There is a basic economic problem with coal/carbon capture that gets far too little attention. Namely, it is the only low/zero carbon generation technology that requires an increase in fuel combustion. As a practical matter, this means that carbon capture will never be economic in any world that provides an incentive for low-carbon generation to come forward -- so long as one assumes that carbon will ultimately be priced in some sort of a market, bid up to the marginal cost of supply. Nuclear, renewables and energy efficiency all have their own economic strengths and weaknesses, but all have innately lower operating costs than a coal plant with CCS, and once built will necessarily cause the price of CO2 reduction to clear below the level required to justify the operation of a CCS facility. One doesn't need to be quantitative to prove this point -- it is sufficient to note merely that the parasitic loads required to operate a CCS plant will increase fuel use, and no one is giving away fuel for free.

For CCS to play a role in CO2 reduction therefore requires that two things will happen: (1) technology development will eventually bring capital costs down to a level necessary to sustain investment and (2) every other CO2 reduction strategy we deploy will be insufficient to meet our CO2 goals and we will have to also run CCS. (And that we will run CCS facilities sufficiently hard to generate revenues necessary to recoup the original investment.) The first might be possible, but is by no means guaranteed. But the second virtually guarantees that the first will never happen. Why would any investor commit to investing in a technology that loses money on the margin? Absent such investor belief, how will we gain sufficient experience to drive capital expenditure down?

By all means, let's get CO2 emissions down. And by all means, let's chase fuel efficiency (including efficient use of coal) as a part of that strategy. But let's be much more skeptical of claims that reducing the efficiency of coal-fired power is the key to an economically-sustainable, carbon-constrained future.

Sean Casten
President & CEO
Recycled Energy Development, LLC

Your article is right on the money; increasing power generation efficiency is, in my opinion, a viable option for reducing GHGs, as suggested in the GAO report. You then go on to list mitigating actions that might bring us closer to this goal, but these all seem to be out there in the future somewhere. My concern is, what do we do in the meantime? You mention plant efficiencies starting at 35 percent "of the energy input converted to electricity". Whatever happened to the remaining 65 percent of this energy? I would like to set the record straight on this issue.

Without going into the intricacies of plant heat balance, it is generally accepted by the engineering community at large that almost 62 percent of this unused energy, or 40 percent of the total energy input, is lost via the steam condenser cooling system. This is more than the plant's output; what a bonus it would be if we could turn at least a portion of this energy into additional electricity. And it would be non-disruptive, meaning that some of the other proposed technologies could still be added at a later date, thus increasing plant efficiency even further.

Well, there are some farsighted companies tackling this very issue. We have Recycled Energy Development and Ormat Technologies, active in waste heat recovery in some other fields. And there are indications that the list might be growing; I sincerely hope so.

In closing, I urge everyone not to overlook the potential of waste heat recovery as a sort-term means for reducing GHGs or, for plant owners and operators, just a common sense approach to increase revenues.

Alan E. Belcher

Interesting article. However, let's not forget that gas plants emit CO2 also, albeit about half the amount per MW as coal. So, gas plants are CO2 polluters too. Something needs to be done with CO2 from gas plants as well! Gas plants are not so CO2 "innocent".

Charles Diestel

You use the term "harmful emissions" in your article. I'm still puzzled by the placement of CO2 in that category. I recently read a CO2-oriented question to the effect of "What environmental benefit may be achieved by mandating permits to limit a uniformly distributed, constituent of clean air, vital to all life, that is emitted by all productive activities on Earth?" If alarmists were to turn the global warming hysteria in the direction of the most abundant greenhouse gas, we'll soon be banning water vapor. I should apologize for mentioning this because it may well plant a seed with the current Administration and especially the EPA, which seem to do a great job of fostering this hysteria with ill-conceived initiatives, while allowing through their own negligence, catastrophic environmental events such as the recent Gulf oil spill.

Don Drumm
 

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