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How close we are to achieving commercially viable large-scale photobiological hydrogen production by cyanobacteria: a review of the biological aspects.

Sakurai H, Masukawa H, Kitashima M, Inoue K - Life (Basel) (2015)

Bottom Line: The products of photobiological systems are H2 and O2; the H2 can be used as the energy source of fuel cells, etc., which generate electricity at high efficiencies and minimal pollution, as the waste product is H2O.Overall, production of commercially viable algal fuels in any form, including biomass and biodiesel, is challenging, and the very few systems that are operational have yet to be evaluated.In this paper we will: briefly review some of the necessary conditions for economical production, summarize the reports of photobiological H2 production by cyanobacteria, present our schemes for future production, and discuss the necessity for further progress in the research needed to achieve commercially viable large-scale H2 production.

View Article: PubMed Central - PubMed

Affiliation: Research Institute for Photobiological Hydrogen Production, Kanagawa University, Tsuchiya, Hiratsuka, Kanagawa 259-1293, Japan. sakurai@waseda.jp.

ABSTRACT
Photobiological production of H2 by cyanobacteria is considered to be an ideal source of renewable energy because the inputs, water and sunlight, are abundant. The products of photobiological systems are H2 and O2; the H2 can be used as the energy source of fuel cells, etc., which generate electricity at high efficiencies and minimal pollution, as the waste product is H2O. Overall, production of commercially viable algal fuels in any form, including biomass and biodiesel, is challenging, and the very few systems that are operational have yet to be evaluated. In this paper we will: briefly review some of the necessary conditions for economical production, summarize the reports of photobiological H2 production by cyanobacteria, present our schemes for future production, and discuss the necessity for further progress in the research needed to achieve commercially viable large-scale H2 production.

No MeSH data available.


Some scenarios for annual greenhouse gas (GHG) emission, UN IPCC. Due to uncertainty regarding future emissions and prediction of the outcome, probable ranges are shown for each stabilization targets.  Stabilization at 530–580 and  720–1000 ppm CO2-eq respectively in 2100. The upper level of the probable range of >1000 ppm CO2-eq line in IPCC scenario is also shown. (Adapted from Figure SPM4, IPCC, 2014: Summary for Policy Makers, the Climate Change 2014 [1]).
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life-05-00997-f001: Some scenarios for annual greenhouse gas (GHG) emission, UN IPCC. Due to uncertainty regarding future emissions and prediction of the outcome, probable ranges are shown for each stabilization targets. Stabilization at 530–580 and 720–1000 ppm CO2-eq respectively in 2100. The upper level of the probable range of >1000 ppm CO2-eq line in IPCC scenario is also shown. (Adapted from Figure SPM4, IPCC, 2014: Summary for Policy Makers, the Climate Change 2014 [1]).

Mentions: The concentration of atmospheric CO2 has been increasing since the era of the industrial revolution when it was estimated to be 270–280 ppm initially, rising to current levels of about 400 ppm. According to the fifth assessment report of the UN IPCC (United Nations Intergovernmental Panel on Climate Change) [1,2], the greatest contribution to the global increase in greenhouse gases comes from CO2 emitted by burning fossil fuels (65%) and land use changes (deforestation) (11%), followed by methane (16%), N2O (6%) and fluorocarbons, etc. (2%). Currently, the amounts of greenhouse gases emitted have continued to rise due to the increases in human activities and population growth. If we are able to stabilize the atmospheric greenhouse gases at 530–580 ppm-CO2 equivalent (approximately twice that of the pre-industrial level), one of the ICPP scenarios predicts that we will need to reduce global greenhouse gas emissions by 19%–47% in 2050 and 59%–81% in 2100 (relative to 2010 emissions) (Figure 1). Some scenarios predict that we will need to go beyond reduction strategies and achieve “negative emissions” by CO2 sequestration, etc. Economically advanced countries will likely be required to reduce emissions the most, perhaps by as much as 80% compared to present levels. Even if we succeed in stabilizing greenhouse gases at the level of 530–580 ppm CO2 equivalent, the global average temperature will rise around 2.0–2.2 °C relative to the 1850–1900 temperatures. Stabilizing emissions at a less-stringent level of 720–1000 ppm-CO2 equivalent, would still require substantial emissions reduction from current, largely unregulated levels, and result in the average temperature rising around 3.1–3.7 °C relative to the 1850–1900 temperatures. From all of these considerations, it is evident that we urgently need viable renewable energy technologies as part of a global strategy to drastically reduce CO2 emissions from burning fossil fuels and thus avert potentially catastrophic climate change.


