Jaderná energie ve Švédsku (Nuclear energy in Sweden)

• Sweden has 10 operating nuclear power reactors providing over 40% of its electricity.
• In 1980, the government decided to phase out nuclear power. In June 2010, Parliament voted to repeal this policy.
• The country's 1997 energy policy allowed 10 reactors to operate longer than envisaged by the 1980 phase-out policy, but also resulted in the premature closure of a two-unit plant.
• Sweden has a tax discriminating against nuclear power - now about 0.67 Euro cents/kWh, which makes up about one-third of the operating cost of nuclear power.

Sweden's electricity consumption has been rising and it has one of the world's highest individual levels of consumption. Over 40% of domestic production is nuclear, and up to half hydro, depending on the season (affecting hydro potential). In 2008, Sweden generated almost 146 billion kWh, of which 42% was from nuclear (61.3 billion kWh).

Electricity imports and exports vary according to season, with Finland, Norway and Denmark providing the main traffic. In 2004, net exports were 2 TWh, and in 2005, 7.4 TWh. In 2006, net imports were 6 TWh, and in 2007, net imports were 1.3 TWh. Per capita consumption is about 14,800 kWh/y.

The state utility is Vattenfall AB, and private utilities include E.ON Sweden AB and Fortum Oy (majority-owned by the Finnish government).

Up to the late 1960s, there was a focus on hydro electricity to power Sweden's industrial growth. In 1965, it was decided to supplement this with nuclear power, to avoid the uncertainties of oil prices and increase the security of supply. The policy was reinforced by the oil shocks of the early 1970s, at a time when Sweden depended on oil for about one fifth of its electricity and electricity demand was increasing by 7% per year. Hydroelectric output depends very much on seasonal precipitation: it was 78 TWh in 2000, 62 TWh in 2006, and 69 TWh in 2008, with most of the balance from nuclear.

In the mid-1970s, the nuclear push became a political issue, and 1977 legislation was passed to ensure proper waste management. This provided the basis for Sweden's world leadership in management of used fuel (particularly for those countries not reprocessing it).

Sweden has been an enthusiastic supporter of measures to improve world environmental quality. Among many others, at the Earth Summit in Rio de Janeiro in 1992, Sweden committed itself to stabilise carbon dioxide emissions at 1990 levels by 2000, and this was reaffirmed in 1995 at the first Conference of Parties to the United Nations Framework Convention on Climate Change (UNFCCC) in Berlin. The fact that those levels in 1990 were only 60% of those of the 1970s was due to nuclear energy replacing most oil for electricity generation.

Nuclear industry development in Sweden

In 1947, the government established an atomic energy research organization, AB Atomenergi. The country's first experimental reactor, R1, was commissioned in 1954. Then, in 1956, a commission recommended development of a nuclear power program also producing heat. Atomenergi commissioned two test reactors - one 50 MWth (R2) reactor and one 1 MWth (R2-0) reactor - located near Nyköping in 1960 to further this goal. (They were operated by Studsvik AB and shut down in mid-2005.)

In 1964 Atomenergi and Vattenfall together commissioned the small (65 MWth and 10MWe) Agesta heavy water reactor to deliver heat and a little electricity to Stockholm. It operated until 1974. The two organisations then started to build the larger (140 MWe) R4 Marviken heavy water reactor supplied by ASEA, but the project was aborted just before fuel loading.

Following a proposal for a small boiling water reactor (BWR), a Sydkraft-led consortium (OKG AB) ordered a 460 MWe BWR unit - Oskarshamn 1 - from ASEA in 1966. This was the first western light water reactor designed and built without requiring a licence from US vendors. It started up in 1972.

In 1968, Vattenfall ordered Ringhals 1, a 750 MWe BWR from ASEA, and Ringhals 2, an 800 MWe PWR from Westinghouse, in order to compare the technologies. Two further PWRs were built at Ringhals.

