Of course, I got a feeling that emissions trading was waiting just offstage. If so, before he/she is summoned it might be a good idea if the author examines the work of David Victor and Ruth Greenspan Bell, because as both of them point out there is a difference between dealing with SOx emissions and GHG emissions.

The 90% growth in nuclear share will likely generate more "slings and arrows" than any other aspect of the plan.

Ed

Instead of trying to preemptively guess the best solution, or pick technological winners, we should just enforce our intent to reduce CO2 emissions through a fair and objective tax or cap-and-trade plan, and let the market pick the approach. The article had a lot of discussion on what approaches seem most plausible now, what technology is available, what their limits are, and what various options are projected to cost, etc... That's the beauty of a simple tax or cap system. You don't have to answer, or even think about, any of those issues. You don't have to pick the winners in advance, or pre-plan how we're going to solve the problem.

BTW, it's not hard to estimate the overall cost of reductions. Unsequestered coal plants (not autos) are the lowest hanging (major) fruit. Just ask yourself, what are the non/low-emitting alternative generation options, and how much more do they cost (per kW-hr) than coal. Multiply the additional cost by coal's annual generation of ~2 trillion kW-hrs per year. Reducing CO2 emissions will involve replacing coal with these options (or sequestration), period.

Personally, I don't believe for one second that any sequestration option will be anywhere near competative with nuclear, wind, or any other non-emitting option. I could wrong, but once again, that's the beauty of it, I don't have to be right, or figure this out. Just put in CO2 limiting policies, and wait and see what happens.

Interesting approach. Don't pick winners; just pick losers and let the market sort out the winners from among the "non-losers". Sounds like a distinction without a difference to me.

1. New natural gas fired combined cycles to have heat rates around 6400 btu/kwh (HHV); 2. New flexible generators, such as the LMS 100, some in combined cycle configuration, to average heat rates around 8000 but/kwh (HHV); 3. Capacity factors of new wind generation around 35% (since the best locations are already taken); 4. Wind generation no more than 5% on heat storm peaks, as has been the case in the Pacific Northwest and California, so wind is generally not available when it is most needed, but rather when capacity is relatively plentiful; and 5. Use of flexible generation is necessary to complement wind;

the math then looks like this:

Base load generation from natural gas is 6400 btu/kwh.

Base load generation using wind is:

35% * 0 btu/kwh + 65% * 8000 btu/kwh = 5200 btu/kwh on average.

If this math holds, then wind reduces CO2 emissions by 19%, compared with base load natural gas generation.

Among other questions, we have to ask if it is physically possible to reduce the amount of natural gas generation while increasing wind generation substantially.

I hope there will be enough renewable resources that will do better than this math indicates to enable the expectations for renewables that underlie this article But with the usual heavy reliance on wind for renewables I have yet to see how renewables will do that.

With all due respect, I don't really understand what you mean. English is not my native language so please explain. :)

Your approach does not let the market sort between all choices; but, only between the choices you have not already banned. You don't pick winners, you pick losers instead. You apparently trust the market, but only just so far. Oh ye of little faith!

So let's see: you ban coal and natural gas(and, by implication, oil and corn- and cellulose-derived hydrocarbons); the enviros ban new nuclear and new large hydro; and, the wildlife advocates ban wind (dead birds, you know). That leaves solar, geothermal, OTEC, wave energy and small hydro. It may be a long, cold, dark while before the market sorts those remaining options out.

Perhaps you could also ban population growth until the winners are selected. That would save a lot of inconvenience.

It wasn't the market that gave Sweden the lowest cost electricity in the world, but a little backward induction. If you wanted low cost electricity in a world where the oil price might reach $75-100 a barrel (which was the concensus forecast after the first oil price shock), then you went into the nuclear construction business on an all-put basis.

Perhaps I should mention that the Royal Society in the UK has also come to the conclusion that sequestration is a dead end as compared to nuclear and e.g. wind. Wind of course has a lot less to offer than the TV audience has been led to believe, but since it is the flavor of the week it pays to give it a modicum of lip service.

