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New Process Allows Fuel Cells To Run On Coal
Zothecula writes "Lately we're hearing a lot about the green energy potential of fuel cells, particularly hydrogen fuel cells. Unfortunately, although various methods of hydrogen production are being developed, it still isn't as inexpensive or easily obtainable as fossil fuels such as coal. Scientists from the Georgia Institute of Technology, however, have recently taken a step towards combining the eco-friendliness of fuel cell technology with the practicality of fossil fuels — they've created a fuel cell that runs on coal gas."
For better or worse, coal won't run out any time soon, in fact we have a huge amount right here in the US. It will be setting a very low, if destructive, baseline for the price of renewable energy sources for a long, long time.
Coalgas is what you get when you break down coal to things like hydrogen and water and co. you can run anything on that gas. No need for a fuel cell.
Some drink at the fountain of knowledge. Others just gargle.
The fuel cells are also said to capture about half of the energy in the coal gas, as opposed to the third captured by burning.
and
Because solid oxide fuel cells have traditionally operated best at temperatures above 850C (1,562F), they have had to be made from relatively expensive heat-resistant materials. When treated with barium oxide and running on coal gas, however, they can operate at temperatures as low as 750C (1,382F).
How much energy does it take to gasify coal? - Deduct that. Also deduct the energy required to keep the fuel cell at 750C. Fuel cells currently run about 40% efficient, so multiple the previous number by 0.4. It's going to be a lot less than 30%.
Unlike hydrogen fuel cells, these ones do create carbon dioxide in the course of operation. Part of that CO2 is reused, however, for gasifying the coal. The rest is in a much more pure form than that produced simply by the burning of coal in a power plant, so extensive separation and purification wouldn't be required for sequestration.
So what CO2 sequestration are they envisaging? I'm not aware of anything that is truly commercial yet, except for the paper accounting job of claiming biomass production for a CO2 removal brownie point.
How much energy
A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort.
The point of a fuel cell would be to burn fossil fuels more efficiently.
Dog is my co-pilot.
than oil. Plus, using fuel cells to generate electricity is generally more fuel-wise efficient than trying to do it via combustion - so far , combined cycles (and there's few of those) have efficiencies between 50-60 % IIRC - in other words technology like this will make our stockpiles last *longer* not shorter.
I'd actually buy that, just to piss off the overbearing Greens movement of today and their insane and self-destructive attitude on power generation.
but, will it require that the coal be clean FIRST? If so that will be difficult. But if all it emits is CO2, and water, that is not that bad. This is then no different than running natural gas, so that at large plants, the CO2 can be directed into the ground.
I prefer the "u" in honour as it seems to be missing these days.
"in-" is a negative prefix.
I was going to mod you in-sightful ; but I doubt anyone would get the joke.
Are you in genius, in competent, in capable... - BB.
We cut the top off of mountains because it is cheaper not because "coal that we can get from a mine" is running out.
Whatever happened to just carbon fuel cells?
from 2005: http://www.newscientist.com/article/dn7891-coalpowered-fuel-cell-aims-for-efficiency.html
and some unknown date: https://www.llnl.gov/str/June01/Cooper.html
If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
This is nothing really new. Back in the Late 1970's and early 1980 I was part of a team at SRI international that used Bituminous coal as the fuel source for a molten Carbonate fuel cell that ran at near 500 deg C. The eutectic combination of Sodium Potassium and Lithium Carbonate would absorb the Sulfur, and ash content of the Bituminous coal. I found that series 300 stainless steal would form a very nice passivation layer as long as there was some oxygen around inside the fuel cell, so the cell could be contained in relatively cheap 316 steel. The molten carbonate would need to be cleaned every so often to remove the sulfur, and other solid ash from the coal. The output of the fuel cell was about 1.2 volts, and pure CO2. The only processing of the bituminous coal that was necessary was to solidify the bituminous coal into an electrode with a wire mesh of conductive wire that would not be corroded by the molten carbonate at 500 degree C. NO GASIFICATION WAS REQUIRED. from our experiments the fuel cell plant would have an overall efficiency of about 35 - 40% which is much higher than coal burning plants, plus all the sulfur, and ash would be contained in the molten carbonate rather tan spewed into the atmosphere. The project was killed when the Government deemed in the early 1980's that we were beyond the research stage, and the team at SRI international and EPRI could not find funding for a pilot plant operations. if you are interested in furthering this project, you just need to look for papers with the authrs of Robert Weaver, Steven Leach and/or Michael McKubre. There are papers in the EPRI archives, as SRI international reports and in the Journal of the Electrochemical Society.
The problem with Gasification is the SULFUR, and the FLY ASH from the coal. SULFUR KILLS Fuel cells that use most catalyst , and fly ash is the BIGGEST issue with coal burning plants. I wish this tam all the best in commercializing this process, but I also know that while this process will be more efficient than using steam conversion teh biggest issue will be the SULFUR and Fly ASH.
GOOD LUCK and may the US Government and the big power cartel treat you better than they treated our team.
Sorry about the self-reply, but let's clarify this a little more.
Cutting the top off of mountains to get to coal is the logical consequence of regulations in the United States and modern technology. Our government (arguably that means our society) values people more than it values the environment.
Shaft mining is risky, and it always will be. Mountaintop removal takes more machinery, more energy, but less people, and less risk. Machinery (technology) is cheap in the USA, as is energy. People, both in terms of labor cost and in terms of safety regulation cost, are expensive. It is no wonder we do it.
These guys are working on a new SOFC catalyst that will allow them to run gasified coal at lower temperatures without running into problems with coking. The basic idea is to gasify coal and then use internal reforming (a standard benefit of SOFC technology) to reform the hydrocarbons into CO and H2 which can be used directly as fuels. The new part is that this new catalyst is capable of running at lower temperatures without seeing a buildup of carbon, generally this is a problem that is solved by higher temperatures/power densities (which causes faster degradation) or more steam injection (more water needed).
The problem itself was the entire goal of the SECA program in the US because there is so much coal, and this gets better efficiency than just burning it normally. However, it looks like funding is on the way out for these programs, fossil fuel guys don't like fuel cells and vice versa. Most of the big players, GE, Siemens, etc have already bailed.
Some companies that use similar technology: Versa Power (US & Canada), Bloom Energy (US), Staxera (GE), Ceres Power (UK), CFCL (AU) and others
Coal won't run out, but we are definitely past "peak coal." Instead of hollowing out a mountainside, companies are force to use more risky/dangerous/environmentally devastating ways to get at the coal.
Oh, don't forget quality of coal. Lignite coal is very polluting. The good stuff, anthracite is effectively all gone, so no coal plant is going to be running it. Instead, the coal being used is bottom drawer stuff that either spews toxins in the air, or if filtered, ends up at the coal site.
There was a /. post a few weeks back of some innovative poster who managed to compute the total of deaths per terawatt caused by energy sources. Believe it or not, nuclear was dead last in confirmed kills, and coal was pretty high on the list.
The reason why coal is so common is that it is cheap and relatively plentiful. Even though it will turn areas into environmental nightmares [1]. Coal also has a large lobby behind it, while people will piss their shorts if they hear "nuclear", or "noo-clu-ear" like our last CIC.
Bottom line: We need to leave the dirty brown shit in the ground where it belongs and start splitting the atom for energy sources. Unless we want gas masks to go from a cool fashion statement for a date on a Saturday night to a necessity.
[1]: Compare the areas left by coal mine tailings to the area around Pripyat. One of which has plentiful flora and fauna running around. The other is just barren with only a few strains of bacteria existing.