In 1969, OKG ordered Oskarshamn 2 and Sydkraft ordered Barsebäck 1 with an option for unit 2, all from ASEA Atom. In the 1970s Vattenfall cooperated with other utilities to build the Forsmark nuclear plant.

Six reactors entered commercial service in the 1970s and six in the 1980s. The 12 reactors were at four sites around the southern coast. One Barsebäck unit closed in 1999 and the other in May 2005. Sweden now has 10 nuclear power reactors providing almost half its electricity from 9400 MWe of capacity. Nuclear power produced 77.5 billion kWh in 2004 (51% of total electricity production), 61.3 billion kWh (42%) in 2008, and 50.0 billion kWh (37%) in 2009. The percentage changes from year to year depending on hydro resources following winter precipitation.

Sweden's nuclear power reactors

In connection with debate on closure of Barsebäck (see Appendix 1: Barsebäck Closure) in the late 1990s the government imposed a capacity tax on nuclear power, at SEK 5514 per MWth per month, which worked out at about 2.8 to 3.0 ore/kWh (0.30-0.32 Euro cents/kWh) potentially produced, penalising nuclear relative to other sources. In January 2006, the tax was almost doubled to SEK 10,200 per MWth (about 0.6 Euro cents/kWh). Early in 2008, it was further increased by 24% to SEK 12,684 per MWt from 2008 - total SEK 4 billion (EUR435 million, meaning about 0.67 Euro cents/kWh). This makes up about one-third of the operating cost of nuclear power in Sweden.

Sweden's electricity imports have normally balanced exports, with a small net flow in from Norway and out to Finland. In 2005 - a good year for hydro - net exports were 7 billion kWh mainly to Finland and Denmark, while in 2006 - a poor year for hydro - net imports were 6 billion kWh. In response to Sweden's uncertainty, Finland is building a fifth nuclear reactor there. It has recently increased the capacity of its two Swedish-built nuclear reactors by 23% and that of the others by 11%. A new 800 MWe undersea transmission line is being built by 2010 to enable export of electricity to Sweden from Finland's new Olkiluoto reactor.

Boosting Swedish nuclear capacity

The government is working with the utilities to expand nuclear capacity to replace the 1200 MWe lost in closure of Barsebäck 1 & 2. By the end of 2008, some 1050 MWe had been added to the ten surviving reactors.

Ringhals

First, Ringhals applied to the Swedish Nuclear Power Inspectorate (SKI) for a major uprate on the 915 MWe unit 3, on the basis of steam generator replacement already undertaken, and more to follow as low pressure turbines were replaced in 2007. Early in 2008, it was operating at 985 MWe net. In August 2008, work was completed to allow it to operate at 1050 MWe pending approval by SKI's successor, the Swedish Radiation Safety Authority (SSM). In May 2009, SSM approved test operation at 1045 MWe. A further uprate to 1105 MWe is envisaged.

On the older Ringhals BWR unit 1, a 15 MWe uprate was completed in 2007, with another 15 MWe to follow. Ringhals 4 had a 30 MWe uprate to 935 MWe following replacement of its low pressure turbines in 2007. Exchange of high-pressure turbines and steam generators in 2011 and other work is expected to yield a further 240 MWe. The total uprate for Ringhals plant over 2005-12 is likely to be more than 450 MWe, and total some 660 MWe over 25 years to 2014.

Forsmark

At Forsmark, uprates of around 8% were carried out at each unit in the 1980s. In 2004, low pressure turbines were replaced in unit 3, giving a 30 MWe uprate, and the same was done for units 1 & 2.

A major uprate program was announced in 2004 by Forsmarks Kraftgrupp. This planned SEK 13 billion ($1.8 billion) program would have added a further 410 MWe to the plant. Following a series of safety concerns, including an incident in July 2006 (see section below on Regulation and safety), the uprate program was delayed. Upgrading work then began in the latter half of 2009 on unit 2, which would lead to a capacity increase of 120 MWe. The plan was for Forsmark 1 to be uprated by 120 MWe in mid-2011; and unit 3 would get a new SEK 900 million generator in 2014, which would contribute to a 170 MWe uprate. However, following problems with the work carried out on unit 2^c, it was decided in November 2010 to indefinitely postpone the upgrading of units 1 and 3.

