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BBD at 09:38 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
Natural gas is of course a fossil fuel. What interests me is the full carbon accounting for biomass, which is low energy density/high volume. - Very large volumes of biomass have to be collected (energy intensive) - Huge volumes of biomass must be transported to GT plant sites (energy intensive) EROEI? Because biofuels -
Tom Curtis at 09:37 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
Dave123, energy stored by photosynthesis is stored as chemical energy, then released as low grade heat into the environment when that stored energy is used as food. The storage is only for a short time (<1 year) on average. Because the amount released is approximately equal to the amount stored, it makes no difference to the overall budget. A very small amount of the stored energy is not released because it is gets incorporated into sediments in low oxygen environments. The lack of oxygen prevents decay, and hence the release of the energy. Overtime, and given the right conditions, that energy eventually gets turned into fossil fuels. However, given that humans are using fossil fuels at very much above the replacement rate, it follows that energy released from ancient photosynthetic storage is currently much greater than energy lost through fossilization of current photosynthetic storage. As the energy released by burning fossil fuels is inconsequential in terms of the total global energy budget, the much smaller amount lost by fossilization is certainly also inconsequential. -
WheelsOC at 09:37 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
It seems Dr. Spencer has found a hobby in making utterly terrible "models" of the climate system lately. And the funny part is that these blunders are exactly consistent with his past criticism of climate modelling:The modelers will claim that their models can explain the major changes in global average temperatures over the 20th Century. While there is some truth to that, it is (1) not likely that theirs is a unique explanation, and (2) this is not an actual prediction since the answer (the actual temperature measurements) were known beforehand. If instead the modelers were NOT allowed to see the temperature changes over the 20th Century, and then were asked to produce a ‘hindcast’ of global temperatures, then this would have been a valid prediction. But instead, years of considerable trial-and-error work has gone into getting the climate models to reproduce the 20th Century temperature history, which was already known to the modelers. Some of us would call this just as much an exercise in statistical ‘curve-fitting’ as it is ‘climate model improvement’.
So really he's only making models exactly the way he thinks they're made, by curve-fitting instead of physics, years after criticizing everyone else for allegedly doing it that way. He's both: - Consistent, because he's following the imaginary modelling procedure he outlined a couple of years ago on his blog. - Inconsistent, for whining about how wrong the models are and then turning to these same methods to seemingly prove his side of the climate manufactroversy. Tamino calls curve-fitting without physics "mathturbation." It's strange how I rarely see the "skeptics" criticizing this kind of shallow effort. Where's the Climate Auditor? -
Tom Curtis at 09:28 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
BBD @85, it is also "impossible to secure" an international network of transported nuclear fuel and waste. So, given that, what are the geopolitical risks of the widespread adoption of nuclear power in the third world? -
Dave123 at 09:24 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
Reading Trenberth and Fasulo (2011) I find myself playing catch up. My first question is whether photosynthesis is accounted for in the global energy balance. Trenberth's graph doesn't break this out, and maybe it's buried in the earlier literature. But I wouldn't on reading the chart and the accompanying text assume that the latent heat stored by photosynthesis is included. Of course, the amount could be trivial compared to the overall budget. In doing some research I've seen that claimed. According to wikipeida cyanobacteria in the ocean account for 20-30% of the photosynthetic energy at 450 TW. Using the conservative 30% (to minimize total photosynthetic energy) and 5.1E14 square meters for the earth's surface area I get nearly 3 w/m2. That seems a reasonaby large chunk given a defect error of 0.9 w/m2, and a surface absorption of 116 w/m2 according to Trenberth. My second concern to this is that I think the defect of 0.9 w/m2 has reasonably large error bars (1sd=0.5 w/m2) compared with the total budget. A 10% variation on the photosynthesis budget is a good fraction of 1 sd on the energy defect. Do cyanobacteria photosynthesie more in warmer oceans? Is there a CO2 driven increase that needs to be factored in (probably not but worth checking?) Comments? -
Tom Curtis at 09:19 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
BBD @77, it was late and I was tired, so I did not go through all the links, nor comment on any but the one post. That post contained some good advise by Hansen, and a stack of numbers use to build up emotional weight, but no analysis. Without analysis of the equivalent production commitments of continuing the current energy mix, or switching to a primary nuclear economy, the numbers cannot be analysis. They can only be an appeal to emotion as a substitute for analysis. So, how do you show the numbers to be just an appeal to emotion? By benchmarking the numbers against our current commitment in construction if we make no switch in the energy mix. Turns out, by a rough measure, the construction commitments are the same. DBDunkerson took a different rout to make the same point. Your numbers were stacked high to deflect thought rather than to aid it. The correct response it to put the discussion into terms of the proportion of world economic resources needed to make the switch, vs those for a switch to nuclear, vs continuing the current energy mix. With cited sources from the peer reviewed literature or other credible bodies. Instead you choose to dismiss our responses because we did not respond to other points you made. Well, all in good time, but your apparent inability to defend your stack of high numbers suggests that actual analysis would not bear out their visceral impression. -
dana1981 at 09:05 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
I also haven't yet seen any discussion of gas turbines, which can provide peak demand power and burn either biofuel or natural gas at relatively low cost. I think that's a key component which seems to be missing, at least from bravenewclimate. -
BBD at 08:37 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
jMurphyAnd how much damage would those "idiots" cause in a nuclear power station ?
