Study projects thermoelectric power in Europe and US vulnerable to climate change due to lower summer river flows and higher river water temperatures
03 June 2012
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| Projected changes in summer mean usable capacity of power plants in the US and Europe for the SRES A2 emissions scenario for the 2040s (2031–2060) relative to the control period (1971–2000). Source: van Vliet et al. Click to enlarge. |
A study published in Nature Climate Change suggests that thermoelectric power plants (i.e., nuclear and fossil-fueled generating units) in Europe and the United States are vulnerable to climate change due to the combined impacts of lower summer river flows and higher river water temperatures.
In the US and Europe, at present 91% and 78% of the total electricity is produced by thermoelectric power plants, which directly depend on the availability and temperature of water resources for cooling. An international team of researchers projected a summer average decrease in capacity of power plants of 6.3—19% in Europe and 4.4—16% in the United States depending on cooling system type and climate scenario for 2031—2060. In addition, probabilities of extreme (>90%) reductions in thermoelectric power production will on average increase by a factor of three.
Compared to other water use sectors (e.g. industry, agriculture, domestic use), the thermoelectric power sector is one of the largest water users in the US (at 40%) and in Europe (43% of total surface water withdrawals). While much of this water is recycled, the power plants rely on consistent volumes of water, at a particular temperature, to prevent overheating of power plants. Reduced water availability and higher water temperatures—caused by increasing ambient air temperatures—are therefore significant issues for electricity supply.
Higher water temperatures and reduced river flows in Europe and the United States in recent years have resulted in reduced production—or temporary shutdown—of several thermoelectric power plants.
The research was undertaken by an international team of scientists from the Earth System Science and Climate Change Group, Wageningen University and Research Centre; The Netherlands, The Department of Civil and Environmental Engineering, University of Washington, Seattle, USA; Forschungszentrum Jülich, Institute of Energy and Climate Research–System Analyses and Technology Evaluation, Jülich, Germany; and the International Institute for Applied Systems Analysis, Laxenburg, Austria.
Using a physically based hydrological and water temperature modeling framework, the team produced a multi-model ensemble of daily river flow and water temperature projections for Europe and the US over the 21st century. It then produced daily simulations of river flow and water temperature for the periods 1971–2000 (control), 2031–2060 (2040s) and 2071–2100 (2080s) by forcing the coupled hydrological–water temperature model with bias-corrected global climate model (GCM) outputs for both the Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) A2 and B1 global emissions scenarios.
The A2 scenario considers a world of fragmented and slow technological change, whereas the B1 scenario assumes environmental sustainability and a much more rapid introduction of renewables. Both SRES A2 and B1 were selected, because they represent contrasting storylines and indicate the largest range from the four IPCC SRES main emissions scenarios.
To quantify climate change impacts on usable capacity of existing thermoelectric power plants, the researchers used the resulting daily water temperature and river flow projections in combination with power-plant-specific data of cooling system, efficiency and environmental restrictions for 61 power plants in the US and 35 in Europe, including both nuclear and coal-fired power plants with different cooling systems.
Among their findings were:
For 76% of the power plants with once-through or combination cooling systems and 41% of the power plants with recirculation systems, electricity production potential will be reduced significantly as a result of the projected increases in daily water temperature and decreases in summer flows for the 2040s.
The summer average usable capacity of power plants with once-through or combination cooling systems is projected to decrease by 12–16% (US) and 13–19% (Europe) for the 2040s (for B1–A2 SRES emissions scenario).
The occurrence of periods with large reductions in usable capacity will increase in the 2040s.
For recirculation (tower) cooling systems, the decrease in usable capacity during summer is much lower, but non-negligible (on average 6.3–8.0% for power plants in Europe and 4.4–5.9% in the US).
An additional problem for the plants using once-through cooling is that by design, water pumped water from rivers, lakes, or the sea to cool the turbine condensers is then returned to its source, often at temperatures significantly higher than when the water entered the plant. This causes downstream thermal pollution affecting, for example, life cycles of aquatic organisms. Both the US and Europe have strict environmental standards with regard to the volume of water withdrawn and the temperature of the water discharged from power plants. Thus warm periods coupled with low river flows can lead to conflicts between environmental objectives and energy production.
Owing to the smaller adaptive capacity of the thermoelectric sector for the SRES A2 scenario, the vulnerability to climate change will be substantially higher for the SRES A2 when compared with the B1 scenario. Although replacement of once-through by recirculation systems reduces freshwater withdrawal, water consumption increases (owing to evaporative losses) and could therefore contribute to higher water scarcity. Dry cooling systems or non-freshwater sources for cooling are possible alternatives but may be limited by locally available resources and have costs and performance disadvantages.