Oskarshamn

In 2005, SKI approved a 250 MWe uprate of the Oskarshamn 3 reactor, to 1450 MWe net, this was confirmed by the government in January 2006, and in September 2009 SSM approved test operation at the uprated level. However, due to turbine problems, full operation at the new level was deferred until September 2011. The SKR 3.2 billion (EUR313 million) project involved turbine upgrade by Alstom as well as reactor upgrade, and will extend the plant's life to 60 years. This was approved by SSM in April 2010 and is expected to be completed in 2013 - later than originally planned. In mid-2009, OKG announced plans to uprate Oskarshamn 2 to 840 MWe and extend its life to 60 years. OKG has been preparing for the uprate since 2007 when new electrical and control systems were installed. In 2009 the turbine hall was modernized and in 2012-13 safety systems will be upgraded and the unit can start delivering the higher power - an increase from 661 to 840 MWe gross - 27%. Oskarshamn 1 has had three renovations and uprates, in 1995, 1998 and 2002.

Sweden's ambivalent energy policy

The Three Mile Island accident in the USA resulted in a decision to call a public referendum in Sweden, to remove the issue from the election campaign late in 1979. The 1980 referendum canvassed three options for phasing out nuclear energy, but none for maintaining it. A clear majority of voters favoured running the existing plants and those under construction as long as they contributed economically, in effect to the end of their normal operating lives (assumed then to be 25 years). Parliament decided to embargo further expansion of nuclear power and aim for closing the 12 plants by 2010 if new energy sources were available realistically to replace them.

The 1986 Chernobyl disaster (first recognised outside the Soviet Union at a Swedish nuclear power station) created some pressure to progress the issue of nuclear decommissioning. In 1988, the government decided to begin the phase-out in 1995, but this decision was overturned in 1991 following pressure from the trade unions.

In 1994, the government appointed an energy commission consisting principally of backbench politicians, which reported at the end of 1995 that a complete phase-out of nuclear power by 2010 would be economically and environmentally impossible. However, it said that one unit might be shut down by 1998.

This gave rise to intense political manoeuvring among the main political parties, all of them minority, with varied attitudes to industrial, nuclear and environmental issues. The Social Democrats ruled a minority government but with any one of the other parties they were able to get a majority in parliament.

Early in 1997, an agreement was forged between the Social Democrats and two of the other parties which resulted in a decision to close the two Barsebäck units, both 600 MWe boiling water reactors constructed by ASEA-Atom and commissioned in 1975 and 1977. They are only 30 kilometres from the Danish capital, Copenhagen, and have been a source of contrived concern to the Danes on that account. They were closed in 1999 and 2005 respectively - see Appendix 1: Barsebäck Closure.

The positive aspect of this decision to close Barsebäck is that the other ten reactors gained a reprieve beyond 2010, allowing them to run for about 40 years (i.e. closing 2012-2025). A phase-out program was to be decided before 2002, but remains uncertain.

In the 1970s, it was the Centre Party in Sweden that started the anti-nuclear debate culminating in the 1980 referendum canvassing three options for phasing out nuclear energy. Since then the Centre Party lined up with the three socialist parties on nuclear power, but the three non-socialist parties on other issues. Then, early in 2005 and against a background of increasing electricity prices, the leadership of the Centre Party indicated a substantial reversal of this earlier anti-nuclear position, saying that climate change must be put ahead of nuclear decommissioning. The party abandoned its alignment with the socialist parties on energy policy and fully joined the three pro-nuclear parties, so as to allow nuclear power to continue supplying a major part of the country's electricity. This view was in line with the overwhelming majority of public opinion.