I take your point, but what about mine: - It is impossible to secure an intercontinental network of HVDC interconnectors - It is impossible to secure a nuclear power station, but it can be made significantly more secure than interconnectors If we are concerned about security of supply, this has to be weighed. We hear nothing about it, which is surprising. -
BBD at 08:17 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
JMurphy I suspect the UK government is cosying up to the nuclear industry because there is disquiet about the emerging problems with renewables (which really means wind, in the UK). -
Stevo at 08:11 AM on 2 July 2011Google It - Clean Energy is Good for the Economy
Good article, Dana. I've long argued that by delaying action on addressing climate change our economy could miss the bus on new green technologies. Better to be at the forefront of the energy revolution than playing catchup. -
JMurphy at 08:08 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
BBD wrote : "A few (possibly suicidal) idiots with some simple explosive could cut the HVDC links at any point." And how much damage would those "idiots" cause in a nuclear power station ? More than an invasion of jellyfish ? More generally, why is the UK government cosying up to the nuclear power industry ? Can't nuclear stand on its own, without subsidy and government support all the time ? -
Trueofvoice at 07:59 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
Thanks, luminous. -
BBD at 07:58 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
Here's a general idea of how the Saharan solar concept looks on a map. -
scaddenp at 07:55 AM on 2 July 2011Increasing CO2 has little to no effect
"Model parameters can be adjusted to match any set of temperature observations" I am tired of this bit of nonsense being repeated. Show me an example of any model parameter in a GCM that is tuned to match a global temperature record. Put up or shut up. Parameterization is done inside the narrow focus of the particular response function. (eg wind speed to temperature gradient). If it were possible to "tune" parameters arbitrarily in a physics model then tell me why some skeptic hasn't produced a GCM that make CO2 irrelevant? RC regularly updated model-data comparison. Furthermore, the model archives would allow you compare prediction to actual yourself. As for updates - Hansen et al 2011 discussed in "Oceans are cooling" is certainly doing that. -
BBD at 07:51 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
dana1981 Sorry. Abrupt above. #79 You're right, I've conflated security and politics with technical possibility. Let me try again. Security and regional politics are real constraints on what is actually likely to happen. This is absolutely central to coherent policy-making. Including energy policy. Without real guarantees of security for hundreds of huge arrays in NA, presumably in remote desert locations, the Saharan solar pitch falls down. Worse by far, without real guarantees of security for every mile of cable from within NA, across Europe and to the UK, the Saharan solar pitch falls down. A few (possibly suicidal) idiots with some simple explosive could cut the HVDC links at any point. There's no engineering solution. Multiple interconnectors are disqualified both by cost and transmission loss overheads. We have to think about this. The situation in the US is different in some ways, but global strategies for decarbonisation of supply have to acknowledge this and many other problems. #80 Brook's prose style is a bit beside his point, I think ;-) As you say, there is a large amount of linked material. And you need time to read it properly. I don't expect you to mount a spirited critique just yet. Also, that's not the point. I simply wanted to provide a counterbalance to the apparently unquestioned view that renewables are going to solve the energy and climate problem. -
Stevo at 07:46 AM on 2 July 20112010 - 2011: Earth's most extreme weather since 1816?
Skywatcher @190, Yes, that was exactly how I perceived their reactions. It was easy to demonstrate the phonomenum but as soon as AGW was mentioned as being the cause I lost half of them. My guess is that if I'd mentioned AGW before demonstrating the data I'd have lost far more than half, including a few who'd have walked off just so that they would not appear to be splitting from the herd. -
Dikran Marsupial at 07:09 AM on 2 July 20112010 - 2011: Earth's most extreme weather since 1816?
