My comment follows below the break (warning: words ahoy).
Dear Administrator
McCarthy,
As an assistant
professor of nuclear engineering at the University of Tennessee and a member of
the American Nuclear Society, I appreciate this opportunity to provide feedback
on the EPA’s rulemaking process. As a nuclear engineering professional, I
sincerely believe that nuclear energy can and must play a role helping to
produce a sustainable, economical, and reliable domestic energy supply while
balancing environmental considerations.
While I believe that
the risks of climate change warrant federal action to limit carbon dioxide
releases and that the electric power sector is one of the most efficient places
to enact such regulations, I am concerned that several facets of the EPA’s
proposed rulemaking, while well-intentioned, may be counterproductive toward
the ultimate goals of carbon dioxide emission abatement.
My chief concerns fall
into the following categories regarding nuclear energy in the proposed Baseline
System of Emissions Reductions (BSER) formula:
- The EPA’s discounting of existing nuclear generating capacity is both inappropriate and limits incentives to preserve and extend the life of existing low-carbon baseload electricity production
- The EPA’s inclusion of five proposed, under-construction nuclear units in the state-level emissions fails to credit states and electric utilities for forward-looking actions in anticipation of carbon regulation, in effect acting as a penalty for early action
- The EPA needs to produce clear rules covering nuclear generating unit capacity up-rates for the BSER state-level formulas
- The EPA BSER formula for state nuclear capacity should reflect a more current baseline to reflect the recent closure and announced closures of several nuclear generating units
Issue 1: Inclusion of only 5.8% of state-level nuclear generating capacity is inappropriate
Proposed remedy: The EPA should consider 100% of state nuclear generating capacity in
calculating state-level BSER goals
Explanation:
In the basis for the proposed rulemaking (“Carbon Pollution Emission Guidelines for Existing
Stationary Sources: Electric Utility Generating Units” – hereafter referred to
the Guidelines), the EPA indicates, “Another way to increase the amount of
available nuclear capacity is to preserve existing nuclear EGUs that might
otherwise be retired.”
In this same section, the EPA notes that an Energy Information Agency (EIA)
report indicating 5.7 GW of domestic nuclear generating capacity being,
“at-risk.” As this capacity is approximately 5.8% of the U.S. nuclear fleet
capacity, the EPA assigns a credit of 5.8% of existing nuclear generating
capacity to meeting state-level BSER goals, under the logic that this credit
would encourage the preservation of these units (and therefore defer their
replacement with more carbon-intensive sources).
However, there are
several flaws with this line of reasoning. Given that the retirement of nuclear
units is both a discrete event (occurring within a single state’s borders and
thus counting only toward that state’s carbon dioxide abatement goal) and given
that nuclear units tend to be of relatively large capacities (i.e., generally
from 600-1100 MWe in scale), the loss of even one nuclear generating unit
constitutes a significant handicap towards carbon abatement, given that the
replacement power has almost entirely been made up from natural gas-fired
turbines, which emit non-trivial amounts of CO2 in their operations.
Yet the current rule as proposed accounts for neither of these factors.
Distributing the
risk of 5.7 GWe of “at-risk” nuclear capacity across 30 states makes little
sense, given that at-risk capacity is concentrated within a few states. Rather,
the formula should explicitly account for losses of nuclear generating capacity
due to both planned and unplanned retirements (i.e., premature closures due to
economic and other forces). For the rule to be effective, states that allow (or
even encourage) the closure of nuclear units should be compelled to provide for
an equivalent zero-carbon electric capacity or subsequent offsets
through other reductions in the BSER formula (e.g., demand-side reductions,
etc.)
As currently
proposed however, states that retire nuclear units only need to make up 5.8% of
the lost capacity, a facet that introduces unanticipated, perverse consequences
under the proposed BSER formula. An example of such perverse effects was
uncovered by my graduate students, Remy Devoe and Justin Knowles, who undertook a comprehensive evaluation of the effect of premature nuclear plants closures
under the Clean Power Plan as-proposed. Their findings – which are based on the
provided EPA BSER spreadsheets – indicated that for 15 states, the closure of
all nuclear generating units and the subsequent replacement with an equivalent
capacity of natural gas-fired units (again, the most likely alternative) would
result in a net decrease in calculated emissions under the EPA BSER
formula, despite the clear fact that physical CO2 emissions
precipitously increase.
