Electrical utility networks generate, transmit, and distribute the electrical power that keeps our homes, workplaces, businesses, and transit systems running smoothly. They are also essential in the global movement towards utilizing more sustainable energy sources and reducing our reliance on fossil fuels.
These systems consist of numerous component parts, all of which require careful maintenance and management to keep them in good working order and to keep power flowing to where it is needed.
A critical aspect of keeping electrical utility networks functioning well is keeping the systems cool. When electricity is transmitted through a cable, it generates heat. If these high temperatures are not properly managed, they can decrease performance, damage equipment and infrastructure, increase the risk of power outages, and even become a fire hazard.
At MAC, we supply various cooling plants and cable cooling systems to the electrical utilities industry. In this post, we will explain how cable cooling mechanisms and processes work, discuss the environmental challenges and benefits they present, and explore the future of these technologies.
How Does Cable Cooling Work?
Once certain temperatures are reached, conductors' ampacity, or the amount of current that they can safely and effectively carry, is limited. Keeping the cables and conductors cooler and implementing systems to reduce temperatures or dissipate thermal energy effectively enhances the ampacity and allows power to flow more efficiently, reliably, and safely, ensuring a stable power supply.
MAC provides equipment designed to cool the dielectric pipe-type cable underground transmission systems. Cooling this liquid ultimately cools the copper conductor at the center of the cables, protecting it from the damage that high temperatures can cause. The primary purpose of cooling the dielectric fluid in a cable system is to increase ampacity.
The Main Types of Cable Cooling Systems and Cable Cooling Plants for Electric Utilities
There are three main types of cable cooling systems, each suitable for different applications, environments, and conditions.
The first type is an oscillation or slow-circulation cooling system. In these systems, an oscillating mechanism shuttles the liquid slowly back and forth. Slow circulation cooling is most often used for the thermal smoothing of a cable system, focusing on hotspots and areas where more heat is transferred out of the cables. This process typically yields a 1-2% ampacity increase.
The second type is a high-speed circulation cooling system. Here, special pumps move the liquid from one point to another and then back at a rate of 25 gallons to 200 gallons per minute. Sometimes even higher flow rates are designed for a cooling plant..
When a high-speed circulation cooling system is combined with an air heat exchanger, the cables' overall ampacity increase can be as high as 7-9%. The exact increase depends on various factors, such as the unit's geographical location; using ambient air is more efficient in colder, drier climates than in hotter regions with high humidity.
The third and final type of cable cooling mechanism is the refrigeration cooling plant. These cooling plants cycle the liquid through a refrigeration unit and multiple heat transfer devices to dramatically reduce its temperature.
Electrical utilities companies decide which type of cable cooling system to use based on various factors, including need, cost, and environmental considerations. If the power demand is increasing, adding a heat exchanger or slow circulation cooler will add ampacity without needing to replace cables or add new cables.
Refrigeration cooling plants are generally reserved for extreme cases where the cable network is under significant strain. This is because refrigeration units cost more than other options and have the highest upkeep requirements. For example, their compressors and intermediary transfer elements need to be maintained and replaced regularly.
Compared to refrigeration cooling plants, low- and high-speed circulation coolers with air heat exchangers are both low-maintenance options.
What Are the Environmental Challenges and Benefits of Cable Cooling?
Cable cooling processes and cooling plants play a vital role in addressing sustainability challenges, hastening the movement towards renewable energy, and preserving the environment by extending the life and enhancing the performance of electrical utility networks and their components.
They also reduce the thermal stress placed on cables, reducing the risk that high temperatures will ultimately cause those cables to break down.
Additionally, cable cooling facilitates more efficient and reliable delivery, control, and management of electrical power, ultimately making the entire network more efficient.
Adding cooling plants instead of new transmission circuits to a power network is usually a more sustainable option. This avoids both the disruption and the environmental impact of building new infrastructure.
The various types of cable cooling mechanisms also present sustainability challenges and benefits.
Air heat exchangers are the most sustainable option overall. This is because they use ambient air, which is pulled through a sealed system. No harmful emissions are released into the air..
Refrigeration units have more of an impact on the environment, though modern versions are becoming more eco-friendly than their older counterparts.
The Future of Cable Cooling: Effectively Dissipate Heat with The Latest Innovative and Sustainable Solutions
Many cable cooling solutions, such as air heat exchangers and liquid circulation systems, are well-tested mature technologies that have been used for decades and will likely continue to be used for many years.
However, advances in materials technology may assist with better thermal transfer processes in future iterations of these technologies.
We may see further advances in refrigeration plants in the coming years. Advances in refrigeration systems' capabilities will make these plants smaller and more efficient and allow for the utilization of more environmentally friendly technologies.
Here at MAC Products, we make and supply all three types of cable cooling systems discussed in this post.
We have incorporated slow and rapid circulation into pumping plant equipment, as well as designed and manufactured stand-alone units with air heat exchangers and refrigeration cooling plants.
Our motto is "We don't do easy," meaning we never shy away from a challenge. Our customers include utilities companies throughout North America, and we are proud to design and create bespoke solutions to solve any problems our clients encounter.
To learn more about our cable cooling and cable temperature control solutions or to inquire about any of our products or services, please fill out our contact form or give us a call. A member of the team will be happy to help you.