So I say, let the market decide which of the CO2-free technologies should be used (I think it will be nuclear in most of the places most of the time). And when that has been decided State and market should cooperate to lower costs as much as possible utilising for example government loan guarantees to lower the cost of capital.

You write "you ban coal and natural gas(and, by implication, oil and corn- and cellulose-derived hydrocarbons)".

I can't see how you reach that conclusion. I don't oppose the use of oil where there is no adequate alternative, like in the transportation sector. Corn ethanol do seem pretty useless and one big subsidyfest, but why do you think I oppose other cellulose derived hydrocarbons? I don't think liqiud biofuels is _the_ solution but they can definitely be a part of the solution.

Liquid biofuels are not CO2-free, although they are not imported oil.

Of course there are some extra emissions from machines and fertilizer use, but it's a small post (except for corn ethanol and such, which I oppose).

Since the use of cap-and-trade for SOx reduction, however, some people appear to have attributed magical qualities to cap-and-trade. They seem to believe that implementing a cap-and-trade program will magically result in emissions reductions at low-cost solution.

This is part of the reason that the article was written. First, in order for any approach to achieve emissions reductions at low-cost, there need to be cost-effective emissions reduction options. This article identified some of the cost-effective emissions reductions options. These options do not appear to have been clear to many people. America appears to have been floundering because it has not been able to figure out how to reduce CO2 emissions at low cost. There don’t appear to be a bunch of different CO2 emissions reduction proposals such as the one discussed here.

The discussion around reducing CO2 emission reductions has mostly been about carbon taxes and cap-and-trade because, it appears, the alternatives for physically reducing emissions have not been clear. Even with a carbon tax or cap-and-trade, emissions still must be physically reduced. Carbon taxes and cap-and-trade can only facilitate the use of cost-effective approaches for physically reducing emissions. Thus, the alternative options for physically reducing CO2 emissions need to be explored as well as the extent that emissions could be reduced using these options.

The approach suggested in the article may achieve greater levels of emission reductions than what could be achieved with a modest carbon tax or cap-and-trade level. A carbon tax or cap-and-trade “safety-valve” has often been discussed in the range of $10/ton of CO2. This may not be enough of an incentive to achieve the level of reductions discussed in the article. For example, a national renewable portfolio standard might achieve greater level of renewable construction and, therefore, emissions reductions, than a $10/ton CO2 tax. Also, a carbon tax or cap-and-trade might not achieve as great an emissions reduction as a CAFE standard. A combination of a carbon tax or cap-and-trade program in conjunction with a national renewable portfolio standard and a CAFE standard may be the approach to achieve high levels of emission reductions.

The approach proposed in the article may also result in lower cost to utility customers. For example, if a $10/ton carbon tax were instituted, it would translate into about a one cent per kWh increase in rates for customers at a utility that used mostly coal-fired generation and some gas-fired. If the approach in the article was used, renewable generation could be added to displace the coal- and gas-fired generation without significantly increasing the rates to the utility customers.

It is not clear that emissions reductions would be achieved by a carbon tax. Some proposals have funds going to R&D or various other places.

The level of emissions reduction that can be achieved with different technologies also needs to be explored in order to determine a realistic cap. The Kyoto Protocol cap of 7% below the 1990 emissions level by 2012 was not realistic. This study (and sensitivity cases around it) indicates that achieving the Kyoto Protocol emissions level for the U.S. prior to about 2030 would be difficult or expensive. Other potential caps would also need to be evaluated.

Carbon taxes or cap-and-trade are obviously approaches to consider rather the command-and-control or government incentive approach implied in the article. Carbon taxes and cap-and-trade may be able to replace some of the incentives discussed in this article. For example, instead of the US government continuing the Production Tax Credit (PTC) for renewable generation, a carbon tax or cap-and-trade might be a source of incentives for renewables.

Global Insight is currently conducting a study of carbon taxes and cap-and-trade. It will be interesting to see how their carbon tax and cap-and-trade results compare with their command-and-control scenario and the Low-Cost Scenario presented here.

