven

Gridraven began its first large deployment last month, covering 700 km of 400 kV lines from Finland, and plans to develop in the total network of 5,500 km from the country of high -voltage transmission lines. “With DLR, it is particularly possible to support the integration of wind energy into the network,” said Arto Pahkin, director of Fingrid, the operator of the Finland transmission system. “This makes the DLR a strategically important part of the integration of renewable energies.” The Gridraven system can increase the capacity of power lines by 30% on average, according to the company.

DLR companies do not emphasize that technology is not a remedy for everything that makes our grids; In the long term, we will simply need more transmission. Congestion already increases electricity prices and increases breakdowns. Since 2021, congestion of the network has cost American consumers from $ 12 to 21 billion a year, according to electricity prices and weather.

Other technologies improving the grid can help in the meantime. For example, the renewal of existing lines with advanced materials can double their capacity. But this approach also makes lines out of use while the new materials are installed, and it is more expensive than the DLR.

“The potential of the DLR is to unlock up to a third party in the existing grid in the world,” said Rute. “This would increase economic growth and immediately increase affordability while more grid is under construction.”