As The Engineer concludes its year-long investigation into future energy sources, Stuart Nathan asks the UK’s leading experts where the technologies are going

When The Engineer decided to make 2007 its ‘Year of Energy’, we pointed out that energy was dominating the headlines as never before, with talk of fuel shortages, the contribution of air travel to climate change, and the influence of politics on energy security. Energy, we said, was one of the major issues of our time, so we set out to look at how engineering and technology was addressing it.

It has been a fascinating journey. Over the course of the year, we’ve visited the hottest place in the solar system to look at the latest stages in the development of nuclear fusion, and the northernmost reaches of the UK, to see the latest generation of wave and tidal energy devices undergoing early trials. We’ve looked at technologies to turn straw into oil and seawater into hydrogen and how engineers are searching under the Arctic ice to unlock new oil and gas reserves. And we’ve assessed which technologies are likely to underpin the next generation of nuclear power stations in the UK.

A year on it seems, if anything, that we understated how important energy would be. It is the single most pervasive factor in technology today, and its influence extends into all our daily lives.

Wherever you stand on climate change — and the scientific consensus remains that it is human activity, literally fuelled by burning fossil fuels, that is causing it — the way we source, use, abuse, and conserve energy is set to change comprehensively in the next decades. And for engineers, it is clear no project can go ahead without taking energy into account at every stage.

It is also clear that the UK, in particular, has some hard decisions to make in the energy-generation sector. With North Sea gas now running low and many large centralised power stations, both hydrocarbon and nuclear-fuelled, reaching the ends of their lives in the next 10 years, gaps in generation capacity will have to be filled. And they will be filled with technologies that are now under development.

The entire energy landscape is more mutable now than at any time since the industrial revolution — from the methods we use to generate power, the way we distribute it around the country, to how we handle the waste products. New technologies on the horizon could completely change the picture: nuclear fusion is approaching the stage where it could be a real possibility, and wave and tidal power could unlock the potential of the UK’s geography and make an even stronger link between climate and energy. All these technologies are at a similar stage of development.

Even the energy sectors not related to electricity are in a near-unprecedented state of flux. Dwindling oil reserves and worries over security of supply are forcing attention on to new sources of transport fuel, while development of fuel cells continues to bring a ‘hydrogen economy’ model close to hand. Meanwhile, energy-efficient methods for heating and lighting homes and offices are at the top of the agenda for builders and architects.

So, to round off the Year of Energy, we decided to ask some of the scientists and engineers who have contributed to our features over the course of the year, along with other experts, their opinions on the big questions facing the energy sector.

Their complete replies can be seen here. In this article, we summarise their views on where we are, where we’re going and how the technology community can help us get there.

The future of hydrocarbons

The one area in which all our experts agreed was that, despite the increasing emphasis on reducing carbon dioxide emissions and finding more diverse sources of energy, fossil fuels will continue to play a major role in energy generation into the middle of this century. ‘Fossil fuels will continue to dominate, until there is a technology that supersedes it,’ said Paul Howarth, director of research at the Dalton Nuclear Institute, Manchester University.

From the fusion perspective Chris Llewellyn Smith, director of UKAEA’s Culham site, said that ‘as long as resources exist they are likely to be used, and we need to find ways of reducing the environmental impact’.

From the wider research point of view Prof Jim Skea, research director of the UK Energy Research Centre, claimed that fossil fuels’ contribution is likely to be ‘more than many would like’. Regardless of whether ‘peak oil’ has passed, he said, ‘it’s likely that large quantities of hydrocarbons will continue to be available at prices that people are willing to pay’.

The key technology for fossil fuels, many said, will be carbon capture and storage (CCS). If this can be developed and demonstrated successfully fossil fuels — even coal, the most carbon-intensive fuel available for energy generation — can still be burned without increasing greenhouse gas emissions.

UKAEA’s Llewellyn Smith identified CCS as the biggest technological challenge facing the energy sector over the next 10 years: ‘There remain technical and economic issues, although the latter look most important,’ he said.

Adrian Bull, Westinghouse’s UK stakeholder manager, hopes most fossil fuel power plants will be equipped with CCS by mid-century. ‘Certainly any new plants being built should have this incorporated,’ he said. ‘If CCS hasn’t by then been shown to be technically and commercially viable on the necessary scale, then I’d be surprised — and disappointed — to see new fossil-fuelled plants being built [in the UK].’

The UK energy mix

In the shorter term, there was little consensus over the contributions that energy generation technologies will make to UK power supply.

Jan Matthiesen, head of onshore for the British Wind Energy Association, predicted that by 2020, renewables could provide 40 per cent of UK power.

Stephen Salter of Edinburgh University’s Institute for Energy Systems, who is widely regarded as the father of wave power, was less optimistic. ‘At the present rate of progress I cannot see the renewables making the contribution that would have been technically possible, and so the 2020 change will be in the direction of more oil and gas,’ he said.

The UK Energy Research Centre’s Skea does not believe in ‘favourable mixes’, and said he’d be happy with whatever mixture results from public policy aiming at restricting carbon emissions. ‘I think that renewables will advance as fast as the planning system and grid connection permit; gas will make the biggest contribution to new capacity; and the power companies will invest in some new coal to create a more diverse mix.’ He added: ‘Nuclear is the big unknown and if it does go ahead there could be a couple of stations by 2020, displacing mainly gas.’

Experts from the nuclear sector were guarded. Within the next 10-15 years, said Robin Grimes, professor of materials physics at Imperial College and one of the leaders of the Keeping Nuclear Options Open programme, the Advanced Gas-Cooled Reactors that make up the bulk of the UK’s nuclear fleet ‘may have a difficult time with their safety cases,’ which means new gas-fired generators are inevitable.

