But electricity does not become useful on its own. Between a solar plant or battery system and a heat pump or server stands an often-invisible layer of technology – power electronics. It controls how electricity is used in power grids, as well as in everyday devices like laptops and smartphones.

That is why power electronics deserves more public attention. It connects renewable energy to the grid, allows batteries to charge and discharge safely, keeps industrial processes stable. Because wind and solar are variable by nature, power electronics is what turns them into practical energy sources by integrating generation and storage into one coordinated system. Yet sustainability is only half of the story. The other half is resilience. A modern society relies on critical infrastructure that cannot function if electricity disappears for hours or days. Water systems, telecommunications, transport hubs, or emergency response centres all depend on continuity of supply. In such systems, stable electricity supply is a condition for safe functioning.

Resilience is not only about stronger power lines or larger substations. It is also about making sure that critical loads can keep operating when the energy system is damaged.

Power electronics cannot prevent every failure in the wider grid. Instead, it provides resilience where electricity is actually used. Power converters can connect batteries, mobile generators, renewable sources and other local backups to critical equipment, and regulate energy sources smoothly. That allows critical systems to keep operating even when the surrounding power system is unavailable. At the same time, resilience today is no longer only a question of physical damage. As power electronics systems become more intelligent and more connected, they also become more exposed to cyber threats. A failure may come not only from a storm or missile strike, but also from malicious interference. This means that modern resilience must combine electrical robustness with cybersecurity. In the coming years, secure and resilient power electronics will be essential not only for energy transition, but also for national security.

This is highly relevant for Estonia. If a country preparing seriously for crisis, disruption or war, it cannot think only in terms of fuel reserves, shelters or backup generators. It must also ensure that critical infrastructure can be supplied locally and securely when the wider power system is under stress. Power electronics is therefore becoming part of preparedness by providing reliable emergency supply for the services that matter most.

TalTech is investigating these questions through the international IMPRESS-U project, where researchers from the United States, Ukraine, Poland, Lithuania and Estonia are developing new approaches to reinforce critical infrastructure. For Ukraine, this work has immediate practical meaning. Recent years have shown how vulnerable energy, communications and public services become when infrastructure experiences repeated shocks. In such conditions, recovery is not only about replacing damaged equipment, but about designing systems that can absorb shocks, adapt and restart faster. TalTech develops resilient power electronic technologies for such situations.

In a critical infrastructure that suddenly loses connection to the grid, these systems can connect batteries, local renewable generation or mobile generators and turn them into stable electricity for critical loads. They can prioritise the most important equipment. In disaster relief, and even more so in wartime, such resilience can make a real difference. Also, technologies developed for Ukraine can also help strengthen resilience in Estonia. The threats are not identical, but the underlying challenge is similar. Solutions designed for repeated shocks, rapid recovery and flexible use of local energy resources are relevant for both countries. In that sense, IMPRESS-U is not only support for Ukraine, but also provides an important knowledge for Estonia’s own civil protection and defence preparedness.

Moreover, power electronics has become a critical element in the most demanding scientific environments in the world, such as CERN. Particle accelerators may seem far removed from disaster relief, yet they depend on the same principle – electricity must be delivered with extraordinary precision and reliability. The Large Hadron Collider already uses more than 5,000 power converters to operate magnets and radiofrequency systems that guide and accelerate particle beams. The proposed Future Circular Collider would raise that challenge even further.

At TalTech, we are developing novel power delivery architectures for such applications in the TEM-TA23 project. The aim is to reduce losses, shrink size and improve efficiency. This work also matters for Estonia’s economy. CERN is not only a place of scientific prestige, but also a marketplace for high-value engineering. Estonian companies such as Harju Elekter and TET ESTEL have already shown that local industry can compete there successfully. Future advances in power electronics could strengthen this position further, opening new business opportunities.

It is important to underline that power electronics is not a niche topic hidden inside university laboratories. It is one of the enabling technologies of the 21st century. It makes electrification possible, makes renewable energy practical, increases efficiency and strengthens the resilience of the systems society depends on every day. When electricity must be available without interruption, power electronics becomes indispensable. By advancing converter technologies, cybersecurity-aware control and resilient power architectures, TalTech is contributing not only to academic knowledge, but to a safer and more capable society.