Nuclear Power in Spain

(Updated February 2014)

  • Spain has seven nuclear reactors generating a fifth of its electricity.
  • Its first commercial nuclear power reactor began operating in 1968.
  • There are plans for renewed uranium mining.
  • Government commitment to the future of nuclear energy in Spain has been uncertain, but has firmed up as the cost of subsidising renewables becomes unaffordable.

Electricity consumption in Spain had been increasing steadily until 2008 but has since levelled off, and in 2012 it declined 1.9% due to Spain's economic recession. Per capita it is about 5200 kWh/yr.

Electricity production in 2012 was 297 billion kWh gross, 61.4 billion kWh (21%) of this from nuclear power, 73.2 TWh (25%) from gas, 55.9 TWh (19%) from coal, 49.1 TWh (16.5%) from wind, 24.1 TWh (8.1%) from hydro, 11.9 TWh (4%) from solar, and 5.2 TWh from biofuel and wastes. Spain is essentially an island separate from the EU grid – up to 2% of power can be imported from France and a similar amount from Portugal, but over 2008-11 there were significant net exports (8 TWh in 2010, 6 TWh in 2011), mostly to Portugal and France but also to Morocco through a 1400 MWe interconnector which can also occasionally draw upon that country's hydro resources and indirectly on Algeria. Electricity self-sufficiency is a major policy consideration.

Total generating capacity was 103 GWe in 2011, 7.4 GWe of this nuclear. Wind capacity at the end of 2011 reached 21.5 GWe, with a guaranteed feed-in tariff. In February 2012 wind contributed over 20% of electricity supply, with peak input of 17 GWe, and over 2013 it supplied 20.9% of electricity, a record, and matching nuclear power.

Solar has also been promoted with a feed-in tariff of about EUR 30 c/kWh, but the take-up was so high that the government had to renege on its subsidy commitments in 2010 after investments had been made, almost halving those for large plants. The country has spent an average of EUR 4.75 billion per year on renewables subsidies since 2004. The government announced that it would award no further feed-in tariff contracts after the end of 2012 for special regime suppliers – renewables and small generators, which have priority market access. See section on Energy Reform Bill below.

Nuclear power and industry development

In 1964 construction started on the first of three nuclear power reactors – Jose Cabrera, Zorita, a small pressurised water reactor. Two years later construction of Santa Maria de Garona, a medium-sized boiling water reactor was started, followed two years later by Vandellos 1, a medium-sized gas-cooled reactor similar to UK's Magnox units. This first generation of Spanish units – all turnkey projects – gave practical experience with three different designs, and led to a focus largely on PWR types in the 1970s.

In 1972 ENUSA (Empresa Nacional del Uranio, SA, now now ENUSA Industrias Avanzadas SA), a state-owned company, was set up to take over all of the nuclear front-end activities.

In the early 1970s construction was started on a second generation of seven reactors, five of which were completed. These involved local engineering companies Empresarios Agrupados and INITEC and the state-owned manufacturer ENSA (Equipos Nucleares SA).

In the early 1980s, construction of a third generation of five plants was started, but following a 1983 moratorium, only two were completed – Trillo 1 and Vandellos 2. In 1994 the moratorium was confirmed and five units under construction were abandoned. 

Nuclear plant ownership and operation is mostly by the Spanish-based but now international utility Endesa SA (originally Empresa Nacional de Electricidad S.A) and Iberdrola. Endesa is 92% owned by Italy's Enel. Endesa and Iberdrola have a joint venture operating company: Asociacion Nuclear Asco-Vandellos (ANAV) which covers the 40% of the country's nuclear capacity, in Catalonia. Another joint operating company is Centrales Nucleares Almaraz-Trillo (CNAT), covering the central and west capacity. Centrales Nucleares del Norte (Nuclenor) owns and operated the Santa Maria de Garona plant in the northern province of Burgos. Nuclenor is also owned by Iberdrola and Endesa, and pioneered nuclear generation in Spain. 

Spain is notable for power plant uprates. It has a program to add 810 MWe (11%) to its nuclear capacity through upgrading its nine reactors by up to 13%. For instance, the Almaraz nuclear plant is being boosted by more than 5% at a cost of US$ 50 million. Some 519 MWe of the overall increase is already in place.

Cofrentes was uprated 2% in 1988, another 2.2% in 1998, 5.6% in 2002 and 1.9% in 2003, taking it to 112% of original capacity. Tentative plans will take it to 120% later in the decade.

