What Is Carbon Squestration?
Carbon sequestration refers to the process of capturing carbon dioxide (CO2) from the atmosphere and storing it in natural or human-made reservoirs to mitigate climate change. The goal of carbon sequestration is to remove carbon dioxide from the atmosphere, which can help slow down or reverse the negative effects of global warming.
Carbon can be sequestered in several ways, such as through planting trees, restoring forests, or changing agricultural practices to increase soil carbon storage. Other methods include carbon capture and storage, which involves capturing carbon dioxide from large point sources such as power plants or industrial facilities and storing it in underground geologic formations or other storage reservoirs.
Carbon sequestration is essential to mitigating the effects of climate change, as it helps to reduce the amount of greenhouse gases in the atmosphere, which contribute to global warming. It is one of many strategies that can be used to reduce carbon emissions and transition to a more sustainable future. However, it is important to note that carbon sequestration is not a silver bullet and must be used in conjunction with other strategies to reduce greenhouse gas emissions, such as transitioning to renewable energy sources and increasing energy efficiency.
Methods Of Carbon Sequestration
- Afforestation and Reforestation: Planting trees or restoring forests is a natural and effective way to capture carbon from the atmosphere. Trees absorb carbon dioxide through photosynthesis and store it in their biomass and the soil.
- Agricultural soil management: Certain agricultural practices such as reducing tillage, adding organic matter to soil, and using cover crops can increase the amount of carbon stored in the soil.
- Carbon capture and storage: Carbon capture and storage (CCS) involves capturing carbon dioxide from large point sources, such as power plants or industrial facilities, and storing it in underground geologic formations or other storage reservoirs.
- Bioenergy with Carbon Capture and Storage (BECCS): BECCS is a technology that involves capturing carbon dioxide from bioenergy production and storing it in underground reservoirs, effectively removing carbon dioxide from the atmosphere.
- Ocean Sequestration: Some ocean fertilization techniques aim to increase the growth of algae, which absorb carbon dioxide from the atmosphere. Carbon can then be stored in the ocean by sinking dead algae to the ocean floor.
While these methods have the potential to capture and store significant amounts of carbon, each has its benefits and drawbacks, and no single method can fully mitigate climate change. Therefore, a combination of these methods, along with reducing greenhouse gas emissions, is necessary to achieve a sustainable future.
How Does A Tree Capture Carbon?
The processes of photosynthesis and respiration capture carbon and release oxygen from the leaves of a tree. This occurs mostly at night when tree leaves pull moisture and carbon dioxide from the surrounding air.
Specifically, the leaves of a tree have tiny pores called stomata, which allow them to take in carbon dioxide. The carbon dioxide then combines with water that the tree absorbs through its roots to create glucose, which the tree uses as food to grow and develop. As the tree grows, it stores carbon in its wood, roots, and leaves, effectively removing carbon from the atmosphere and storing it in the tree's biomass.
How Much Carbon Does A Tree Capture?
Mature forests do not capture extra CO2. There is a balance between capture (growth) and release (decay). Young, growing forests, which include forest plantations, capture more CO2. Because trees lose leaves and branches, part of the captured carbon is released during growth. However, the majority remains sequestered in the trees.
Depending on age, climate, type of forest and soil, an acre of trees on average captures a ton of CO2 each year.
The problem of global warming is so immediate, governments around the world offer carbon credits to offset CO2 emissions, not just from burning forests but from polluting industries as well.
Carbon Capture
What Is A Carbon Credit
A Carbon credit (often called a carbon offset or tax credit) is a government issued environmental credit for greenhouse emissions reduced or removed from the atmosphere from an emission reduction project, which can be used by governments, industry or private individuals to compensate for the emissions they are generating.
Carbon credits are typically measured in tons of CO2-equivalents (or CO2e) and are bought and sold through international brokers, online retailers and various trading platforms. Businesses that find it hard to comply with the carbon emissions, purchase carbon credits to offset their emissions and reduce their taxes by making finance readily available to renewable energy projects, forest protection and reforestation projects around the world. These renewable energy and energy efficiency projects replace fossil fuel and polluting industrial processes. Their value depends on how much carbon a tree captures growing within a particular plantation.
