The world’s rapidly increasing population and global industrialization continues to create a huge demand for energy. According to the International Energy Agency (IEA) 2002 World Energy Outlook Reference Case, the world energy demand will grow by more than 65%, with fossil fuels, most namely coal, natural gas and gasoline, meeting 90% of that predicted increase. Other projections for the world’s growth in energy demand over the next decades predict that the world will use 1.2 to 2 times more fossil fuel energy in the years 2030 and 2050 than in 2005. World electricity demand is predicted to double by 2030 and triple by 2050, requiring the construction of nearly 5,000 Giga-watts of new generation capacity, which is equivalent to adding six times the current United States electric generating capacity. According to some estimates (1), the required additional energy generation will cost about $4.2 trillion, plus energy transmission & distribution (T&D) costs of about $6.6 trillion (2004 U.S. dollars).
The use of fossil fuels to generate the energy increased more than 150-fold rising from 12% of the modest energy use of the 1850s to 79% of the energy production in 2000. In 2005, fossil fuels were contributing 81% of the world’s energy supply, with 88% an even greater share in the U.S. In the U.S. currently more than 500 coal-fired plants supply about 50% of the electricity consumed in the U.S. Since the U.S. electricity demand is expected to increase by almost 50% by the year 2030, new energy generating systems have to be built. According to a 2008 Edison Electric Institute (EEI) study, the U.S. will have to generate at least 151 Gigawatts of new energy, enough to power 75 million homes. The projected energy investments – aimed at meeting new energy demand and replacing aging power plants – are estimated to cost about $457 billion for building new plants and about $900 billion for new transport and distribution (T&D) technology.
Based on the assumption that the world’s increased energy demand in the next decades is met in a ‘business-as-usual’ scenario, relying heavily on the use of fossil energy sources, the already high global carbon dioxide emissions are expected to increase by 70 percent. In 2005, the U.S. alone emitted about 7 billion tons of the known green house gas carbon dioxide (CO2) into the atmosphere, 2 billion tons due to combustion of fossil fuels for electricity generation.
The United States presently consumes 31% of the world's total oil production, yet possesses only 2% of the world's proven oil reserves. Petroleum imports supply more than 55% of U.S. domestic needs and these imports are projected to increase to more than 68%. Even though the world does not seem to run out of fossil energy sources, such as coal, it seems to be running out of cheap and easy-to-extract oil and gas. (2,3,4).
1 Casten T.R. & Downes B. Skeptical Inquirer 29(1): 25-33 (2005)
2 Cavallo A., Nat. Resources Res. 11(3): 187 (2002)
3 Cavallo A., Science 316(5827): 980 (2007)
4 Rogers M., Oil Gas J. 8 Nov.: 16 (2004)
We at SGT believe that the world urgently needs sustainable energy alternatives to keep pace with the ever increasing world energy demand. As a nation we must reduce our dependence on foreign supplies of energy in a manner that is affordable and while preserving environmental quality. We believe that our nation can achieve this goal by shifting to a bio-fuels-based economy.
SGT further believes that the world urgently needs clean energy alternatives to minimize the risk of climate change due to carbon emissions.
Before peak oil production happens, we need to find sustainable bio-energy sources. Earth’s major ecosystems show strong signs its environmental capacity is being reached. This mandates a search for clean energy sources.
Indeed, the huge increase in fossil fuel use over the past century and a half lead to significant emissions of fossil fuel derived waste streams, most prominently CO2, oxides of sulfur and nitrogen, heavy metals, soot and other particulate matter into literally all major global biogeochemical cycles. By the beginning of this millennium the world’s emission of carbon dioxide (CO2) into the atmosphere due to fossil energy production and conversion amounted to about 14 billion (14 Giga) tons annually. The levels of the green house gas CO2 in the atmosphere are now increasing faster than at any time in the last 20,000 years and rose from 320 ppm in 1960 to more than 380 ppm by 2008. The recorded global rise in atmospheric carbon dioxide is attributable to the combustion of fossil fuels worldwide. By the beginning of the 21st century it is becoming more and more obvious that the world’s fossil fuel dominated energy supply systems visibly impose tremendous environmental burdens at local, regional and global levels. For example, the measured rise in global average surface temperatures of about 0.75 +/- 0.20°C since the 1880s and the obvious changes in the world’s climate (which have been observed worldwide over the past few decades) have been attributed to human activities rather than natural influences.