Base load generation using wind is: 35% * 0 btu/kwh + 65% * 8000 btu/kwh = 5200 btu/kwh on average. If this math holds, then wind reduces CO2 emissions by 19%, compared with base load natural gas generation. - Dick Maclay, 10.5.06

Where the subtlety comes in is in the definition of “rated capacity”. Consider this: it’s trivially easy to double the capacity factor for a wind turbine. All you have to do is scratch out the rated capacity on the nameplate, and write in a new value that’s half as large. Voila! CF, the ratio of average output to rated output, is instantly doubled!

Of course, with no other changes, your turbine has acquired the interesting characteristic that under strong wind conditions, it is capable of functioning in “overload” at twice its rated output. Is there a problem with that? It’s not a trivial question.

The answer is that in the large majority of cases, it won’t be a problem. So your wind resource is delivering above its rated output? Well, most of the time, the system load will be sufficiently above its minimum baseload value for that to be just dandy! You’ll simply leave off more of the dispatchable capacity that you’d otherwise be running.

Occasionally, wind output will be above rated capacity at a time when demand is so low that in order to accept the excess output, it would be necessary to shut down baseload generating units (assuming you even have any). That’s a definite no no. Hence, in that case, your SCADA system just tells the wind resource to go screw itself—you’re not going to accept its "overload" output.

That’s perfectly OK. From a physical point of view, it’s no problem to tap less of the wind’s energy that your turbines are capable of tapping. It just means letting the wind pass with less hinderance. Of course, you have to make sure that the control system is designed to allow it. The economic impact from rejected capacity will be minor, since it will rarely be necessary.

The other flaw is in the assumption that the combination of wind + flexible power would be used to supply base load. There will be an increasing trend toward responsive loads that can operate when power is available. For responsive loads, the need to have flexible capacity to back wind resources is avoided.

Bottom line: the amount of dispatchable (flexible) generating capacity required to back wind power can be quite a bit less than you would estimate from the nominal capacity factor, and the average contribution of wind power can be larger than its average capacity factor. The constraints for that are: (1) when there's no call for it, you can cut back excess wind generation to match demand; or (2) you have responsive loads sufficient to insure that there's always a call for whatever wind generation is available.

This wealth transfer is coming from both developed countries (how much of the US trade deficit is down to oil imports rather than an undervalued Chinese currency?), and developing Asian economies (notably the 2 billion or so hard-working farmers of the region). This wealth is going to those who perhaps deserve it least - the excessively wealthy Mid-Eastern producers and oil company shareholders: There was more than one reason for Kyoto.

I'm all for nuclear power, and other renewables, but the mechanisms must be in place to encourage investment in them and motivate developing countries to do the same, which necessitates some form of carbon market.

Prof Banks - as you probably know my company predicts a steady rise in oil production and a sharp rise in gas production over the next few years, based on a bottom-up analysis of the most comprehensive oil and gas database in the world. Of course oil is a finite source, but there's plenty left and no peak in sight, certainly not at current prices. Technology can change the 'peak' scene completely (as it has done many times when energy insecurity or high hydrocarbon prices allocate investment 'efficiently'). I doubt the Japanese would have gone to war in 1942 had they known vast reserves of oil and gas existed in Japanese (at the time) Sakhalin and occupied China (Daqing). Geopolitics can also alter the baseline, although neither factor can be built into models. There's probably a great deal of oil and gas in the seas surounding N Korea, but who is to know what will happen there next.

Given the ample oil, gas and coal resources in the world, it is essential that something is done to stop their exponential exploitation - to stop unjust wealth transfer/concentration, global warming and geopolitical instablility.

A carbon market is needed, but one that is designed to avoid the excesses and social injustice that markets can generate (perhaps a market encorporating S-curves, rolling averages, floors and ceilings for example). It must also encourage developing nations to adopt renewables, as well as raising the cost of CO2 emissions if hydrocarbon prices fall.

1) You say that nuclear is economic, in part "because of the incentives in EPAct". I agree, but the caveat deserves more merit. As a colleague once told me, "no economically rational individual has ever built a nuclear power plant". These are huge subsidies and insurance waivers, which society ultimately pays for. I agree with you that nuclear has to play a role in a carbon-constrained future, and there is a legitimate line of questioning that we ought to commence to try and flesh out how much benefit we get from zero-carbon nukes, and whether that justifies the corresponding cost. But until proven otherwise, we should not assume that greater nuclear penetration is economically viable.

