The Hydrogen Economy Part III

Hydrogen Utilization

The fuel cell is one of several conversion technologies that can be fueled by hydrogen. Basically, hydrogen fuel cells operate like electrolysis in reverse: Hydrogen gas and oxygen from the air combine in a catalyzed electrochemical reaction to produce an electric current, heat and water, pure enough to drink. Aside from being pollution-free, fuel cells are quiet, and can achieve efficiencies that are two- to three-times greater than internal combustion engines. The scalability of fuel cells makes them ideal for a wide variety of applications – including laptops (50- 100 Watts) and central power generation (1-200 MW).

Although fuel cells have the potential to serve all sectors of the economy, today they are relatively expensive to build compared to our internal combustion engines. They will need further development to increase durability and bring down cost so they can compete economically.

We can use hydrogen in internal combustion engines (ICEs) , similar to the engines we have in our cars today, with slight modifications. Hydrogen burns much cleaner and more efficiently than gasoline which makes hydrogen ICEs a realistic near-term transition technology. However, fuel cells, with higher efficiencies and zero emissions will likely be a more popular utilization technology in the longer term. Reciprocating engines and combustion turbines are also under development to combust hydrogen in place of traditional fuels to efficiently generate electricity and thermal power with zero emissions. Once mature, these technologies can also find use for onsite power applications in homes, offices and industrial facilities. 

Carbon Sequestration

The use of fossil resources (natural gas, coal, petroleum) to produce hydrogen emits some carbon dioxide (CO2), a greenhouse gas. Technologies to capture and sequester (store) CO2 are under development.

We will need these technologies before large-scale hydrogen production from fossil resources contributes to the transition to a sustainable hydrogen economy.