Archive for January, 2010

Natural Gas + Fuel Cell (SOFC) – Cheapest Route to Cleaner Electricity?

Posted by on Tuesday, 26 January, 2010

Two researchers at MIT say they have what will be “the lowest price option” for power generation in the future if a carbon tax of about $10 per T of emitted CO2. (Source)

The duo – Thomas Adams and Paul Barton – have proposed a novel electricity generation process that combines natural gas and solid oxide fuel cells.

While the researchers claim that their idea could work also with pulverized coal, they feel using it for natuarl gas will produce the best results.

Their process contains a steam reformer that prepares the gas for use within the fuel cells. The reformer and water-gas shift reactor creates a fuel mix absent CO, thus avoiding the problems created by carbon deposition issues in SOFCs when CO is present. The CO2 that is generated will be “mostly pure”, according to the researchers and they also claim that it can be captured with very little energy penalty.

Simulation of their system has indicated that the lifecycle cost of this novel system is lower than that of a combined-cycle natural gas plant, even without carbon pricing. They say that even with a carbon tax around $5 to $10 per ton, their system would be cheaper than coal plants.

Now, the cost part of it we can safely ignore whatever the researchers say because real life is very different from lab simulations. But if the technology works smoothly, it could be great. As you will know, natural gas based power production emits much less CO2 per MWh when compared to coal and if the CO2 capture becomes cheaper and easier using an SOFC fuel cell with natural gas, so much the better!

Well, the one question is “what happens to the 50,000 power plants already existing?” Guess it is far fetched to assume that they will be delighted to shift fuel cell based power production from the current steam – turbine cycle they predominantly use. And imagine the capital costs for such migration.

The idea, if it works smooth and is techno-and-economically better off than other CCS ideas, could well get those developing new power plants mighty interested.

Fuel Cell


Capturing CO2 Using Copper at High Electric Potential

Posted by on Monday, 25 January, 2010

In the entire carbon capture and storage process chain, the stage that is most costly is the carbon capture part. Some studies estimate that the capture portion alone would contribute over 75% of the total cost.

Thus, it is no surprise that many scientists and engineers are keen on finding innovative ways to cut down the costs of CO2 capture.

A group of scientists has now found a copper complex that is capable of reacting with carbon dioxide at a slightly elevated electric potential. The process turns the carbon dioxide into a usable byproduct which can be recycled and reused for this purpose multiple times.

An easy way to get carbon dioxide out of the atmosphere is to find a chemical that combines easily with it, similar to the way that some metals oxidize. Unlike oxygen however, CO2 cannot combine so easily with other materials.

This group of scientists appear to have found an interesting solution: They found a certain dinuclear copper (I) complex that turns green when exposed to air under a slight electric potential (-0.03 volts), owing to the reaction with carbon dioxide and “capturing” it.

The result of the reaction was a tetranulcear copper complex with two oxalate groups. To minimize the wastage of copper, the researchers found that they could wash the oxalate from the copper complex. After this process was complete, the copper complex was returned to its original state and was ready to react with more carbon dioxide.

But wait. All these are working OK at lab level, but apparently they work way too slowly for any commercial use.

I guess this is at a pure research stage right now, and unless I see more efficient and speedy processes in this context, I guess these types of ideas will remain at the lab stages for much longer.

Via


Enzyme-based Capture Carbon – CO2 CCS Idea from Blood

Posted by on Monday, 25 January, 2010

Read an interesting article on how United Technologies is mimicking a blood enzyme to capture carbon from coal plants.

OK, this doesn’t sound like something that could be implemented within the next many, many years, but it is an interesting idea all the same.

We all know that our blood cells constantly capture CO2 and move it someplace better. This is quite analogous to what coal-fired power plant operators may want to do with all the carbon dioxide at their power plants.

Using this analogy as the base, scientists at United Technologies’ research center are trying to develop industrial blood–a synthetic version of the enzyme that blood uses to capture CO2.

The scientists envision a simpler, cheaper system involving membranes that sift carbon dioxide out of the flue gas. By doping the membrane with a substance based on the enzyme that blood uses to capture CO2, called carbonic anhydrase, the team hopes to facilitate precise carbon catpure.

Carbonic anhydrase, found in red blood cells, grabs the CO2 and transforms it into a bicarbonate ion and a proton, which dissolves easily in the blood and can then be carried away to the lungs. In the lungs the enzyme does the opposite: it changes the bicarbonate back into CO2 so it can be breathed out.