2) You limit your discussion of energy efficiency to "electricity consuming equipment". This is narrow, and leaves the lowest hanging fruit unplucked. The electric sector is the only major CO2 source that was more efficient in 1920 than it is today (indeed, by a factor of 2). Driving efficiency levels back to the 1920s (and dare I dream, beyond?) would have an enormous impact on carbon emissions and boost the economy, although it will require massive regulatory changes to correct the throughput bias of regulated utilities. However, it's the only significant carbon reduction strategy that does not require additional cost, and deseves inclusion in your model & recommendations.

"Given the ample oil, gas and coal resources in the world, it is essential that something is done to stop their exponential exploitation - to stop unjust wealth transfer/concentration, global warming and geopolitical instablility."

If Kyoto could have accomplished all of this, it might almost have been worth the cost. However, unjust wealth transfer, global warming and cooling and geopolitical instability pre-existed the discovery of oil and will continue beyond its total depletion. (Some might argue that today's instability is more geo-religious in nature.)

If resource poor countries wish to sever their dependence on oil, why can't they just do so without the benefit of some massive, worldwide "kumbaya"-fest? The technology is arguably available. Some would even argue it is cost competitive.

It is also important to remember that Kyoto (no matter how many reasons there were for it) was not ever intended as the be-all and end-all of the "war against AGW". It was and is only step one in a process which, at least publicly, is not clearly defined. This lack of candor regarding future reductions has the potential to lead to massive investments in technologies which are not on the path to the ultimate reductions required.

As for the reason why the Japanese went to war, I have studied this at great length over the years, beginning with a long tour of duty in Japan with the US army. They went to war because they thought that they could give Uncle Sam a good beating. This kind of thinking would have made a great deal of sense if the US had been a Fourth World country, but unfortunately for them this was not the case.

I'm sure that you and your colleagues are very competent at forcasting future oil production, but I would like to assure you that while a few firms might make a lot of money producing oil in and around East Asia, this will NOT change the world oil picture. Furthermore, the OPEC countries are now making enough money so that they can forget about things like repaying the money that they have borrowed, and can and concentrate on conservation. I wont bother going into what this will mean, but it definitely isn't good news for those of us on the buy side of the market.

As for Sean Casten's observation about the irrationality of investing in nuclear, I think that everybody in the world except the ignoramuses teaching economics in Sweden are capable of understanding that the Swedish nuclear sector received NO subsidies. Once again, much or most of that sector was financed by taxes, and the money received from taxpayers (in the aggregate) was returned to them in the form of the greater income and welfare that resulted from the availability of relatively cheap, nuclear based electricity. And it was returned with interest, I might add.

I had one more comment, which was about emissions/carbon trading, but as it happens I haven't had my dinner yet, and if I did more than mention it I would probably lose my appetite. But I can note that I asked one of my former students, now teaching in the US, what he thought about it - if he thought about it at all. "Just another scam", he said, thereby proving that while the academic economists in this country hardly deserve to be called dunces, we still have the best students.

