Wasserstoff

A new project led by Fraunhofer IMM develops the next generation of methanol reformers to convert the liquid energy back into H2 and CO2.

© iStock/smirkdingo

Hydrogen (H2) may be “the fuel of the future” but the challenge of transporting it presents a costly headache. That’s why energy experts are betting on methanol (CH3OH, produced by reacting H2 with CO2): not only does it travel easily but the alcohol has a higher energy density than compressed hydrogen. The challenge, however, is how to convert the methanol back into H2 gas for immediate use in fuel cell applications.

This is the background to a new project from the Fraunhofer Institute for Microengineering and Microsystems (IMM). It develops the next generation of methanol reformers to convert the liquid energy back into H2 and CO2 using steam for use in lightweight applications like cars. The problem with existing reformers is the catalysts are unsuitable for moving vehicles, added to which the systems are bulky and require a lot of heat.

The IMM team have been working on solutions to overcome these obstacles and are developing a new kind of reformer with a power output of 35 KW, due to be completed mid-2022. The prototype uses a compact heat converter comprising of up to 200 catalyst-coated plates in a stack.

“We are opting for catalyst coatings containing precious metals similar to those used in automotive catalytic converters, because there is no attrition with these coatings,” explains Dr Gunther Kolb, division director at Fraunhofer IMM, in a press release. “Less catalyst material is required as a result. Because our catalyst materials also have a higher activity, the amount of catalyst required is reduced even further, and consequently the costs.”

Furthermore, Kolb’s team are reusing the heat generated in the fuel cell by off-gas to warm the plates. “By utilizing the waste heat, we achieve excellent heat integration and high system efficiency,” he says. They will also develop a reformer capable of providing 100 kW for maritime applications.