Similarly, parallel examinations by others have come to the same conclusion.
It is almost certain
that the EPA does not intend to reward states for increasing CO2
emissions from the electric power sector; therefore an incentive structure
which facilitates just that violates the stated goals of the plan.
The simplest and
most appropriate means of remedying the proposed rule would be for the EPA to
consider all electricity generation sources in the BSER formula
denominator – i.e., fossil, nuclear, hydro, and renewables. In this sense then,
the BSER formula would then roughly correspond to physical carbon intensity
from electricity generation. In this sense then the emissions formula in fact
becomes far more straightforward; states simply need to tally carbon emissions
(i.e., taking a standard CO2 per MWh for fossil sources, multiplied
by the MWh produced) in the numerator and then the total state electricity
generation in the denominator. Offsets for demand-side reduction can then
similarly be taken at the fleet-average carbon intensity; i.e., such reductions
should be credited on a per-MWh basis weighted by the average CO2/MWh
intensity of the entire electric generating fleet within a state.
The proposed remedy
thus encourages states to maintain nuclear generating units as well as other
low-carbon electricity sources while also being far simpler and avoiding
potentially perverse outcomes. Further, this remedy incentivizes states to consider
future, planned retirements of nuclear units as they reach the end of their
current round of license extensions to 60 years (beginning around 2020),
wherein it is anticipated only a fraction of the current nuclear generating
fleet will be awarded additional license extensions to operate for 80 years.
Given that these retirements are an entirely foreseeable event, it is entirely
prudent that EPA rulemaking also consider these effects within their
rulemaking. A rule which considers CO2 abatement on a strictly
physical basis (i.e., looking solely at CO2 emissions from the
electric power sector over total electric power generation) would easily
accommodate this.
Certain stakeholders
may object to the rather severe penalty raised by fully crediting the loss of
nuclear units against a state’s carbon abatement goals (unless replaced
or otherwise offset by zero-carbon sources and other BSER build blocks, like
efficiency improvements and demand-side reductions). However, again – the basis
of rulemaking should be on the physical abatement of CO2
emissions from the electric power sector, not an “accounting” abatement. The
Clean Power Plan should therefore hold states and utilities accountable to
maintaining gains in CO2 abatement and avoid “loopholes” that emerge
by discounting nuclear power generation and other zero-carbon sources (such as
hydropower).
Finally, in public
comments on the rule as proposed, certain stakeholders have expressed
opposition to the inclusion of nuclear at all within the EPA BSER formula, giving
varied (and dubious) objections to the use of nuclear energy writ large.
However, I would argue here that such objections to nuclear energy are well
beyond the scope of this issue, which is focused on carbon dioxide emissions
abatement. As nuclear energy constitutes a majority of the zero-carbon electric
capacity in the United States, the logic for its inclusion in the BSER formula
should be obvious: any rule concerning carbon dioxide intensity regulations
must appropriately and fully credit the contributions of nuclear electricity
generation to this goal.
However, going one
step further, given that the ultimate goal of the EPA Clean Power Plan is in
the reduction of carbon dioxide emissions, the plan should in principle remain
neutral to the technological means used to achieve this end, giving states and
stakeholders the flexibility to achieve emissions reductions in the manner that
best suits their unique interests. To emphasize; the objective of the proposed
rule should be in the reduction of carbon dioxide pollution from the electric
power sector and not in setting a de facto national energy policy. In this
sense, the appropriate role of the EPA is to set clear, measurable standards –
such as carbon intensity targets for the electric power sector – and then
measure compliance solely on the basis of performance to this target, rather
than attempting to dictate specific emissions reductions strategies through
selective application of weighting to particular energy sources.