A switch to new gas-fired power plants with higher efficiencies (∼58%) could also reduce the vulnerability because of smaller water demands when compared with coal- and nuclear-fueled stations (with mean efficiencies of ∼46% and ∼34%). Considering the projected decreases in cooling-water availability during summer in combination with the long design life of power plant infrastructure, adaptation options should be included in today’s planning and strategies to meet the growing electricity demand in the twenty-first century. In this respect, the electricity sector is on the receiving (impacts) as well as producing (emissions) side of the climate change equation.
—van Vliet
The study was supported by the European Commission’s FP6 WATCH project and through the FP7 ECLISE project.
Resources
Michelle T. H. van Vliet, John R. Yearsley, Fulco Ludwig, Stefan Vögele, Dennis P. Lettenmaier and Pavel Kabat (2012) Vulnerability of US and European electricity supply to climate change. Nature Climate Change doi: 10.1038/NCLIMATE1546
Switching to NG + more efficient cooling towers could counter act the effects of warmer weather on power plant efficiency.
Posted by: HarveyD | 03 June 2012 at 11:16 AM
And of course the most obvious one: PV, with 0 water requirements.
Ah, never mind. 20th century thinking is so ingrained in some people.
Posted by: Arne | 03 June 2012 at 12:23 PM
Another 'no, really' moment from climate 'scientists' [/end sarcasm].
Most power plants have a summer and winter capacity rating because they are less efficient in hot weather. It gets worse. Low river flow during a drought means less hydroelectric power. Hot summer weather means more demand for power when it is critically needed. The same conditions that cause extreme hot weather generally mean no wind either.
What does this leave? Inefficient SSGT which are made efficient CCGT by using cooling water to condense steam. There you have it, the solution becomes part of the problem.
The interesting thing is that there are only a few deaths during hot weather in places like Spain or Arizona. People drop like files in places with normally cool summer weather and too many liberal politician when the weather gets got. It is better to have a power plant and not need it, then need a power plant and not have it.
Utilities are very good at long term planning, Restriction on plant operation because of hot weather are very short lasting only a week every five years. Having a bunch of SSGT sitting around does not cost all that much.
Posted by: Kit P | 03 June 2012 at 12:47 PM
Germany could use the money earmarked to bail-out Southern Europe to construct large-scale solar therma--electric power plants in the sunny Mediterranean countries. That will really boost the economies there without any risks of default on future loans. Then, construct HVDC lines to link those solar electricity sources to Northern Europe. Solar thermal stations can have thermal storage for night-time electricity without interruption.
Excess solar electricity in the summers, springs and winters can be used to make H2 to be stored locally in Northern Europe for winter use and for FCV's and other H2-vehicles. This can allow Europe to be energy independent without the energy stranglehold from the Russian NG pipeline and from Middle East oil, AND solve the economic crisis at the same time. Two payback fer one investment ain't too bad a deal!
It may cost more for renewable energy at the moment, but the cost will come way down with mass production and mass installation, just like HDTV's and all other electrical appliances. Since more people will be employed with massive renewable energy developments, the governments will spend a lot less on social services such as unemployment benefits, the overall cost to society may be the same, since Europe is highly socialistic.
With sufficient renewable energy coming on line from Southern Europe, Germany can really shut down all their nuclear stations by 2020 as planned! Fossil-fueled power plants will be...ah...like fossils...
@Kit P,
Use more inefficient SSGT and be held hostage again to Russia's NG like some years ago? Never mind global warming...I don't even have to use global warming nor climate change as additional motivations for the rapid switch to renewable energy.
Posted by: Roger Pham | 03 June 2012 at 04:56 PM
Since a huge amount of the summer-peak power demand is for A/C, solar-powered A/C would address the problem too. Even solar-powered dehumidification; warm air is tolerable so long as it's dry.
Posted by: Engineer-Poet | 03 June 2012 at 08:49 PM
Funny that they don't mention hydroelectricity, as that is the one that is hit by far the worse by drought, which also puts a stopper on 'cunning plans' to store renewables as hydropower in Norway.
They say:
'Compared to other water use sectors (e.g. industry, agriculture, domestic use), the thermoelectric power sector is one of the largest water users in the US (at 40%) and in Europe (43% of total surface water withdrawals). While much of this water is recycled'
Make that: 'almost all'
The net withdrawals are absolutely tiny ocmpared to those for agriculture and industry.
