Keeping it cool: Why we need cooling systems to keep electricity flowing

Just as our bodies need a precise temperature range to function optimally, so do the complex machines that underpin modern society. Consider a smartphone, a device that has become an essential tool in our daily lives. When it overheats, its performance degrades and may even shutdown. Similarly, the vast infrastructure of data centers and power plants that power our digital age and industries requires precise temperature control to operate efficiently and reliably.

From the smallest electronic components to the largest industrial facilities, electrical currents generate heat, making heat management crucial for uninterrupted energy flow.

By understanding the intricacies of thermal management and implementing innovative cooling technologies, we can ensure the continued operation of our critical infrastructure and maintain the delicate balance between technological advancement and environmental sustainability.

The hot issue

Starting small, charging your phone uses energy and generates heat as it powers up the battery. And we want to charge our phones fast, sometimes so much so that the phone overheats. When this happens, you naturally find ways to cool it down, such as unplugging it temporarily. Failing to do so can damage its battery, force a shutdown, or cause a complete breakdown.

The same logic follows bigger, more complex processes like charging an Electric Vehicle (EV). Because a larger apparatus entails a bigger charging station and a chunkier cable, more energy flows faster. This also means you build up more heat in a cable that needs serious and professional cooling. 

Similarly, operating machinery can be affected by excessive heat. For instance, converters in various industrial sectors, such as railways and mining operations, can overheat due to the conversion of electrical energy from one form to another. During hydrolysis - the process of extracting hydrogen from water – heat risks the machinery's efficiency and safety. The implications become even more significant when scaling up equipment while maintaining a compact and efficient design, as is the case with large-scale electrical systems like the power grid. 

The electrical grid comprises several sophisticated pieces of equipment that perform large and complex tasks 24 hours a day, seven days a week. Among these components, the High Voltage Direct Current (HVDC) systems play a key role in moving large amounts of electricity over long distances with minimized energy loss. HVDC transmits electricity from distant power sources to substations, where it is further distributed to your homes, allowing you to power the device you're reading this blog on. It's a strategic and vital part of the grid connection that requires utmost attention and cooling to ensure its reliability and longevity.

Significant heat generation becomes inevitable with the escalating amount of power that HVDC links are dedicated to transferring. Excessive heating risks the equipment's materials, performance, lifespan, and safety. In extreme cases, overheating can cause a domino of failures that could eventually lead to large-scale outages and environmental damage.

Considering these challenges, it becomes essential to equip products with preventive measures that effectively control the temperatures and ensure the seamless and efficient operation of our grids.

The cool solution

Just as people use air conditioning units or water to cool down when they feel hot, the electrical grid also relies on cooling systems to maintain optimal operating temperatures. These cooling systems can be oil-, air-, or water-based and help mitigate the risks of excessive heat.

Cooling systems aim to: 

• Extend the lifetime of equipment – Persistent overheating can accelerate the wear and tear on vital substation components, leading to more frequent maintenance, repairs, outages, and ultimately higher costs.

• Avoid equipment damage – Degradation of materials may occur because of uncontrolled high temperatures, resulting in electrical failures and short circuits.

• Avert safety risks – Fire hazards, oil leaks, and explosions due to overheating and degradation can negatively impact not only the station but also the surrounding environment and personnel if not adequately contained.

• Reduce load loss and inefficiency – Insufficient cooling of a load can cause voltage instability, leading to poor power quality and potential outages.

Hitachi Energy is a leading player in cooling power transmission and industrial processes. Our factory in Landskrona, Sweden, stands as a testament to our 40 years of experience with this technology. 

^{Founded in 1980, Hitachi Energy's cooling systems factory in Landskrona, Sweden specializes in cooling systems and produced the first water cooling unit.}

Hitachi Energy's solution for high energy efficiency offers optimized operational performance, flawless quality and reliability, proven technology, and custom solutions for different voltage levels and dimensions. Currently, we provide cooling capacities ranging from 2 kilowatts to several megawatts and use a variety of coolants. Our most commonly used cooling media is water, with its quality determined by the specific application.

Pure, de-ionized water is employed when applications demand a medium with exceptional electrical insulating properties. These applications include metallurgic processes, food and medical industry operations, magnetic coils, and semiconductors in electronic devices (e.g., HVDC, switched virtual circuits, converters, etc.). Conversely, tap water is suitable for cases where dielectric properties are not critical and the primary function is heat removal, such as cooling rooms and energy storage systems. Glycol/water mixtures are utilized in environments prone to freezing temperatures to prevent ice formation and ensure uninterrupted operation. Lastly, oil can be used for specific applications such as EV charging cables, enabling a compact and lighter cable design with effective heat dissipation and the ability to handle higher currents, thanks to its excellent thermal conductivity. 

Our cooling systems provide engineered solutions tailored to specific applications and customer needs. They are also prefabricated, meaning the components are assembled, tested, and verified before delivery to ensure compliance with design specifications and efficient on-site installation. 

Beat the heat: the future is cool

It is no surprise that the world is getting warmer and warmer due to the climate crisis. In fact, the planet experienced its warmest day in recent history just last year¹. Therefore, taking cool and concrete steps toward a sustainable future for all is crucial.

Technological advancements are driving the transition to sustainable energy solutions as the world grapples with global warming. The increasing adoption of EVs and the deployment of powerful HVDC systems to integrate renewable energy sources into the grid are at the forefront of this shift.

Recognizing the critical role of cooling in enabling these technologies, Hitachi Energy develops innovative cooling solutions that ensure optimal operating conditions and temperatures for equipment worldwide. By maintaining ideal thermal profiles, these solutions contribute to the reliability, efficiency, and longevity of essential infrastructures, supporting the global transition to a sustainable energy future. 

¹ NASA Data Shows July 22 Was Earth’s Hottest Day on Record