Interesting analogy.

There’s more about it here, so those who wish to understand the science better are requested to read it. Me, I would like to be more practical. What is the chance that such a technology would ever come out of the labs and into the commercial space? And if it indeed does, how long would that take? And the evergreen billion dollar question – how much would that cost?


CCS Breakthrough – Coal Gasification + Fuel Cells is the Future?

Posted by on Monday, 25 January, 2010

Of late, I have been hearing a lot on the virtues of coal gasification combined with fuel cells as a method for carbon capture. It is called “clean coal” by some.

The idea is fairly simple. Gasifying coal results in syngas – a mixture of CO and H2. When you mix this syngas with steam, the CO gets oxidized to CO2. Thus, you have a gaseous mixture of CO2 and H2. The idea is to separate the CO2 at this stage and send in only the energy carrier hydrogen in fuel cells to produce power. The result of such a process is pure distilled water. (A 1,000 MW power station they would produce over 2.5 billion liters of clean water a year, according to some estimates).

Thus, you have separated CO2 at (reportedly) low costs, and have an environmentally sound combustion that produces only pure water, which is valuable in itself!

As per this article, Australian clean coal tech firm Linc Energy and British fuel cell specialist AFC Energy are the latest to predict that coal gasification and fuel cell combination could revolutionize power production.

These two have signed a major new partnerhip which, it is hoped, will culminate in a demonstration project sometime in future. Under the alliance, Linc has been granted exclusive rights to test AFC’s fuel cell technology in conjunction with underground coal gasification techniques.

It is too early to sing the praises of this combo process because the cost components are still not known. But, with over 80% of the cost of CCS is incurred in the CO2 capture stage, the new process could potentially offer a cheaper alternative whereby the CO2 is already captured and contained, ready for injection into its storage area.

Fuel Cell


CO2 to Limestone Using Basalt Formations – Capture, Storage

Posted by on Saturday, 23 January, 2010

Was reading an article on carbon sequestration that has a focus on basalt rock formations on the coasts of New York, New Jersey and Massachusetts.

Add this a recent Popular Mechanics article comments on the potential for these rock formations to be the storage place for CO2. It says, “…a new scientific analysis suggests /that the related basalt formations buried under the U.S. East Coast and extending out to sea might someday be doing some critical trapping after all — of greenhouse gas emissions from the likes of giant coal-burning power plants.”

Basalt is capable of transforming CO2 dissolved in water into calcium carbonate, or limestone. This way, CO2 is stored in the form of stable carbonates for a very long period.

Results of the analysis published in a recent edition of The Proceedings of National Academy of Sciences suggest that the basalt formations actually may be ideal for capturing billions of tons of CO2, with single basalt formations alone having the potential to capture almost a billion T.

That’s not a bad number at all. The world emits something about 35 billion T of CO2 per year, and the world will be keen to capture at least 10 billion T of these every year. If one basalt formation could store a billion T, with a large number of such formations world over, the potential could be sizable for the medium term. However, the worldwide capacity estimates for these basaltic rock formations that can store CO2 appear to be quite preliminary in nature.

This site gives the cost of storage alone at about $10 per T of CO2. However, this does not include cost of capture and transportation.

In terms of actual work on the ground, two such projects appear to have done some amount of work – the “Big Sky Carbon Sequestration Partnership,” headed by a team including researchers from Idaho National Laboratory, the University of Idaho, Boise State University, Idaho State University, (Hickey), and “Carbfix,” a project in Iceland run by a team from the University of Iceland, Columbia University, Centre national de la recherche scientifique, and Reykjavik Energy (CarbFix). (Source)

Guess just projects being out there does not augur too well for this area, but again, CCS efforts themselves are only about a decade old, so it will interesting to watch out the developments in the domain of basalt storage of CO2.


Five New Carbon Capture Research Projects – Novel CCS Ideas

Posted by on Saturday, 16 January, 2010

Here are five interesting carbon capture research projects mentioned at Advanced Research Projects Agency – Energy (ARPA-E) (US department of energy): (Source page)

CO2 Capture with Enzyme Synthetic Analogue

United Technologies Research Center (UTRC) (East Hartford, CT) will develop membrane technology for separating CO2 from flue gas streams using synthetic forms of carbonic anhydrase, (CA), which natural systems use to manage CO2.

