Saturday, July 1, 2017

US '100% renewable by 2050' scenario 'unreliable'

In 2015, Stanford University Prof. Mark Jacobson and his colleagues, in a paper in the Proceedings of the National Academy of Sciences, argued that between 2050 and 2055, the United States could be entirely powered by ‘clean’ energy sources (wind, solar and water power) and ‘no natural gas, biofuels, nuclear power, or stationary batteries are needed.’ http://www.pnas.org/content/112/49/15060
However, a group of 21 researchers have now published a study in the same journal arguing that the work ‘used invalid modeling tools, contained modeling errors, and made implausible and inadequately supported assumptions’.
They say that ‘The study’s numerous shortcomings and errors render it unreliable as a guide about the likely cost, technical reliability, or feasibility of a 100% wind, solar, and hydroelectric power system. It is one thing to explore the potential use of technologies in a clearly caveated hypothetical analysis; it is quite another to claim that a model using these technologies at an unprecedented scale conclusively shows the feasibility and reliability of the modeled energy system implemented by midcentury.’
Crucially they say it ‘does not provide credible evidence for rejecting the conclusions of previous analyses that point to the benefits of considering a broad portfolio of energy system options. A policy prescription that overpromises on the benefits of relying on a narrower portfolio of technologies options could be counterproductive, seriously impeding the move to a cost-effective decarbonized energy system’. http://www.pnas.org/content/early/2017/06/16/1610381114.short?rss=1
The authors of the critique include Dr Ken Caldeira, who, in 2103, along with others, famously wrote an open letter to environmentalist asking them to back nuclear power- an option Jacobson et al treat with distain. The authors of the critique say that the inclusion of nuclear and CCS, as well as biomass/BECCS (which Jacobson et al also avoid), alongside renewables, would allow US power to be 80% carbon free. Jacobson has replied to the critique which he says is ‘demonstrably false’ and ‘riddled with errors’ e.g. nuclear & CCS wouldn’t help balance variable renewables and would push up costs. He also sees it as too focused on carbon saving. His approach was broader, e.g. also looking at air pollution health impacts, energy security and nuclear risks: http://www.ecowatch.com/pnas-jacobson-renewable-energy-2444465393.html  and  http://www.pnas.org/content/early/2017/06/16/1708069114.extract
The debate continues: http://www.washingtonpost.com/news/energy-environment/wp/2017/06/19/a-bitter-scientific-debate-just-erupted-over-the-future-of-the-u-s-electric-grid/ and http://www.nytimes.com/2017/06/20/business/energy-environment/renewable-energy-national-academy-matt-jacobson.html  It is not just an academic debate; it touches key strategic issues for the US and the rest of us. Jacobson’s team had also earlier developed a global version, published in Energy Policy, and more recently, with a team of 27 or so, has been working on an upgraded version covering 139 countries in detail, with variable supply and demand balancing carefully addressed : http://web.stanford.edu/group/efmh/jacobson/Articles/I/CountriesWWS.pdf These 100% scenarios suggest that there is no need for nuclear or carbon storage fixes- there are sufficient renewables of various types to supply all global energy needs - and soon. Given that Jacobson excludes (most) biomass, that is certainly provocative. Most other ‘high renewables’ global and national scenarios include biomass and many of them only look to 80-90% renewable electricity contributions by 2050.  However, Jacobson’s work and some of the other earlier studies like that by WWF, in effect set the benchmark high and the studies that have followed do seem to be gradually filling out the expectations. For example, in a joint report with the IEA, which says ‘near 70%’ may be possible, IRENA looks to renewables supplying 82% of global electricity by 2050:  http://www.irena.org/menu/index.aspx?mnu=Subcat&PriMenuID=36&CatID=141&SubcatID=3828
Indeed, some have now gone even further.  Lappeenranta University of Technology (LUT) in Finland, has produced very ambitious EU and NE Asian studies of renewable potentials, with hourly balancing and supergrid links: http://www.researchgate.net/publication/313403782_A_low-cost_Power_System_for_Europe_based_on_Renewable_Electricity  and  http://www.researchgate.net/publication/280098413_North-East_Asian_Super_Grid_Renewable_energy_mix_and_economics
And it says 100% of power by 2030 globally is technically viable and affordable. https://eandt.theiet.org/content/articles/2016/11/global-energy-model-solely-reliant-on-renewables-realistically-simulated/
100% by 2030 would certainly be pushing it!  And their analysis has attracted some criticism- see the initial links to the critiques by Energy Matters in this riposte from LUT: http://euanmearns.com/the-lappeenranta-renewable-energy-model-is-it-realistic-lappeenranta-responds/          
The detailed technical debate over whether the numbers add up or not will no doubt continue, and is valuable, but to some extent it misses the strategic point.  What has been achieved is that the debate is no longer couched in terms of whether renewable can make contribution or not, but on the scale of that contribution. Now we are debating whether it will or should be near 70% of global power (IEA) or above 80% (IRENA) by 2050. Or even more.
Time was when it was common for renewables to be almost totally dismissed and trivial, irrelevant and foolish. Even now we are treated to the selected use of data to minimise their significance. Thus the new BP World Energy Outlook says renewables, excluding hydro, only supplied under 4% of energy globally in 2016. That figure is for primary energy, which BP calculates in terms of the tonnes of oil that would have be burnt in a power plant to give the same energy output, even if it’s actually wind or solar generated energy being used. So, for comparisons sake, they say the raw plant output data is ‘converted on the basis of thermal equivalence assuming 38% conversion efficiency in a modern thermal power station’. http://www.bp.com/content/dam/bp/en/corporate/pdf/energy-economics/statistical-review-2017/bp-statistical-review-of-world-energy-2017-full-report.pdf
However, that’s an unfair comparison: unlike fossil or nuclear-fired steam-raising plants, wind and solar plants don’t suffer from 62% thermodynamic energy conversion losses. It’s also not a very useful comparison- what matters for these systems is the energy delivered to users. On that basis, REN 21 calculates that renewables, excluding hydro, accounted for around 6.6% of final energy uses in 2015, or 19.3% including hydro. While nuclear comes out at 2.3%: http://www.ren21.net/gsr-2017/
You can play with the figures in other ways too.  REN21 says that renewables, including hydro, supplied 24.5% of global electricity in 2016, with wind supplying 4%. But reverting to the use of primary energy, Matt Ridley manages to render the wind statistic as in effect zero, ‘to the nearest whole number’, since the IEA say it was 0.46% of total energy in 2014!  
Leaving these tiresome number games aside, there are some more important issues. Renewables like wind and solar deliver variable outputs, so that has to be taken into account. Sadly, that too can lead to some confusion, willful or otherwise. Those hostile to renewables sometimes say the backup needed will be prohibitively expensive. But the most recent analysis has put the extra cost at around 10% for moderate renewable contributions. And that ignores the possible cash and health cost savings from not using fossil fuel. As IRENA has commented reducing the impact on human health and mitigating climate change would save between two- and six- times more than the costs of decarbonisation’. http://www.irena.org/menu/index.aspx?mnu=Subcat&PriMenuID=36&CatID=141&SubcatID=3828