Governments, organizations and industry invest in renewable forest projects around the world. In this way they are combatting climate change and generating short-term income before timber harvest. Because of this, an entire financial industry has grown around tradable carbon credits. Here are a few examples of carbon credit exchanges:
- European Union Emissions Trading System (EU ETS): The EU ETS is the world's largest carbon market, covering more than 11,000 power stations and industrial plants in 31 countries. The EU ETS allows companies to trade carbon allowances, which can be used to emit a certain amount of CO2. Companies that emit less CO2 than their allowances can sell their surplus allowances to other companies on the market.
- California Cap-and-Trade Program: California's cap-and-trade program is the largest in the United States, covering around 450 businesses and facilities that emit greenhouse gases. Under the program, companies must hold enough allowances to cover their emissions or face penalties. Companies can also buy and sell allowances on the market, which creates a financial incentive for reducing emissions.
- Chicago Climate Exchange (CCX): The CCX was the first voluntary, legally binding carbon credit trading system in North America. It operated from 2003 to 2010 and allowed companies to offset their emissions by investing in clean energy projects or purchasing carbon credits from other members of the exchange.
- Bioenergy with Carbon Capture and Storage (BECCS): BECCS is a technology that involves capturing carbon dioxide from bioenergy production and storing it in underground reservoirs, effectively removing carbon dioxide from the atmosphere.
- Gold Standard: The Gold Standard is a certification scheme for carbon offset projects that meet rigorous standards for environmental integrity, sustainable development, and stakeholder consultation. Carbon credits from Gold Standard-certified projects can be traded on the voluntary carbon market.
Green Bonds - Private Sector Carbon Capture Programs
Green bonds were created to fund projects that have positive environmental and/or climate benefits. Most green bonds issued are green “use of proceeds” or asset-linked bonds. Proceeds from these bonds are earmarked for green projects and backed by the issuer’s entire balance sheet. There have also been green "use of proceeds" revenue bonds, green project bonds and green securitized bonds.
Green bonds come with tax incentives such as tax exemption and tax credits, making them a more attractive investment compared to a comparable taxable bond. This provides a monetary incentive to tackle prominent social issues such as climate change and a growing movement to renewable sources of energy. To qualify for green bond status, the bonds are typically verified by a third party such as the Climate Bond Standard Board, which certifies that the bond will fund projects that include benefits to the environment.
Green bonds may be essential to confronting climate change. Green bonds are providing green investment opportunities for an ever-wider investor group, including those who wish to divest and diversify from fossil fuel-intensive portfolios.
The World Bank is a major issuer of green bonds, particularly for projects in the United States. We are currently creating a green bond for a diversified tree plantation project in the Pacific Northwest. The coupon value will depend on how much carbon each tree captures year to year in the project.
Carbon Capture Storage
Carbon capture and storage (CCS) is a means of mitigating the contribution of fossil fuel emissions to global climate change. It is based on capturing carbon dioxide (CO2) from large point sources such as fossil fuel power plants and storing it away from atmosphere by different means including sequestration. Carbon is an element present in Carbon Dioxide (CO2), which exists molecularly as one part carbon and two parts oxygen. Although natural CO2 emissions are necessary to sustain a temperature suitable for life on Earth, an excess of man-made emissions can be harmful to the environment and contribute to global warming. Since the Industrial Revolution, CO2 has been rising steadily to the point where levels have reached those of the period that triggered the last ice age.
Government Carbon Capture Programs
Many countries are implementing carbon capture programs to combat climate change through the sequestration of carbon and other pollutants from the atmosphere.
In the United States, the Department of Energy (DOE) has created a step-change program to encourage fossil fuel companies to mitigate carbon emissions to lower both cost and potential energy penalties. The Carbon Capture Program targets two specific areas of the carbon emission sector: Pre-Combustion Capture and Post Combustion Capture.
Pre-Combustion Carbon Capture
Pre-combustion carbon capture is a process that captures carbon dioxide (CO2) from fossil fuels before they are burned. This is done by using a gasification process to convert the fossil fuel into a mixture of hydrogen gas and carbon dioxide. The hydrogen gas is then used as fuel, and the carbon dioxide is captured and separated for storage or use in other processes.
The pre-combustion carbon capture process typically involves three main steps:
- Gasification: The fossil fuel, typically coal or natural gas, is reacted with steam and oxygen to produce a mixture of hydrogen gas and carbon dioxide.
- Gas cleanup: The mixture of hydrogen gas and carbon dioxide is then cleaned to remove impurities such as sulfur, mercury, and other pollutants.