Eric@196 If the variability is high, that just means that an extreme with a hundred year return time is of a larger magnitude than it will be in an area with less rainfall variability. But it is still a once in a hundred year event. If a slight variation in conditions were enough to cause an extreme, it would happen often enough that the return tiem would be less than 100 years. Extreme value theory has that sort of issue well covered. Likewise variability within an area (that would not apply to monsoon rain, but it would apply lo localised storms or convective precipitation. Again a combination of spatial statistics and EVT has this covered. -
dana1981 at 06:46 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
I have to say I haven't been impressed from what I read at brave new climate so far. Firstly, he needs to get to the damn point. If I was writing that 2 part 'cannot fix the energy crisis' post, I would have done it in about one-third the number of words in his posts. Just sayin'. As to the content, I think he's way off on the economics. He seems to grossly underestimate the cost of new nuclear power, and I also think he's way off on the future costs of solar thermal. He assumes solar thermal and nuclear power costs will decline at the same rate, but that makes no sense. Solar thermal is a relatively new technology, nuclear is not. I also think he underestimates the opportunities to increase energy efficiency. -
Camburn at 06:31 AM on 2 July 2011Ocean acidification: Coming soon
Thank you Doug. I await further explanation that is robust. -
Doug Mackie at 06:20 AM on 2 July 2011Ocean acidification: Coming soon
peter@28 Oh yes there are other impacts and we will get to them. -
Doug Mackie at 06:16 AM on 2 July 2011OA not OK part 1
Alan@15 The main source of carbon for calcification in the ocean is the bicarbonate that is already there. Figure 7.3 from the IPCC 4th Assessment Report (2007) reminds us that the oceans contain more than 50x as much carbon as the atmosphere. Later posts will relate equation 1 with the shorthand way to describe the formation of calcium carbonate ( Ca2+ + CO3 --> CaCO3). This simplified equation ignores the fact that actual calcification involves the consumption of bicarbonate and release of CO2. In order to for everyone to follow the chemical and physical processes behind ocean acidification (the goal of this series), we need to start with these individual reactions. By the end of the series, you'll find that the equations will tie in nicely with your posts. mb@21: Yes, [H+] has increased. BUT it has increased at less than purely stoichiometric calculations would suggest. We explain what that means and why it is so in future posts. Others: This is post 1 of 18. We will address your concerns. We all deride blog science. Blog science is what happens when explanations are rushed. Real science takes time to explain. As we said in the introduction, the chemistry is deceptively complex but have patience and we will get there. -
dana1981 at 06:14 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
BBD - that's because I don't think there are core engineering problems preventing renewables from providing baseload power. That's what this post was all about. Maybe your links provide a convincing case otherwise. We'll see. My point about the Sahara was with regards to the required size of land use. The long distance transmission infrastructure will be a challenge (assuming the proposed project gets off the ground). Security and politics are not technical issues, they're practicality issues. The difference between solar and fossil fuels is that once the plant is built, it simply requires upkeep, as opposed to constant drilling for new fuel. -
John Hartz at 06:08 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
NOAA now uses the phrase, "The combined global land and ocean average surface temperature..." in its monthly and annual reports on the status of the climate. Am I correct in assuming that NOAA means the temperature of the lower troposphere over the oceans when it says, "ocean average surface temeprature"? -
SNRatio at 06:07 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
If the present rather stable trend of ca 0.15 gC warming per decade continues for a few more decades, we will have a simple refutation of the lowest sensitivity estimates. And, apparently, we are far from radiation balance now. One major problem in handling sensitivity is that it behaves like a "true" random variable, seemingly with expectation and variance connected, like with the Poisson distribution. That means, among other things, that a higher "true" (expectation value) sensitivity could very possibly be associated with _more_ low-values samples than a lower sensitivity with smaller variance. And if you find out how to look for such samples, you are set up with a whole denialist cottage industry in sensitivity "estimation" - of which we may have seen the first examples. It may be viewed as kind of science-based cherry-picking. On the other hand, we may also get way too high estimates for the same reasons - which I think would be even worse. I suspect that the ocean effects are very difficult to model adequately, and with no check of them, we can't really tell how representative our sensitivity samples are. But it is always very helpful when different independent lines of evidence seem to give compatible results, as we see in this case. But it's very important not to underestimate the uncertainty involved. -
John Hartz at 05:58 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
How well do the current array of climate models address the distribution of heat within the oceans? -
John Hartz at 05:53 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
How about adding a tab to the bottom of this article that lists and links to other SkS articles directly related to this topic? -
Tor B at 05:50 AM on 2 July 2011OA not OK part 1
We know CO2-enriched sea water causes ‘seashells’ (CaCO3) to erode. link . Therefore CaCO3 + CO2 in sea water --> something that isn’t CaCO3 [solid] This suggests the possibility (reversing the arrow) that growing ‘seashells’ (CaCO3) causes the release of CO2. This may not be vigorous chemistry, but the field work supports the blog's conclusion. [Geologists approach things with a geopick or a sledgehammer.] -
Dave123 at 05:41 AM on 2 July 2011OA not OK part 1
mb... you need to keep in mind that solubility of common calcium species in water is far, far less than say, sodium Here's a quick table of solubility product constant Ksp of common species: Calcium carbonate CaCO3 3.8 x 10-9 Calcium flouride CaF2 3.4 x 10-11 Calcium hydroxide Ca(OH)2 7.9 x 10-6 Calcium oxalate CaC2O4 1.5 x 10-8 Calcium phosphate Ca3(PO4)2 1.0 x 10-26 Calcium sulfate CaSO4 2.4 x 10-5 Precipitating out CaCarbonate doesn't make it immediately available to to the species that need it. Take a look at this wikipedia article on calcium carbonate= WikiPedia Article it's relatively good except that it leaves out effect of water temperatuer on the solubility product constant- calcium carbonate is unusual in that Ksp decreases with increasing temperature. -
Albatross at 03:50 AM on 2 July 20112010 - 2011: Earth's most extreme weather since 1816?