Pilot Scale Testing of Carbon Negative, Product Flexible Syngas Chemical Looping

A novel process known as Syngas Chemical Looping (SCL), in which coal and biomass are converted to electricity and CO2 is efficiently captured, has been successfully demonstrated on a laboratory scale. In this project, the SCL process, will be scaled up to a 250 kW pilot plant for a planned demonstration at the National Carbon Capture Center.

Carbon Nanotube Membranes for Energy-Efficient Carbon Sequestration

Porifera, Inc., (Hayward, CA) Inc will lead a team including the University of California, Berkeley and Lawrence Livermore National Laboratory that will integrate carbon nanotubes with polymer membranes to increase the flux of CO2 capture membranes by up to 100x. Physical and chemical modifications to the carbon nanotubes will be used to increase the selectivity of the membrane for CO2.

Energy Efficient Capture of CO2 from Coal Flue Gas

Nalco Company (Naperville, IL) and will partner with Argonne National Laboratory and the Western Research Institute have partnered to develop an electrochemical process for CO2 capture. A technique known as Resin-Wafer Electrodeionization (RW-EDI) leverages control of pH to adsorb and desorb CO2 from flue gas without the need for heating or a vacuum. The objective is to drastically reduce the current parasitic power loss of 30% that is currently associated with carbon capture from flue gas.

Electric Field Swing Adsorption for Carbon Capture Applications

Scientists at Lehigh University (Bethlehem, PA) will seek to develop a novel carbon capture technique based upon Electric Field Swing Adsorption (EFSA), is a technique that takes advantage of the ability of electric fields to change the interaction of molecules on a surface. In this project, EFSA will be applied to high surface area conductive solid carbon sorbents for the adsorption and desorption of CO2 across a wide range of process conditions. The EFSA technique has the potential for drastically reduced parasitic load compared with current carbon capture methodologies.

Ok, some of the core themes for the above five:
1. Biomimicry
2. More efficient membranes
3. Using electrochemical processes to make CO2 capture more efficient
4. Using electric fields to modify material properties resulting in better adsorption and desorption.

Interesting. The key question is of course, when will these be anywhere near commercially viable, because most of these innovative ideas appear to be pretty much in the lab stages.


CO2 to Bioplastics, Biochemicals Using Microorganisms – RWE, BRAIN Partnership

Posted by on Saturday, 16 January, 2010

At my company, we had been doing a good amount of work last six months to understand the latest efforts and innovations being attempted in sequestering CO2 from power plant emissions.

One of the areas we had been doing research was in converting the CO2 into useful products that have market values. This concept is exciting for two reasons: (1) It is a novel method of CO2 capture, and (2) It can make the entire CO2 sequestration efforts more sustainable.

I must admit that the findings of our research were not all together positive. Our preliminary conclusion was that, outside of using it for cement making, there are few products that can utilize exhaust CO2 in a sustainable and scalable manner in order to make any meaningful difference to the global CO2 mitigation efforts. Using CO2 for plastics appeared to be an exciting area, but we figured that neither the technical nor the economic feasibility was anywhere close to being clear.

Our research was only a preliminary research, and we plan to resume the research from where we left in a couple of weeks. In the meantime, this press release caught my eyes “RWE Power, BRAIN Join Forces in White Biotech: Co-Operation on CO2 as Raw Material for New Products”. Naturally, I was excited to know more about it.

Well, this is the essence of the press release:”To convert carbon dioxide into microbial biomass or biomolecules: such is the goal of co-operative research agreed between RWE Power and BRAIN AG from Zwingenberg. The power generator and the biotech company want to equip micro-organisms” with new enzymes and explore innovative synthesis-routes and pathways. Flue gas, rich in CO2 from a lignite-fired power station, feeds these designer micro-organisms. The process creates biomass and industrial products such as new biomaterials, bioplastics and chemical by-products. Possible applications, now being explored, include building and isolation materials and the production of fine and specialty chemicals. An experimental plant is to be located at RWE Power’s Coal Innovation Centre, at its Niederaussem power plant site.”

OK, so the folks are trying to use designer micro-organisms and figure out if they could arrive at useful end products as a result. This is not exactly unheard of – during our research, we had come across a few companies that were attempting to produce products from CO2 using microbes and biotech pathways, but most of them were small labs and universities, or small companies. So it is good to know that some large companies are making some efforts in this domain as well.

