Researchers at the University of Minnesota-Twin Cities believe they have found a unique species of bacteria, Geobacter sulfurreducens, that can convert wastewater organic compounds into electricity using a low cost carbon (graphite) electrode.
“Other species of bacteria may produce just as many electrons as they oxidize available fuels, but their cell membranes act like an insulator for electron transport,” said Daniel Bond, a microbiologist at the University of Minnesota-Twin Cities. “With Geobacter, it’s the difference between a rickety one-land bridge and a modern 12-lane highway. The electrons pass easily through internal membranes and cell walls and hop onto the electrode.” As each “hop” requires them to travel about 10 Angstroms.
Geobacter has proteins that guide electrons all the way to the electrode. “This makes Geobacter unique in comparison to other bacteria,” Bond said. “Because of the distances involved, we know that multiple proteins are involved, which adds to the complexity and why we can’t just clone a gene into E. coli to do this.”
Why is this important to the future of energy?
While traditional batteries and fuel cells often use expensive precious-metal catalysts (e.g. platinum) to strip electrons off the fuel source to generate electricity, microbial fuel cells use biological agents to do the heavy work.
A microbial fuel cell based on Geobacter would require only an inexpensive form of carbon (graphite) to help the bacteria transfer electrons onto the surface of electrodes. This novel design of microbial fuel cells could be scaled to efficiently convert waste organic matter (e.g. sewage, food waste) to electricity.
Despite the hype, algae is more history than science fiction. In fact it is already the world's dominate source of energy. Petroleum is just chemical energy stored in the form of hydrogen-carbon bonds that were assembled by ancient sea-living microbes (diatoms). So, oil is in essence the result of ancient algae growth!
So instead of extracting reserves of oil, we can 'grow energy' using efficient biochemical pathways of algae (and bacteria) that eat carbon and, then using the power of light, bind it with hydrogen to produce bio-oil that can be used as a source of energy (via engine or fuel cell) or as a feedstock for biomaterials.
60 Minutes recently aired a program on the future of coal power featuring Duke Energy CEO Jim Rogers (an advocate of longer term 'Cathedral Thinking' carbon reduction) and leading climate scientist James Hansen (an advocate of a moratorium on building coal plants).
The CBS report was solidly mainstream in framing coal as central to the conversation on energy, environment and global economic development- but it failed to move the conversation beyond ideas that have existed for several decades.
Time for Big Ideas, not Big Battles Coal is the world's fastest growing source of energy due largely to growth outside the United States. And despite all the rapid growth rates expected with wind and solar, coal is likely to gain global market share in the years ahead.
So this is not just a conversation about US policy and US-based utilities! And there is no way to just 'wish' coal away. We must develop low cost carbon solutions that can be applied around the world within existing power plants. And everyone agrees - these low cost solutions do not exist today!
CBS Producers missed an opportunity to introduce more advanced non-geoengineering strategies to carbon neutralization and left viewers stuck at ringside watching the same old 'pro' vs 'anti' battle.
Carbon's Molecular Dance between Oxygen and Hydrogen Carbon is a 'sticky' molecule that interchangeably binds with oxygen and hydrogen based on its journey through biochemical pathways or via human induced energy conversion (e.g. power plants and combustion engine).
Human beings have a choice to approach carbon solutions through geo-engineering (shoving it underground), or as bio-engineers who can bind carbon with hydrogen for use as a hydrocarbon fuel (for transportation or onsite electricity generation) or a bio-feestock for industrial applications. CBS viewers would have been better off understanding the long-term view of carbon rather than watch a debate without a viable solution. (Continue Reading Below).
Coal is the world's fastest growing source of energy, and at the center of the debate over advancing our efforts to reduce CO2 emissions even as we attempt to meet the demands of a global doubling of energy consumption in the decades ahead.
'Clean' vs 'Cleaner' While one side of the debate spectrum ridicules the concept of 'Clean Coal', the other side is pushing forward down the road to 'Cleaner' ways to convert coal energy into electricity that goes far beyond today's 'coal fire' combustion power plants.
Via a process known as 'gasification' we can remove much of the carbon from coal to create a cleaner hydrogen-rich synthetic gas (syngas). Industrial scale fuel cells can then convert this syngas chemical energy into electricity. The challenge is scaling up fuel cells to meet the challenge!
The milestone marks a key step towards non-combustion based conversion using 'low-cost Solid Oxide Fuel Cells (SOFC) technology for coal-based power plants and other power generation applications' using carbon heavy feedstocks such as syngas, natural gas and biofuels.
Integrated gasification fuel cell plants are expected 'to achieve an overall operating efficiency of greater than 50 percent—15 percentage points higher than today’s average U.S.-based coal-fired power plant—while separating at least 90 percent of the carbon dioxide emissions for capture and environmentally secure storage.'
The US Department of Energy hoopes to have a a 250-kilowatt to 1-megawatt fuel cell module demonstration by 2012; a 5-megawatt proof-of-concept fuel cell system to demonstrate system integration, heat recovery turbines, and power electronics by 2015; and then a full-scale demonstration of a 250- to 500-megawatt integrated gasification fuel cell power plant by 2020.