Testimony To EPA on Carbon Rule for New Coal and Gas Power Plants, 

Feb. 6, 2014 

Richard H. Ball, 

Retired Energy Policy and Technology Analyst 

SUMMARY OF FINDINGS AND RECOMMENDATIONS 

I support the proposed NSPS rule as a very important step forward in reducing 

U.S. carbon emissions and a signal to the rest of the World about our 

seriousness in mitigating global warming and ocean acidification. However, I 

believe the proposed regulations are quite conservative and it would be 

possible and desirable to strengthen and improve upon this rule in several 

key respects, as follows: 

• The rule for natural gas plants could be made more stringent to better 

reflect the best available technologies for generating electricity from 

natural gas. For example, many new CCGT plants in service achieve 

carbon emissions of less than 8001b/MWhgro..l.z Natural gas effectively 

is getting a free ride on CO2 control. 

• The proposed coal plant standard, while a huge step forward, still 

appears weaker than it should be since it is based on only a 40% 

crapture rate by CCS equipment. Several coal plants under construction 

and desfgns exist for all types of new coal plants with CCS that 

incorporate capture rates of up t 90%. Such plants with 90% capture 

translate to COz emission rates ess uc than 300 lb/MWhgoss.i It 

probably would be economical y inefficient to build a coal plant with a 

more modest rate of capture and then have to require a later major 

retrofit to a higher level when it becomes necessary to reduce carbon 

emissions even further in the future. 

• Greenhouse gases (GHG) other than COz should be taken into account, 

especially methane (which is the major component of natural gas) and 

considerable leakage occurs in the natural gas production and use cycle. 

• If CCS is applicable to coal-fired power plants, in theory it should be 

even more applicable to natural gas-fired CCGT plants because it is 

technically easier and more cost-effective to apply carbon capture to 

more thermally efficient plants (although none appear to have actually 

been demonstrated). Designs for NGCC with 90% capture indicate COz 

emission rates of less than 1001b/MWh (net or gross). 1 

• From a systems perspective, several other attributes of power plants 

than just lb of COz per kWh at the stack affect the overall contribution to 

the electric grid. These attributes potentially could be evaluated and 

possibly included in an integrated rule, at least in a future iteration of 

the NSPS. They include: 

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o Ability of the plant to ramp power output up and down rapidly to 

respond to grid needs, which can greatly affect the ability to 

integrate intermittent renewables into the grid and the need to 

operate higher emitting sources such as peaking turbines or old 

coal and gas plants (thereby further reducing greenhouse gas 

emissions beyond those of the unit in question). 

o Consideration of fuel cycle emissions of GHGs from production of 

natural gas and other fuels used in power plants. That might 

place natural gas plants on a more level playing field with other 

fuels and thus be viewed as more fair. (However, in accounting 

for methane emissions in general, EPA should use a more 

realistic formula for its impact than the simple GWP 100-year 

estimate of 21, which is now out of date and does not reflect the 

latest atmospheric chemistry nor its short-term impact, which 

can lead to effective GWP values greater than 100.) 

• However, since some of those improvements might complicate the 

regulatory process and since basing the coal standard on partial 

implementation of CCS arguably will have little or no practical effect in 

the next few years, I would urge EPA to move forward with the rule as 

proposed in preference to delaying the process, but preferably with 

tighter numerical limits. More far-reaching improvements should be 

considered for implementation in the next few years. 

• EPA and other agencies of the Federal Government should be moving 

forward to analyze the overall longer-term impacts of all fossil plants 

that may be constructed in the near future and considering whether 

effort should be put into encouraging demonstration of CCS technology 

applied to natural gas plants. 

DISCUSSION 

Natural Gas Standard. 

In the case of carbon emissions from natural gas plants, it is clear that, short of CCS, 

the technology for reducing emissions cannot be separated from the overall 

generation technology: there does not seem to be a separate control technology as 

such. Hence it is appropriate for EPA to identify a level of BSER in terms of an 

emission stiindard that is specific to the best performing generation technology. 

The natural gas power plant NSPS rule does not appear to me fully to reflect the best 

performing CCGT natural gas plants currently available on the market. Annual 

average data from several new power plants indicate they achieve gross rates of 

about 780 lb/MWhg,oss, well below the proposed NSPS rule. z Hence, basing the rule 

on the best units should permit a standard much lower than 10001b/MWh. 