At the beginning of this century, the world faces two great challenges:
1. Providing affordable energy in a sustainable way to an increasing world population.
2. Providing clean energy without damaging or interfering with the major global biogeochemical cycles.
We at SGT believe that the world urgently needs clean sustainable energy alternatives to protect the current status of our biosphere for future generations.
SGT believes that combined carbon capture and bio-waste fuel technologies should not compete with human food production. Our SGT business model does not require food because we use waste streams to run our bio-reactors.
Hydrogen is an inexhaustible, emission free fuel. Hydrogen, actually hydrogen gas (H2 or molecular hydrogen) holds tremendous promise as an alternative sustainable fuel. It is the most efficient and cleanest burning fuel known to man. H2 is a high energy-supplying, clean-burning and safe gas. Currently, hydrogen is produced from many domestic sources of energy, including fossil fuels, such as natural gas and coal, via industrial processes including coal gasification and steam reforming. Both currently used industrial hydrogen production processes require high energy inputs, and are accompanied with the release of green house gases (GHGs) and other noxious byproducts, such as carbon monoxide. Renewable energy resources, such as solar radiation, wind, and biomass, as well as nuclear energy can also be utilized to produce hydrogen gas either via electrolysis or other reforming processes. The diversity of hydrogen sources and the high energy efficiency benefits of hydrogen fuel cells make the widespread use of hydrogen for transportation and stationary power an important step in protecting the future energy security of the United States.
We at SGT are firmly convinced that hydrogen is the key to a cleaner energy future. However, generation of hydrogen from the diverse sources and its use as fuel is only feasible if it can be produced cleanly and economically. Once generated with the help of hydrogen-generating microbes, hydrogen’s conversion into usable energy through fuel cells emits no pollution and no greenhouse gases.
Atomic hydrogen (H) is the most abundant chemical element in the universe and - bound in the form of water (H2O) or in the diverse molecules of renewable biomass – also the single most abundant chemical element on planet Earth. Hydrogen naturally joins with itself to form molecular hydrogen (H2) or also called hydrogen gas. Hydrogen gas – with a molecular weight of 2 g/mol - is the lightest gas known to man.
Hydrogen gas is not only light but it also has a very low solubility in water, a property which allows its low cost and efficient extraction from aqueous environments, such as a microbe-operated bio-reactor. Only 1.93 ml of hydrogen gas dissolve in 100 ml of water at standard pressure and temperature.
Since hydrogen gas is light, it occupies a rather large volume at STP. One gram of hydrogen gas (at 0°C and 1 atm) occupies about 11.13 liters. This feature hampers its easy and cost-effective use as a transportation fuel and rather favors its immediate on-site use in combination with coupled hydrogen energy conversion systems, such as fuel cells.
Hydrogen gas is safe. Ever since the historic Lakehurst tragedy in the 1930s which led to the rapid destruction of the giant hydrogen gas filled zeppelin “Hindenburg,” hydrogen gas gained a bad public reputation as a highly dangerous flammable fuel. The truth is, hydrogen gas is indeed flammable over a very wide range of concentrations (from 6.2% to 71.4% in air), but at ambient temperatures it is chemically very stable. Hydrogen gas won’t burn until the molecule is disrupted by some form of ignition energy. Hydrogen gas is a high energy fuel. H2 has the highest energy content per unit of weight (at 52,000 Btu/lbs) of any known industrial fuel.
Bio-hydrogen is hydrogen gas produced by certain life forms, such as hydrogen producing bacteria. Bio-hydrogen production is performed in special bioreactor environments where biological organisms generate hydrogen gas in the presence of either sun light or from hydrogen-containing renewable biomass, such as glucose, sucrose, maltose, glycerol or starch. In the past one hundred years, scientists isolated and studied many hydrogen gas-producing microorganisms, including green algae, cyanobacteria and eubacteria. Especially members belonging to the latter group, such as Enterobacteria, Thermotogae, and Clostridia, have been reported to generate bio-hydrogen from diverse sugar feedstock mostly via fermentative pathways. To achieve this remarkable feat, these bacteria rely on a unique class of evolutionary ancient enzymes (bio-catalysts) termed hydrogenases. With the help of these hydrogenase enzymes hydrogen producing bacteria generate hydrogen gas (H2) from feedstock-derived reduction equivalents (electrons) and protons (H+).