These four parties - the Centre Party, the Christian Democrats, the Liberal People's Party and the (conservative) Moderate Party - formed the conservative-led Alliance for Sweden (Allians för Sverige) coalition and came to power in the September 2006 elections. The coalition was much more in tune with popular sentiment and positive about nuclear power than its predecessor. While no reactors would be closed, planning of new units was not originally on the agenda during the coalition's first term. However, several major reactor upgrades were to& be undertaken. In March 2007, the Christian Democrats changed their policy to explicitly disown the phase-out and allow for new reactors being built after 2010. Early in 2008, leaders of the Liberal People's Party called for construction of four new reactors at existing sites as replacements for those which would be retired in the 2020s. They also called for a policy focus on electric vehicles rather than biofuels.

Then, in February 2009, the Swedish coalition government said it planned to abolish the act banning construction of new nuclear reactors¹. This was narrowly approved by Parliament in June 2010, though construction will only be at existing sites and to replace the present ten units. This is part of the government's climate program, which stipulates that by 2020, renewable sources should supply half of all energy produced, the Swedish car fleet should be independent of fossil fuels in 10 years, and the country should be carbon-neutral by 2050.

Public opinion in Sweden

Public opinion in Sweden has been much tested. The first point to note is that the 1980 referendum did not canvass any option for continuing Sweden's nuclear power program. Many wish it had, just to provide a benchmark.

Since then however public opinion has steadily strengthened in favour of nuclear energy.

In April 2004, 77% of people gave top environmental priority to restraining greenhouse gas emissions, 13% to protecting unspoiled rivers from hydroelectric development, and only 7% to phasing out nuclear power. On nuclear power matters, 17% supported a nuclear phase-out, 27% favoured continued operation of all the country's nuclear power units, 32% favoured this plus their replacement in due course, and 21% wanted to further develop nuclear power in Sweden. The total support for maintaining or increasing nuclear power thus was 80% as the government tried to negotiate a phase out. This total support had risen to 83% in March 2005, with a similar proportion saying that limiting greenhouse gas emissions should be the top environmental priority.

With slightly different questions, total support for maintaining or developing nuclear power was 79% in June 2006 and fluctuated around this to June 2008 when it was 82%, comprising 40% who favoured expanding nuclear capacity and 42% who favoured continuing to operate present plants but not building more. A self-assessed 18% (26% of men, 11% of women) said in November 2007 they had become more positive towards nuclear power in the light of concerns about climate change, while 7% (4% of men, 10% of women) said they had become more negative. This may be related to 14% who thought that nuclear power was a source of CO2 with a large impact on the environment (8% of men and 21% of women)!

By February 2010 however, the positive opinion had diminished. A poll (N=1500) on behalf of the country's electricity-intensive industries showed 30% support for replacement of the current fleet of reactors as they reach the end of operating lives, plus 22% who also favoured building new reactors. Some 45% preferred a phase-out of nuclear energy. However, when asked which source of energy is best for both employment and climate, nuclear was the most popular answer, with 26%, followed by wind (21%), hydro (18%), solar (14%) and biofuels (12%)².

In late June 2010, a survey (N=1008) commissioned by the Liberal Party was reported to show overall 72% support for the government decision to allow building of new reactors, with 28% opposed³. Even among Social Democrats, who have threatened to reverse the decision if elected later in 2010, 66% of supporters were in favour of new build.

Nuclear fuel cycle

Sweden imports most of its nuclear fuel, including all enrichment. In the case of Forsmark, these have been provided: 20% Eurodif (diffusion), 60% Urenco, 20% Tenex (both centrifuge) - over 90% of energy input being from nuclear power.

Westinghouse has a fuel fabrication plant at Vasteras, which produces about 400 tonnes of BWR and PWR fuel per year.

Sweden has some uranium mineralisation but no mines. Some 200 tU was produced from a black shale deposit in Ranstad in the 1960s. Another deposit is Pleutajokk, near the Arctic Circle. Canada's Mawson Resources is investigating the Hotagen District of northern Sweden and has identified several small deposits.

