Arguments
Can renewables provide baseload power?
What the science says...
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Although renewable energy does not necessarily need to provide baseload power in the short-term, there are several ways in which it can do so. For example, geothermal energy is available at all times, concentrated solar thermal energy has storage capability, and wind energy can be stored in compressed air. |
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Climate Myth...
Renewables can't provide baseload power
Does Renewable Energy Need to Provide Baseload Power?
A common myth is that because some types of renewable energy do not provide baseload power, they require an equivalent amount of backup power provided by fossil fuel plants. However, this is simply untrue. As wind production fluctuates, it can be supplemented if necessary by a form of baseload power which can start up or whose output can be changed in a relatively short period of time. Hydroelectric and natural gas plants are common choices for this type of reserve power (AWEA 2008). Although a fossil fuel, combustion of natural gas emits only 45% as much carbon dioxide as combustion of coal, and hydroelectric is of course a very low-carbon energy source.
The current energy production structure consists primarily of coal and nuclear energy providing baseload power, while natural gas and hydroelectric power generally provide the variable reserves to meet peak demand. Coal is cheap, dirty, and the plant output cannot be varied easily. It also has high initial investment cost and a long return on investment time. Hydroelectric power is also cheap, clean, and good for both baseload and meeting peak demand, but limited by available natural sources. Natural gas is less dirty than coal, more expensive and used for peak demand. Nuclear power is a low-carbon power source, but with an extremely high investment cost and long return on investment time.
Renewable energy can be used to replace some higher-carbon sources of energy in the power grid and achieve a reduction in total greenhouse gas emissions from power generation, even if not used to provide baseload power. Intermittent renewables can provide 10-20% of our electricity, with hydroelectric and other baseload renewable sources (see below) on top of that. Even if the rapid growth in wind and other intermittent renewable sources continues, it will be over a decade before storage of the intermittent sources becomes a necessity.
Renewable Baseload Energy Sources
Of course in an ideal world, renewable sources would meet all of our energy needs. And there are several means by which renewable energy can indeed provide baseload power.
Concentrated Solar Thermal
One of the more promising renewable energy technologies is concentrated solar thermal, which uses a system of mirrors or lenses to focus solar radiation on a collector. This type of system can collect and store energy in pressurized steam, molten salt, phase change materials, or purified graphite.
The first test of a large-scale thermal solar power tower plant was Solar One in the California Mojave Desert, constructed in 1981. The project produced 10 megawatts (MW) of electricity using 1,818 mirrors, concentrating solar radiation onto a tower which used high-temperature heat transfer fluid to carry the energy to a boiler on the ground, where the steam was used to spin a series of turbines. Water was used as an energy storage medium for Solar One. The system was redesigned in 1995 and renamed Solar Two, which used molten salt as an energy storage medium. In this type of system, molten salt at 290ºC is pumped from a cold storage tank through the receiver where it is heated to about 565ºC. The heated salt then moves on to the hot storage tank (Figure 1). When power is needed from the plant, the hot salt is pumped to a generator that produces steam, which activates a turbine/generator system that creates electricity (NREL 2001).
Figure 1: Solar Two Power Tower System Diagram (NREL 2001)
The Solar Two molten salt system was capable of storing enough energy to produce power three hours after the Sun had set. By using thermal storage, power tower plants can potentially operate for 65 percent of the year without the need for a back-up fuel source. The first commercial concentrated solar thermal plant with molten salt storage - Andasol 1 - was completed in Spain in 2009. Andasol 1 produces 50 MW of power and the molten salt storage can continue to power the plant for approximately 7.5 hours.
Abengoa Solar is building a 280 MW solar thermal plant in Arizona (the Solana Generating Station), scheduled to begin operation in 2013. This plant will also have a molten salt system with up to 6 hours worth of storage. The electrical utility Arizona Public Service has contracted to purchase the power from Solana station for approximately 14 cents per kilawatt-hour.