Bio-hydrogen production rates by most of the researched microorganisms are currently low and only between 0.37 to 2.3 moles H2 per mole of glucose have so far been reported. Considering the high theoretical value of production of 4.0 moles H2 per mole of glucose and the prospect of sustainable feeding of future bio hydrogen systems with renewable biomass-derive glucose and other carbohydrates, hydrogen production with the help of biological organisms certainly will have a bright future in a fossil energy depleted earth of tomorrow. Bio hydrogen gas can be generated safely and – if immediately used on site with the help of suitable hydrogen converting technologies, such as a fuel cell – at competitively low operational costs devoid of transportation and distribution. To give an example, the international oil company BP spent (2006) about $1.7 billion per year for operational safety at its U.S. refineries alone.
SGT’s patent pending microorganisms generate high amounts of hydrogen gas with the patent pending process from diverse bio waste feedstock, including bio-diesel refinery waste, brewery waste, and paper waste. We foresee a great future for bio-hydrogen as a sustainable, clean, safe and decentralized energy source.
Public skepticism still exists about the safety of hydrogen gas. Most people express mixed feelings about carrying around pure hydrogen in a moving vehicle. Many cite the vivid images of the Hindenburg ablaze, or the 1986 Challenger catastrophe, or the Hydrogen bomb as testaments to the danger of hydrogen. Fortunately, these exceptional “explosions” and accidents have little bearing on the safety of hydrogen. it is especially safe when bio-hydrogen is generated under ambient temperatures and used at normal pressures in combination with quietly and highly efficiently running hydrogen fuel cell technology.
Storage and use of (even compressed) hydrogen is indeed a good deal safer than gasoline or diesel. Because H2 is so light, hydrogen quickly disperses and floats skyward under conditions of a leak, rather than pooling or soaking into materials, such as clothing or car seats, like in the case of leaking (and waiting to ignite) gasoline. In comparison with gasoline or diesel, spilled hydrogen gas does not soak into the soil, does not pollute ground water, nor cause other forms of environmental disaster. Tests conducted at the College of Engineering at Miami University showed that even if leaked hydrogen gas should become ignited it fared much better when compared side-by-side with gasoline leaking from a car. In their experiment, 3000 cubic feet of hydrogen was leaked per minute from the hydrogen fuel tank of a car and set on fire. Over the course of the burn, temperature sensors inside the vehicle did not measure an increase of more than 1 or 2 degrees centigrade anywhere inside the vehicle. The temperature of the surface of the outside of the vehicle did not climb above that of a vehicle sitting in the sunshine!
Bio-hydrogen can be safely produced at ambient temperatures and pressures with the help of natural (non-genetically modified) biological microorganisms. Bio-hydrogen can be economically produced from diverse biomass waste streams with minimum energy inputs (i.e. at ambient temperatures and normal pressures). Microbial hydrogen production is – in contrary to industrial hydrogen generation from fossil fuels via gasification or similar methods – not accompanied with the generation of toxic by products such as carbon monoxide. The proprietary microbes working in SGT’s bio-hydrogen reactor prototypes only generate hydrogen and carbon dioxide gas from the supplied biomass waste feedstock. No toxic by-products are co-generated during SGT’s bio-hydrogen process and the carbon dioxide gas generated during the first bio-hydrogen generating process is completely used up by the algae in the coupled algae photobioreactor unit.
Bio-hydrogen, which is the generation of hydrogen gas (H2) with the help of microorganisms, has significant advantages over the currently favored bio-ethanol generation from corn and sugar cane.
1. Hydrogen gas is non-toxic to humans and – in the presence of oxygen – burns clean into water without the generation of environmentally critical by-products, such as carbon dioxide (CO2) or nitric oxides
- for comparison, in the presence of oxygen bio-ethanol burns into water and the green house gas CO2
2. Hydrogen gas – with 127 kJ/g – has the highest heating value per weight amongst all common fuels, such as gasoline, natural gas or Diesel
3. Hydrogen gas can be operated safely in bio-fermentation platforms and – in combination with fuel cell technology – can be converted into usable forms of energy, most importantly electricity, with high conversion efficiencies
4. Fermentative hydrogen gas production – in comparison to bio-ethanol – does not require a highly energy-intensive distillation process for fuel extraction
5. The feedstock versatility of bio hydrogen gas production
6. Utilizing suitable microorganisms hydrogen gas can be generated from diverse waste sources, including paper waste, brewery waste, food industry waste streams
7. Bio-hydrogen gas generation allows the effective and low cost capturing of the concomitantly generated green house gas CO2 and opens the perspective for the development of efficient “carbon sink technologies”