Australia's Aura Energy In August 2011 announced JORC-compliant inferred resources of 243,000 tU at 0.014%U in the Alum black shales at Haggan near Storasen and Vasterasen in central Sweden. Molybdenum, nickel, zinc and vanadium are present and are potential co-products. The Haggan deposit is flat, with low mining costs, and though amenable to acid leach it has high carbonate levels, so bacterial heap leaching is being investigated. (Talvivaara Mining in Finland is planning to recover uranium by-product from bio-leaching similar black shale ore.)

Waste management

Sweden has its nuclear waste management well in hand. The Swedish Nuclear Fuel and Waste Management Company (Svensk Kärnbränslehantering AB, SKB) was set up by the nuclear utilities following the Waste Legislation (Stipulation Act) in 1977 to develop a comprehensive concept for the management and disposal of used fuel and other radioactive wastes. It is owned 36% by Vattenfall, 30% Forsmark, 22% OKG and 12% E.ON Sweden.

Some low-level waste is disposed of at reactor sites, and some is incinerated at the Studsvik RadWaste incineration facility in Nyköping.

SKB's dedicated ship, M/S Sigyn, moves the used fuel and wastes from power plants to storage or repositories.

A final underground repository (SFR) for operational (up to intermediate-level) radioactive waste and medical and industrial radioactive wastes has been operating near Forsmark since 1988. It has 63,000 cubic metre capacity and receives about 1,000 cubic metres per year. This is also one of the locations proposed by the local Östhammar community for a final high-level waste (HLW) repository.

The CLAB interim repository for used fuel (treated as high-level waste) has been operating since 1985 at Oskarshamn, and its original 5,000 tonne capacity^d has been expanded to 8000 tonnes to cater for all the fuel from all the present reactors. The used fuel is stored under water in an underground rock cavern for some 40-50 years. It will then be encapsulated in copper and stainless steel canisters^e for final emplacement packed with bentonite clay in a 500 metre deep repository in granite. In mid-2009 about 5,000 tonnes of used fuel was at CLAB.

Research at the Äspö Hard Rock Laboratory nearby has identified geological characteristics for this final deep repository. Site selection procedures from 2002 resulted in two municipalities voting to be candidate locations for a deep geological repository - Oskarshamn (Simpevarp and Laxemar) and Östhammar (Forsmark). Both these had been selected as having potentially suitable bedrock characteristics, after feasibility studies in eight municipalities. An April 2008 independent poll in both communities (N=900 in each) showed that 83% of Oskarshamn residents and 77% of those in Östhammar supported having the future repository in their own locality. Six neighbouring localities were also surveyed in 2008 and, while the majority of residents were in favour of a final repository in the neighbouring municipalities, support diminished as distance from ongoing nuclear power operations increased.

SKB announced its decision to locate the repository at Soderviken near Forsmark in Östhammar municipality, on the basis of it having the best geology, in June 2009. In April it had signed an investment agreement with both volunteer municipalities specifying investment of SKR 2 billion (US$ 245 million) in the two, with the majority going to the unsuccessful bidder, which will thereby be disadvantaged financially. SKB applied for a licence to construct the repository in March 2011. It plans to begin site works in 2013, with full construction starting in 2015, and operation after 2020.

The repository will have 12,000 tonnes capacity at 500 metres depth in 1.9 billion year-old granite. A 5 km ramp will connect to an eventual 60 km of tunnels over 4 sq km, housing 6000 copper canisters containing the used fuel. Bentonite clay would surround each canister to adsorb any leakage. The repository concept is known as KBS-3.

SKB applied for a permit to build an encapsulation plant next to CLAB at Oskarshamn in November 2006. This will be operated with CLAB and licensing is expected after 2009. Encapsulated used fuel will make its last journey from here to the repository at Östhammar.

