8TH ASIAN PACIFIC PHYCOLOGICAL FORUM
Algal biophotovoltaic (BPV) device for generation of bioelectricity using
Synechococcus elongatus (Cyanophyta)
Fong-Lee Ng
1
&
Siew-Moi Phang
1,2
&
Vengadesh Periasamy
3
&
John Beardall
4
&
Kamran Yunus
5
&
Adrian C. Fisher
5
Received: 25 January 2018 / Revised and accepted: 14 May 2018
#
Springer Science+Business Media B.V., part of Springer Nature 2018
Abstract
The exploitation of renewable energy sources for delivering carbon neutral or carbon negative solutions has become challenging
in the current era because conventional fuel sources are of finite origins. Algae are being used in the development of
biophotovoltaic (BPV) platforms which are used to harvest solar energy for bioelectricity generation. Fast-growing algae have
a high potential for converting CO
2
from the atmosphere into biomass and valuable products. In photosynthesis light-driven
splitting of water occurs, releasing a pair of electrons and generating O
2
. The electrons can be harvested and converted to
bioelectricity. In this study, algal biofilms of a tropical cyanobacterial strain Synechococcus elongatus (UMACC 105) were
formed on two types of electrodes, indium tin oxide (ITO) and reduced graphene oxide (rGO), and investigated for use in the
algal biophotovoltaic (BPV) device. The highest maximum power density was registered in the rGO-based BPV device (0.538 ±
0.014 mW m
−2
). This illustrates the potential of this local algal strain for use in BPV devices to generate bioelectricity in both the
light and dark conditions.
Keywords Algal biophotovoltaic (BPV) device
.
Bioelectricity
.
Cyanophyta
Introduction
Sunlight is the most abundant and sustainable source of ener-
gy available to humanity. Annual solar energy production is
approximately 120,000 TW and estimated to be about 20,000
times more than the present annual energy consumption of the
world (Blankenship et al. 2011). There is a huge drive to
develop low carbon technologies and how to capture and store
radiant energy for societal use is one of the greatest challenges
of our age. The total amount of biomass produced by photo-
synthesis is equivalent to 4 × 10
21
J of energy, approximately
10 times the total annual global energy consumption (Helmut
2005). Algae are known to be one of the most photosynthet-
ically efficient organisms, harnessing solar energy into the
production of a diverse range of products such as
biopharmaceuticals and bioenergy (Lim et al. 2010).
Cyanobacteria (Cyanophyta) or blue green algae are a dis-
tinct group of photosynthetic organisms. They are the only
prokaryotes with oxygenic photosynthesis. Cyanobacteria
are prokaryotes and as such the energy-transducing mem-
branes are not located in mitochondria or chloroplasts as in
higher plants. They are contained in a densely packed mem-
brane system (thylakoids) in the cytoplasm (Binder 1982).
Cyanobacteria generally harness 0.2 to 0.3% of the solar en-
ergy. The amount of energy that passes through the
cyanobacteria exceeds by more than 25 times the energy de-
mand of human populations and an estimated 1000 times the
energy produced by all the nuclear plants on Earth. On a
global scale, Cyanobacteria fix an estimated 25 Gigatonnes
of carbon from CO
2
per year into energy-dense biomass
(Pisciotta et al. 2010).
* Fong-Lee Ng
fonglee_ng@yahoo.com
* Siew-Moi Phang
phang@um.edu.my
1
Institute of Ocean and Earth Sciences (IOES), University of Malaya,
50603 Kuala Lumpur, Malaysia
2
Institute of Biological Sciences, Faculty of Science, University of
Malaya, 50603 Kuala Lumpur, Malaysia
3
Low Dimensional Materials Research Centre (LDMRC),
Department of Physics, University of Malaya, 50603 Kuala
Lumpur, Malaysia
4
School of Biological Sciences, Monash University,
Clayton, Victoria 3800, Australia
5
Department of Chemical Engineering and Biotechnology, University
of Cambridge, Philipa Fawcett Drive, Cambridge CB3 0AS, UK
Journal of Applied Phycology
https://doi.org/10.1007/s10811-018-1515-1
@Phil_Robichaud
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