The threat of sea level rise to the nuclear industry

In this week's post I will be taking an alternative view on the relationship between nuclear power and the environment, considering how the environment threat of sea level rise (SLR) could hinder the safe operation and development of future plants.

Nuclear power plants are built close to the coast to reduce the costs of transporting vast quantities of water needed for cooling inland Source: Guardian, 2012

At present few nuclear power stations are waterproofed and many in the US and Japan in particular have no sea wall (Lipscy, 2012). Substantial sea level rise could put more locations at danger and heighten the need for protection. 

Likely SLR? 
The extent of SLR is key in quantifying the risk to the nuclear industry. The recently published fifth IPCC report projects a rise of between 0.33 -0.63m by 2100  for the middle emission scenario. However this projection is far from precise and not universally accepted; some semi-empirical models have predicted SLR up to twice as high by the end of the century (IPCC, 2013). 

Confidence in the IPCC projections have been reduced by the fact that model estimates  of the various contributions to the budget (upper four blue entries) have been consistently below the observed rates, However as can be seen in the error bars there is uncertainty in both measures and some palaeodata (see Siddall et al, 2009) has supported the modesty of the IPCC projections Source: IPCC, 2007

Calculating the future sea level budget is by no means easy, it requires accurate estimates of  thermal expansion and related ocean heat-content change, by far the largest store in the climate system (Church et al, 2011). However perhaps the biggest tripping point is in the likely contribution of the Greenland and Antarctic ice sheets over the next century. This is something which the IPCC has played down, however there is a growing body of evidence to suggest that rapid dynamical changes are happening. Take Church (et al, 2011) study, introducing a terrestrial storage term and using higher estimates of sea-ice contribution it was able to accurately close the sea level budget for the period 1972-2010, unlike the IPCC. Significantly, using an energy balance model, it found that since 2004 the ice sheets contributed to sea level at a combined rate of 1.3mm yr^-1, a level approaching the combined rate of upper ocean thermal expansion and glacial ice, not represented in IPCC models. Many believe that the Greenland and Antarctic ice sheets are an important component in closing the sea-level budget, particularly since 1993, and could as a result lead to additional sea level rise into the 21st century. 

IPCC projections of global mean sea level rise over the 21st century across all representative emission pathways Source: IPCC, 2013

How big a threat? 

Given the lack of constraints on future SLR there is uncertainty with any risk assessment. At present, according to a study by Lipscy (et al, 2012) nuclear power in most areas appear safe (see below). However if greater than expected SLR is realised in combination with an increase in storm surge magnitude and an investment in plant construction worldwide, the graph below could change significantly. 

Difference between average wave height of largest recorded event and maximum plant/sea wall height in metres. A number above zero means the plant and sea wall both lie below the average wave height of an historical incident implying inadequate protection, as can be seen most plants at present have large negative values associated with them Source: Lipscy et al, 2012

In America many have voiced concern about the safety of their current generation of nuclear power plants especially in light of Hurricane Sandy which caused the emergency shutdown of three of it's nuclear power plants. 

"We learned that they (the region’s nuclear power plants) just barely made it through safely during Sandy, but that does not imply that future storms, when combined with continued sea level rise, could not cause serious problems,” said Klaus Jacob, seismologist at Columbia University, source: Magill, 2013

Barely is perhaps an exaggeration, in truth 24 plants out of the 34 in the storms path continued to operate at 100%, but the east coast power plants are at particular risk. Climate change will not lead to uniform sea level rise everywhere, spatial variations exist in terms of circulation and thermal expansion. Significantly a recent study by Sallenger (et al, 2012) found rates  3-4 times higher than the global average along a 1000km long hotspot on the North American Atlantic coast. 

The video below summarises some of the factors contributing to the additional sea level rise along the east coast. 

What should be done? 

In response to Fukushima and in the face of the uncertainties associated with global as well as regional SLR many have touted a move away from purely probabilistic thinking when considering adequate sea wall height and plant height. There are many problems in the estimation of very low probability events, with growing non-stationarity of the climate to consider,  and the need to extrapolate the magnitude of  long return period events from a short instrumental record (NRC,2013). The risk is not solely dependent on spatial location of course, Lipscy (et al, 2012) found that more vulnerable plants were associated with the operations of larger utilities. They tend to have more diverse operations and thus pay less attention to the safety of specific plants, especially older plants nearing decommission.  

Ultimately I believe the industry needs to consider a ‘worst case’ scenario based on upper estimates of SLR rise for a particular plant's expected operating time. Government regulation is needed to ensure synchronous review of climate projections with planned plant construction. As a result there will likely be a greater need for more than adequate protection, all of which will add to cost and serves to make nuclear power a less attractive preposition. 

My next blog will look at a connection between nuclear power and climate change rarely touched upon by mainstream media, the threat of rising sea level to coastal nuclear power plants. Here's Ron Wyden, US Senator for Oregon, raisesing his concerns about the vulnerability of nuclear power plants in the US and around the World, more to follow...