Nuclear generators are responsible for the costs of managing and disposing of spent fuel, and must provide for those costs as they go. They pay a fee set by the government to a state fund administered by SSM to cover waste management and decommissioning. This is based on advice from SKB and has averaged SEK 0.02/kWh (0.21 Euro cents/kWh). In 2011 SSM recommended an increase in the fee due to estimating that SKB's deep SFR repository would cost more than anticipated.

Some 4.8 tonnes of metal used fuel from the R-1 research reactor has been sent to the UK's Sellafield for reprocessing in the Magnox reprocessing plant, since it cannot safely be stored long-term. Plutonium from this will be combined with the small quantity from reprocessed Oskarshamn fuel (reprocessed some years ago) and returned as MOX fuel.

Four power reactors - Agesta, Marviken (never operated) and Barsebäck 1 & 2 - are being decommissioned, along with three research reactors - R1, R2 and R2-0 at Studsvik's Nyköping site. R1 has now been dismantled.

Swedish nuclear R&D

Studsvik is a public company whose origins were in 1947 as a largely state-owned enterprise. In the 1960s, it relocated from Stockholm to Nyköping, focused on pure R&D and subsequently it became industry-funded and owned. In the 1990s, it became an international enterprise.

Studsvik's 600 kWth R1 research reactor operated 1954-70. R2-0 was a 1 MWth research reactor which operated from 1960-2005. R2 was a large (50 MWth) test reactor which operated 1960-2005. Both R2 and R2-0 were used for isotope production.

The R2 test reactor was involved with international research programs testing reactor fuel elements. It used high-enriched fuel supplied by the USA and with used fuel returned to the USA. In collaboration with CERCA in France the company was working on qualifying a high-density U-Mo fuel to enable low enrichment to be used. However, R2 was shut down in mid-2005 and its work taken over by the 20 MWth Halden heavy water reactor in Norway, operated by IFE.

Agesta (10 MWe plus 65 MWt district heating) was built as a prototype heavy water power reactor which if necessary could serve as a stopgap source of plutonium for Sweden's nuclear arsenal (which had been proposed in the 1950s). It was also known as R3 and operated 1964-74. The Marviken (R4) heavy water reactor outside Norrköping was intended for research plus power generation (140 MWe) and plutonium production but was never fuelled or operated, and work was abandoned in 1970 after six years' construction.

Government-funded R&D totalled SKR 10.5 million in 2007, focused on reactor safety as well as ensuring that Sweden maintains competence in the nuclear industry. A ban on nuclear research was removed in 2006.

Regulation and safety

An Atomic Energy Act was passed in 1956, followed by a Radiation Protection Act in 1958. The Atomic Energy Act and several others were superseded by the Nuclear Activities Act in 1984.

In the 1960s the Swedish Nuclear Power Inspectorate (SKI) was set up and became responsible for licensing, regulation and supervision under the Nuclear Activities Act. Its three divisions were reactor safety, safeguards, and research. The Swedish Radiation Protection Institute (SSI) operated under the Radiation Protection Act 1988. In mid-2008, the two organisations were merged to become the independent Swedish Radiation Safety Authority (SSM) encompassing both radiation protection and nuclear safety regulation.

In 2010 SSM commenced preparations for introducing a licensing process for new nuclear power reactors.

In July 2006, a safety-related incident at Forsmark received a lot of media coverage. It was eventually assigned a rating of Level 2 on the International Nuclear Event Scale (INES). Following a request by management of the three nuclear plants, in March 2007 the director of the International Atomic Energy Agency's Operational Safety Section met with representatives from SKI and the Swedish Radiation Protection Authority as well as management from the three plants and the Environment Ministry. This was to discuss safety culture problems and to arrange Operational Safety Team Review (OSART) missions to the Swedish reactors, the first being to Forsmark.^f

The nuclear training and safety centre (Kärnkraftsäkerhet och Utbildning AB, KSU) is a vital ancillary organization and is responsible for training staff and for liaison with the World Association of Nuclear Operators (WANO). It is part of Vattenfall but owned by all the power plants. The Analysis Group, focused on nuclear safety and with a public information role, is administered by KSU.

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