RWE is a well-known power company which also has been pioneering quite a few CCS efforts. But I knew little about B.R.A.I.N (oh well, that’s the way the company represent themselves!). Here’s something more about them – http://www.brain-biotech.de/en/about.html . An European biotech company, they appear to have been more focussed on chemicals, food and pharma industries thus far, with their biocatalysts, enzymes and other bio-based intermediaries. The GHG abatement industry must be a new one for them.

It is with some disappointment that I saw that there were few insights into what the companies actually planned to poduce in terms of end products. Will be keenly watching their updates.


Using Rust in Oxy-fuel Combustion in Coal Power Plants

Posted by on Wednesday, 13 January, 2010

Oxy-combustion is one of the potential methods explored for carbon capture and storage. Within this, a number of materials are being explored to capture the oxygen from the air so that pure oxygen is supplied for combustion. The latest material being tried in this context is iron, which converts to iron oxide – rust – upon oxygen capture.

This experiment is being conducted by researchers at Ohio State University, and has the potential to reduce the costs of oxy-fuel combustion.

Most coal-fired power plants burn pulverized coal in air, and since air is mostly nitrogen, so is the exhaust emissions–only about 14 percent is carbon dioxide. This process called chemical looping produces a highly concentrated stream of carbon dioxide. Such a stream would be easier to capture than a stream that has CO2 in dilute amounts.

With chemical looping, coal isn’t exposed directly to air. Instead, it involves a series of chemical reactions in which a solid material first captures oxygen from the air and then transfers it to the fuel – without the nitrogen or other gases in air. Thus there is little or no nitrogen present in exhaust stream, making CO2 capture a far easier process.

In the experiment conducted, iron is used as the intermediate material that captures oxygen from the air, and forms iron oxide. When this iron oxide is reacted with syngas formed from coal gasification, oxygen is released and iron oxide is converted to metallic iron which is again used for capture of oxygen from air. The oxygen oxidizes the carbon monoxide and hydrogen, forming steam and CO2. The steam can easily be removed by condensing it, leaving behind highly concentrated carbon dioxide that can be captured and stored.

Source


A “Slow” Gasifier for IGCC Uses Low Quality Coal

Posted by on Wednesday, 13 January, 2010

Here’s an interesting variation of the gasification technology that is able to utilize low-quality coal for gasification-based (IGCC) power plants. (Source: Technology Review)

This will soon be tried at a coal-power plant in the industrial boomtown of Dongguan in southeast China’s Pearl River Delta. Its developers, Atlanta-based utility Southern Company and Houston-based engineering firm KBR, announced the licensing deal with Dongguan Power and Chemical Company this month.

This technology uses a transport gasifier to turn cheap, low-quality coal per hour into a clean-burning gas. Conventional gasifiers have temperatures around 1,500 ºC. Such high temps, melt ash and other mineral contaminants in the coal, forming a glassy slag that eventually damages the reactors.

Dongguan’s gasifier will sidestep those issues by operating at just 925 ºC to 980 ºC, below the contaminant melting temperature. Coal nevertheless gasifies completely at these lower temperatures. How? Because it spends twice as long in the new process. Looks like a simple adaptation!

The specific technology is an adaptation of the fluidized catalytic cracking.

The technology is attractive to Dongguan Power because it can use coal that is cheaper and less desirable.


Costs of CCS in 2100? – Carbon Capture Capital Cost Reductions

Posted by on Tuesday, 12 January, 2010

While I was doing some browsing with the question in title lurking in my mind (What Will be the Costs of CCS in 2100?), I came across the following:

“The more I have thought about these issues, the more I have become convinced that carbon capture is going to end up being the centerpiece of long-term geoengineering solutions. There are good reasons to be optimistic that in 50 to 100 years we will be able to remove carbon dioxide from the air for one-thousandth or one-millionth the current costs.” So writes Steven Levitt in his blog at NYTimes.

One thousandth or one millionth of the current costs? That sounds too outlandish. Well, OK, everyone gives the analogy of the computing industry and Moore’s Law, and so does Steve. But I doubt Moore’s Law can be applied to every technology possible. If that were true, solar PV will today be costing far, far less than what it is costing. In the last 30 years or so, solar PV capital costs have fallen to one tenth of their original, but application of Moore’s Law suggests a far, far larger decrease.

I think it will be more useful to identify those parts of CCS capital costs (and operational costs) that have significant potential for disruptive innovations. These cost components will have potential for such enormous decreases in costs or increases in performance. I’m not sure if the CCS technologies that are being pursued today indeed have such “disruptively innovatable” components