But the technology also has the potential to take on one of tomorrow's big issues: How do we integrate renewable energy into our transport sector?
Diesel vehicles emit both particles and NOx gases. Today, it is required to use particle filters, while NOx filters will be the next thing on the list.
In a new project, which will run over the next three years, researchers from the Materials Research Division at Risø DTU and the firm Amminex A/S will develop new materials that can clean the diesel exhaust of toxic NOx emissions. They will do this by using a stable and safe storage of ammonia in a mixture of different metal salts.
"There is a huge potential in the use of ammonia for cleaning gases from diesel vehicles and for energy storage. Liquid ammonia in itself is not safe to carry on a vehicle, but by using the new ammonia storage techniques, one can easily and safely transport it, "explains Tejs Vegge, senior scientist at Risø DTU.
The researchers' challenge of the project will include finding the right combination of materials properties to release exactly the right quantities of ammonia at the right temperatures. For this purpose they use advanced computational methods and supercomputers to predict the properties of the new materials before they are manufactured.
"We also want to integrate low-temperature fuel cells into the project, as waste heat from the fuel cell can be used directly to release ammonia. The hope is that we in this way will develop a technique that makes it possible to use ammonia, for example produced via electrolysis driven by the electricity from renewable energy sources, as an efficient energy storage medium. And exactly storage of renewable energy in a lightweight, compact and energy efficient way is in high demand," says Tejs Vegge.