Direct utilization of geothermal energy from low-enthalpy areas, such as room
and water heating in various ways, often offers mitigation advantages and the same
relates to heat pumps. Direct-use emissions are low, as they do not surpass standard
natural background emissions on average. For instance, the Reykjavík district
heating facility emits about 0.5 mg CO 2 kWh
À1 Fridleifsson et al. (2008), so the
mitigation effects can be substantial. Fridleifsson et al. (2008) measured the mitigation capacity of heat pumps to surpass 200 million tons of CO 2 /year, as the heat
pumps substitute for older fossil-fueled systems. Other direct application potential
reductions amounted to more than 90 million tons of CO 2 /year.
In addition to mitigation potential from indirect utilization of power generation
and heat pumps, the total sustainability potential refers to approximately 12% of total
GHG emissions by 2050, if compared with the IEA 2015 reference scenario, without
carbon capture and storage.
CCS and CCU
Carbon capture and storage (CCS) is the method of trapping, transferring, and
depositing CO 2 from relevant point sources such as power stations to a storage
location, usually in an underground landform such as deep aquifers. The objective is
to not bring CO 2 into the atmosphere. CCS has been active throughout the growth of
the geothermal sector. A new approach called Carbfix has lately been scientifically
proven to work by researchers at the University of Iceland, Columbia University,
and Reykjavik Energy. The Carbfix program “fixes” carbon by breaking down CO 2
into water and reinjecting it deep into the subsurface into basaltic volcanic rocks. As
this happens, the CO 2 becomes a solid mineral (calcite) and thus can be retained for a
long time. Recent findings indicate that this approach is successful because 95% of
the injected carbon is calcified within 2 years (Matter et al. 2016).
However, the process has its drawbacks because the process requires vast quantities of water and is region specific because it uses basaltic rock. However, it
complements other CCS approaches mainly depending on reinjection into
sedimentary rock.
Carbon capture and use (CCU) is a method of extracting CO 2 from plants, but
instead of retaining it deep underground, the carbon is used in industrial and
horticultural applications (Ogola et al. 2012a). Applications for horticulture include
use in greenhouses and industrial uses include the transformation of CO 2 using
chemical reactions into methanol, which can be used for transportation (Ogola et al.
2012a, b).
11 Geothermal Energy and Climate Change Mitigation
261
and water heating in various ways, often offers mitigation advantages and the same
relates to heat pumps. Direct-use emissions are low, as they do not surpass standard
natural background emissions on average. For instance, the Reykjavík district
heating facility emits about 0.5 mg CO 2 kWh
À1 Fridleifsson et al. (2008), so the
mitigation effects can be substantial. Fridleifsson et al. (2008) measured the mitigation capacity of heat pumps to surpass 200 million tons of CO 2 /year, as the heat
pumps substitute for older fossil-fueled systems. Other direct application potential
reductions amounted to more than 90 million tons of CO 2 /year.
In addition to mitigation potential from indirect utilization of power generation
and heat pumps, the total sustainability potential refers to approximately 12% of total
GHG emissions by 2050, if compared with the IEA 2015 reference scenario, without
carbon capture and storage.
CCS and CCU
Carbon capture and storage (CCS) is the method of trapping, transferring, and
depositing CO 2 from relevant point sources such as power stations to a storage
location, usually in an underground landform such as deep aquifers. The objective is
to not bring CO 2 into the atmosphere. CCS has been active throughout the growth of
the geothermal sector. A new approach called Carbfix has lately been scientifically
proven to work by researchers at the University of Iceland, Columbia University,
and Reykjavik Energy. The Carbfix program “fixes” carbon by breaking down CO 2
into water and reinjecting it deep into the subsurface into basaltic volcanic rocks. As
this happens, the CO 2 becomes a solid mineral (calcite) and thus can be retained for a
long time. Recent findings indicate that this approach is successful because 95% of
the injected carbon is calcified within 2 years (Matter et al. 2016).
However, the process has its drawbacks because the process requires vast quantities of water and is region specific because it uses basaltic rock. However, it
complements other CCS approaches mainly depending on reinjection into
sedimentary rock.
Carbon capture and use (CCU) is a method of extracting CO 2 from plants, but
instead of retaining it deep underground, the carbon is used in industrial and
horticultural applications (Ogola et al. 2012a). Applications for horticulture include
use in greenhouses and industrial uses include the transformation of CO 2 using
chemical reactions into methanol, which can be used for transportation (Ogola et al.
2012a, b).
11 Geothermal Energy and Climate Change Mitigation
261