Page 43 - Introduction to Transfer Phenomena in PEM Fuel Cells

32 Introduction to Transfer Phenomena in PEM Fuel Cells

Figure 1.13. Different types of fuel cells

The solid oxide fuel cell (SOFC) is attractive for stationary applications
because its very high operating temperature (around 800°C) makes it
possible to use natural gas directly without reforming. In addition, the
residual heat can be exploited in turn directly, or used to produce electricity
using a gas turbine. In this case, the overall yield could reach 80%. Figure
1.13 summarizes the different types of fuel cells.

1.2.2. Fuel cell and their applications

Fuel cells would be a very useful accompaniment to the choice of
available energy, because they provide electrical energy for uses currently
limited in energy capacity. For example, one of the most monotonous things
is laptops. Their limitation lies in their energy reserves since they have an
autonomy of only 2 hours. Existing fuel cells today would give laptops an 8-
hour battery life. After that, a quick refill of chemical fuel would allow the
user to continue his work. Each sector requires fuel cells for different
reasons, as described in the following sections. Fuel cells have multiple
applications that are divided into several categories:
– automobile: vehicle, bus, etc.;

– stationary: generation of heat and electricity (residential, public
building, e.g. swimming pool, hospital, school, apartments and emergency
generator);