An ex-nuclear engineer

I agree that carbon markets will find low cost and even profitable ways to reduce GHG and that the eight areas discussed can each contribute. However, the article makes the widely held, seldom questioned assumption that electric generation is optimal. This assumption is the achilles heel of energy policy all over the globe. The US system delivers only one third of the energy it consumes as useful kWh, and cannot recycle the by-product thermal energy because of our reliance and regulatory support of central, remote generating plants. A recent EPA study identified industrial waste energy streams capable of powering 64,000 megawatts of new capacity and generating 20% of US power. Every kilowatt of this capacity would have to be located at the site of the waste energy creation -- at steel mills, chemical plants, refineries, at every natural gas pipeline compressor station, at every steam and gas pressure reducing point. Recycling industrial waste energy would not cause any incremental fossil fuel or incremental GHG, and can be done at $20 to $50 per megawatt-hour, all in. by contrast, the delivered price of power, incuding new T&D investment amortization and line losses, will range from $100 per mWh for new conventional coal plants with full scrubbing, from new CCGT's burning natural gas and from wind farms. New coal that sequesters CO2 will need about $170 per mWh (17 cents per delivered kWh) and new solar clocks in at about $240 per mWh. There are many reasons why the power industry has failed to embrace local generation that recycles energy. Even though CHP plants fueled by natural gas and based on industrial gas turbines, just like remote CCGT plants, can deliver new power at $50 to $60 per mWh, the industry keeps developing remote plants. Industrial plant managers concentrate intellectual and financial resources on core activities and regularly ignore opportunities to recycle waste energy that have 1 to 3 year paybacks. Why? The answer, in a word, is regulations. The system is deeply biased towards central generation. The utilities that distribute power profit from throughput on those wires and naturally oppose all local generation. The developers of recycled energy projects are unable to capture much of the value their projects create. For example, a new renewable energy project is considered 'green' and can sell green tags or 'renewable energy credits' for $10 to $15 per mWh. Recycling industrial waste energy is just as green, but does not qualify for the REC or green tag. Recycling waste energy creates electricity at the point of use and lowers the need for new T&D, lowers the line losses on existing loads (losses are related to the square of the current flow, so lower current cuts losses by the square), but recycled energy projects are not paid for these savings to the other customers.

The net result is that recycled energy projects are seldom developed, and society falls back on the default position -- build new transmission and distribution facilities, which are essentially guaranteed, since they go into rate base. Then build new central generating facilities, which even though unable to compete with recycled energy on cost, are built anyway, since regulations block this vital form of competition.

Anyone interested in a more complete explanation, go to www.primaryenergy.com and look at the articles on recycled energy

Thomas R. Casten Chair and CEO of Primary Energy Ventures.

First, the economics of wind are based on full rated output, so any arbitrary derate would make the economics of wind look bad. That is just trading one downside for another.

The actual patterns of electric demand and wind generation in California and the Pacific Northwest of the U.S. turn out to be opposed. Wind generation falls to 4% to 10% of full capacity when electric demand is highest (no where near 50%), and wind generation peaks when demand is falling. So basing the contribution of wind on a base load comparison is generous. In that regard, I intentionally built in a flaw, but one that was designed to favor wind.

You are perfectly correct that IF we can move demand from peak periods to periods when the wind blows that will make wind more valuable. Doing so on any scale will have a cost, though moving air conditioning loads with thermal storage may have sufficient advantages in reducing the need for wires to make that cost reasonably low. However, the lessons learned across the U.S. in 2006 was that demand is becoming more peaked each year, not less, and demand reduction programs are less effective than expected, especially during long heat spells.

A reliable way to find out how much load can be shifted is to allow price swings during the day to fully reflect relative supply and demand. Half of the electric load in the U.S. has been on interval meters for decades, but political influence has not allowed prices to reflect the diurnal cycles of supply and demand. It is unlikely that economic incentives to fit electric demand to wind’s supply will appear any time soon.

A combination of wind and solar would be better balanced, but we can’t afford enough solar with current technology to make that balance matter.

It remains difficult to see how wind and solar will have a significant impact on GHG, at least how it can be done without major changes in retail electric price signals.

Though I was kind of negative on cap-and-trade in the article, one of the great advantages of cap-and-trade over a prescriptive apporach is that it can draw out "unexpected" emissons reduction options like industrial CHP. If cap-and-trade is structured so as to give emissions credits for use of industrial CHP (or even residential or commercial CHP), cap-and-trade can provide incentives for more projects like Mr. Casten's.

Mr Reid, I agree with you completely on Kyoto not being the be-all and end-all. However, it was at least a first step, and further steps have largely been stymied by the shameful failure of the current US government to ratify its obligaitons. Without the US on board more enlightened countries have one hand tied behind their backs, making it difficult to take further steps, and to provide a united front to address the challenges in taking those steps.

And yes, I also agree that geopolitics has to some extent become geo-religious (or religion has been hijacked by populist politicians) - at least in the US and Middle East, much to the dispair of many European and other countries. It constanly frustrates me to see American evangelical preachers tramping around SE Asia (picking up where many Europeans left off, although the new brand of Christian preaching appears more fundamental), patronizing local populations with their condescending tones (shouted loudly in English) and disrespect for deeply held regional spiritual beliefs.