Paper Review

This week I have decided to review a highly relevant paper by William Sailor written in Science in 2007. The article takes a similar premise to this blog and is simply titled “ Nuclear Energy- A solution to Climate Change?”

The premise

The paper evaluates the possibility of a global increase in nuclear energy by 2050. Sailor (et al, 2007) puts forward the scenario that carbon emissions do not exceed their current level, despite an expected doubling in world energy demand in 2050 (the paper assumes a global demand of 900EJ, fairly well matched to recent mid-estimates by the EIA and world energy outlook). This is achieved by a global energy mix of 1/3 conventional fossil fuels, 1/3 renewable/decarbonized sources and 1/3 nuclear. The paper does not assess whether the whole energy mix is possible, rather whether Nuclear energy could hold its side of the bargain.  

The World energy outlook project that growth in world energy use largely comes from poorer countries outside of the Organisation for Economic Cooperation and Development (OECD). Energy use patterns for countries inside the OECD are relatively stable between 2010 and 2040 Source: IEA,2013

A case of bad timing?

From the onset Sailor (et al, 2007) argue that with popular support nuclear could supply 1/3 of global energy (300EJ) demand by 2050, citing that world per capita nuclear output would only need to be half the current rate in France, and that the obstacles facing nuclear energy pale in comparison to those facing renewable energy. 

Sailor (et al, 2007) argue that to obtain 300EJ  from renewables would require an expansion in biofuels taking up  vast land areas needed for increasing food production. They also highlight the uncertainties in carbon sequestion along with the high costs of wind and solar energy  Source: inhabitat.com

I believe this optimism is partly due to the publication date. Pre-Fukushima, whilst ambitious, this figure was far more probable. However since 3/11, the industry has faced a major downturn (see link). Support for atomic energy has stagnated and approximations of future generating capacity have been slashed; the IEA for one halved its estimate of the additional nuclear generating capacity to be built by 2035.  That said, development of nuclear power in China amongst others could still lead to an increased share in global energy.  

Putting to one side the speculative increase in generating capacity, what do the authors, independent of popular support, consider the main obstacles facing a large expansion in nuclear power?

Paying over the odds

The paper prioritises the relative cost of nuclear power, conceding that at present no carbon free energy can compete with the combined cycle gas power plants in the USA. Sailor (et al, 2007) propose the gradual introduction of a carbon tax eventually rising to a rate of $100 per ton. A figure, which they believe, will be needed to level out the cost disadvantage for nuclear energy. To put this in context, there is no nationwide carbon tax in the US at present, and Australia, which has one of the highest rates globally, charges less than a quarter of this $100 benchmark. The article does not make clear whether the $100 is a global average or just the competitive rate required in the USA.

There is much debate on the merits of carbon taxes and the apposite rate required for climate change mitigation, which I will not go into here. Sailor (et al, 2007) are simply theorising what is needed to make nuclear power competitive and gives little idea  how a $100 rate would be introduced. However I feel the paper does neglect the recent trends in price and economical uncertainties associated with nuclear power. Sailor (et al,2007) assume that with greater research into simplified designs, along with a reduction in lead times through changes in government policy, the cost of nuclear power will stabilise. However since 2003 construction costs for all large-scale engineering projects have increased, and the cost of nuclear plants have been increasing disproportionally (Findley,2010). Nuclear plants take up to a decade to build, they need to be large and also run at full capacity to take advantage of economies of scale and be economically sustainable; in addition the projections of cost are wide-ranging. This makes them less attractive to developing countries which lack the economic flexibility of countries like the USA and France, but significantly will drive the increase in future world energy demand. 

The graph above shows the amount of CO2 displaced per dollar of investment, Nuclear is seen to give a relatively low return when compared to non-traditional alternatives such as 'clean fossil fuels' Source: Findlay,2010

The drawbacks of nuclear ambition

Another issue highlighted is that of nuclear proliferation, the paper makes the important point that no commercial plants have played a role as a bridge for national entry into the nuclear arms race, nor have subnational groups or individuals used stolen materials. However Sailor (et al ,2007) fear that the possibility of plutonium breeder reactors with greater demand for nuclear power could heighten the danger.

The paper mentions very little about how this threat could be combated politically. In truth it is very difficult to quantify, after all nuclear power could be eliminated but the threat of nuclear weapons would still remain. A nuclear reactor only gives the beginnings; the next steps are dependent on the technological expertise and the political stance of the country in question.

The authors also comment on nuclear safety and waste disposal in the context of a global increase in demand. The analysis of the former is based very much on the safety record of the current generation of reactors, and the impressive probability calculations of core damage taken from the newer crop of third generation plants. With this the paper reaches the conclusion that nuclear power is safe and only getting safer. Personally I feel the authors fail to factor in the likely problems in maintaining such low levels of risk with the introduction of nuclear power in a number of less developed countries, and thereby overestimate nuclear safety.