Norman @189, I'm really busy this weekend, but for now I'll address this: "I am not trying to convince you of this, I am posting the information and asking for you to explain to me an upward trend in the data provided. If it is there, I am fine with it." I beg to differ, read JMurphy's post @191. You seem to be doing your best to dismiss the trends in extremes, or to "hide" the incline-- you'll probably deny that of course, but that is how your posts come across. Your Perth heat wave example is just the latest example of cherry picking data from one location that goes against the trend-- no problem seems to be your deduction. You will probably even be able to keep this up if you are still around in 2050, yet the climate system then will be very different from what it was 100 years before, or even from what it is now. You claim to have stumbled on the same papers that happen to appear in the NIPCC report and you claim that you only now became aware of it. Did you know that I have been into space? Claims and assertions are easy to make on the web...and after dealing with self-professed 'skeptics' for several years now please pardon my cynicism and skepticism of their claims and motives. Climate scientists and climatologists and paleo climate scientists are all too aware of variability in the historical data, and yet, surprise, surprise most of them understand that AGW is real, and that current events are unusual and they expect the climate system to respond in ways that may not be pleasant for many. In fact, research suggests that we are already very likely seeing such a transition. Any reasonable person would by now, after reading this thread understand that certain (not all) extreme/intense weather phenomena are on the increase. They would also understand that yes lo and behold there have always been extreme events, but that is not the point. And repeatedly seeking out those data which support your beliefs or go against the trend, even when said papers do not support your position, or even if they are not relevant, or if the papers' conclusions have been misinterpreted to support said position, is not 'skepticism', it is denial not skepticism.Response:[DB] An Albatross in space? Now I've witnessed everything.
It is a good thing to be wary of unsupported claims. For example, I will list 4 unsupported claims about me, 1 of which is untrue:
- My great-grandfather owned a gold mine
- I used to work for the CIA
- I have appeared on national television (NBC's the Today Show)
- I am a direct lineal descendant of Bailey's Irish Cream founder R.A. Bailey
-
BBD at 03:36 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
dana1981 Not an auspicious start. You do not so much as acknowledge the core engineering problems with renewables which effectively prevent them from displacing coal as a baseload generation technology. I'm not going further until you go back. One other thing. We are both concerned about what is technically feasible. What are the problems, in your view, with HVDC interconnectors stretching from N Africa to the UK? Further, what are the security of supply issues associated with solar installations totalling the size of Germany sited in N Africa? You are no doubt aware of what is currently happening in N Africa, and it does not encourage confidence in the potential for long-term stability in the region. Furthermore, Europe would, effectively, be at the mercy of whoever had boots on the ground in NA. If this reminds you of the current situation with oil and natural gas, it is meant to. -
BBD at 03:31 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
Tom Curtis CBDunkerson I think you may need to look at the links to Brook's analysis of the limits of renewable energy before diving straight in with an argument based on plant life-cycle or land-use. -
mb at 03:28 AM on 2 July 2011OA not OK part 1
Also, I should add that much of my previous post assumes an unlimited supply of calcium ions. So.... crush up a bunch of Tums and put it in the ocean to eat up CO2! :P -
mb at 03:23 AM on 2 July 2011OA not OK part 1
@Doug_Mackie @9 - I'm not questioning the acidification of the ocean, I'm questioning the CO2 source/sink part. As you nicely show in the final line of the orange-boxed eqns., one CO2 goes in and you get sea shells plus acid (H+)... there's no returning of CO2 to the atmosphere on the RHS of the orange box rxn set. Hence I still think the original [Eq. 1] is misleading, at best, and incorrect, at worst. To answer your question ("what do you think happens to the 2 H+?"): Hydronium in the ocean can probably react with lots of stuff. But my understanding is that there's been an observed increase in [H+] (square brackets mean "concentration" for the non-chemists out there) in the ocean. Hence, I would conclude that an increase in [CO2]{g} (ie, atmospheric carbon dioxide) is in fact driving the formation of acid (actually, H3O+). Even in the theoretically closed system of the orange box with water, CO2, & calcium ions, we must conclude that an increase in [CO2]{g} on the LHS will drive the equilibrium to the RHS. Thus, CO2{g} is being taken from the atmosphere, not to be returned (or only returned in small quantities... chemists would draw that conclusion as a big arrow pointing to the right and a small arrow pointing left). More generally, (and as has been pointed out) this discussion is somewhat without context if we don't discuss rate constants and concentrations. That said, there's not reason to believe OA is, prima facia, a carbon source. Instead, OA is a result of increased [CO2], driving the last line of the orange box to the RHS (to the acid-producing side) a-la LeChat's (ie, big arrow pointing to the RHS). (Incidentally, the orange-boxed equn. in comment 9 is missing a 2 on the first line in front of CO2). -