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Peaking turbine units, not included in the rule, are less efficient and thus achieve 

poorer emission rates. However, some new CCGT units (e.g., GE's F1exEfficiency 

units) have much better ramp-up and down performance and thus could also serve 

some of the load following functions for which peaking turbines are now applied, 

thus reducing the need for stand-alone peaking turbines. They also have greater 

potential to perform load following and thus assist integration of intermittent 

renewables such as wind and solar power into the grid. Perhaps credit for such 

technology could be incorporated into the formula for an overall carbon standard. 

(While it is not clear how to do that in the context of a pure NSPS standard, it might 

be factored into the future rule for reducing overall carbon emissions from 

electricity production from new and old units within some utility system or state, 

depending how that rule is formulated.) 

EPA argues that a CCS-based standard for natural gas plants cannot be justified at 

this time because the technology has not been tested. That is unfortunate from a 

CO2-mitigaton strategy perspective because many new CCGT gas plants currently 

are being built and they may continue to operate for decades into the future when 

accelerated reductions in GHG emissions will become necessary. In addition, the 

amount of upstream emissions of inethane from natural gas production activities 

currently is controversial, potentially greatly increasing the total GHG footprint of 

these plants. If implemented as proposed, it will be important to revisit this 

standard ASAP and for the Federal Government to implement policies to 

demonstrate CCS on such plants so that future regulation is possible. A neglected 

issue in decision-making on new plant installations is whether they should be 

designed and sited so that future retrofit with CCS is feasible, which does not appear 

to be the case for plants that have recently been built or proposed in my state of 

Virginia. 

Coal Standard. 

Carbon ernissions will depend on the degree of COz capture, which in turn will affect 

costs and net energy output Capture rates in plant engineering designs assume 

that up to 90% removal is feasible from different coal technologies, ranging from 

IGCC to conventional PC subcritical combustion. For all the five coal technologies 

studied by DOE/NETL, CO2 emissions varied from well under to just slightly over 

2001b/MWh (about one fifth of the 11001b proposed standard). For purposes of a 

longer-term carbon mitigation strategy it makes sense to me to set a higher 

standard so that no coal plants are built that are economically suboptimal due to the 

need to later retrofit them or else suffer the climate impact consequences of 

continued operation at much higher emissions than necessary. However, EPA 

makes the case that partial CCS implementation at much less than 90% capture 

might not pass all the BSER criteria of adequate demonstration and cost Setting a 

higher removal/lower emission standard might jeopardize the standard. Given the 

need for prompt action to curb CO2 emissions, it arguably makes sense to proceed 

with the proposed standard. Again, I believe this standard should be re-visfted 

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ASAP and revised to be more stringent as soon as more data on demonstrated CCS 

systems is available to justify it. 

Conclusions 

It appears that natural gas CCGT plants are getting a free pass on CO2 controls. 

Justification for a standard of 10001b/MWh appears inadequate in view of current 

CCGT technology already in widespread operation. This is not a technology forcing 

standard. 

Since CCS is not required for natural gas, the proposed standards effectively favor 

natural gas over solid fossil fuels and thus exacerbate the current competitive 

advantage of natural gas over coal and continue its advantage over carbon-free 

renewable sources. While EPA justifies the proposed standards by the current 

technological situation, strategically this will lead to over-dependence on natural 

gas investments that will persist in time and make carbon mitigation policy more 

difficult in the future at a time when U.S. and global GHG emissions. In addition, 

unless much more stringent regulations and greatly improved industry best 

practices can reduce fugitive emissions of inethane in the natural gas fuel cycle, 

especially gas production and processing, purported advantages of natural for 

electricity production are likely to be an illusion. EPA Carbon rules for both existing 

and new plants, augmented by other government policies, will be required to 

achieve a satisfactory degree of GHG mitigation or the stock of power plants, 

including natural gas plants built in the near future, will seriously undermine 

mitigation efforts. 

1

"Cost and Performance Baseline for Fossil Energy Plants Volume 1: Bituminous Coal and 

Naturral Gas to Electricity°, Revision 2a, September 2013, DOE/NETL-2010/1397 

2 "How Stringent is the EPA's Proposed Carbon Pollution Standard for New Power Plants?" By 

Matthew J. Kotchen* and Erin T. Mansurt, NBER, August 3, 2012. 

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