What would you say if I would tell you that a power plant with zero emissions is possible? Probably, your answer is: cool, let’s do them! But what if I would say, that a power plant with negative emissions is possible? Then I see two possible scenarios. One would be you screaming ”are you mad!?” and the other would be ”what does this even mean?”. The negative emissions power plant means, that there is literally a power plant, that is not producing any CO2. Moreover, it is a power plant, that is capable of storing the carbon somewhere safe and out of reach.
What is carbon and why is it so bad for us?
Carbon itself is not harmful and is an element that builds almost everything that we know (both organic and inorganic matter). In nature, it is present in solid (diamonds, trees, our bodies etc.) and gas (CO2, CH4, etc.) form. So why do we keep hearing about this bad boy and why do we want to put it away so badly?
First, let’s look at the carbon in solid form. This is the one we want to have more of. In this form, the element is just sitting there and patiently waiting to be released, without having any influence on the outer world. Releasing is done by thawing, burning, *degradation and decomposition processes.
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Everything degrades but it does so on different time scales. For example, we say ”diamonds are forever”, which is only true from the perspective of our lifetime. If we look at this from a larger timescale, we would learn that they do degrade. They degrade in about a billion years, and the end product is graphite (the gray thingies we have in our pencils).
Remember how I said, having the solid things in our lives is a good thing? I will change my definition and say – having big solid things is a good thing. I am referring to the problem of the particles, that are being released during the fires (wildfires, burning the agricultural land, burning fossil fuels, etc.), and are also released by factories and car exhaustion system. These particles can affect our health (cause lung diseases) as well as the health of an ecosystem. The latter is done by their contribution to global warming, speeding up the thawing process, and changing the water cycle. The sun warms up the particles, and because they have too much energy, they release it into the surrounding environment, increasing its temperature. The same happens, when these particles are lying on top of the snow cover. They release the energy, which contributes to speeding up of the thawing process. Because of changed thawing cycles, the whole water cycle (and sometimes also the whole life cycle) in the area changes. But the problems with small particles up in the sky don’t end here yet! They can also change the water cycle by being there for the water vapor. Water vapor can only start the condensation cycle when it finds the condensation core. The tiny drops are not very picky and are happy to find just about anything solid (a dust particle, virus, spore etc.). More present particles mean more condensation cores which leads to changes in the amount of precipitation as well as its patterns. These changes can change the cycles and therefore affect the health of an ecosystem.
Related article: Making broad lands leads to desertification
What about the carbon in form of gas? I would like to point your attention to two of them – carbon dioxide (CO2) and methane (CH4). These two gases are in the group called the greenhouse gases. I know, I know, this group has a negative ring to it, but actually, these gases are not really bad if they are balanced (water vapor is also in this group!). With this name, we simply name all the gases that are present in our atmosphere and emit or absorb the radiation from the sun. As a matter of fact, they help to balance the atmosphere as it is and without them, we would not be where (and how) we are today.
Both of referred gases have natural sources and natural sinks. The natural source of CO2, for example, is respiration ((or breathing) of soil, animals, and plants), decomposition processes, wildfires and volcanic eruptions etc. The natural sources of methane (CH4) are wetlands, metabolism of microorganisms, thawing permafrost, etc. The biggest natural sink for carbon is the ocean itself, but the fossil fuels, ocean sediments, and soil contribute a lot as well. Here you can find a simplified global carbon cycle.
So why do we find carbon problematic?
Because we have made many changes to the environment after the start of an Industrial Revolution in the second half of the 18th century and many of them contributed to increasing concentrations of CO2. With these changes, we have crushed the balance of all the components in the environment, and therefore affected many processes. Besides the things we do that I already mentioned, there is one more thing I can’t pass by without stumbling over – and this is livestock. We would like to have enough food to feed the growing global population and for this, we increased numbers of livestock. Unfortunately, they are a great source of carbon emissions, but their contribution differs between livestock species). Ecosystems globally have been trying to adapt to these new conditions of rising carbon levels, but the evolution is just too slow to keep up.
The additional problem is also presented by the rising global temperature (rising carbon levels are to blame for this too). The rising temperature of the air is affecting the temperature of oceans and other ecosystems (permafrost, for example). With changed temperature, living conditions as well as capability to store carbon and other abiotic factors change. Scientists estimate, that there are about 38 000 billion tons of carbon stored in oceans, which is about 16 times more than in all of the terrestrial ecosystems. They also estimate, that about 1,8 trillion tons of carbon are stored in the permafrost (which is twice the amount of carbon, that is currently suspended in Earth’s atmosphere!). So, as you see, the numbers are quite high and I don’t even want to begin to imagine what releasing all of this carbon would mean for our pretty little planet.
Do you now see, why I was so excited about the powerplant with negative emissions?
A company called Climeworks has turned on the first power plant of this kind in Iceland in October 2017. The whole mechanism actually works on a very simple idea. The air, that has high concentrations of CO2 (read, all air) is put through a filter. The filter removes the carbon from the air and releases it right back where it came from (not really affecting the overall CO2 concentration at the moment).
The filtrated carbon is then being bound together with water inside of the power plant. With this process, the carbonate minerals, that are the key step in this process, are produced. These minerals are being disposed deep into the ground and will sit there until it will be released again (after about a million years).
Of course, one power plant of this type is not enough to stand up to the pollution problem. However, building the whole army of them could be the first step in fighting climate change and ecosystem protection!