Licence renewal for the Santa Maria de Garona plant came up for review in 2009, and in June the Nuclear Safety Council (CSN) recommended that a 10-year extension be granted, to 2019. The CSN said that plant owner and operator Nuclenor had implemented a comprehensive work program to keep the 40-year old reactor fully serviceable, having spent some €155 million on it. The Socialist government, with a policy then of closing down Spanish nuclear plants as early as possible, granted only a four-year licence extension, to July 2013. In January 2012 the new conservative government referred the matter back to CSN with a view to revoking the 2009 decision and allowing operation to 2019. CSN again approved this and in July 2012 the government removed the 2013 operational limit, subject to Nuclenor renewing the licence. 

However, Nuclenor delayed its application until new government rules and taxes were specified, since €480 million in investment would be required to take the plant to mid 2019. Pending government plans involved heavy taxes* – 7% – on electricity generation, amounting to some EUR 1 c/kWh for nuclear, plus a tax of €2190 per kilogram on used nuclear fuel discharged – about €315 million per year across the industry. In addition, utilities must make provision in their accounts for partially used fuel still in the reactor – this would amount to over €500 million per year. Having missed the September deadline to apply for licence renewal from July 2013, Garona was shut down and promptly defueled in December 2012, rather than paying taxes on the plant of €153 million in 2013 and €374 million to 2019, required under the energy reform bill which was passed in December. In May 2013 Nuclenor approached the government to seek a resolution of the impasse, which might allow the reactor to restart. The CSN said it supported the appeal, and the Ministry should allow Nuclenor to submit a request for a one-year extension of its operating licence before June. However it would need to complete some safety modifications before loading fuel. The Ministry responded in mid June by confirming the mid-2013 shutdown, and saying it was “based solely on economic considerations”. 

* The higher taxes on power generation are to address an €24 billion energy tariff deficit after more than a decade of selling electricity at regulated rates which do not cover costs, with high subsidies on renewables – some €9 billion per year. 

In February 2014 cabinet approved a royal decree that allows recently-shutdown plants to apply within 12 months for their operating licences to be renewed, if the shutdown was not for safety reasons. This could open a possibility of restarting Garona if the taxes were waived, and if the company was prepared to spend the €480 million on upgrading.

Licence renewal for Almaraz 1&2 came up for review in 2010, and in April the CSN recommended that a 10-year extension be granted, to 2020. It said it had verified that the plant owners – Iberdola, Endesa and Union Fenosa – had kept commitments made at the last extension in 2000, and added that their decision was based on a thorough review of the plant's condition. The Ministry of Industry, Tourism & Trade then approved the CSN recommendation. In January 2011 the government approved 70 MWe uprates for both reactors, with 68 MWe for unit 1 being imminent, the engineering work having been already done.

In June 2010 the CSN recommended a 10-year licence extension for Vandellos 2, and this was approved by the Ministry in July. In February 2011 it recommended a 10-year extension for Cofrentes, and in July 2011 it recommended the same for Asco 1&2. These were agreed in March and September respectively. Another licence renewal is due in 2014.

In February 2011 parliament removed a legal provision limiting nuclear plant operating lives to 40 years, and early in 2012 an industry report recommended in principle 20-year life extensions.

The Socialist government to 2011 came to power on an anti-nuclear platform, but apart from opposing the renewal of licence for the Santa Maria de Garona plant, an early BWR-3 model, it was increasingly positive about nuclear power. In 2011 the responsible minister said that nuclear plants are "essential for the supply of electricity in Spain" and that almost all nuclear power units "will be open, operating and even repowering" until 2021. Also he said that "nuclear energy will be useful as a source of electricity for cars," which the government was promoting, hoping to have one million electric vehicles on the road by 2014. However, that government remained opposed to new nuclear plant construction. The Socialist government's anti-nuclear policy was never translated in to legislation.

The November 2011 election brought about a change of government which revisited the decision to close Garona, potentially allowing operation to 2019 (but see above).

