Carbon Dioxide Capture Technology.

Carbon Dioxide Capture Technology.

RWE Npower, the UK’s largest electricity supplier announced plans to design and build the first Carbon Dioxide Capture pilot plant at a UK coal power station (Aberthaw South Wales). The first phase could be fully operational by 2010.

I feel that this has personal relevance to me, as this was the electricity company that I used at my old home, also that the local power plant which again is near where I live (Didcot) could have the opportunity to have one of these installed there too, if the technology passes its trial period at the Aberthaw plant. I also feel that personally this technology (if it works) would help to change Britain’s huge un-renewable energy consumption, and thus help to prevent more damage to the planet and maybe reach a point where we can near a sustainable environment.

Current Power Situation
Currently Britain is undergoing a huge push to become “greener” in terms of power generation. As it stands there are currently 18 electricity providers in the UK, Some of which include British Gas, Npower and Southern Electric, all whom have different means of providing electricity to the nation. As it Stands %20.5 of all the UK’s Power comes from Nuclear, 38.5% from Gas, 1.4% oil, 34% from coal only 1.25% from Hydro and 0.75% from Wind power, with a remaining 3.6% on other methods such as biofules, this all entails to a 9,000MW energy production. As you can tell from these figures, the country is no way near becoming “green”

Npower

As Described from their website, they are “We are the retail arm of RWE Npower, a leading integrated UK energy supplier, part of the RWE Group. RWE Npower operates and manages flexible, low-cost coal, oil and gas-fired power stations and are developing innovative energy-related technologies.”(http://www.npower.com/web/about_npower/index.htm)
As it stands, this is Npower’s current Energy Production

Coal Natural Gas Nuclear Renewable Other
46% 35% 13% 3% 3%

From these figures alone you can see that they are close to the 10% production of renewable power that the government has set to all electricity companies to be achieved by the year 2010 which ties in nicely with their aim of completing the first working generator by 2010

How it Works.

Carbon capture is useless on its own, the real principles of it lie in the storage of this captured CO2

The CO2 is captured in 2 main ways

In “oxyfuel” combustion referred to as "zero emission", pure oxygen is burned instead of air. This produces a flue gas consisting only carbon dioxide and water vapour, which is cooled and condensed. The result is an almost pure carbon dioxide stream that can be transported to the sequestration site and stored. The technique is promising, but the initial air separation steps demands a lot of energy.
Post-combustion, the CO2 is removed after combustion of the fuel - this is the scheme that is active in current power plants. Carbon dioxide is then captured from flue gases (in the example of coal, it is sometimes known as "clean coal"). The technology is well understood and is currently used in places such as Didcot power station.
The main cost for the post combustion is from the excess energy required to run the plant, an extra %10-%40 is estimated, with a %30-%60 increase in other area’s dependant upon the circumstances of the plant (http://en.wikipedia.org/wiki/Carbon_capture_and_storage)
Storage – Commonly known as geo-sequestration this involves injecting the collected gas into underground Oil fields, gas fields, saline formations, unminable coal seams, and saline-filled basalt formations have been suggested as storage sites. Here, various physical (e.g., highly impermeable caprock) and geochemical trapping mechanisms would prevent the CO2 from escaping to the surface.
For well selected, designed and managed geological storage sites, IPCC estimates that CO2 could be trapped for millions of years, and the sites are likely to hold over 99% of the injected CO2 over 1,000 years.
Another proposed method of storage is in the oceans. Two main ideas circulate, The dissolution type involves injecting CO2 by boat or pipeline into the water at depths of 1000 m or more, and the CO2 then dissolves.
The lake type deposits CO2 directly onto the sea floor at depths greater than 3000 m, where CO2 is denser than water and is expected to form a lake that would decrease release of CO2 into the environment.
A third concept is to convert the CO2 to bicarbonates (using limestone) or hydrates.
The environmental effects of ocean storage are generally negative, but poorly understood. Large concentrations of CO2 kills ocean organisms, but another problem is that dissolved CO2 would eventually equilibrate with the atmosphere, so the storage would not be permanent. Also, as part of the CO2 reacts with the water to form carbonic acid, H2CO3, the acidity of the ocean water increases.
The time it takes water in the deeper oceans to circulate to the surface has been estimated to be on the order of 1600 years, varying upon currents and other changing conditions. Costs for deep ocean disposal of liquid CO2 are estimated at 40-80USD/ton. (2002 USD)
In conclusion, I find this method of dealing with the rising CO2 emissions to be one of the most intriguing and intuitive of the other technologies that I researched, and for this reason I will continue to find more information about this technology, to do so I will be looking at their main website:
www.RWE.com for the latest news about the company itself, and the project

I will also attempt to contact the company and ask them a series of questions about the project, and its usefulness, such as

-How much do you think this will cut down your emissions on the south western plant by?
-Will this be implemented in more, if not all stations if the test period is positive?
-What are the chances of extreme leakage from storage areas

Sources:

-http://www.rwe.com/generator.aspx/presse/language=en/id=76864?pmid=4001863
Main Article
-http://en.wikipedia.org/wiki/Carbon_capture_and_storage
Source of CCS details
-http://www.npower.com/web/about_npower/index.htm
Details about Npower

As Described from their website, they are “We are the retail arm of RWE Npower, a leading integrated UK energy supplier, part of the RWE Group. RWE Npower operates and manages flexible, low-cost coal, oil and gas-fired power stations and are developing innovative energy-related technologies.”(http://www.npower.com/web/about_npower/index.htm)
As it stands, this is Npower’s current Energy Production

Coal Natural Gas Nuclear Renewable Other
46% 35% 13% 3% 3%

From these figures alone you can see that they are close to the 10% production of renewable power that the government has set to all electricity companies to be achieved by the year 2010 which ties in nicely with their aim of completing the first working generator by 2010

How it Works.

Carbon capture is useless on its own, the real principles of it lie in the storage of this captured CO2

The CO2 is captured in 3 different ways

The main cost of it from the excess energy required to run the plant, an extra %10-%40 is estimated, with a %30-%60 increase in other area’s dependant upon the circumstances of the plant (http://en.wikipedia.org/wiki/Carbon_capture_and_storage)

“Geological storage in saline formations or depleted oil or gas fields typically cost 0,5 - 8 US$ per tonne of CO2 injected, plus an additional 0,1 - 0,3 US$” (http://en.wikipedia.org/wiki/Carbon_capture_and_storage