Issue 2: Inclusion
of the five proposed, under-construction nuclear units in setting state-level
BSER goals undermines early action on CO2 abatement goals
Proposed remedy: The EPA should only include new nuclear generating capacity in
state-level calculations on a “first electrons to the grid” basis
Explanation:
In the Clean Power Plan rule Guidelines, the EPA indicates the following logic behind including these units under construction as counting
toward the computation of the state goals as follows:
The EPA believes that since the decisions to construct these units were made prior to this proposal, it is reasonable to view the incremental cost associated with the CO2 emission reductions available from completion of these units as zero for purposes of setting states' CO2 reduction goals (although the EPA acknowledges that the planning for those units likely included consideration of the possibility of future regulation of CO2 emissions from EGUs). Completion of these units therefore represents an opportunity to reduce CO2 emissions from affected fossil fuel-fired EGUs at a very reasonable cost. For this reason, we are proposing that the emission reductions achievable at affected sources based on the generation provided at the identified nuclear units currently under construction should be factored into the state goals for the respective states where these new units are located.
However, the reasoning of this is precisely backwards. Such states have made a choice to build nuclear generating units (in contrast to other available alternatives, most especially natural gas combustion turbines) explicitly upon the anticipation of future carbon dioxide regulations. The rule in effect penalizes these states for taking early action to mitigate carbon dioxide emissions from their respective electricity sectors.
Further, the basis for the decision that the marginal cost is in effect zero and therefore that these should be counted directly toward computation of state-level goals is similarly baffling. It is indeed true that the marginal cost of completing the units, after making the decision to build and raising the appropriate capital, is indeed small – and thus the completion of these units as a carbon abatement strategy makes economic sense. However, it does not follow at all that
these states should be given no credit for these units toward meeting their
carbon dioxide abatement goals.
For one, any examination of the marginal costs of carbon
abatement strategies should be applied solely to whether the rule represents a
reasonable burden upon states and utilities; in this case, because the marginal
cost is low, the rule indeed can be met with minimal additional economic
consequences. However, no electricity has been produced from these plants, and
it is further reasonable to assume that the construction of these plants has
offset construction of more carbon-intensity generation alternatives (e.g.,
coal and natural gas).
Second, the decision to include these plants within
state-level goal calculations effectively penalizes these states as being
“early movers” and sets a negative precedent for future, forward-thinking
action by states and utilities to voluntarily move forward with large,
carbon-free electric projects. Numerous interviews with Southern Company
executives for example have indicated that the Vogtle units have been partially
motivated as a hedge against future carbon dioxide emissions constraints; this
kind of forward thinking should be rewarded. Instead, the current rule takes
these plants as a given and assigns them no contributions to future carbon
abatements under the rule. If the rule stands as-written, it is likely future
utilities will defer similar projects not explicitly compelled by regulatory
compliance such that their construction is appropriately credited to compliance
goals.
Finally, contrary to the assumptions of the EPA rule-making,
the completion of these units is not a given; one need look no further than
Watts Bar Unit 2, currently being finished by TVA. Construction on Watts Bar
Unit 2 was suspended in 1988 due to declines in electricity demand and did not
resume until 2007, with an expected completion in 2015. The EPA should not
penalize states and utilities that have expressed future ambitions on carbon
reduction strategies through nuclear deployments; rather, given the extended
timelines for nuclear unit construction, these units should instead be counted
toward meeting state-level goals, rather than in computing more stringent goals
by assuming their completion.
A fair, appropriate standard that would be simple to
implement would be one based on a “first-electrons-to-the-grid” standard, which
can be applied to all electric generation units. Per this standard, a unit
would not be counted toward state-level compliance until commercial electricity
production begins, being credited on a pro-rated basis; for example, a unit
which begins operations starting July 1 and continuously supplying power would
be credited at half the rated capacity (i.e., assuming it supplies at full
rated capacity continuously from July 1-Dec 31). This standard would
appropriately incentivize the development of new low-carbon sources while being
broadly applicable across a number of generating sources. (A similar rule could
likewise be applied to decommissioning of units, such as from the retirement of
coal-fired units.)