The timescale is short for new nuclear, he said: ‘In just 10 years time new nuclear build could only just be making an impact,’ he said.

Dalton Nuclear Institute’s Howarth said the first new nuclear plants ‘will hopefully be connected to the grid,’ by 2020.

And Westinghouse’s Bull said even with lifetime extensions for the existing nuclear fleet and two or three new stations, nuclear ‘will struggle to get above the 20 per cent of power supply which it meets at present.’

Bull had the pithiest answer to the question of where we’ll be by 2020: ‘It’s a shame we have to start from where we are!’

William Nuttall, senior technology policy lecturer at Cambridge University’s Judge Business School and one of the brains behind the ‘fusion island’ fusion power-to-hydrogen concept, is more optimistic for nuclear and renewables.

Balancing the demands of keeping the electricity price reasonable for the public, minimising environmental impact, and ensuring security of supply, he predicted a 35 per cent contribution for gas turbines, 25 percent for nuclear, 20 per cent for desulphurised coal, and 20 per cent for renewables, mostly via wind generation. ‘Furthermore,’ he added, ‘it seems probable that our competitive generation market can be incentivised by policy to deliver such a mix.’

The role of policy

Our experts had some interesting suggestions on how the government could help cut the UK energy sector’s carbon footprint. Nuttall said demand-side management would be the most effective measure, with a widespread roll-out of smart metering for electricity and gas to aid both domestic and industrial energy conservation.

Bull looked to legislation to restrict emissions. ‘I think a firm commitment to ensure that the European Emissions Trading Scheme, or a UK equivalent, will be in place for decades to come,’ he said. ‘Longer term, I see personal carbon allowances as being the catalyst to all sorts of innovation to allow people to make much more informed choices about their own carbon footprint and alter their behaviours accordingly.’

Setting and enforcing a carbon price was a popular option. Pierre-Jean Lahourcade, energy efficiency manager for EDF Energy, advocated a ‘rise in the cost of carbon to reflect the cost of climate change impact on our economies.’ Llewellyn Smith said a ‘strong market signal of a future carbon price’ could lead to a side benefit, with some of the funds raised being ploughed back into energy R&D.

Neil Kermode, director of the European Marine Energy Centre in Orkney, also said energy tariffs were important. ‘Allocate everybody a basic level of energy at a subsidised level but put in place an increasing tariff for energy used above that,’ he said. Savings below that level would be tradeable. ‘There would remain the freedom to choose energy use patterns in the full knowledge that profligate use would be expensive and energy thrift would be rewarded.’

Skea, meanwhile, said what was needed was not so much new initiatives as a commitment to implement ‘the many ideas already on the table’, with ‘a strong post-Kyoto international climate agreement and demanding carbon reductions under future phases of the EU Emissions Trading Scheme’.

One area where government will play a role is the construction of new nuclear plants, and our experts differed on how this should be approached. Skea said the biggest obstacle was the investment climate; nuclear is too high-risk, he believes. ‘The UK’s liberalised power markets, coupled with uncertainty about future carbon prices, does not make a comfortable market for any capital-intensive, low-carbon technology,’ he said.

Imperial’s Grimes thinks the planning process will delay new build. ‘At present, the various processes tend to proceed in sequence rather than in parallel,’ he said. ‘Furthermore, the planning process can be taken advantage of by politically motivated environmental organisations, regardless of the majority views of the local population.’

Only in the UK is the private sector expected to absorb the whole financial risk of building these ‘enormously expensive capital projects’, he said.

Howarth, meanwhile, is more concerned with the technology. ‘Ensuring the regulator has the necessary resources and capability to assess the designs is a fine line between taking credit for systems already licensed overseas but also showing the UK undertakes a rigorous and independent assessment,’ he said. However, he added, demanding bespoke solutions for the UK is a dead end, as vendors can easily sell their designs in the US and Asia and the UK would therefore get left behind.

Nuttall has a more political viewpoint on nuclear. A decision is needed soon, he said, but the next general election, likely to be close, could be in 2009 or 2010. ‘History suggests a Labour-Liberal Democrat coalition,’ he said. If the Lib-Dems were to get the energy and environment portfolio, they ‘might be able to deliver a clear victory to their supporters by ending plans for new nuclear build’.

Looking to the future

Asked to predict which technologies will be keeping the lights on by 2050, our experts said fusion and marine renewables are the wild cards for energy generation. Howarth said fusion ‘is effectively the Lottery ticket’, and ‘it is worth conducting the research now and building demo systems to assess whether it is viable or not’.

Grimes said mid-century was ‘probably too soon’ for fusion but added: ‘It may be that our ability to harness energy from renewables is sufficiently advanced that the cost of fusion becomes largely prohibited.’ He said conventional nuclear designs based on passive safety systems ‘will certainly dominate’, but concerns over the abundance of uranium could see a switch to thorium-fuelled reactors.

Skea believes fusion ‘will almost certainly have advanced in a number of countries, but others will have rejected it,’ and both the hydrogen economy and nuclear fusion are beset by scientific and economic uncertainty.

In the shorter term, wind is a plausible option for expansion, but he sees great potential in thin-film solar photovoltaics, which have huge global potential in the long term.

‘Marine technologies are somewhere in the middle,’ he said. ‘Bio-energy may be the most complex issue. Development is linked to land use, wider environmental change, agricultural policies and the need to feed the world.’

Sidebar: The fourth revolution

In his recent speech on the environment, Gordon Brown said combating climate change ‘will require nothing less than a fourth industrial revolution’.

The challenge of decarbonising energy was equivalent to the development of the steam engine, the internal combustion engine, or the microprocessor, he said. ‘This represents a huge challenge to the UK, but also an opportunity.’

From our coverage this year, and judging from the opinions of our experts, the tools to tackle the challenge are all there. We have a daunting task ahead.