How biogas compares to other renewable and alternative fuels?

Individual features in various renewable fuels make them stand out, but a more thorough comparison clearly shows that biogas is the strongest all-around option for heavy-duty transport. Not only now, but many years into the future as well.

There is a lot of debate within heavy-duty transport on what would be the right fuel of choice for the future in terms of sustainable development, encompassing economical, environmental and social dimensions. Instead of taking a step back to look at the big picture, the discussion tends to focus on individual features, which makes it difficult to have a clear overview. Some of the key renewables and zero/low emission solutions are performing better in one area but need development in another. A comparison of the key features shows that biogas performs best overall. We will now look at these factors in more detail.

Many of the most promising renewables and zero/low emission solutions currently being discussed are either in early development on some feature, insufficient in volume to meet demand, problematic in their environmental impact or their total cost of ownership is very high. Of the four renewables and zero/low emission solutions in question; biogas, HVO (hydrotreated vegetable oil), electricity and hydrogen, biogas rises above the rest in terms of readiness, total cost, availability and sustainability.

Large-scale distribution always requires a comprehensive infrastructure

Existing infrastructure is a key factor. In the case of hydrogen, the infrastructure is practically non-existent and in terms of electricity, the charging infrastructure is missing for heavy-duty transport. With diesel, the infrastructure is vast, and gas infrastructure comes in second place in terms of size. But when companies want to reduce their emissions now, clearly the best solution in this regard is to choose biogas.

Gasum and other players in the industry share a view, that biogas will continue to play an important role in the future, not only as a transitional solution.

“Electricity and hydrogen will become more common over the years, but their large-scale commercialization will still take quite some time. Biogas has its place now and, in the future,” says Jussi Vainikka, Senior Business Development Manager, Gasum.

Natural gas, on the other hand, may lose its relevancy at some point in the future, being replaced by power-to-gas, ie Renewable Fuels of Non-Biological Origin (RFNBO) and biogas.

Development stages of renewable fuels vary significantly

Almost all hydrogen in Europe is made from natural gas and is called grey hydrogen. However, the public attention is focused on the potential of green hydrogen, made with renewable electricity. Green hydrogen is made from water using an electrolyser to produce oxygen and hydrogen. The challenge is that the process requires a significant amount of green electricity, which does not yet exist in sufficient amounts. Electrolysers are also very expensive, and would require considerable product development to lower the cost of the technology. For this reason, hydrogen has a remarkably high price per kilo.

HVO (hydrotreated vegetable oil), is known as a renewable, new generation diesel. The challenge for the otherwise promising fuel is arrow pool of raw materials, which currently consists of different vegetable oils and animal fats. Development work around other feed-stock, e.g. algae-based diesel continues, but no real breakthrough to increase volumes has yet taken place.

”Biogas has a very wide range of raw materials. Inter Alia Volvo Trucks has analyzed the issue in terms of volumes and found that biogas alone could replace over 20 percent of the world's current diesel consumption,” Vainikka says.

Power-to-gas, also known as electric fuels or e-fuels, are the next step in the evolution.

"Where a significant part of the world's diesel could be replaced by biogas potential, electric fuels have even greater potential," he states.

In the production process of electric fuels, renewable electricity is used to turn water into green hydrogen through electrolysis, which is then methanated by adding carbon dioxide. This fuel is known as green gas but also synthetic methane, or RFNBO (Renewable Fuels of Non-Biological Origin).

The potential of green methane is significantly higher than of biogas and increases as renewable power becomes more abundant.

Biogas has the best total cost of ownership

When looking at the total cost of selected fuels / powers, biogas also emerges as the most cost-effective option.

The total cost of hydrogen-powered heavy-duty vehicles is remarkably high, not only due to the price of hydrogen but because of theel cells in the vehicles. Hydrogen is not burned, but converted by fuel cells into electricity and thus into kinetic energy. Fuel cells are currently very expensive. Where the purchasing price of an electric truck is even three times that of a diesel truck, with hydrogen the price is multiple times higher.

”HVO is more than ten euro cents per liter more expensive than diesel, which means that the total cost is higher than with biogas.”

What makes the total cost of a biogas vehicle relatively inexpensive? The vehicle has a moderately higher purchasing price compared to diesel but the fuel costs are lower.

Aside from the total costs, filling time can also be equated to costs while on the road and on a tight schedule.

“In heavy-duty vehicles, it takes about five minutes to refuel with diesel or liquefied biogas. To achieve the same range, it takes about 15 minutes to refuel a hydrogen truck and tens of minutes at best to charge an electric truck, depending on the charging technology,” Vainikka concludes.

16.11.2021