Power reactors operating in Spain

Reactors Type Net MWe First power Commercial operation Owner (%); operator Licence expires
Almaraz 1 PWR 947 (1015) 1981 1981 Iberdrola 53%, Endesa 36%, Union Fenosa 11%; CNAT 6/2020
Almaraz 2 PWR 956 1983 1984 6/2020
Asco 1 PWR 996 1983 1984 Endesa (100%); ANAV 10/2021
Asco 2 PWR 992 1985 1986 Endesa (85%); ANAV 10/2021
Cofrentes BWR 1063 1984 1985 Iberdrola (100%); Iberdrola 3/2021
Trillo 1 PWR 1003 1988 1988 Iberdrola (48%); CNAT 11/2014
Vandellos 2 PWR 1045 1987 1988 Endesa (78%); ANAV 7/2020
Total (8)   7002 MWe        

The Program of Advanced Nuclear Plants is working on the development of Westinghouse AP 600 and GE Advanced Boiling Water Reactors. Spain is also participating in the development of European Utility Requirements (EUR) in relation to advanced nuclear technology and is part of the International Atomic Energy Agency's INPRO project.

Energy Reform Bill

The Energy Reform Bill passed in December 2012 threatened the viability of renewable projects as subsidies were reduced, and may increase dependence on coal and also imported gas. Early in June 2013 the government announced substantial reduction in the renewables subsidies since they accounted for almost half of the €20 billion annual costs of the nation's electrical system, and capped retail tariffs were insufficient to pay for the open-ended cost of escalating renewable inputs. Subsidies for renewables totalled about €9 billion in 2012 and €9.3 billion in 2013. A deficit of €30 billion had built up since 2005, according to the energy and competition regulator CNMC.  The 2012 reforms had started to address this deficit, then in July the Ministry of Industry, Energy and Tourism introduced further ‘definitive reforms’ to reduce the deficit by €4.5 billion per year. These measures will cost utilities €2.7 billion per year and consumers €400 million in 2013 and €900 million per year thereafter, while the government will cover a further €2 billion in 2013 and €900 million per year thereafter of costs. Solar companies are expected to be worst affected, due to debt load estimated at €30 billion, and widespread financial distress is predicted by solar and wind industry groups. In 2000, the government had promised more than 20 years of large subsidies, and investment proceeded on this basis. In May 2013 renewables received an average subsidy of €100/MWh. The reforms remove the feed in tariffs system and substitute a new Regulated Asset Value-based system (or "reasonable profitability" system) and will cut the payments for renewables by €1.3 to 1.4 billion per year. At the start of 2014 the impact of the switch to capacity-based incentives was unclear.

Uranium mining

Uranium was discovered in Salamanca during the 1950s. Production commenced in 1974 at ENUSA's Fe mine, which grew to become the largest uranium mine in the Iberian Peninsula. It produced over 4000 tU. The mine closed in 2000 due to low uranium prices, though minor output continued to 2002 from decommissioning, and the mining areas have since been restored. One large pit and three small ones are involved.

Australian-based Berkeley Resources owns uranium properties in Salamanca province and also pursued a joint venture with ENUSA to develop the Salamanca State Reserves. Its own Salamanca 1 project has JORC-compliant indicated and (mostly) inferred resources of 11,000 tonnes of uranium in the Retortillo area. A preliminary feasibility study indicated a 10-year mine life from open pit and bacterial heap leach producing 550 tU/yr at $88/kgU

Berkeley earlier proposed using the Quercus mill (Saelices el Chico) which was operational to 2003 to process production, partly from heap leaching. The mill, with capacity of about 800 tU/yr, has been on care and maintenance since 2003. In 2006 Berkeley negotiated a tentative sales agreement with Areva, but this terminated in 2010.

Apart from this Salamanca 1 project, in December 2008 Berkeley agreed with ENUSA to undertake an 18-month feasibility study on restarting uranium mining, focused on the Aguila and Alameda areas of the state reserves close to the Quercus mill. Berkeley has the right to acquire up to 90% of ENUSA's mining and exploration assets, including the Quercus mill which would then form part of its Salamanca Project. Following Berkeley's notification in January 2011 that it wished to proceed with mining the state reserves, ENUSA had until 29 February 2012 to form this new joint venture company to take forward the $228 million proposal. The new company was not incorporated by then and Berkeley took ENUSA to the Paris-based International Court of Arbitration of the International Chamber of Commerce. Berkeley is claiming compensation for a total of over US$200 million for the damages and losses caused by ENUSA’s breach of the Co-operation Agreement. In April 2012 ENUSA said that it considered that the project was not viable, and therefore any JV company was irrelevant.

The ENUSA state reserves in the Aguila Area include three significant deposits – Sageras, Majuelos and Palacios, two of which have been previously mined as Mina Fe. These have 8000 tU (JORC-compliant), half of this as measured and indicated resources. 