As for Kyoto, it should never have taken place. I don't agree with the anti-global warmers about much, but on that point they were absolutely correct. If the delegates to that travesty had been serious people, this 'emissions trading' scam would never have been launched, and the "clever economists" that you refer to might have found something that works. And here of course the issue is time. In the long run more nuclear and a lot more renewables (of all types) strike me as the way to go, but if the long run is too long, the Reeperbahn and Canal Street might end up under water.

You also say that OPEC wants to target the oil price at $50-60/b. That certainly sounds reasonable to me, but I am not sure that they can do this. If conservation has become a major element in their thinking, then I don't see how this is possible. I guess that we'll just have to wait and see here.

And incidentally Jeremy, emissions trading is not for the real world. It's for the economics seminars that nobody goes to and the learned journals of economics that nobody reads - and in this case I am once again referring to "clever economists", although I aint seen many of them lately.

Fred

This energy comparison is a little crude, but having run dispatch models of the western interconnect my intuition is that it is close to the mark. Wind generation has created minimum generation problems at night when it contributes energy before, and that will be avoided in the future only by builing less efficient gas powered generation than we would without wind generation.

If we could move a big chunk of air conditioning load to nights that would help, and with economic price signals that could happen. We would get cool storage, which can be economic. But that requires junking several decades of regulatory pricing in favor of pricing that reflects supply and demand. You did not address that in your article.

Think of a regional balancing area with no wind power. It has a certain baseload generating capacity that is necessarily less than the minimum off-peak load. It has dispatchable generating capacity consisting of a mix of generating resources that may range from multi-turbine coal-fired plants to shiny new single-cycle gas turbine units with a 38% thermal efficiency, to old standby units that get maybe 25% efficiency and run for less than 100 hours per year. The agregate capacity of these dispatchable units is probably somewhat more than double the capacity of the baseload units, since the highest load peaks are about three times the minimum off-peak load.

Now take this same system, and add wind farms. When there is very little wind, the system operates just like it did before the wind farms were there. When the wind is blowing, then power from the wind farms displaces power from dispatchable units that are left off. Naturally, the units that are chosen to be left off will be those with the highest marginal generating costs--the dirtiest and least fuel-efficient. So one kilowatt-hour of wind energy displaces one kilowatt-hour of generation from the least efficient generators that would otherwise be running; about 11,000 Btu / kWh, if I'm not mistaken.

End of story. Capacity factor has nothing to do with it, other than figuring in to the number of kWh produced per turbine, and hence the amortized cost per kWh.

The only solution is to not build new new base load facilities that could not be operated due to minimum load problems and pritority of wind dispatch. Instead build new flexible generation. The dispatch order is as you described, but the ratio of base load to dispatchable generation is affected by the construction of large amounts of wind power. Capacity factor describes the energy generating ability over time, so it has everyting to do with this condition once we recognize that the choice during far off-peak periods is between base load fossil or wind.

I spent years in utility capital planning and did modeling of these systems. The problem I describe is not theoretical. It has happened and it will happen again. Politically motivated agencies chose not to recognize this bit of reality, but that does not change reality.

Those 11,000 btu units are no longer in service in the capital planning horizon in California. They are being replaced with new plants that meet enviromental requirements. Therefore, the proper comparison is between new base load units and new flexible units. That is why I used that comparison. In the Pacific Northwest and other locations the availability of wind generation and minimum loads may not be so well corelated as in California. Problem is that we don't know because there is a strong political desire not to know. We do know the wind is not present on the largest peaks in the Pacific Northwest - which are now moving from winter to summer. We also know that even in Great Britain the winter peak is being replaced with a summer air conditioning peak. So the world may be coming to the problems with wind generation that first emerged in California in the 1970s. Without real informaiton about the correlation of wind and load we are left belileving that if the answers were reasonably favorable to wind there would not be so much reluctance to demonstrate the real correlations.

