Comparative Study of Hydrogen Production Methods: Electrolyzing and Reforming
Mohamad Nour, Chaiban Haykal and Nazih Moubayed
Faculty of Engineering 1, Lebanese University
El-Arz Street, El-Kobbeh, Tripoli, Lebanon
E-mail: nmoubayed@ieee.org
ABSTRACT
Fuel cells, which are one of non pollutant energy
production sources, need hydrogen for their
functioning. This paper represents the production of
hydrogen from water electrolyzing by first, explaining
the process thermodynamically, chemically and
electrically and second, by specifying some types of
electrolyzing. Also, hydrogen production from biomass
by aqueous phase reforming the processes and Plasma
reforming of hydrocarbon fuels will also be explained
in the same way. Finally, a comparison between
electrolyzing methods and reforming strategies is
studied.
KEYWORDS
Alkaline Water Electrolyzer; Solid Water Electrolyzer;
Solid Oxide Electrolyzer; Aqueous Phase Reforming;
Hydrocarbon Reforming.
1 INTRODUCTION
The world is heading to the era of using and
developing new, clean and renewable energy
resources, and that’s because of the massive use of
the current nuclear and fossil fuel energy that
causes serious pollution, climate change and waste
generation [1-10]. For that matter, using
renewable source of energy instead is getting quite
spectacular in the recent years [11-26]. Moreover,
the total energy produced by the renewable energy
reached about 1230GW in 2009, 7% more than in
the 2008, which is almost the quarter of the
worldwide energy produced (4800GW), where the
wind power takes the lead by increasing of 38GW.
The photovoltaic solar energy has increased. As
well for the grid-connected technology, it reaches
up to 21GWp [27],[28]. The emerging challenge is
based on increasing the production of electricity
from renewable energy, although other challenges
rise concerning different subject like storing [29-
40], distributing, managing, etc [41-43].
Hydrogen is a suitable way to face these
challenges and to create a new energy system. It is
true that the lightest element is hydrogen, it is
even 15 lighter than air, but, on the other hand, it
has the Highest Heating Value (HHV) 39.42
kWh/Kg, that is, 2.5 and around three times more
energetic than methane and gasoline, respectively
[10], [44-47].
Despite being a plentiful element, it is hardly
found in his pure state. Also despite that water is
very plentiful on earth, about 4% of hydrogen is
produces out of it and the rest 96% is produced
from fossil fuels [48-52]. By the chosen materials,
the methods to produce hydrogen are classified.
Starting with fossil fuel as a source, steam
reforming and partial oxidation of hydrocarbons,
although, coal gasification are used [10], [49],[50].
In addition, using biomass as a source and using
the same procedures, hydrogen can be obtained.
Economically speaking, producing hydrogen from
fossil fuel is nothing more than a temporary or
transition state, because the future is looking
forward to use water for that matter.
Electrolyzing is the most important way to
produce hydrogen. It is done by passing a current
into the water to dissociate it. After purifying the
obtained hydrogen, its purity could rise up to
99.9%, which is very good hydrogen to be used in
fuel cells. Yet, a suggestion is made that is to build
the electrolyzing facility near hydraulics power
station where there is both water and electricity.
This paper discusses and compares the hydrogen
production methods. It is divided in six Sections.
Section 2 presents the fundamentals of water
electrolyzing. Hydrogen production from
electrolyzer or by reforming are respectively
studied in Sections 3 and 4. A comparison and
discussions between the presented electrolyzers,
ISBN: 978-0-9891305-3-0 ©2013 SDIWC 176