Italian utility Enel recently unveiled "Archimede", the first concentrated solar thermal plant to use molten salts for both heat storage and heat transfer. Molten salts can operate at higher temperatures than oils, which gives Archimede higher efficiency and power output. With the higher temperature heat storage allowed by the direct use of salts, Archimede can extend its operating hours further than an oil-operated solar thermal plant with molten salt storage. Archimede is a 5 MW plant with 8 hours of storage capacity.
In southern Spain, the Gemasolar plant opened in 2011. It produces 19.9 MW, or approximately 110 gigawatt-hours per year. Gemasolar stores energy in molten salt for up to 15 hours, and is thus able to provide energy 24 hours per day for a minimum of 270 days per year (74% of the year).
The National Renewable Energy Laboratory provides a long list of concentrated solar thermal plants in operation, under construction, and in development, many of which have energy storage systems. In short, solar thermal molten salt power storage is already a reality, and a growing resource.
Geothermal
Geothermal systems extract energy from water exposed to hot rock deep beneath the earth's surface, and thus do not face the intermittency problems of other renewable energy sources like wind and solar. An expert panel concluded that geothermal sources could produce approximately 100 gigawatts (GW) of baseload power to the USA by mid-century, which is approximately 10% of current US generating capacity (MIT 2006). The panel also concluded that a research and development investment of less than $1 billion would make geothermal energy economically viable.
The MIT-led report focuses on a technology called enhanced or engineered geothermal systems (EGS), which doesn't require ideal subsurface conditions and could theoretically work anywhere. installing an EGS plant typically involves drilling a 10- to 12-inch-wide, three- to four-kilometer-deep hole, expanding existing fractures in the rock at the bottom of the hole by pumping down water under high pressure, and drilling a second hole into those fractures. Water pumped down one hole courses through the gaps in the rock, heats up, and flows back to the surface through the second hole. Finally, a plant harvests the heat and circulates the cooled water back down into the cracks (MIT 2007).
Currently there are 10.7 GW of geothermal power online globally, with a 20% increase in geothermal power online capacity since 2005. The USA leads the world in geothermal production with 3.1 GW of installed capacity from 77 power plants (GEA 2010).
Wind Compressed Air Energy Storage (CAES)
Various methods of storing wind energy have been explored, including pumped hydroelectric storage, batteries, superconducting magnets, flywheels, regenerative fuel cells, and CAES. CAES has been identified as the most promising technology for utility-scale bulk wind energy storage due to relatively low costs, environmental impacts, and high reliability (Cavallo 2005). CAES plants are currently operational in Huntorf, Germany (290 MW, since 1978) and Macintosh, Alabama (110 MW, since 1991). Recently this type of system has been considered to solve the intermittency difficulties associated with wind turbines. It is estimated that more than 80% of the U.S. territory has geology suitable for such underground storage (Gardner and Haynes 2007).
The Iowa Stored Energy Park has been proposed to store air in an underground geologic structure during time periods of low customer electric demand and high wind. The project is hoping to store a 20 week supply of compressed air and have approximately 270 MW of generating capacity. The project is anticipated to be operational in 2015.
A similar system has been proposed to create a wind turbine-air compressor. Instead of generating electricity, each wind turbine will pump air into CAES. This approach has the potential for saving money and improving overall efficiency by eliminating the intermediate and unnecessary electrical generation between the turbine and the air compressor (Gardner and Haynes 2007).
Pumped Heat Energy Storage
Another promising energy storage technology involves pumping heat between tanks containing hot and cold insulated gravel. Electrical power is input to the system, which compresses/expands air to approximately 500°C on the hot side and -150°C on the cold side. The air is passed through the two piles of gravel where it gives up its heat/cold to the gravel. In order to regenerate the electricity, the cycle is simply reversed. The benefits of this type of system are that it would take up relatively little space, the round-trip efficiency is approximately 75%, and gravel is a very cheap and abundant material.