One question: in bringing up the “minimum generation” problem, are you assuming that wind resources must always be given priority for generation? That a wind farm simply dumps whatever output it has onto the grid, and that it’s then up to the TSO to accommodate it as if it were a variable load?

If that was ever the case with wind generation, I can certainly see how it would have caused headaches. But I can’t imagine that it’s true today. There’s no sound technical reason that a wind farm’s output shouldn’t be under the TSO’s SCADA control.

A wind farm can never generate more than what wind conditions of the moment allow, but it can always generate less. It can be commanded to ramp its output up or down, to match the ramp rates for dispatchable units coming on or going off line. Or it can be commanded to hold a steady output at some level safely below the maximum level that it could generate. That allows it to give advance warning of falling output, when the margin between its maximum potential output and its commanded output is falling. The downside, of course, is that some percentage of potential generation is wasted, for the sake of making the wind farm a better “grid citizen”.

The recent deal between VRB Power and the developers of the Sorne Hill wind project in Ireland is interesting in that light. The Vanadium redox flow battery that VRB Power will be installing--while large--is only good for 20 minutes of rated output from the wind farm. That’s not sufficient for outright load shifting, but it’s enough to “firm up” the wind farm output while allowing all of its available output to be utilized. When available output exceeds the commanded output, the excess goes into the battery. Stored energy is tapped later, when available output falls below the commanded output. The battery system will even allow the wind farm to supply regulation for grid stabilization.

Now that the Sorne Hill project has “broken the ice” for large scale battery storage, we’ll probably be seeing similar deals announced for other large wind projects.

One final note regarding the minimum generation problem. As I’m sure you’re aware, the trajectory for CT generation technology is blurring the lines between base load capacity, intermediate capacity, and peaking capacity. Browsing the web sites for GE and Siemens recently was eye-opening for me. They have simple-cycle units with efficiencies that once required combined-cycle operation, and advanced combined-cycle units with thermal efficiencies of 60%--half again the 40% that I still think of as characteristic of “advanced” CTCC units. All of them are apparently being designed for better resistance to cycling stress and for faster ramping.

It looks like both companies support non-integrated CC operation as well. That enables the exhaust streams from multiple simple-cycle CTs to fire a common boiler for multiple steam turbines. As long as one CT-ST pair remains in operation, additional pairs can be quickly started up or shut down, without cycling the boiler. That gives dispatchable capacity that’s every bit as efficient as baseload capacity, largely eliminating the minimum generation problem. What’s left is “just” the economic issue of return on assets. And that can only be helped by introduction of responsive loads and measures that help to reduce the spread between peak and off-peak loads.

See the gold standard 2003 MIT report re economics of new nuclear plants in the US:

http://web.mit.edu/nuclearpower/

Also, Roger Arnold's comments re wind power match my understanding, though he goes much further (which is very helpful). What he and Dick don't discuss is the possibility of firming wind power with other renewables, such as geothermal, biomass or hydro (baseload renewables). By matching different renewables, we can probably achieve substantial firm capacity.

Additionally, utility scale solar (concentrating solar power) has been used reliably for peak capacity for 20 years in California. The SEGS plants near Barstow provide 80% solar power and 20% natural gas power, with 108% production of nameplate capacity over 20 years.

First, the plan you describe discusses 2030 for reaching the Kyoto goals. Every analysis I've seen supports the view that the Kyoto 2012 goals are just the jumping off point for much more serious reductions. The UN's FCCC (the underlying treaty for the Kyoto Protocol) has now set as its end goal an 80% reduction of GHGs by 2050. By reaching for the 2012 goals by 2030, your plan would not do anywhere near as much as needs to be done to mitigate climate change. We need much more.

Second, you give short shrift to energy efficiency (or more accurately, the Global Insight study does). Energy efficiency has tremendous potential - cost-effectively - in the US. Far more than you describe. And investing billions in nuclear power, a far less cost-effective solution, would seriously detract from investments in more desirable alternatives such as energy efficiency. And of course energy efficiency improvements are equivalent to baseload generation - and can even be designed to reduce peak capacity needs with the right incentives.