Scenarios are helpful to harden up estimates like that, but the overall direction of travel should be clear- with renewables playing a central role.  Within that there are choices to be made- do we include biomass. Large hydro? Do we focus on small scale systems or accept some large systems?  Scenarios can help assess the likely energy system impacts of these and other options, and may also be used to identify the scale of any wider impacts, but in the end it’s a matter of strategic choice based on assessments of likely costs and benefits, risks and obstacles. A system based on a wide range of renewables of various scales and types seems likely to be more robust and sustainable than one based mainly on large probably costly and possibly inflexible nuclear plants coupled perhaps with CCS as a fix for continued interim fossil fuel use, and it may be possible to model that to see if it is true. But in reality, while scenarios and debates over them can help, if done without too much rancor, we still have to make decisions based on future outcomes which can’t be fully modeled.  

Thursday, June 1, 2017

Election Time: Green energy promises

In its election manifesto, Labour says it will ‘ensure that 60 per cent of the UK’s energy comes from zero-carbon or renewable sources by 2030’. That’s in line with the scenario it produced last year, which talked of getting 65% of UK electricity from renewables by 2030, with 47GW of offshore wind, 21GW of onshore wind (up from around 5GW and 10GW at present respectively) and 25GW of PV solar (up from 12GW now): http://blog.environmentalresearchweb.org/2016/10/08/labours-65-renewables-by-2030-plan/ In parallel, Labour had shown strong interest in the various green gas options for heating: http://blog.environmentalresearchweb.org/2016/09/03/labours-green-gas-push/

60% of all energy (if that’s what they really meant) is however a significant goal, even if maybe 10% would come from existing and planned nuclear, which presumably it sees as being included in the ‘zero carbon’ category- although in reality, given the energy and carbon debt associated with fissile fuel production, it isn’t actually zero carbon.