Spent Electric Vehicle (EV) Battery Storage
As plug-in hybrids and electric vehicles become more commonplace, the possibility exists to utilize the spent EV batteries for power grid storage after their automotive life, at which point they will still have significant storage capacity. General Motors has been examining this possibility, for example. If a sufficiently large number of former EV batteries could be hooked up to the power grid, they could provide storage capacity for intermittent renewable energy sources.
100% Energy from Renewables Studies
A few studies have put forth plans detailing exactly how we can meet 100% of global energy needs from renewable sources.
Energy consulting firm Ecofys produced a report detailing how we can meet nearly 100% of global energy needs with renewable sources by 2050. Approximately half of the goal is met through increased energy efficiency to first reduce energy demands, and the other half is achieved by switching to renewable energy sources for electricity production (Figure 2).
Figure 2: Ecofys projected global energy consumption between 2000 and 2050
Stanford's Mark Jacobson and UC Davis' Mark Delucchi (J&D) recently published a study in the journal Energy Policy examining the possibility of meeting all global energy needs with wind, water, and solar (WWS) power. They find that it would be plausible to produce all new energy from WWS in 2030, and replace all pre-existing energy with WWS by 2050.
In Part I of their study, J&D examine the technologies, energy resources, infrastructure, and materials necessary to provide all energy from WWS sources. In Part II of the study, J&D examine the variability of WWS energy, and the costs of their proposal. J&D project that when accounting for the costs associated with air pollution and climate change, all the WWS technologies they consider will be cheaper than conventional energy sources (including coal) by 2020 or 2030, and in fact onshore wind is already cheaper.
Summary
To sum up, there are several types of renewable energy which can provide baseload power. It will be over a decade before we can produce sufficient intermittent renewable energy to require high levels of storage, and there are several promising energy storage technologies. One study found that the UK power grid could accommodate approximately 10-20% of energy from intermittent renewable sources without a "significant issue" (Carbon Trust and DTI 2003). By the time renewable energy sources begin to displace a significant part of hydrocarbon generation, there may even be new storage technologies coming into play. The US Department of Energy has made large-scale energy storage one if its research priorities, recently awarding $24.7 million in research grants for Grid-Scale Rampable Intermittent Dispatchable Storage. And several plans have been put forth to meet 100% of global energy needs from renewable sources by 2050.
Last updated on 4 November 2016 by dana1981. View Archives
Question....Some time ago I received comments from folks at SKS that they might post a lead article by me on CO2 offset solar charities. Months have passed and I have interacted with many such organizations plus found some interesting facts. For instance, largely due to "The Swanson Effect" (crystalline silicon solar cells are factor 35 cheaper than ~30 years ago) what used to be a charity is now likely a business, though a small one. Great news in most respects but bad news for innovators like Solyndra or concentrating solar projects such as Desertec, perhaps. Developing country inhabitants can power and light their homes cheaper with solar than using kerosene or going onto the grid. Now what should I do? I can send something written up, but to whom, and in what form, and what happens after that?
curiousd @81 - use the Contact Us page. John Cook will respond and then you can email him whatever you've written up.
ThinkProgress has an article about Portugal generating 70% of their power for the first quarter of this year from renewables. They had about 37% from hydro and 27% from wind. Solar was only 0.7%. (I am not sure why the numbers do not add up to 70%. The original Portugese press release contains these numbers). Since hydro is the most flexible method of power generation (more flexible than coal, gas or nuclear), being able to ramp up quickly if needed and available at any time, they are able to easily use a lot of wind. Apparently it was rainy and windy so they got a lot more renewable than last year. They saved a lot of cash not buying coal and gas. For those who say renewables cannot provide more than 40% of energy, what do you think about this proof of concept? They exported about 6% of energy used. Presumably they exported on windy days. Stilll nowhere near as much export as the nuclear plants in France have to do every night.
The San Onofre nuclear power plant in Los Angeles is being permanently closed. They were intending to expand generation capacity and installed a badly engineered heat exchanger. They have decided that it is too expensive to fix. Florida still has a broken plant we are paying for. The utility makes 10% on everything they spend on the plant, even if it never generates more electricity.
