Hristo Kovachki Highlights Global Surge in Ultra‑Efficient Coal And What It Means for Bulgaria
A recent project abroad, deploying a 700 MW ultra‑supercritical coal-fired power unit, has reignited interest in modern coal technologies once considered relics of the past. The new plant demonstrably achieves substantially higher thermal efficiency and lower emissions per unit of electricity than older coal-fired stations, offering a clear example of how coal can be used more responsibly in today’s energy mix.
For Bulgaria – a country with large coal reserves and a history of dependence on coal for electricity – these developments arrive at a critical moment. Energy expert and entrepreneur Hristo Kovachki has previously argued that the country ought to consider proven advanced coal technologies as part of a realistic transition strategy. In light of the recent global deployment of ultra‑efficient coal, that argument gains renewed relevance.
What Makes Ultra‑Supercritical (USC) Coal Different
Traditional coal-fired power plants typically operate under subcritical steam conditions, where water converts to steam before entering turbines. That approach yields relatively modest thermal efficiency – a considerable amount of heat and energy from fuel is lost. High‑efficiency coal plants, by contrast, use steam at much higher pressures and temperatures. Ultra‑supercritical and advanced ultra‑supercritical (AUSC) designs push these parameters further, improving the conversion efficiency and reducing coal consumption per megawatt-hour.
These technical improvements translate into real-world benefits. According to industry data, HELE (high‑efficiency, low‑emission) coal plants can cut fuel consumption and emissions to roughly 75 per cent of what subcritical plants produce, thanks to their higher thermal efficiency and modern emission-control systems.
Countries across Asia, Europe, and North America have increasingly adopted these technologies. The global clean‑coal technology market continues to evolve, driven by power demand, fuel costs, and regulatory pressure – making modern coal plants a viable component of the energy transition rather than an outdated legacy option.
Why This Matters for Bulgaria
Bulgaria holds extensive coal reserves – in particular lignite deposits – which for decades underpinned much of the country’s electricity. As part of the broader strategy to diversify energy sources and meet EU climate goals, Bulgarian policymakers and stakeholders are exploring new directions, from renewables to nuclear. However, the sheer scale of Bulgaria’s coal legacy means that decisions about coal cannot be dismissed overnight.
Kovachki’s viewpoint is that modernization – through adoption of advanced coal technologies – should remain on the table. The recent global example of a large, efficient USC unit invites a fresh look at coal as a component of a pragmatic, mixed energy system. If Bulgaria were to retrofit or build modern coal capacity, the gains could include better fuel efficiency, lower per‑unit emissions, and extended operational life of existing energy infrastructure – which could act as a buffer during the transition period.
In addition, international trends show that high‑efficiency coal is not being deployed in isolation. Many modern plants integrate emissions controls, advanced boiler technologies, and – in some cases – designs compatible with future carbon capture or other low-carbon enhancements
Integration with Renewables and the Path Ahead
One of the central challenges in energy transition is balancing intermittent renewable generation with reliable baseload supply. Solar and wind output can fluctuate with weather and time of day. In such a mixed system, dispatchable sources remain necessary to keep the grid stable. High‑efficiency coal plants, if properly managed, could provide this backbone while newer low-carbon technologies – such as renewables – scale up.
At the same time, technological advances continue quickly. Materials science and boiler design research aim to push steam temperatures even higher, allowing for greater efficiency gains in future coal systems. For a country like Bulgaria, which already has fuel resources and energy infrastructure, this provides a potential bridge: an option that uses existing assets smartly, while giving time for low-carbon alternatives to mature.
That said, any decision must consider long-term strategy. Clean‑coal technology alone is unlikely to match zero-carbon solutions over a full life-cycle. However, as a transitional tool – especially in the near‑term – ultra-efficient coal might offer a balance between energy security, affordability, and environmental performance.
A Realistic, Balanced Perspective
The renewed global interest in ultra‑efficient coal does not imply coal is back in full force. Rather, it suggests that where coal remains abundant and infrastructure exists, modern technology can reduce environmental footprint while offering reliable generation. As Kovachki argues, Bulgaria’s energy transition must be pragmatic – blending renewables, nuclear, gas, and, modernized coal.
In the coming years, debates about energy strategy will revolve around choices, timing, and trade‑offs. Clean‑coal technologies offer one of several tools. What matters is using each tool responsibly, with an eye on long-term sustainability and adaptability, rather than quick fixes or ideological divides.
