Hunterston B power plant was shut down earlier this month amid fears regarding temperature controls. This shut down comes within only a few weeks of the plant reopening following the Nuclear Installations Inspectorate (NII) concluding that the plant should be allowed to operate once more. Hunterston B had been shut for almost 6 months to allow repairs to be carried out for cracked heat exchangers. Ironically, in its periodic safety review, the NII provisionally stated that both Hunterston B and its sister plant Hinkley Point B power station, would be allowed to extend their lives from 2011 to 2017. This was on the proviso that the plants invested £4.5m on upgrading and repairing their premises.

The decision to provisionally extend the lives of these power stations may need to be reconsidered in light of this further shut down. Currently nuclear power accounts for about 40% of all electricity generated in Scotland. The question arises of what Scotland would do to fill the deficit in electricity should Hunterston B close in 2017, 2011 or sooner.

Nuclear – the Scottish position

The new Scottish Government have indicated that Scotland can and ideally should phase out nuclear power. While most energy-related powers remain reserved to the UK Government, some powers have been devolved, such as the promotion of renewable energy, energy-efficiency and micro-generation and the issuing of planning consents. This means that a proposal to build a new nuclear power station in Scotland would need the consent of the Scottish Ministers. A Scottish Government statement indicated their approach, "If an application were to be submitted for a new nuclear power station that would be for Scottish Ministers to determine. We would be obliged to look at it – but given our policy position, our generating capacity, our multiplicity of energy sources and our strong alternative strategies such an application would be unlikely to find favour with this administration".

The new Scottish Government opposes nuclear power for a variety of reasons. Safety concerns are paramount, with fears of a terrorist attack or nuclear accident if further nuclear power stations are built. In addition the claimed cost and environment benefits of nuclear power are also questioned. While nuclear power was once heralded as being 'too cheap to meter', a recent energy review commissioned by the SNP states that when considering clean-up costs nuclear power ceases to be cheap, with some £90 billion estimated to be necessary to clean up waste from existing stations in the UK.

As for the environment, the Scottish Government has suggested that as uranium use continues the carbon dioxide produced in the process of acquiring it will increase as it becomes more rare. It has been estimated that in 50 years time the carbon dioxide produced by the nuclear process will be at the same level as a gas turbine generator producing the same amount of energy.

However, it appears that Scottish Government policy is not intractably against the extension of the lives of existing nuclear stations. It has been made clear that the Scottish Government will not stop British Energy extending the lifetime of nuclear plants if the NII consider this safe. There is a chance that Torness power station might be able to extend its operating life by between 5 and 10 years, potentially enabling the plant to remain open until 2033. If this extension transpires, it would reduce the potential energy gap that might arise should Hunterston B require to be shut early. It looks unlikely that Torness will close in the near future, thus halving the potential 2.5 GW deficit in electricity generated that would arise should both Hunterston B and Torness be closed.

The approach to nuclear power by the UK Government in the Energy White Paper published in May differs from that of the Scottish Government. The White Paper considers that in a bid to achieve the objectives of avoiding climate change and ensuring security of our energy supplies, the key is to maintain a diverse portfolio of energy sources. The White Paper agrees with the fourth report of the Intergovernmental Panel on Climate Change that "nuclear power could have a role to play alongside other low carbon energy sources in reducing carbon emissions." The UK Government see nuclear as a safe, clean and predictable source of electricity.

Crucially though, decisions must be taken quickly on whether new nuclear power should be developed. The White Paper estimates that given the large burden of consents required under planning law, such as Environmental Impact Assessment and Strategic Environmental Assessment, the first new nuclear power stations would not appear until 2020. This would mean that, even if new nuclear stations are given the "go-ahead", should Hunterston B shut at any point up to 2017, there would be a shortage of electricity generated from nuclear power.

Alternative energy sources

But what green energy sources could Scotland rely on to replace nuclear power? A variety of options such as renewables and technologies such as carbon capture and storage exist.