Camburn at 03:11 AM on 2 July 2011Websites for Watching the Arctic Sea Ice Melt
Probably the largest change in the Arctic in the past 15 years has been the amount of black carbon intertwined in the ice as a result of China's dramatic increase in coal powered power plants with what looks like no pollution controls in place. See the Shinell link I have posted. The increase in albedo means ice melting in place, or becoming so weak that it fragments very easily. As the Catlin expidition noted, the dynamics of melting ice in place changes the dynamics of water temperature as well. -
luminous beauty at 03:09 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
Trueofvoice, Understanding 'transient thermal response', in this context, is probably easiest when considering the simple model of putting a tea kettle on a stove at low heat (insufficient to reach boiling point). The transient thermal response is the differential change in temperature at any particular point in time (∆T/∆t), between putting the kettle on the stove and the final temperature when reaching an equilibrium state. As for your first question, I suspect Spencer is only considering conduction (linear diffusion between layers) in his model, i.e., treating the oceans as if they were as simple a system as the tea kettle. -
dana1981 at 02:51 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
Hi BBD. Thanks for the links, it will take me a while took look through all of those. I tend to focus on what's technically feasible, and I think 100% renewable energy by 2050 is technically feasible. What's practically feasible is another question, the main difference being the amount of effort we're willing to put into the transition, with the range anywhere from zero to WWII-style effort. Practically speaking it's going to be somewhere in the middle. However, I don't see nuclear as the solution either. In the USA, it takes 1-2 decades from conception until a single new nuclear plant is fully constructed, and new nuclear energy is currently very expensive, with costs rising as renewable costs drop. The way I see it, as current power plants age, they need to be replaced with something, and that something should be some form of renewable energy. Current coal plants can also be retrofitted to burn bio waste, as some utilities are already doing. As for land space, there's more than enough desert in Arizona to meet the USA's energy needs, and in the Sahara to meet Europe's. Of course you have to deal with long distance transmission, but I don't think land area is an issue. Plus there's offshore wind power as well. That's a major option for the UK in particular. Will be interesting to see how much offshore wind development your country goes for. -
Dave123 at 02:38 AM on 2 July 2011OA not OK part 1
Pete, Open source has the problem of what data is available, especially without scrounging. HSC has over 20000 compound and elements in its database, which is extensible. I'm sure however that open source is just fine for this case. This is rather trivial stuff. The hard part is the air/water volume assumptions you make, if you're really trying to model fluxes... and then do you partition water phases into pressure zones? My copy at this point is legacy from past employment. I keep it some statistics and graphics packages around for nostalgia's sake. I rarely use them anymore in my current roles. -
Philippe Chantreau at 02:36 AM on 2 July 2011Websites for Watching the Arctic Sea Ice Melt
Eric, Warm waters are not nearly as much of a factor for determining the minumum extent as weather patterns. The extent drops when ice is fragmented and exported South. Winds and currents do that. -
CBDunkerson at 02:35 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
BBD wrote: "Two terawatts of photovoltaic would require installing 100 square meters of 15-percent-efficient solar cells every second, second after second, for the next 25 years. (That’s about 1,200 square miles of solar cells a year, times 25 equals 30,000 square miles of photovoltaic cells.)" '100 square meters every second, second after second, for the next 25 years' Wow. That sounds bad. Except, of course, there is no logical reason that the installation would have to proceed sequentially. Instead, let's say that 1% of the people on the planet go out and install 100 square meters (i.e. 10' x 10') panels. Let's further say the installation is really slow and takes a full day. ~700,000,000 people / 86,400 seconds in a day = 8,101 panels per second Huh. That one per second thing doesn't seem quite as impossible anymore. '30,000 square miles' and 'Renewistan' Gee. That sounds bad too. Except, of course, that it is entirely possible to put solar panels on the roofs of buildings, over parking lots, on telephone poles, et cetera. Human beings are already using ALOT more than 30,000 square miles of land in ways that could be dual-purposed to also hold solar panels. -
Stephen Baines at 02:31 AM on 2 July 2011Roy Spencer on Climate Sensitivity - Again
So when will we see Spencer submit this paper to Nature, I wonder? He should be challenged to do so. If he doesn't, then I don't know why I should bother bothering about anything he writes at this point. He's entered the realm of von Daniken, IMO -- only he seems to have a cynical political motivation. -
