HomeFeature ArticlesInternal combustion engines go for hydrogen readiness

Internal combustion engines go for hydrogen readiness

There are engines already being successfully powered by hydrogen today, but when will engines generally be ready for hydrogen? CIMAC Secretary-General Peter Müller-Baum offers his insight.

Why should we prefer to run engines on hydrogen and its derivates in the future?

The answer is simple and, at the same time, terrifying. The earth has become warmer and warmer than in the past: The average temperature of the last three decades has always been higher than that of all other decades since records began in 1850. This is alarming, and the negative consequences of global warming can already be felt almost everywhere.

Climate protection is hence the central challenge of our time. It is essential to counteract global warming and its consequences now. The focus is on rapidly reducing emissions of greenhouse gases such as carbon dioxide (CO2).

CO2 is released, among others, when fossil fuels such as coal, oil, gas or their derivatives are burned: in industry, in transportation and traffic, for heating and cooling or for power generation. To drastically reduce greenhouse gas emissions, various solutions can and must be pursued.

Renewable energy sources, especially solar and wind energy, will play an increasingly important role in the future. With their help, electricity can be generated.

But regenerative energy sources do not always actually supply energy. For example, when it is dark and there is no wind. Thus, to ensure security of supply, alternatives must be available that do fill the gaps.

This is where internal combustion engines come into play. They can be started quickly and therefore react flexibly to the fluctuating electricity yield from renewables. The combustion engine has proven its robustness and reliability over decades and does not produce any CO2 emissions during the utilization phase itself – it is the traditional fossil fuels that are responsible for CO2 emissions during the use phase.

And this is where renewable energy sources come into play again. There is another reason why they are so important: ‘Green’ hydrogen can be produced by electrolysis of water with electricity from these renewable sources.

Today there is no doubt about green hydrogen being the heart of the energy system of the future because it is CO2-free. It can either be used directly or converted further; for example into eFuels, synthetic fuels that can already power combustion engines in a climate-neutral way.

Thanks to Power-to-X (or P2X, PtX), green electricity in the form of chemical energy carriers can be stored efficiently and for a long time.

In many countries – such as China, Japan, and Korea, but also in France and Germany – governments have long since set the course for future hydrogen use. There is also an ambitious hydrogen strategy at EU level. The hydrogen economy in the US is also likely to grow rapidly, especially now that it appears to have political support. And the US has extensive, low-cost solar and wind energy resources, and plenty of space. For emerging economies that have few energy systems and are just building them, hydrogen will also be important.

The World Energy Council predicts that in the future hydrogen will come primarily from countries such as Saudi Arabia, Chile, or Australia – from regions where wind or sun, and thus potentially renewable energy, are abundant. Countries like Germany, however, will continue to import energy in the future because they consume more energy than they can generate themselves from renewable sources.

The question of transportation has not been conclusively resolved since hydrogen as a gas is best transported by pipeline. For regions like Patagonia for instance, one must also consider conversion steps from hydrogen to, for example, ammonia or hydrocarbons. This is one more good reason to consider the use of eFuels as well. In any case, innovative technologies based on hydrogen offer enormous potential everywhere to successfully defossilize industries.

There are engines already being successfully powered by hydrogen today, but when will engines generally be ready for hydrogen? After all, stationary internal combustion engines are very longlived assets that require high levels of investment from their operators.

Those engines that go into operation today or in the near future will most probably still be powered by conventional fossil fuels. But they must be adaptable to the requirements of a climate-friendly energy supply. This creates investment security and thus a willingness to invest. Moreover, this future security is an important contribution to sustainability. If the engines can be further used without any problems, they do not have to be replaced by new units. This also helps to save valuable resources.

It has to be said that, overall, a hydrogen engine works no differently from any other internal combustion engine. It follows well-known, tried-and-tested principles of energy conversion. Nevertheless, engineers have faced and continue to face countless challenges that must be overcome in order to guarantee outstanding reliability and efficiency when an engine is powered by hydrogen.

Facing these different challenges is ultimately a purely conventional and solvable – but non-trivial – development task. To give a concrete example, all the engine’s components must meet particularly stringent leak-tightness requirements. This is because the molecules of hydrogen are very small. That’s why they can diffuse more easily. In addition, H2 has very poor lubricating properties. A specific solution has to be found for this as well. The constant exchange between developers and designers on the one hand and with users on the other is therefore particularly important and necessary – a fact that directly brings us to the CIMAC Congress where every three years, the large engine industry meets.

CIMAC is the voice of the large engine industry, a leading global non-profit association consisting of members in 27 countries in America, Asia and Europe. The CIMAC Congress is a unique opportunity to keep up to date with what is happening in the internal combustion engine industry. This is where experts from all over the world meet, gather information, discuss with each other, look for solutions and define standards.

Next year in Busan, from 13 to 17 June 2022, the Congress will be held for the 30th time. The overarching theme of climate protection plays a very prominent role at the congress as well as in its Technical Program, where technical, environmental, and regulatory trends, developments, opportunities and challenges are discussed.

There is simply no better place to learn about the latest developments and encouraging results in the large engine industry, including the hydrogen-ready engine. By 2025, the industry believes that – possibly after updates or specific retrofits – newly purchased stationary combustion engines for power and heat generation will be able to burn up to 100% hydrogen. Powered with green hydrogen, they will work without producing CO2.