This all smells of an agenda to me, although care must be taken of course to manage water resources.
No doubt the authors will be pleased to learn that it is perfectly practicable for nuclear at least to greatly reduce water use, by recycling, semi-dry cooling and so on, at a small hit in energy efficiency.
It's weird that these eco-warriors never draw our attention to, for instance, the impact which a major volcanic eruption would have on solar output.
Any society depending heavily on it would be in deep trouble.
Posted by: Davemart | 04 June 2012 at 12:57 AM
Is there any form of power generation that is more expensive than solar thermal?.. lots and lots of moving parts is good for keeping an army of workers employed in sunny Spain.
Posted by: Herm | 04 June 2012 at 12:58 AM
Yeah, pv is a lot more expensive than solar thermal.
Wind is also highly dependent on hydroelectric resouces as well as thermal plants to shift load.
Of course, a hot, dry period is usually associated with calms, so there would likely be little load to balance.
They could always fire up their coal and gas plants to 'load balance' ie provide 75% of their power as they always do.
Oh, hang on........
Posted by: Davemart | 04 June 2012 at 01:18 AM
Dry summers are not really an issue. They limit the amount that can be generated over a period of time, but much less the available bandwidth for balancing capacity. When little rain falls, this does not mean that suddenly all the lakes fall dry. They just fill up more slowly. But they will empty more slowly too, since the sunny weather provides us with ample production of solar power. And plans are emerging to convert dams in Norway to pumping operation, thereby almost reducing water requirements to 0. Nice try though.
Provably untrue. PV installation costs hover around 2 euros per W in Europe, while solar thermal is around 5 per W. In the US a large solar thermal project was recently canceled and replaced by PV, because the latter was cheaper. Since August 2011, PV has gotten a lot cheaper still and will continue to drop in price. The near future looks bleak for solar thermal. Longer term though, the added storage may enable solar thermal technologies to compete, since it can produce power on demand, which is to say, when the spot price is high.
PV has reached and undercut grid parity in many European countries for consumers.
Posted by: Arne | 04 June 2012 at 06:03 AM
@Roger:
'Germany could use the money earmarked to bail-out Southern Europe to construct large-scale solar therma--electric power plants in the sunny Mediterranean countries.'
They use cooling water just like coal and nuclear plants.
The difference it that by their nature they have to be put in dry, sunny, water-stressed places.
Posted by: Davemart | 04 June 2012 at 06:57 AM
@Anne:
'PV installation costs hover around 2 euros per W in Europe'
Bargain. That is $2.23W if your figures are correct since you do not source them.
For Rotterdam in December you get an average of 2% of nominal capacity in December, unless you fancy doing without power in the winter. or an average throughout the year of around 12.5%:
http://www.gaisma.com/en/location/rotterdam.html
That comes to about $17.8W for the basic power, ignoring the inconvenience of not having power in winter, and forgetting all about the huge back up costs etc.
You also seem to be under the weird impression that rainfall will not affect Norway's ability to pump out electricity from hydro.
Perhaps this will disabuse you:
'The map shows interesting patterns and issues drought potential on a European scale. For example, Norway has problems with water deficiency because the country's economy is strongly depending on hydropower. Even though Norway has some of the rainiest places in Europe small negative deviations in precipitation can lead to energy problems because the water reservoirs are not refilled appropriately'
http://www.preventionweb.net/english/professional/maps/v.php?id=3824
Since we are saying that drought will decrease the ability to use coal and gas, and wind has a horrible time in dry, still weather, it is difficult to know where the power is to come from in a renewables heavy society.
It is perfectly possible to design nuclear plants with far lower water draw, you will be pleased to learn, at comparatively small extra cost.
it is also interesting that the effects of a major volcanic eruption obsuring the sun never seem to be held against solar.
Posted by: Davemart | 04 June 2012 at 07:20 AM
@Anne:
So you ahve a hot, dry summer, during which you have scads of solar.
That depletes the ability to pump out fossil fuel power, and depletes reservoirs.
So what do you do around January in Holland, with solar miniscule, even in comparatively cloud free conditions?
Little spare capacity from Norway, and wind and solar both derisory, with fossil fuels unable to pick up the slack, as they so often and so greatly have to do with the various 'cunning plans' for renewables everywhere?
So far what they have managed to do is destabilise the grid in Germany, to the extent that there is some danger of bringing it down, taking much of the European grid with it.