However, the commitment to nuclear (and to Euratom!), although there, is a little fudged.  While the Manifesto says nuclear will continue to be part of the energy supply’, and that we will support further nuclear projects and protect nuclear workers’ jobs and pensions,’ it goes on: ‘There are considerable opportunities for nuclear power and decommissioning both internationally and domestically.’ Is the implication that this is where the job security for nuclear workers will be found- not in new nuclear generation? It seems not since, separately,  Jeremy Corbyn said that ‘Labour supports nuclear power as an important part of a low carbon energy mix and would continue to support the construction of Hinkley C’: www.ecns.cn/2017/05-22/258487.shtml and it also backed Wylfa in Wales: www.walesonline.co.uk/news/politics/labour-pledges-support-new-nuclear-13068863

As for other energy workers, it notes that ‘The low-carbon economy is one of the UK’s fastest-growing sectors, creating jobs and providing investment across each region. It employed an estimated 447,000 employees in the UK in 2015 and saw over £77 billion in turnover. With backing from a Labour government, these sectors can secure crucial shares of global export markets’. The 447,000 figure seems to include nuclear workers, but recent ONS data put nuclear related employment at just 5.3% of total UK low carbon energy employment, compared to around 20% in renewables, most of the rest being in energy efficiency: www.ons.gov.uk/economy/environmentalaccounts/bulletins/finalestimates/2015results

In terms of fossil energy, Labour says it will ‘ban fracking because it would lock us into an energy infrastructure based on fossil fuels, long after the point in 2030 when the Committee on Climate Change says gas in the UK must sharply decline’, but it will support emerging technologies such as carbon capture and storage, since they can ‘help to smooth the transition to cleaner fuels and to protect existing jobs as part of the future energy mix’.
However, this transition does not seem to be total:  it promises to ‘safeguard the offshore oil and gas industry, we will provide a strategy focused on protecting vital North Sea assets, and the jobs and skills that depend on them.’  Although it does add ‘We are committed to renewable energy projects, including tidal lagoons, which can help create manufacturing and energy jobs as well as contributing to climate- change commitments’.
Maybe it is suggesting that this is where some offshore workers will be redeployed in time – though it could also have highlighted offshore wind and tidal stream and wave projects as possible destination.
There will also be a lot of employment in energy efficiency in all sectors e.g. Labour says it will ‘insulate four million homes as an infrastructure priority to help those who suffer in cold homes each winter. This will cut emissions, improve health, save on bills, and reduce fuel poverty and winter deaths’.
Social and economic issues are clearly to the fore, with plans for radical changes in the management and structure of the energy system.  Labour says it will seek to ‘regain control of energy supply networks through the alteration of operator license conditions, and transition to a publicly owned, decentralised energy system’.  Specifically, it looks to ‘the creation of publicly owned, locally accountable energy companies and co-operatives to rival existing private energy suppliers, with at least one if every region, and to ‘legislating to permit publicly owned local companies to purchase the regional grid infrastructure, and to ensure that national and regional grid infrastructure is brought into public ownership over time. With an emergency price cap in the meantime.
Overall then, nuclear apart, a quite radical programme, funded, along with the rest of its £48.6bn programme, mainly by increased taxation on the 5% of the highest earners and by raised corporation tax: www.labour.org.uk/index.php/manifesto2017
Its interesting to compare it with the Green Party manifesto. That says ‘We will ensure that all new investment in energy is directed towards clean, renewable energy, and a smarter, networked grid, with battery-storage, demand-side measures, and interconnection. We will introduce a ban on fracking, phase-out the £6bn-a-year fossil fuel subsidies, bring forward the coal phase-out date to 2023 (at the latest), divest public funds from the fossil fuel industry, and ensure a just transition for those communities dependent on fossil fuel jobs. We will cancel the contracts for Hinkley Point C (saving £37bn), and scrap plans for all new nuclear power stations, instead investing in renewable energy, a flexible grid, and interconnection to Europe’.
So some similarities, but no fudges on nuclear or fossil fuel, and a strong commitment to specific renewables. It will ‘end the effective ban on-onshore wind– the cheapest form of new electricity generation– and introducing new support for onshore wind and solar-photovoltaics; scaling up investment in offshore wind and marine renewables; significant investment in vehicle electrification and charging infrastructure; and a comprehensive plan to decarbonize heat, including pilot residential and commercial projects’. There will also be a national programme of insulation and retrofitting to make every home warm – bringing two million people out of fuel poverty, insulating nine million homes, and creating hundreds of thousands of jobs’. So a bigger scheme than Labour’s.
In terms of structural changes, it will end the monopoly of the Big Six by building democratic, locally owned alternatives - reaching at least 42 gigawatts by 2025. We will require grid operators to give priority access to community energy projects, and pioneer a new Community Energy Tool Kit to empower local communities to create energy and municipal heating projects in every town and city’.
All very different from UKIP- which backs nuclear and fracking and wants to repeal the Climate Change Act and exit the Paris climate accord! www.ukip.org/manifesto2017
The Conservatives, being the sitting tenants, had the advantage of being able to point to the programme they had backed, with renewables now at 34GW- supplying 25% of UK power. But that was much reliant on the Lib Dems in the coalition earlier – and the Lib Dems clearly now want to continue with more: 60% of electricity by 2030. Like Labour, they oppose fracking and back nuclear - though it has to be unsubsidised. Which seems impossible! www.libdems.org.uk/environment
But that doesn’t seem to worry the Tories, although excessive energy costs have ostensibly been the reason for the cuts in support for renewables, although their proposed price cap on energy got mixed reactions: www.telegraph.co.uk/news/2017/05/08/unfair-energy-companies-raise-prices-37pc-theresa-may-can-bring/ and www.theguardian.com/business/2017/may/14/tory-price-caps-wouldnt-need-cut-energy-efficiency-schemes Also: www.bbc.co.uk/news/business-39858948 It’s manifesto softened this commitment and promised a review of energy costs, but with fracking backed and onshore wind still opposed: www.conservatives.com/manifesto.
Meantime, while the Big 6 energy utilities dug in against the proposed price cap, independent Pure Planet offered a new allegedly100% low-cost renewable deal, in effect sidestepping them and the cap: https://purepla.net/ The Sun liked it! www.thesun.co.uk/money/3515054/new-challenger-energy-firm-launches-promising-to-undercut-the-big-six-by-20/ The existing independents,  Ecotricity and Good Energy, charge more, although they invest in new capacity. But one way or another, maybe this is what might emerge under the more open schemes proposed by Labour, the Lib Dems and the Greens. Though will they get the chance? Or will only the SNP be able to push their radical plans- which includes a 1GW target for community and locally-owned energy by 2020, and 2 GW by 2030, within their overall ‘50% renewable energy by 2030’ draft plan for Scotland. www.gov.scot/Resource/0051/00513466.pdf
*Interestingly, the Tory Manifesto ignored nuclear. That led to this speculative piece: http://www.theecologist.org/News/news_analysis/2988965/conservative_election_manifesto_signals_the_end_of_new_nuclear_power.html