- Carbon capture: The carbon dioxide is separated from the hydrogen gas using a chemical process and then compressed and transported for storage or use in other processes.
Pre-combustion carbon capture is a promising technology for reducing greenhouse gas emissions from power plants and other industrial processes that use fossil fuels. However, it is still an expensive and energy-intensive process, and more research is needed to make it more efficient and cost-effective. Additionally, there are concerns about the safety and long-term viability of storing large amounts of carbon dioxide underground. Therefore, pre-combustion carbon capture must be used in conjunction with other sustainable energy solutions to reduce greenhouse gas emissions and mitigate climate change.
Post Carbon Sequestration
Post-combustion carbon capture is a process that captures carbon dioxide (CO2) from flue gas emissions after fossil fuels are burned. This process can be retrofitted onto existing power plants and industrial facilities, making it a potentially useful technology for reducing greenhouse gas emissions.
Post-combustion carbon capture typically involves the following steps:
- Flue gas scrubbing: The flue gas emissions are passed through a scrubbing system, which uses a solvent to absorb the carbon dioxide. The solvent is typically an amine solution that chemically binds with the CO2.
- CO2 separation: The CO2 is separated from the solvent using a distillation or other separation process, creating a high-purity stream of carbon dioxide.
- Compression and transport: The high-purity CO2 stream is compressed and transported for storage or use in other processes.
Post-combustion carbon capture is a promising technology for reducing greenhouse gas emissions from power plants and other industrial processes that use fossil fuels. However, it is still an expensive and energy-intensive process, and more research is needed to make it more efficient and cost-effective. Additionally, the captured carbon dioxide must be safely stored or utilized to prevent it from entering the atmosphere and contributing to climate change. Therefore, post-combustion carbon capture must be used in conjunction with other sustainable energy solutions to reduce greenhouse gas emissions and mitigate climate change.
Biological And Non-Biological Carbon Sequestration
Biological carbon sequestration, also known as biosequestration, is the process of capturing and storing carbon dioxide (CO2) in living organisms and ecosystems. This process occurs naturally in plants and animals through photosynthesis and respiration, and it can also be enhanced through land management practices that promote carbon storage in soils, vegetation, and forests.
Biological carbon sequestration has several forms, including:
- Afforestation: Afforestation and reforestation are both terms that refer to the process of planting trees in areas where forests did not previously exist or where forests have been depleted or destroyed. Afforestation is the establishment of a forest, or stand of trees, in an area where there was no forest before. This can be done for a variety of reasons, such as creating new habitats for wildlife, restoring degraded lands, or mitigating climate change by capturing carbon dioxide from the atmosphere.
- Reforestation: Reforestation, on the other hand, refers to the process of replanting trees in areas where forests have been cleared or degraded. Reforestation can help restore forest ecosystems and provide important benefits such as carbon sequestration, soil conservation, and protection against erosion.
- Soil carbon sequestration: Certain agricultural practices, such as reducing tillage, adding organic matter to soil, and using cover crops, can increase the amount of carbon stored in the soil. This can help improve soil health and increase the productivity of crops.
- Wetland restoration: Wetlands are natural carbon sinks that can capture and store large amounts of carbon. Restoring and protecting wetlands can help prevent the release of carbon dioxide from wetland degradation and help sequester additional carbon in the soil.
- Bioenergy with Carbon Capture and Storage (BECCS): BECCS is a technology that involves capturing carbon dioxide from bioenergy production and storing it in underground reservoirs, effectively removing carbon dioxide from the atmosphere.
Biological carbon sequestration is an important strategy for reducing greenhouse gas emissions and mitigating climate change. However, it is not a silver bullet and must be used in conjunction with other strategies to reduce greenhouse gas emissions, such as transitioning to renewable energy sources and increasing energy efficiency.
Artificial Carbon Sequestration
Several companies have sprung up with artificial tree technology to capture carbon from the air and sequester it in the ground. Nice idea but an artificial tree is nowhere as effective as a real tree for the price. For example, a million-dollar artificial tree removes on average 100 tons of carbon from the atmosphere; an acre of real trees does the same thing for $10,000. Despite the cost disadvantage of artificial tree technology, it has some advantages; carbon capture begins immediately after installation, while trees must grow and mature to be most effective. An artificial tree can be installed at the pollution source, where real trees may not grow in a highly toxic environment. Artificial trees require electrical power and maintenance; real trees do not and as such represent the most cost effective and sustainable means for carbon capture.