If it is uneconomic to repair an existing plant, how could it be economic to build a new plant?
Wind and solar keep looking better and better.
Moderators: I couldn't find a better thread for this post. If you suggest one I will repost and this one can be deleted.
Has anyone at SKS registered the fact that Dr. James Hansen has been coming out ever more strongly in recent years in support of nuclear power? To be sure, Dr. James Hansen would not agree with the content of this article. At all. According to Hansen, renewables are *not* up to the task. James Hansen is saying very clearly that nuclear power will be necessary in order to combat climate change effectively:
http://www.youtube.com/watch?v=CZExWtXAZ7M
Is SkS going to be a climate change science platform that keeps distancing itself from James Hansen? It would be nice to see a firm statement by SkS that leaves no doubt, so readers of this website know how to judge the ideology and politics of this website. Either one of the following statements will make it clear for readers what the position of SkS is. Please choose one or suggest a better statement?
Option 1: "SkS denies that Dr. James Hansen knows what he is talking about, concerning renewables and nuclear power with respect to combatting climate change. SkS confirms that Hansen is utterly mistaken and misinformed about this subject."
Option 2: "SkS agrees with Dr. James Hansen and will update it's articles to correctly reflect Dr. Hansen's informed position on renewables and nuclear power, in regard to combatting global warming."
I hope SkS will take the time to clarify it's position in regard to Dr. James Hansen's conclusions on nuclear power, renewables and combatting climate change, clearly for all readers, since this issue is crucial.
Thank you,
Joris
JvD,
Perhaps the issue is that no-one wants to volunteer the time to write a paper supporting nuclear power. You are welcome to write such a paper and submit it to SkS. I have submitted papers in the past, it is not hard. Such a paper would undoubtedly get a lot of comments. It is not the job of other SkS volunteers to support your private opinions. In general, SkS does not go deeply into solutions, that is left to other venues.
Hansen has supported nuclear for a long time. Nuclear requires another $100 billion or more to develop it into a solution for AGW, if it turns out that it can provide the necessary power. India does not seem to be getting very far with their nuclear efforts. Perhaps if we build a reactor in Syria they will have less troubles, or maybe it will melt down during the war. On the other hand, new wind is currently cheaper than coal and nuclear and is ready for deployment. Syria can use wind without risking nuclear holocast.
In my part of Florida we have the highest rates for electricity in Florida because of failed nulcear power plants. What is your response to this boots on the ground truth?
"What is your response to this boots on the ground truth?"
I take it that you deny Hansen's position. You do this by cherry-picking a single failed nuclear project, which is exactly the kind of wrong approach Hansen talks about in the video. Hansen says that we shouldn't discard nuclear power because of single instances of failure (such as Fukushima), in the same way that we don't discard air travel due to a single airplane crash.
Did you even watch the video? It's not long.
Anyway, my response is irrelevant. My question concerns whether SkS accepts or denies Dr. James Hansen's position on nuclear power, renewables and combatting climate change. I've already discussed this issue with you in the past, and you are the kind of environmentalist that James Hansen is particularly concerned about. If you don't mind, I'll your claims for what they are.
[JMH] You are skating on the thin ice of excessive repetition and sloganeering -- both of which are prohibited by the SkS Comment Policy. Please cease and desist or face the consequences.
JvD,
I see that you are unwilling to write up an article to support your position. Come back when you are ready to do the hard work. Instead you criticize others for not doing your work for you. You would be better off on a site that discusses solutions to AGW (that you have been referred to before) rather than criticizing SkS for not doing something that is not their purpose.
It is impossible for me to "deny" Hansens position since it is only his opinion and not a consensus position of scientists. You are being deliberately provocative which is against the comments policy. Frankly, Hansen is an extreme position on this issue. The tide of opinion is going against Nuclear. I was pro nuclear 5 years ago before the recent, multiple disasters.