Posted by: Davemart | 04 June 2012 at 07:30 AM
The reason we have been making power with steam for a 100 years is because it works very well. Periodically people who do not produce power think renewable energy will save mankind. With a few limited exceptions renewable energy does not work very well. We are in the process of demonstrating by building lots of solar and wind that it does not work very well. It is okay to have some of our power come from sources that do not work poorly.
I think I we should build as much renewable energy as we can if for not other reason that to show you can not replace steam plants. In any case it is not a problem, rarely to steam plants have to reduce power because of cooling water.
I just got done reviewing a cooling water system for nuke plant on a river. The plant was designed for river water up to 85ºF but it has gotten up to 92ºF a few times. They did an evaluation at 95ºF. Only one system has a problem. Chillers for the control room are limiting but could be redesigned if it was a more frequent issue.
To put it in perspective, we know how to cool power plants and can adapt to changing conditions. A power plant that supplies a large city uses very little water compared to a large city and very tiny compared to agriculture.
Posted by: Kit P | 04 June 2012 at 07:55 AM
Water supply (rainfalls) seem to be increasing with climate changes in Northern Canada. Will it also be the case in Northern Europe and Asia?
Will this trend keep up?
Pretty soon, waters in Alberta will be so polluted with tar sands residues and deformed fishes that hydro may be the only use left.
Posted by: HarveyD | 04 June 2012 at 09:09 AM
http://www.solarnrg.nl/prijzen-zonnepanelen/prijzen-zonnepanelen-senersun-ssp60c240/prijzen-zonnepanelen-senersun-ssp60c240-plat-dak
Take the 2400 W set, with a Steca A 2010 DC M inverter for 3900 euros. Add a thousand euro installation cost (see here), and the total comes to 4900 including VAT. This is a well-known installer with a good reputation.
Please Davemart, we've gone over this before, don't repeat this over and over again. No one plans to rely 100% on solar. Can you remember that: no 100% solar, so your question is irrelevant. There are other sources that produce more in winter like wind. There are on-demand sources like biomass. This game of evaluating each source in isolation is rather tiresome.
This is also the endless repetition of the same old lame argument. That persistent calm windless weather is always localised, never across all of Europe. As you should remember, part of the plan is a strong grid in Europe, which has already started with HVDC lines across the North Sea: NorNed, BritNed. More lines (NorGer, Northlink) are proposed or in planning.
We can easily stock up on biomass for a long time for any freak events of unexpected calmness.
The long term future I see for PV is its ubiqitous installation in buildings at a negligible incremental cost. It's almost free energy that nobody cares about if you only use 50% of it (if you think that's weird, think again. Everyone thinks its normal that an average car does not use 80% of the energy in petrol).
You forgot that pumped hydro does not deplete reservoirs. And absolute absence of any rain or wind is something that will simply not happen. What-if-scenarios do not have much value if the chances of it happening in the real world are 0.
You'd be surprised what a sunny day in January yields. It's about 40-50% of a sunny day in the summer. Buy a small PV set and see for yourself. It's really enlightening to learn what you're talking about. It is pretty nifty technology.
Now I'd like to ask you for a source.
I never did say nothing negative over fossil or nuclear power's inability to run at full power in warm summers. Are you attacking a ghost? ;)
Posted by: Arne | 04 June 2012 at 11:14 AM
Combo (Hydro + Wind + Solar) is ideal when you make Wind/Solar the primary power sources, to use 100% of their installed production and use variable production hydro (with its huge water reservoirs as ideal storage) for peak loads and to replace Wind/Solar during their low production periods.
The ideal installations would have Hydro facilities over equipped by 100% to 200% to better cover higher peak loads, specially when wind/solar are not producing or are at low production periods. Whenever water reservoirs are over drained it would be the right time to install more Wind/Solar production facilities.
The ideal would be to keep the water reservoirs 90% to 100% full to maximize the water turbines efficiency and power production.
We have an ideal location with 95,000 megawatt Hydro potential (about 48,000 or 50% is already harnessed) and about the same Wind potential (only about 5% is currently harnessed). Solar potential is not as good up North but not that bad along the USA border.
Those three clean energy sources can produce enough energy for the next 100++ years and for at least 5 electrified vehicles per household.
Posted by: HarveyD | 04 June 2012 at 12:43 PM
When you're discussion 100% renewables in the future you're really talking 20+ years into the future. Probable technologies should be included, don't you think?
Tidal is developing well. Water is so dense and the tides spread out time-wise that we're likely to install tidal turbines where possible.
Wave, the technology is not that far along, but should be viewed as at least "possible".