Tom Curtis at 02:09 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
BBD @69, I'm not going to go through all those numbers. Instead, I will introduce a few of my own. You indicate in 72 that energy infrastructure has a life of "thirty years plus". The plus is not to large in that by the time a power station is thirty years old, it requires significant and ongoing refurbishment to remain efficient. So, for the sake of discussion, I will assume an average life span of thirty five years. That means that in 25 years time, 70% of our existing generation capacity will be replaced, or upgraded at a similar cost to replacement. In terms of generation capacity, that is 11.2 terrawatts, or about the capacity that you indicate needs to be replaced by renewables. At this point I don't see why I should bother going through your numbers on scale. Evidently, the scale of the task is similar to the scale of the task of ongoing business as usual. Yes, that is a huge task, but we are a busy, productive, and numerous species, and the task is not greater in scale than any we are not already committed to. -
BBD at 01:04 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
5. Conclusion - Renewables are not the correct choice for the rapid displacement of coal from the global energy mix. - Promoting renewables as the ‘solution’ to global warming is mistaken and misleading. - Advocacy pushing global energy policy in the wrong direction is dangerous. - Studies advocating a substantial expansion of renewables within the energy mix must be subject to close critical scrutiny. - A far better understanding of the limitations of renewables is required for a balanced evaluation of what contribution they can make to progressive decarbonisation of the global energy supply. -
BBD at 01:03 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
4. The UK experience so far The UK is already embarked on a huge shift toward on- and offshore wind, mandated by emissions reduction commitments set out in the UK Climate Change Act 2008. We are in the unhappy position of front-row observers as unworkable policy begins to break. For example, there is this:2010 Renewables Target Missed by Large Margin The Renewable Energy Foundation (REF) today published an Information Note on the performance of the UK renewables sector in 2010 based on analysis of new DECC and Ofgem data (see www.ref.org.uk). The work shows that the 2010 target for renewable electricity has been missed by a large margin, and confirms longstanding doubts as to the feasibility of this target, and the still more ambitious target for 2020. The key findings are: • The UK failed to reach its 10% renewable electricity target for 2010, producing only 6.5% of electricity from renewable sources, in spite of a subsidy to renewable generators amounting to approximately £5 billion in the period 2002 to 2010, and £1.1 billion in 2010. • Onshore wind Load Factor in 2010 fell to 21%, as opposed to 27% in 2009, while offshore fared better declining from 30% in 2009 to 29% in 2010. • Although low wind in 2010 accounts for some part of the target shortfall, it is clear that the target would have been missed by a large margin even if wind speeds had exceeded the highest annual average in the last 10 years. • The substantial variation in annual on-shore wind farm load factors is significant for project economics, particularly Internal Rate of Return (IRR), and future cost of capital. • Planning delays do not appear to have been responsible for the missed target, with large capacities of wind farms, both on and offshore, consented but unbuilt.* • The failure to meet the 2010 target confirms doubts as to the UK’s ability to reach the 2020 EU Renewable Energy Directive target for 15% of Final Energy Consumption, a level requiring at least 30% of UK electricity to be generated from renewable sources.
This is the sort of thing that has prompted Professor Roger Kemp to write an ominous letter to the Guardian newspaper (see original for links):What is missing is recognition of the scale of technical challenges involved in decarbonising Britain's energy supply infrastructure. The fourth carbon budget said that 60% of new cars should be electric by 2030, a figure far higher than industry's most optimistic projections. The document also planned for gas boilers to be replaced by heat pumps in 25% of houses in the same time. These represent huge engineering programmes where the solutions have to be tailored to households and geographical areas. We also need to rebuild our electricity generation and transmission infrastructure, subject of the CCC's [Committee on Climate Change] December 2010 report. In the next 20 years, the coal-fired power stations, which provided more than half our electricity last winter, will be closed. All but one of the existing nuclear stations will expire. The CCC's plans say that, by 2030, renewable energy should supply 45% of our needs, compared with 3% today. Given that energy infrastructure is designed for a life of 30 plus years, this is a massive engineering challenge. We have not run large fleets of offshore wind turbines long enough to understand maintenance needs; our experience of wave energy is restricted to a few prototypes; carbon capture has, so far, been limited to a few megawatt prototypes, not the tens of gigawatts that will be required. The CCC should be more upfront about the challenges it is creating.