Critics of this proposal would contend that this allows
states to satisfy their mandated carbon abatement goals “too easily” – in
effect doing so through the construction of a single nuclear project. However,
this should be considered a feature, not a bug; in other words, if the EPA goal
is to encourage carbon abatement as early as possible with a minimum of
disruptive economic impact, then new nuclear units should be considered a
perfectly appropriate way of meeting this goal and regulate accordingly.
Further, again; the goal of a properly-structured carbon dioxide emissions
constraint should be to set a clear, measurable standard and then allow states
and utilities the maximum degree of freedom possible in meeting this target.
Thus, whether or not a state meets this goal though planned nuclear
construction is entirely irrelevant; the goal should be for the state to meet the
abatement standard, not in satisfying a particular vision of energy policy
embraced by particular stakeholders or the EPA.
Issue 3: The
EPA needs to produce clear rules on nuclear generating unit capacity up-rates
Proposed remedy: The EPA should clearly indicate that nuclear generating unit capacity
up-rates will be credited toward building block 3 in the BSER state goals.
Explanation:
Nuclear generating
unit capacity up-rates (i.e., increases in operating power from the original
licensed operating power) have cumulatively accounted for over 7,000 MW of new electric generating capacity since 1977, the equivalent of building seven new
nuclear generating units. Given
the substantial electric generating capacity provided by power uprates at
existing nuclear plants, it is logical to expect that these capacity uprates
will continue for newer plants with the continued development of more
sophisticated core designs that allow for less design conservatism. These types
of power uprates represent “low-hanging fruit” to states and utilities, as they
are typically far more cost-effective to implement than building new plants,
especially as nuclear generation has one of the lowest marginal costs of
electricity production among all sources.
Given the historic
trend, under a carbon dioxide emissions regime it is likely that continued
power uprates will be considered as a means of meeting state-level CO2
abatement goals. The EPA should therefore move to specifically clarify the role
of nuclear capacity uprates within the rule, crediting these at 100% of the
rated electrical capacity (equivalent to new unit construction) within Block 3
of the BSER.
Issue 4: The
EPA BSER formula should reflect a more recent baseline for state nuclear
generating capacity
Proposed remedy: The EPA state-level goals should reflect recent closures in nuclear
generating capacity through a more recent baseline (such as 2014 or 2015)
Explanation:
Several recent
nuclear plant closures (and one announced closure) warrant an updated baseline
for EPA evaluations, especially given the relative size of nuclear generating
units. These closures include:
Name
|
State
|
Closure date
|
Capacity (MWe)
|
Crystal River 3 Nuclear Power
Plant
|
FL
|
2/2013
|
860
|
Kewaunee Power Station
|
WI
|
5/7/2013
|
556
|
San Onofre Nuclear Generating
Station (SONGS), Units 2 & 3
|
CA
|
6/2/2013
|
2 x 1127
|
Vermont Yankee Nuclear Power
Plant
|
VY
|
12/2014
|
620
|
Cumulatively, the
closure of these units reflect a loss of 4,290 MWe of nuclear generating capacity
which will almost certainly be made up through the construction of natural
gas-fired capacity, resulting in a net increase in CO2. For some
states (such as Vermont, which is exempted from state-level goal calculations
as it had no carbon dioxide-emitting plants as of the proposed baseline year),
these closures will represent a fundamental shift in the state electricity
portfolios and therefore should be reflected in future estimates, especially if
additional nuclear units are closed and replaced with carbon-emitting sources
such as natural gas turbines.
Conclusion
While I believe that
regulatory strategies to mandate carbon dioxide emissions are both justified
and necessary by the potential risks of climate change, the EPA Clean Power
Plan rule as-proposed contains several flaws in its treatment of nuclear power
which arguably work to undermine its goals. A consistent, technology-neutral
approach to carbon dioxide emission regulations – such as a mass-based formula
for CO2 emissions intensity (i.e., calculating total mass of
CO2 emitted by the electric power sector in each state over the
total electric power produced from all sources) would eliminate much of the
perverse incentives currently present and produce a fairer, more workable rule.
Thank you for your consideration of my comments.
Sincerely,
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