In July 2012 a new agreement between Berkeley and ENUSA gave Berkeley full rights in two state reserves including Alameda and Villar deposits, with known resources of 8880 and 1710 tU respectively at av 0.0465%. The extensively-drilled Alameda and Esperanza/Villar deposits, are about 10km from Aguila, and contiguous with other Berkeley leases. They will be integrated into Berkeley’s Salamanca 1 project. A 2.5% royalty will apply. However, Berkeley waives its rights to mine in any state reserves where ENUSA has undertaken rehabilitation, or to use the Quercus mill. The 2009 cooperation agreement was terminated.

Berkeley's own Retortillo area, with Retortillo, Santidad and some smaller deposits, is 25 km northeast of Aguila. Pending resolution of the ENUSA JV discussions, in mid October 2011 Berkeley turned its attention back to its own deposits where exploration ceased in 2008, and applied for a mining licence for these as Salamanca 1, using bacterial heap leaching rather than toll processing through the Quercus mill. A preliminary feasibility study was completed in 2011 showing pre-mining cost of EUR 62.5 million and mine life of ten years producing 9750 tU. Total Salamanca 1 resources were 11,050 tU in December 2011 (without the two state reserves). A prefeasibility study for Alameda and Retortillo in 2013 was based on open pit mining, heap leaching, a central processing plant at Retortillo and a remote ion exchange operation at Alameda, with resin trucked top the main plant. Initial capital cost would be US$ 95 million, followed by $74 million to develop Alameda. It indicated an 11-year mine life averaging 1000 tU/yr at $25/lb U3O8. A definitive feasibility study is planned over 2014.

Overall, Berkeley now claims rights to 50,200 tU in the expanded Salamanca project (including two state reserves) at average grade 0.036%U, with 200 ppm U3O8 cut-off, though the basis of this figure is not clear from December 2011 resource data.

Berkeley paid EUR 5 million for the ENUSA database and the government has approved the overall agreement. After pursuing alternatives*, Berkeley has raised A$ 55 million through a share issue and will pay EUR 20 million for the 90% equity in ENUSA assets if and when these are transferred into a new joint venture company which will develop the project. This JV will be 90% Berkeley and 10% ENUSA. A feasibility study is due for completion in mid-2012. Polo Resources funded much of the feasibility study through a share placement.

* In August 2010 Berkeley agreed to sell 35% of the Salamanca project to KEPCO for $70 million, but the deal was aborted in November 2010. Also the Russian steel and mining group Severstal was considering a full takeover offer.

Apart from Salamanca, Berkeley has some other projects including Caceres VI not far away with 4000 tU inferred resource (based on ENUSA work), and two other in the east of the country.

Under its agreement with ENUSA, Berkeley would pay 2.5% royalties on uranium produced from the three ENUSA properties, plus 2.5% of revenues from all uranium which is processed through the Quercus plant. However in 2012 the regulator CSN refused further extensions to ENUSA and ordered the decommissioning of the Quercus mill. 

Canada-based Mawson Resources is also active in exploration in Salamanca, focused on the Don Benito prospect.

The 1600 tonnes of uranium used in Spain each year is imported. ENUSA has a 10% stake in mining in COMINAK, mining at Akouta in Niger.

Fuel cycle facilities 

There are no conversion or enrichment facilities in Spain, but ENUSA owns 11% of Eurodif, with a large diffusion enrichment plant at Marcoule in France. It also contracts for other conversion and enrichment services abroad.

ENUSA's Juzbado plant in Salamanca, commissioned in 1985, produces BWR and PWR fuel elements for Spain's reactors and also supplies other customers in Europe. In 2008 more than half of its 921 fuel assemblies were exported.

GNF ENUSA Nuclear Fuel S.A. (GENUSA) is jointly owned by Global Nuclear Fuel-Americas, LLC (a GE-led joint venture with Hitachi and Toshiba) as majority owner, and ENUSA. It was set up in 1989 and markets BWR fuel in Europe.

In 1991, ENUSA with Westinghouse Electric Corporation and British Nuclear Fuel Ltd (BNFL), created the European Fuel Group (EFG), with the purpose of a joint action in the European PWR nuclear fuel market.

Radioactive Waste Management

ENRESA (Empresa Nacional de Residuos Radiactivos SA) was established in 1984 as a state-owned company to take over radioactive waste management and decommissioning of nuclear plants. It is now the only state-owned part of the nuclear fuel cycle in Spain.