It is a waste of SkS space to discuss nuclear further, you have provided no new data to support your position. Nuclear is not allowed on Real Climate because of people like you.
JvD - You seem to be presenting a False Dichotomy in your post. Technically, as discussed in the opening post, renewables are capable of baseload power, and are likely to be economical for that in many regions, with Budischak et al 2013 ("Cost-minimized combinations of wind power, solar power and electrochemical storage, powering the grid up to 99.9% of the time") a good example of actually running the numbers. On the other hand, there will be regions such as the UK where land area and energy density limits might make nuclear more economical, a decision dependent on a region by region basis.
You are demanding an either/or approach, and that (IMO) is an inaccurate representation of the topic. Mitigation and adaptation to climate change are going to require flexibility.
I think you are minunderstanding Budischak's paper. Budischak concludes that it would not be economical at all!
Budischak monetized and included the external cost of energy in order to arrive at the conclusion that a high-penetration renewables energy system would not be more expensive that today's energy including externalities. He uses a figure of about 10 ct/kWh for the cost of these externalities in today's mix. In other words: Budischak's conclusion is that a renewables electricity system would cost about 10 ct/kWh more than a nuclear-based electricity system, since the external cost of nuclear energy is negligable (which Budischak confirms). Budischak even includes expected future cost reductions of renewable energy systems, which means that using today's technology would be even more expensive.
The correct conclusion to be drawn from Budischak is that nuclear is far more economical than renewables, because it does not have the negative externalities that fossil fuels have, nor does it have the high internal costs of renewables. That is why James Hansen is adamant that nuclear power will be crucial in trying to solve the climate change problem. If we don't use nuclear, then society will be locked into fossil fuels, because we can monitize externalities in our desk studies 'till hell freezes over, but societies are extremely unlikely to monitize them, except in the richest regions where these externalities are likely to draw the needed political support for increasing the cost of energy by 10 ct/kWh.
To decarbonise the entire system, it is nuclear or bust, because nuclear is cheap and clean, while renewables are merely clean! Budischak's study results confirms this, if anything.
Now to get back to my original question, which has not been answered. Does SkS agree with James Hansen or not (see the above short video I linked which lays out James' position)? You either agree, or you don't agree, IMHO. I take it you don't agree with Hansen?
@Michael,
There is ample literature that supports my view. For example:
http://www.350.me.uk/TR/Hansen/BarryBrook.pdf
Meanwhile, I notice that you have now stated that - according to you - James Hansen's opinion on renewables, nuclear power, and solving the climate crisis are wrong.
It would be nice if you did your homework can proved that Hansen it wrong. Or do you suggest that I trust your private opinions on the subject at face value, rather than James Hansens!? ;)
JvD,
SkS does not have a position on nuclear. SkS exists to document and counter misconceptions about human caused global warming. SkS takes the consensus position on issues where a consensus exists. Hansen's position is an outlier, not a consensus position, and is not directly related to SkS goal of countering false information about global warming. For those reasons SkS does not take a position on Hansens issue. Without asking, I am sure that the people who post on SkS have a variety of opinions about your pet peeve, some support you and some do not. You are not convincing anyone to support your position by constantly nagging others to do your work for you. For example, I am agnostic about nuclear but you have labeled me as an extreme enviro against all nuclear. Why are you so incorrect in your assessment of me? It is due to your posting style which alienates even those who might support you.
As has been pointed out to you many times before, SkS is run by volunteers who write the posts. You are welcome to do the work and write a detailed post about nuclear supported by peer reviewed science, Industry brag sheets are not generally considered peer reviewed, nor are online videos. These types of posts come on SkS occasionally, like the one we are currently posting on, so it is likely to be posted. Since you are unwilling to do the work to support your position you should stop complaining about others not doing your work for you. By constantly repeating yourself you are sloganeering which is against the comments policy.
Moderator: if my comments about SkS policy are incorrect please delete this post, since I do not represent SkS.