The MIT report assumes absurdly low fossil fuel prices, especially for natural gas. IIRC even their "high case" is way below current prices. If current prices are used nuclear power becomes very profitable also in the MIT study.

Furtermore I think the MIT study only use a 40 year plant lifetime, instead of the currently accepted 60 years.

By the way, the 60, or even 30, year perspective is important and utilities don't consider it enough. I mean, how can you with any security forecast gas prices for your brand new 500 MW gas plant for the next 30 years? You can't. You can't forecast and you can't hedge. The same goes for coal.

With nuclear power this is not an issue as the price of uranium is in practice irrelevant to the price of nuclear electricity.

My analysis is based on the latest technology from GE, The H generation of combined cycles for base load and the LMS 100 for cycling. The H units are industrial units with steam cooling. They take hours to start up. In short, they are not flexible beyond the typical 50% turn down capability of combined cycles. The LMS 100 is an aero derivative, so it is completely flexible. But the LMS 100 uses more fuel the the H unit, even if the LMS 100 is used in combined cycle configuration.

The turn down capability of H units would seem to mitigate my analysis, but it is already fully utilized to meet the range between minimum loads and peak loads. On the margin, there is nothing left here. Similarly, hydro peaking is already fully used to meet load variations. There is nothing left for mitigating the problems created by wind generation.

Grouping combined cycles and using output of one to keep another hot when off could streatch flexibility of the combined cycles. But that costs, and it is not proven to be reliable. And there are no incentives for merchant combined cycles to do things like this in the present pricing mileu. It would require much larger diurnal variations in wholesale price to encourage this sort of thing, and that is politically difficult at best. Of course, greater dirunal price variation would reduce revenue to wind, exposing the limited economic value of a resource with a negative contribution to capacity.

Tam Hunt notes that solar generation complements wind, reducing the need for flexible fossil generation to complement wind. The problem is that photo voltaic is no where near economic, and we cannot afford to subsidize enough of it to matter to wind generation. If the developer of solar thermal generation in California demonstrates that it is reasonably economic, that will mitigate the problem I described to some as yet undetermined degree. Lets hope some form of solar power will emerge to make wind more viable.

Of course cheap wind power would encourage shifting load, especially air conditioning load (using cool storage) to periods when wind generates. But that will only work if larger diurnal price variation reaches retail customers. Maybe someday....

The point I would dispute with the pro-nuclear camp is that it's necessary. I'm convinced that renewables can do the job, albeit at higher cost with more environmental impact than a rational nuclear program would entail. But if a rational nuclear program is not in the cards, we need to figure out how to make renewables as efficient as possible.

Speaking of efficiency, your comment that "Sean Casten has it exactly right" made me scroll up to find what he had said. What on earth was he talking about when he wrote "The electric sector is the only major CO2 source that was more efficient in 1920 than it is today"? By what measure of efficiency? Coal-fired generators of that era, if I recall my industrial history correctly, had thermal efficiencies well under 10%. A quarter or less than what they are today.

Perhaps hydroelectric power was so predominant in that era that CO2 emissions were lower, relative to total energy generated. That's hardly a fair comparison, though. For better or worse, we've long outgrown the ability of hydroelectric power to supply our electricity needs.

"The UN's FCCC (the underlying treaty for the Kyoto Protocol) has now set as its end goal an 80% reduction of GHGs by 2050." To take that one step further, the end goal would require a US reduction closer to 95%. (NOTE: "A goal without a plan is just a wish.", Antoine de St. Exupery)

Once you accept the requirement of a 95% reduction in CO2 emissions (For the record, I don't.), it becomes obvious that many of the approaches proposed for achieving interim reductions are not on the path to the ultimate reductions. It also becomes obvious that the "required" reductions will be neither cheap nor easy, as Senators McCain and Lieberman suggested their interim reduction would be.

Tam's candor regarding the "ultimate solution to the AGW problem" brings to mind a quote from my favorite American philosopher, Yogi Berra: "You've got to be careful, if you don't know where you're going, because you might end up someplace else."

More efficient fossil-fueled equipment is clearly not on the path to a 95% reduction in US CO2 emissions. Rather, it is an example of beginning vast programs with half-vast ideas.