Why introduce yet another expensive, energy-intensive and risky technology if there are so many other and better ways to solve the energy crisis? If we chose to build a completely new infrastructure of pipelines comparable to that of the existing oil and gas industry, why not build something like an extensive underground tubular freight network instead? This would be a real solution, which would considerably lower transport energy use and CO2-emissions.
Why not channel the huge amount of money needed for the development of CCS to countries with tropical rainforests, so that they have a very good reason to protect them fiercely? Stopping deforestation, especially in tropical forests, would contribute more to the fight against global warming than carbon capture technology could ever do. Tropical forests store enormous amounts of carbon and they are not prone to natural forest fires.
"Halting deforestation in tropical forests would contribute more to the fight against global warming than capture technology could ever do."
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"A 50 percent increase in energy consumption is the last thing that the world needs."
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Attractive idea
The idea of carbon capture and storage (CCS) – first introduced in the 1970s - is attractive at first sight. Capturing CO2 from smokestacks has been a common practice for many years, for the purification of natural gas or at ammonia production facilities for instance. Injection and storage of carbon dioxide is happening already in the
A complete CCS infrastructure has not been demonstrated yet (all CO2 used for enhanced oil recovery is commercially produced or originates from other sources than power plants, and present capture techniques do not capture CO2 for storage but emit the gas in the atmosphere). Yet, since all the individual parts exist, this does not seem to be an obstacle either.
Energy penalty
The problem at hand is that the process of capturing, transporting and storing carbon dioxide requires a vast amount of energy. If this energy were to be derived directly from fossil fuels the benefits of the CO2-savings by capture and storage will be offset by the very same energy intensive process. If the energy were to come from renewable sources the technology is rendered unnecessary as it would be much more efficient to generate electricity directly from the renewable source.
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"If fuel use of electricity generation rises by 50 percent, the same goes for air pollution from coal plants and for the ecological consequences of coal mining. Storing the CO2 does not solve that."
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Capturing CO2 from smokestacks is the most energy-intensive part of the process. According to the International Panel of Climate Change (IPCC), which devoted a comprehensive study on the technology 3 years ago, capturing technology (including compression for further transport and storage) raises the energy consumption of a coal plant by an average of 32 percent.
A coal plant equipped with CO2-capture technology would thus need 32 percent more coal and other resources like water, chemicals and reagents to produce the same amount of electricity than the same power plant without this technology.
Pipeline infrastructure
This 32 percent does not include the energy needed to mine, process and transport the many thousands of tonnes of extra coal, and it does not include the energy needed for the construction of the capture, transportation, storing and monitoring infrastructure either.
It is insufficient to simply place the smokestacks of a coal plant upside down as suitable underground reservoirs do not necessarily lie beneath the world's power stations. A carbon capture and storage infrastructure requires a transport infrastructure consisting of pipelines (and tankers) that rivals the existing oil and gas network.
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Manufacturing and installing these thousands of kilometres of stainless steel pipes will require a substantial amount of energy. Also, the transport by ship or pipeline itself requires energy, and so does the injection of the CO2 in underground reservoirs and the monitoring of the whole transport network (today’s pipelines are patrolled by plane every two weeks).
Everything taken together, CCS will probably raise energy consumption by as much as 50 percent.
There are losses during transport, too. According to the IPCC these are 1 to 2 percent per 1,000 kilometres of pipeline transport and 3 to 4 percent per 1,000 kilometres of ship transport (the ship's fuel use included). Carbon dioxide is also not the only harmful effect of power generation. Burning coal brings serious air pollution and produces waste, both of which will also rise by at least 30 percent. The same goes for the ecological damage of coal mining, which is devastating. Storing the CO2 can never prevent this.
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Turning CO2 in plastics
However, even though the amount of chemicals and plastics we produce is enormous, as a carbon sink they are all but meaningless.
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The Myth - "If all polycarbonates and polyurethane would be produced by means of CO2 this would only store the emissions of 3 coal power plants."
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According to the IPCC, producing all polycarbonates and polyurethane by means of carbon dioxide would store 3.3 million tons of CO2 – comparable to the annual emissions of just 3 coal power plants.
What makes this approach even more useless is that these consumer products and chemicals have a relatively short lifespan, from a few months for fertilizers to some decennia for plastic products. When the fertilizers are used, or when the DVD’s end up in the incinerator, the CO2 goes back into the atmosphere.
Burning algae
Using CO2 as a feedstock for algae and then turning it into biofuel - another idea that is hyped these days - faces the same problem. It only delays CO2-emissions for a very short time. The carbon dioxide is converted into fuel which is further burnt in a car engine.
It is impossible to capture CO2 from car engines since the gas is too heavy (your car would gain serious weight while driving, and it would have to pull a trailer to store the large volume of carbon dioxide).
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"Turning CO2 into algae could be an interesting strategy if we bury the algae instead of burning them in our car engines. However, that’s not on anyone’s mind."
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One could argue that at least the CO2 is recycled and that we are using the by-product of electricity generation to make fuel – which means that we don’t have to dig up more fossil fuels to make gasoline. However, this argument does not take into account the fact that much energy (and water) is lost in the conversion process.
Firstly, there is again the energy penalty of CO2 capture from the smokestacks, on average 30 percent. Next, you have to build a huge infrastructure to produce algae (since their energy efficiency is 100 times smaller than that of solar panels) and furthermore there is the energy that gets lost during the process of turning algae to fuel. If there is net energy gain in the end, it will be small.
Turning CO2 into algae could be an interesting strategy to reduce CO2-emissions if we store the algae underground instead of burning them in our car engines (thus avoiding the energy-intensive process of converting them into fuel). However, that’s not on anyone’s mind.
Atomic waste, meet your rival
Carbon capture technology is expected to become more energy-efficient in the future. But that would make the whole scheme hardly more attractive. Storing carbon dioxide in underground reservoirs (the only realistic option) is risky, not unlike the storing of atomic waste.
CO2 can escape. High concentrations of the gas are lethal to plants, animals and humans. Eventually the gas thins in the atmosphere but during escape concentrations can build up fast, especially since CO2 is denser than air. At concentrations above 2 percent in ambient air, carbon dioxide has a strong effect on respiration (the normal concentration in fresh air is 0.033 percent). At concentrations from 7 to 10 percent, it kills.
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"If CO2 escapes from storage reservoirs, the whole energy-intensive operation of capturing, transporting and storing it was all for nothing."
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Small impurities in the gas make it lethal at even lower concentrations. Similar amounts in the soil kill vegetation and make groundwater unsuitable for drinking or irrigation. And of course, if CO2 escapes from storage reservoirs, the whole operation of capturing, transporting and storing it was all for nothing. The result is a considerable rise in emissions, because of the energy penalty involved (the energy use of the whole process can go down, but it will never come close to zero).
Real solutions, please
Why not put into force a regulation that prohibits the construction of any more power plants that burn non-renewable energy sources? There is already an enormous energy capacity in the world, why don’t we chose to do it with the energy plants that we have? This would at last make energy efficiency useful (because progress in energy efficiency is now always again nullified by new and more energy hungry products and services). Still want more energy? Build a solar plant or plant a windmill.
These are just 3 ideas that would be effective without the need to adapt our lifestyle (which is, of course, also the attraction of "clean coal"). They would not solve everything, but at least they would be very welcome steps into the right direction, the direction of a solution.