Professor Roger Kemp Institution of Engineering and Technology And with Diesendorf (2010) in mind, there is more worrying news in this recent study conducted by energy consultancy Pöyry:The creation of an offshore 'super grid' and a major upgrade of energy interconnections are not the silver bullet solutions to Europe's energy needs, an independent study published by Pöyry has found. The report has found that the introduction of improved connectivity would only partially alleviate the volatility of increased renewable energy generation. In the North European Wind and Solar Intermittency Study (NEWSIS) Pöyry conducted detailed market analysis of the future impacts wind and solar energy have on the electricity markets across Northern Europe as it heads towards the 2020 decarbonisation targets and beyond. The study also concluded that weather is going to play a major role in determining how much electricity is generated and supplied to home and businesses throughout Europe, with electricity prices much lower when it is very windy, but unfortunately higher when it is still.
I could, literally, go on all day, but this should give you an idea of the way things are already starting to look rather less rosy than the advocates for wind would have us believe. As I said, we in the UK have front-row seats. You can see very clearly from them. -
BBD at 01:03 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
3. Renewable scenarios in the UK David MacKay’s Sustainable Energy – Without the Hot Air (full text; html) is excellent, although focussed on the UK. MacKay is an ardent advocate of both renewables and decarbonisation, but a critical reading of his book shows, once again, just what we are up against. Note how conservative MacKay’s still extremely optimistic scenarios look next to Jacobson & Delucchi (2010). You can get a handle on the possible ways the UK might increase the proportion of renewables here, here and here. You can decide for yourself how politically, socially and technically feasible you find the various scenarios. MacKay’s take on the bigger picture is here. MacKay is the chief scientific advisor to the UK Department for Energy and Climate Change (DECC). -
BBD at 01:02 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
2. Renewable limits Jacobson & Delucchi’s WWS proposal is a much-cited example of a number of studies claiming that very substantial contributions to the energy mix are possible from renewables. As such, it needs close critical scrutiny - under which it fails dramatically. Professor Barry Brook finds much at fault with Jacobson & Delucchi. Be sure to follow the links in Brook's review to further critiques of by Charles Barton and Gene Preston. Brook is unsparing, and rightly so:They make a token attempt to price in storage (e.g., compressed air for solar PV, hot salts for CSP). But tellingly, they never say HOW MUCH storage they are costing in this analysis (see table 6 of tech paper), nor how much extra peak generating capacity these energy stores will require in order to be recharged, especially on low yield days (cloudy, calm, etc). Yet, this is an absolutely critical consideration for large-scale intermittent technologies, as Peter Lang has clearly demonstrated here. Without factoring in these sort of fundamental ‘details’ — and in the absence of crunching any actual numbers in regards to the total amount of storage/backup/overbuild required to make WWS 24/365 — the whole economic and logistical foundation of the grand WWS scheme crumbles to dust. It sum, the WWS 100% renewables by 2030 vision is nothing more than an illusory fantasy. It is not a feasible, real-world energy plan.
Power transmission consultant Dr Preston is equally sceptical:In sum, I do not believe this is achievable at all. Therefore the concept envisioned in the SA [Scientific American] article [summarising the J&D paper inEnergy Policy] is not a workable plan because the transmission problems have not been addressed. The lines aren’t going to get built. The wind is not going to interconnect. The SA article plan is not even a desirable plan. The environmental impact and cost would be horrendous. Lets get realistic.
A summary of the constraints on a rapid increase of renewables in the energy mix is provided here: Renewables and efficiency cannot fix the energy and climate crises (part1) and (part 2). Brook and others examine the limits to renewables in greater detail in a series of twelve articles here. If you really want to understand why renewables are not going to displace coal from the global energy mix to a significant extent, the above is essential reading. -
BBD at 01:00 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
1. Context and scale Let’s start off with a reminder of what it was that James Hansen said in his letter to President Obama (emphasis added):Energy efficiency, renewable energies, and an improved grid deserve priority and there is a hope that they could provide all of our electric power requirements. However, the greatest threat to the planet may be the potential gap between that presumption (100% “soft” energy) and reality, with the gap filled by continued use of coal-fired power. Therefore it is important to undertake urgent focused R&D programs in both next generation nuclear power and carbon capture and sequestration. These programs could be carried out most rapidly and effectively in full cooperation with China and/or India, and other countries. Given appropriate priority and resources, the option of secure, low-waste 4th generation nuclear power (see below) could be available within a decade. If, by then, wind, solar, other renewables, and an improved grid prove that they are capable of handling all of our electrical energy needs, then there may be no need to construct nuclear plants in the United States. Many energy experts consider an all-renewable scenario to be implausible in the time-frame when coal emissions must be phased out, but it is not necessary to debate that matter. However, it would be exceedingly dangerous to make the presumption today that we will soon have all-renewable electric power. Also it would be inappropriate to impose a similar presumption on China and India. Both countries project large increases in their energy needs, both countries have highly polluted atmospheres primarily due to excessive coal use, and both countries stand to suffer inordinately if global climate change continues.