It drew up a General Plan for radioactive wastes which was approved by parliament in 1999. Its is based on nuclear power plant lives of 40 years, and addresses the need to manage almost 200,000 cubic metres of low and intermediate-level wastes and 10,000 cubic metres of spent fuel and other high-level wastes.

ENRESA's low and intermediate-level waste storage facility is at El Cabril, Cordoba. It has operated since 1961.

Since 1983 Spain's policy has been for an open fuel cycle, with no reprocessing. The 1999 plan for spent fuel envisaged initial storage at each reactor for ten years. Some temporary storage for dry casks at Trillo up to 2010 was planned, and establishment of a longer-term centralised facility would follow. Meanwhile research would progress on deep geological disposal as well as transmutation, with a decision on disposal to be made after 2010. Granite, clay and salt formations are under consideration. 

In mid-2006 Parliament approved ENRESA's plans to develop a temporary central nuclear waste storage facility by 2010, and the CSN approved its design, which was similar to the Habog facility near the Borssele power plant in the Netherlands. In December 2009 the government called for municipalities to volunteer to host this EUR 700 million Almacen Temporal Centralizado (ATC) facility for high-level wastes and used fuel. The government offered to pay up to EUR 7.8 million annually once the facility is operational. It is designed to hold for 100 years 6700 tonnes of used fuel and 2600 m3 of intermediate-level wastes, plus 12 m3 of high-level waste from reprocessing the Vandellos 1 fuel. The facility is to be built in three stages, each taking five years. Asco and Villar de Canas were two towns among eight that volunteered, attracted by the prospect of EUR 700 million over 20 years and the annual direst payments, plus many jobs. A campaign of fearmongering has been mounted by nuclear detractors to dissuade residents of the eight towns, and some regional governments are also opposed.

In September 2011 the Ministry for Industry announced its selection and rankings:

  • Zarra (Valencia) 736 points
  • Asco (Tarragona) 732 points
  • Yebra (Guadalajara) 714 points
  • Villar de Canas (Cuenca) 692 points

In December 2011 the Ministry announced that Villar de Canas had been selected, though only a 60-year storage period was mentioned. Pending construction, used fuel remains at individual power plants. Several, including Asco and Trillo (as well as Jose Cabrera), are using dry storage.

Waste management and decommissioning is funded by a levy of about 1% on all electricity consumed.


Vandellos 1, a 480 MWe gas-graphite reactor, was closed down in mid 1990 after 18 years operation, due to a turbine fire which made the plant uneconomic to repair. In 2003 ENRESA concluded phase 2 of the reactor decommissioning and dismantling project, which allows much of the site to be released. The cost of the 63-month project was EUR 93 million. After 30 years Safestor, when activity levels have diminished by 95%, the remainder of the plant will be removed.

In April 2006 the 142 MWe Jose Cabrera (Zorita) plant was closed after 38 years operation. Dismantling the plant will be undertaken over six years from 2010 by Enresa – total cost is estimated at EUR 135 million. About 4% of the plant's constituent material will need to be disposed of as radioactive waste, the rest can be recycled, including 43 tonnes of internal components.

In December 2012 the Santa Maria de Garona plant, an early BWR-3 model of 446 MWe net, operating since 1971, was closed down after 41 years operation. Nuclenor operated the plant on behalf of its owners, Iberdrola and Endesa. However, there appears to be some possibility of restarting the plant (see main section above).

Regulation and safety

In 1980 the Consejo de Seguridad Nuclear (CSN – nuclear safety council) was set up to take over both nuclear safety and radiological protection matters. The CSN was overhauled in 2007, following an incident in 2004 at Vandellos 2, and the scope for penalties increased.

In 2009 Endesa was fined EUR 15.4 million over a radioactive release incident during a refuelling operation at Asco 1 in 2007. There were six charges of breaching safety rules. The incident was rated 2 on the INES scale.

Licensing is under a 1964 law (amended) and 1999 regulations by the Economic Ministry, advised by CSN and Ministry of Environment.

Civil liability for nuclear damage is covered under international conventions to which Spain is party – the IAEA Vienna Convention and the OECD Paris and Brussels Conventions. Operators need to cover EUR 150 million.


Spain is a party to the Nuclear Non-Proliferation Treaty (NPT) as a non-nuclear weapons state. Its safeguards agreement under the NPT came into force in 1967 and in 1985 it came under the Euratom safeguards arrangement. In 1998 it signed the Additional Protocol in relation to its safeguards agreements with both IAEA and Euratom.

Main References:

IAEA, Country Nuclear Power Profiles.


Berkeley Resources