In terms of waste management Sailor (et al, 2007) propose its placement in deep geological depositories globally. This is the method used in almost all countries at present but I feel the paper views the issue  from a largely American-centric perspective. It focuses on the possibility of a site at Yucca Mountain, Nebraska, rather than evaluating the nature of international waste management. For example the need for international cooperation in the form of “take back schemes”, the issues of cost and capacity in certain countries, and alternatives to long term burial like reprocessing.

Final Thoughts  

Ultimately the article by Sailor (et al, 2007) is a basic critique on a hypothetical expansion in nuclear power, rather than a detailed assessment on its likelihood and extent. The paper concludes that there are no insurmountable technical barriers and that with public support and the right safeguards, nuclear energy could cater for 1/3 of demand. The figure of a 1/3 is unrealistic, and I felt the study overlooked the rising costs of nuclear power along with the likely problems encountered with its implementation in the developing world. I wouldn’t rule out a significant expansion in nuclear energy but these are two issues that need to be considered.

A worldwideweb tour of nuclear power

Just to break the blog up, this week I thought I would list a few websites  and articles which I have found helpful, and recommend to anyone looking to learn a bit more about nuclear power and the debate on future energy policy in general.

Guardian  

I found the guardian's nuclear section very useful, mainly because unlike websites like Greenpeace and Horizon Nuclear; as well as other newspapers for that matter! It does not come vehemently down on one side or the other. It has a green rather than technocratic undertone, but offers a range of perspectives on nuclear issues. The website is  updated frequently; following the situation here in the UK in detail, and reporting on significant global headlines. However its best aspect is the first thoughts section. instead of reporting issues with impartiality, news stories are critically assesed and often you get more than one perspectives from a number of writers. As a result you get a real sense of the bigger picture, in terms of arguments for , and arguments against. These are sometimes complemented with a 5-minute video debate (see link). Whilst giving only an overview, I find them a refreshing change from the one-sided articles often found in the media and in academia to a lesser extent. In the broader environment section there are also a number of blogs, which often stray onto the issues of future energy policy, I would particularly recommend Damian Carrington’s ,which is highly relevant.  

Greenpeace

Greenpeace are anti-nuclear, they have launched protests in a number of countries against nuclear power, and campaign strongly for renewable alternatives. Whilst their arguments are often one sided, they put the negatives under more scrutiny than others and prioritise the environment over economic and political nuisances. I particularly find the news desk section helpful, it moves away from the campaign aspect of the main site towards discussion. A recent article by Tom Burke  was particularly helpful, where he highlighted the need to scrutinise safety legislation worldwide before promoting a global nuclear programme to deal with climate change.

 

Burke specifically questioned the safety of the ambitious nuclear programme in China who are planning to quadruple nuclear capacity in 7 years. Such fears resonate strongly with myself, nuclear power would be a useful part of our future energy mix but how big a part it is granted surely depends on whether safety can be maintained with rapid global proliferation 

This is where Greenpeace are refreshing, they argue largely from a global perspective, promote sustainable living and put the environment first. Many other articles look at nuclear power in terms of national policy, and mostly ignore a reduction in consumption as a way to open up alternatives, away from higher yielding non-renewables.

Horizon Nuclear Power

On the other end on the spectrum is Horizon Nuclear, which is in fact an energy supplier currently building two nuclear power stations in Oldbury, South Gloucestershire and Wylfa in Anglesey. I largely include them, as whilst the site is never going to offer vibrant political debate, it is a useful stopgap to educate yourself in nuclear power generation, as well as the arguments for a nuclear future in Britain. Under the Nuclear facts section it addresses a series of questions a nuclear sceptic might ask, the responses are obviously pro nuclear, but they are truths that need to be considered.

“70% of low carbon electricity in the UK comes from Nuclear”

The website also gives some background to the infrastructure of nuclear power stations. I beleive it is good to have at least some understanding of how the technology works before siding with the negative connotations, often ascribed to phrases like ‘waste disposal’, ‘decommissioning’ and ‘radiation containment’.  

Grist

Grist is an online environmental magazine based in Seattle. It has discussions on a plethora of environmental issues., It is certainly green but unlike Greenpeace it's coverage is not predictable, and its debates are often dynamic. In terms of Nuclear power whilst recently many of its articles have been against,, it has no clear agenda on the issue and is open to wide ranging debate. Much of the content is serious but with a refreshing humour and colloquialism, which must be said, is lacking elsewhere. Perhaps where I find Grist most helpful is that it encompasses and links such a wide range of environmental topics, and really encourages a multi-disciplinary approach to environmental issues. An article on Nuclear power I would particularly recommend is http://grist.org/nuclear/2011-04-26-unsure-about-nuclear-power-here-are-5-questions-you-must-answer/