With Hansen’s cautionary words in mind, it’s time to start thinking about scale. Here’s Stewart Brand writing on Saul Griffith and the scale problem. Welcome to Renewistan:The world currently runs on about 16 terawatts (trillion watts) of energy, most of it burning fossil fuels. To level off at 450 ppm of carbon dioxide, we will have to reduce the fossil fuel burning to 3 terawatts and produce all the rest with renewable energy, and we have to do it in 25 years or it’s too late. Currently about half a terrawatt comes from clean hydropower and one terrawatt from clean nuclear. That leaves 11.5 terawatts to generate from new clean sources. That would mean the following. (Here I’m drawing on notes and extrapolations I’ve written up previously from discussion with Griffith): “Two terawatts of photovoltaic would require installing 100 square meters of 15-percent-efficient solar cells every second, second after second, for the next 25 years. (That’s about 1,200 square miles of solar cells a year, times 25 equals 30,000 square miles of photovoltaic cells.) Two terawatts of solar thermal? If it’s 30 percent efficient all told, we’ll need 50 square meters of highly reflective mirrors every second. (Some 600 square miles a year, times 25.) Half a terawatt of biofuels? Something like one Olympic swimming pools of genetically engineered algae, installed every second. (About 15,250 square miles a year, times 25.) Two terawatts of wind? That’s a 300-foot-diameter wind turbine every 5 minutes. (Install 105,000 turbines a year in good wind locations, times 25.) Two terawatts of geothermal? Build 3 100-megawatt steam turbines every day-1,095 a year, times 25. Three terawatts of new nuclear? That’s a 3-reactor, 3-gigawatt plant every week-52 a year, times 25.” In other words, the land area dedicated to renewable energy (”Renewistan”) would occupy a space about the size of Australia to keep the carbon dioxide level at 450 ppm. To get to Hanson’s goal of 350 ppm of carbon dioxide, fossil fuel burning would have to be cut to ZERO, which means another 3 terawatts would have to come from renewables, expanding the size of Renewistan further by 26 percent. Meanwhile for individuals, to stay at the world’s energy budget at 16 terawatts, while many of the poorest in the world might raise their standard of living to 2,200 watts, everyone now above that level would have to drop down to it. Griffith determined that most of his energy use was coming from air travel, car travel, and the embodied energy of his stuff, along with his diet. Now he drives the speed limit (and he has passed no one in six months), seldom flies, eats meat only once a week, bikes a lot, and buys almost nothing. He’s healthier, eats better, has more time with his family, and the stuff he has he cherishes. Can the world actually build Renewistan? Griffeth said it’s not like the Manhattan Project, it’s like the whole of World War II, only with all the antagonists on the same side this time. It’s damn near impossible, but it is necessary. And the world has to decide to do it. Griffith’s audience was strangely exhilerated by the prospect.
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Riccardo at 00:59 AM on 2 July 2011Websites for Watching the Arctic Sea Ice Melt
Dikran Marsupial no doubt that just two purported cycles do not make a real pattern, more so when an arbitrary underlying trend is added. We've already seen this a while ago. No physics no party, I'd say as a physicist ;)Moderator Response: [Dikran Marsupial] Absolutely, statistics can be very helpful in trying to identify the data generating process, but at the end of the day, the data generating process is what we want to understand, rather than the data. For that you need physics. -
BBD at 00:52 AM on 2 July 2011A Detailed Look at Renewable Baseload Energy
dana1981 Thanks for linking to this article and inviting me to comment. There is much to say. I dislike comments which set lots of ‘homework’ but in this case it’s unavoidable. I’ve split my response up , but I don’t know how sensitive your spamometer is to links so some of it might get filtered. -
Eric the Red at 00:26 AM on 2 July 20112010 - 2011: Earth's most extreme weather since 1816?
Dikran, WHile I agree with most of your post regarding records and extremes, I maintain that record rainfall during monsoons or tropical cyclones is tenuous. Two reason for this: 1) the amount of rainfall is highly variable such that only a slight variations in conditions (atmosperic and oceanic) are needed to create the extreme, and 2) rainfall is highly variable within the measurement area creating a larger spread in the data. These aspects are absent in other readings such as temperature. -
Pete Dunkelberg at 00:26 AM on 2 July 2011OA not OK part 1
HSC 6.15? How about open source? I'm pretty sure Dr Mackie knows of various sources for the original HCO3- in Eq 1. The point of the equation is what happens in the water column: the reaction increases dissolved CO2. Chemware @6, before saying Eq 1 is wrong think about the equilibrium constants for all the steps including CO2 exchange with air. The author probably teaches the details in Chem 1. Meanwhile think on the point of the equation.
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