How close we are to achieving commercially viable large-scale photobiological hydrogen production by cyanobacteria: a review of the biological aspects.

Sakurai H, Masukawa H, Kitashima M, Inoue K - Life (Basel) (2015)

Some scenarios for annual greenhouse gas (GHG) emission, UN IPCC. Due to uncertainty regarding future emissions and prediction of the outcome, probable ranges are shown for each stabilization targets.  Stabilization at 530–580 and  720–1000 ppm CO2-eq respectively in 2100. The upper level of the probable range of >1000 ppm CO2-eq line in IPCC scenario is also shown. (Adapted from Figure SPM4, IPCC, 2014: Summary for Policy Makers, the Climate Change 2014 [1]).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390889&req=5

life-05-00997-f001: Some scenarios for annual greenhouse gas (GHG) emission, UN IPCC. Due to uncertainty regarding future emissions and prediction of the outcome, probable ranges are shown for each stabilization targets. Stabilization at 530–580 and 720–1000 ppm CO2-eq respectively in 2100. The upper level of the probable range of >1000 ppm CO2-eq line in IPCC scenario is also shown. (Adapted from Figure SPM4, IPCC, 2014: Summary for Policy Makers, the Climate Change 2014 [1]).
Mentions: The concentration of atmospheric CO2 has been increasing since the era of the industrial revolution when it was estimated to be 270–280 ppm initially, rising to current levels of about 400 ppm. According to the fifth assessment report of the UN IPCC (United Nations Intergovernmental Panel on Climate Change) [1,2], the greatest contribution to the global increase in greenhouse gases comes from CO2 emitted by burning fossil fuels (65%) and land use changes (deforestation) (11%), followed by methane (16%), N2O (6%) and fluorocarbons, etc. (2%). Currently, the amounts of greenhouse gases emitted have continued to rise due to the increases in human activities and population growth. If we are able to stabilize the atmospheric greenhouse gases at 530–580 ppm-CO2 equivalent (approximately twice that of the pre-industrial level), one of the ICPP scenarios predicts that we will need to reduce global greenhouse gas emissions by 19%–47% in 2050 and 59%–81% in 2100 (relative to 2010 emissions) (Figure 1). Some scenarios predict that we will need to go beyond reduction strategies and achieve “negative emissions” by CO2 sequestration, etc. Economically advanced countries will likely be required to reduce emissions the most, perhaps by as much as 80% compared to present levels. Even if we succeed in stabilizing greenhouse gases at the level of 530–580 ppm CO2 equivalent, the global average temperature will rise around 2.0–2.2 °C relative to the 1850–1900 temperatures. Stabilizing emissions at a less-stringent level of 720–1000 ppm-CO2 equivalent, would still require substantial emissions reduction from current, largely unregulated levels, and result in the average temperature rising around 3.1–3.7 °C relative to the 1850–1900 temperatures. From all of these considerations, it is evident that we urgently need viable renewable energy technologies as part of a global strategy to drastically reduce CO2 emissions from burning fossil fuels and thus avert potentially catastrophic climate change.

Bottom Line: The products of photobiological systems are H2 and O2; the H2 can be used as the energy source of fuel cells, etc., which generate electricity at high efficiencies and minimal pollution, as the waste product is H2O.Overall, production of commercially viable algal fuels in any form, including biomass and biodiesel, is challenging, and the very few systems that are operational have yet to be evaluated.In this paper we will: briefly review some of the necessary conditions for economical production, summarize the reports of photobiological H2 production by cyanobacteria, present our schemes for future production, and discuss the necessity for further progress in the research needed to achieve commercially viable large-scale H2 production.

View Article: PubMed Central - PubMed

Affiliation: Research Institute for Photobiological Hydrogen Production, Kanagawa University, Tsuchiya, Hiratsuka, Kanagawa 259-1293, Japan. sakurai@waseda.jp.

ABSTRACT
Photobiological production of H2 by cyanobacteria is considered to be an ideal source of renewable energy because the inputs, water and sunlight, are abundant. The products of photobiological systems are H2 and O2; the H2 can be used as the energy source of fuel cells, etc., which generate electricity at high efficiencies and minimal pollution, as the waste product is H2O. Overall, production of commercially viable algal fuels in any form, including biomass and biodiesel, is challenging, and the very few systems that are operational have yet to be evaluated. In this paper we will: briefly review some of the necessary conditions for economical production, summarize the reports of photobiological H2 production by cyanobacteria, present our schemes for future production, and discuss the necessity for further progress in the research needed to achieve commercially viable large-scale H2 production.

No MeSH data available.