Run of the river hydro is likely to increase.
Geothermal is almost certainly going to increase. Enhanced/hot rock geothermal seems only a good drilling technique away. That's a lot of "rumbling along 24/365" supply.
It's likely that we'll capture methane from municipal sewage systems and waste streams. Great for fill in power using already paid for NG plants.
Large scale battery technology seems to be right on the edge of breaking into the mix. It's already being used in wind farms and starting to appear on the general grid. If we get battery storage below $0.03/kWh then it becomes less likely we'll build a lot of pump-up hydro.
The larger the mix, the wider the grid, the easier it will be to make things work smoothly. And it's not that we need to get our CO2 emissions down to zero. Just down to an acceptable level. There will still be some room for fossil fuels which would make excellent "deep backup" for those mythical days when the sun doesn't shine, the wind doesn't blow, the waves don't break, ....
Posted by: Bob Wallace | 04 June 2012 at 06:32 PM
Oh, and once we get that new grid together 20, 30 , 40 years from now we should take heart in the realization that usable fusion will be only 20 years away.
Posted by: Bob Wallace | 04 June 2012 at 07:22 PM
Bob - you've got to keep up with where fusion is going. Thing is, you can't look at dinosaur hot fusion we've spent $250 billion on (delivering ZERO net energy) - there is far more efficient fusion under development:
https://www.youtube.com/watch?v=42hrCRx1JJY
Posted by: Reel$$ | 04 June 2012 at 09:22 PM
@Davemart,
Solar thermal can also run on super-critical CO2 Recompression Brayton cycle (s-CO2) at even higher efficiency than a steam Rankine cycle, without requiring any cooling water. Nuclear plant can also run on s-CO2 cycle without requiring any cooling water. Coal-fired power plants do not run as efficiently on s-CO2 cycle as on steam Rankine cycle, ergo the need for cooling tower.
The price of PV panels will get cheaper, to the point that every roof top will have them, and excess output will be used to generate H2 to be stored for later use or for transportation.
Posted by: Roger Pham | 04 June 2012 at 10:55 PM
sCO2 requires rather cool low-side temperatures to get the compressor input conditions right. Doing this without cooling water (and reasonably cold water at that) seems unlikely; cooling to the ~38°C critical temperature when the outdoor air temp is close to or even above this is Not Going To Happen.
Posted by: Engineer-Poet | 04 June 2012 at 11:10 PM
Good point, E-P. You really have good grasp of thermodynamic. I was just oversimplifying the issue for the general participants without bogging down on the details.
What I really meant was to use solar PV panels for daytime electricity needs, and store thermal energy as heated molten salt in large tanks for night electricity production. Certainly cooling to 38 C can reasonably be achieved for most of the NIGHT without the use of evaporative cooling tower, since dry, cloudless areas really do cool off quickly after sundown. Large volume of water can be cooled at night and near dawn via air to water heat exchanger (radiator) for use in non-evaporative cooling purpose in the late afternoon hours when the solar PV output is declining and yet the air is still warm.
Again, thanks for the important input.
Posted by: Roger Pham | 04 June 2012 at 11:28 PM
there is far more efficient fusion under development:
https://www.youtube.com/watch?v=42hrCRx1JJY
Yeah but just don't count on seeing that form of fusion anytime soon. Even Zawodny keeps using terms like "maybe" and "if." He and others at NASA are thinking about what might be possible decades from now. We need solutions NOW.
Posted by: ai_vin | 05 June 2012 at 02:10 AM
What about Algae?
Posted by: Lucas | 05 June 2012 at 07:47 AM
Bob...100% renewable energy is already a very strong possibility depending where you live. In the last 10 years we have closed our 4 coal fired power plants and will probably close our sole nuclear plan within 12 to 24 months. Will remain about 48,000 megawatts of installed Hydro and 3,000 megawatts of installed wind turbines in operation. Those two renewable energy sources supply an average of about 28,000 megawatts with winter time peaks approaching 40,000 megawatts. Without the energy saving programs, those peaks would be over 45,000 megawatts. Eventually, both Hydro and Wind can be developed to 95,000 megawatts each.
With improved interconnections and grid management, pump-up hydro will not be required. It is just a matter of using Wind power as primary e-energy source and using (variable) Hydro to supply the rest. To be able to handle higher peaks, Hydro facilities (turbines) must be added (i.e. over equipped). With 30 to 40 hydro facilities (and reservoirs) over a very wide area, water management is important but possible.
Posted by: HarveyD | 05 June 2012 at 08:23 AM