Lastly, and that will be it for me unless I'm challenged to explain myself again. I realise that the nuclear energy issue is being prohibited from discussions about solving the climate crisis on certain discussion boards. I consider SkS better than that. Interestingly, James Hansen actually has an important thing to say about why actual solution to climate change (such as nuclear power) are often disparaged and ignored, here:
http://www.columbia.edu/~jeh1/mailings/2011/20110729_BabyLauren.pdf
@Michael,
"Industry brag sheets?"
I posted a peer-reviewed scientific article written up by the respectable Barry Brooks!
And the video of Hansen I posted is relevant, because it directly contradicts the contents of the above article (and other articles on SkS) which is supposed to be part of the 'myth busting' series of SkS. You clearly don't like that, which is why you have now stated that James Hansen is wrong about renewables, nuclear and solving climate change, but you do not support your opinion. On the contrary, you turn around on and accuse me of not supporting my opinion! Even while I have presented clear arguments and provided literature supporting my views.
JvD @90, SkS does not "agree" with anything. That is because SkS is a website, not a person. The website is run by a number of volunteers who agree and disagree about many different things. As you have already been invited to do, you are quite welcome to write a post making the case for a nuclear future to mitigate climate change. Such a post will undergo the normal SkS "peer review" process, ie, any volunteers who are interested will look at the post, make comments about how it can be improved, and/or recommend it to be published, or not published. Should it be published, it will not be the SkS view, but the opinion of JvD published on SkS (just as my posts on SkS are not the "SkS view", but just my opinions published on SkS). However, if you are not prepared to put that effort in, you have no right to complain about the absence of such a post. You will also have no right to complain if your repetitive brow beating is ruled off topic under other posts (as it mostly is - not to mention tedious).
FYI, I have virtually no opinion on nuclear energy. I am quite happy to have nuclear power as one of the options, but will not impede the already difficult political fight to do something effective about global warming by tying it to a nuclear agenda. Beyond that, I am quite happy to just put a price on carbon and let the people actually building the power plants decide which will generate most efficiently and hence give them the greater profit.
Further to JvD @90:
Tell that to the people of Okuma, Fukushima.
I do have one more relevant opinion about nulear power. That is that the announcements of overwhelming safety by people who favour nuclear power are simply not to be trusted. Do not misundertand me. The catastrophe at Fukushima is small scale compared to the prospect of global warming. If the price of stopping global warming is a Fukushima a decade, and we cannot do it any other way, that is a price we ought to pay. But the people who tell us the nuclear power is risk free, and (even more unbelievably) external cost free are the same people who were making jokes immediately after Fukushima about how the radiation release was less than the dose from eating a banana a year - until the real figures started leaking out.
They were so confident about the safety of nuclear power that they did not recognize a genuine, and major emergency when it occurred.
And yet they expect us to accept their blandishments about the safety of nuclear power as gospel.
So when JvD asserts that "the external cost of nuclear energy is negligable" all that tells me is that his opinion on the safety of nuclear power is not to be trusted.
[DB] All parties should confine comments about nuclear power to the pertinent and relevant areas of supplying baseload power. The negatives of nuclear power, a la Fukushima, while pertinent in the real world and relevant in terms of being inclusive negative externalities of nuclear power, do not fall under the aegis of this thread and are thus off-topic from this point forward.
This thread is about the ability of renewables to supply baseload power. As such, discussions of nuclear power in a direct capacity are off-topic on this thread as well.
"As you have already been invited to do, you are quite welcome to write a post making the case for a nuclear future to mitigate climate change."
It's already been done. I posted the article by Barry Brooks. There is nothing I could or would want to add to it.
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[DB] Sloganeering and moderation complaints snipped.
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[DB] Off-topic snipped.
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[DB] Off-topic snipped.
JvD,
a few points from someone who is broadly speaking, a supporter of nuclear.
1) Your tone is aggressive, and counterproductive.
2) (-snip-).
3) (-snip-).
4) (-snip-).
5) (-snip-).
Tom Curtis's suggestion that you submit a post is excellent.
[DB] Off-topic snipped.