Hydro
The most established form of renewable energy, both worldwide and in Scotland, is hydro-electric power. Hydro-electric power has a number of advantages over other energy sources, including eliminating the need for fuel and emissions of greenhouse gases. Nonetheless, it can be disruptive to local aquatic ecosystems. Despite Scottish and Southern Energy's current Glendoe Hydro Scheme project which is set to begin generating an estimated 100MW (enough electricity to supply 250,000 homes) of electricity in 2008, it is unlikely that there will be a raft of large scale developments in the future due to most commercially viable sites being already utilised. In addition to such large scale projects, small-scale hydro power schemes are another option. Such a scheme is ideal for the supply of off-grid electricity to isolated rural communities.

Wind
Apart from hydro-electric power, the development and deployment of wind power is perhaps the most visible element of Scotland's move towards renewable energy. The main driver behind such development has and continues to be the Renewables Obligation (Scotland) (ROS), which places an obligation on electricity suppliers to provide an increasing amount of the electricity supplied from renewable sources. In 2007 there were 43 onshore wind projects operating in Scotland with an installed capacity of 1GW. By 2010 it is anticipated that Scotland will have 94 operational projects with an installed capacity of 2.5GW providing 12% of Scotland's electricity needs.

Whilst this energy is clean it is not without problems. The two major barriers to maximising wind are the current planning system and our energy networks. Scotland's planning system is severely under resourced and due to the numerous statutory consultees involved, the system does not facilitate a quick process. Furthermore Scotland's electricity grid network requires investment to enable essential upgrades to take place to allow new generation to connect to the grid. Such upgrades require Ofgem and Scottish Executive approval. This is another process which does not yield quick results.

The Scottish Executive has recently made changes to the ROS to provide more incentives for other forms of renewable energy such as deep water offshore wind, wave power, tidal stream and biomass projects. It introduced a banded obligation on suppliers requiring a minimum amount of electricity to be sourced from wave and tidal sources.

Marine
Apart from wind, marine energy, such as wave and tidal, if properly exploited, could produce 0.16 GW of Scotland's electricity by 2010. However the pace of marine development to date has been slow, and there is a risk that Scotland could lose a major economic opportunity in marine renewables to other competing countries such as Portugal. The same barriers of planning and grid access that affect wind also apply to marine energy.

Bio-energy, solar and heat
In addition to marine, other renewable technologies such as bio-energy, solar heating and heat pumping could be exploited. However unlike other forms of renewable energy, support and incentive mechanisms for renewable heat are at an early stage and require further development.

It is clear that a diverse range of renewable sources of energy exist in Scotland, and if exploited effectively, could provide a significant contribution to any gap created by the closure of either of Scotland's nuclear power stations. Moreover, it is important to note that a variety of sources of renewable energy are vital as diversity can act as a substitute for continuity of supply. In order to achieve such ambitions, issues associated with planning and grid access require to be addressed.

Carbon Capture and Storage
Apart from renewables, another area that both the Scottish Executive and other interested groups consider key in Scotland's nuclear-free energy future, is Carbon Capture and Storage. Carbon Capture is a process where carbon dioxide is extracted from the gas used to fuel a power station and is buried in the sea-bed by pumping it into an oilfield. This process has the additional benefit of potentially increasing pressure in the oilfield, thus allowing an increased amount of oil to be recovered. Such a project has been planned for the gas used to fuel the Boddam Power Station near Peterhead. Carbon would be extracted prior to its delivery to the power station and would be pumped out to the Miller Oil field. This project would provide a "green" source of electricity to 750,000 homes and around 1.8 million tonnes of carbon would be stored, which is approximately the same as the combined carbon dioxide savings of all the Scottish windfarms. The success of such schemes will depend on how the UK government intends to provide support. Following the recent publication of the Energy White Paper in May, the details of such support are still some way from being settled.

Scotland's energy future

It is clear that Scotland will have to rely increasingly on a diverse portfolio of energy sources which may or may not include Nuclear in the long term. In order to maintain security of supply whilst reducing carbon emissions, it is important that alternative sources of energy are developed and exploited effectively and the current barriers to such development must be addressed. It remains to be seen whether the new Scottish Government's ideas for filling the nuclear gap will result in a viable and secure supply of electricity.

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