INGENIEUR
these benefits, the construction of new CFPPs
must evolve from subcritical to supercritical, USC
and A-USC. A less capital-intensive alternative
to the construction of new HELE CFPPs includes
the retooling of aging CFPPs to produce electricity
more efficiently. By upgrading plant machinery
including boilers and turbines, as well as improving
operational practices, including preventative O&M
to increase plant reliability, efficiency gains can be
had without the high upfront capital requirements
associated with the construction of a new CFPP. As
CFPPs age, their efficiency can become degraded;
however, with O&M investment and retooling,
these effects can be mitigated. In addition to
increasing CFPP efficiency, flexibility must also
be addressed by improving the ability of CFPPs to
quickly adjust power generation levels in order to
balance the increasing integration of intermittent
generation sources such as VRE. Dispatchable
coal-fired generation from flexible HELE CFPPs
will form an essential part of a stable and flexible
electricity grid alongside flexible generation
including hydropower and natural gas.
Externalities in Coal for Power
Generation
In general, HELE produces 10% less air pollution,
including NOx, SOx and mercury, than traditional
generation (per kWh) due to its more efficient
combustion, requiring fewer fuel inputs (coal) in
order to generate the same amount of electricity.
However, these externalities can be difficult
to quantify, and various factors need to be
considered when determining the most efficient
generation technology based on (long-term) cost.
In general, externalities such as adverse impacts
on health and local environment are not included
when calculating generation costs, including
LCOE. When these external costs are included,
the case for more efficient electricity generation
technologies becomes clearer.
Given the intensity of GHG emissions from
coal combustion, end-of-pipe solutions including
carbon capture and storage (CCS) are critical to
making coal-fired power generation sustainable
by reducing up to 99% of CO2 emissions. This
would make coal combustion emit less than
100g per kilowatt-hour, which is still double the
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Coal remains a major energy source
emissions of PV technology but one-tenth of
current lifecycle emissions.
Operating CFPPs also consume vast quantities
of water, a cause of major concern in arid regions
and regions where water resource issues are
gaining prominence. Non-GHG pollutants, such as
NOx, SOx and mercury, can cause severe health
issues and often harm local infrastructure and,
consequently, the