Monday, May 1, 2017

Back to the future: old nukes for new

In 1965, Fred Lee, the UK’s then Minister of Power, famously told the House of Commons that 'we have hit the jackpot this time,' with the Advanced Gas-cooled Reactor (AGR). That was maybe a reference back to an earlier episode, when expansive claims were made that the ZETA nuclear fusion test plant heralded a global breakthrough- it didn’t.   Unfortunately, things also went very wrong as the AGR programme unfolded. The first station, on the south Kent coast, was Dungeness B. It was ordered in 1965, but did not start up until 1982, over 17 years later, by which time its cost had reached more than five times the initial estimate, and its output had been scaled down by over 20%. In 1985, two decades after the original order, the second reactor at the station had only just started up. Atomic Power Constructions, the company that won the Dungeness B contract in 1965, had by 1970 collapsed in total technical, managerial and financial disarray:
Project disasters like that might be seen as part of the learning process, though the UK seems hell bent on a repeat, with EDF’s £24bn Hinkley EPR project, to be followed perhaps by more, with a variety of new ‘first of kind’ reactors projects being proposed. As Peter Atherton put it in evidence to a Lords committee: we will be building four different reactor types, with at least five different manufacturers, simultaneously. That is industrial insanity’.  
While some nuclear enthusiasts hope that these Generation III reactors, like the EPR or its rivals, will be successful, there is also pressure to move on to new technology and so called Generation IV options, including liquid sodium-cooled fast neutron breeder reactors, helium-cooled high tempertutre reactors and thorium-fuelled molten salt reactors, at various scales.  As I describe in my new book Nuclear Power: Past, Present and Future, many of them are in fact old ideas that were looked at in the early days and mostly abandoned. There were certainly problems with some of these early experimental reactors, some of them quite dramatic. Examples include the fire at the Simi Valley Sodium Reactor in 1959, and the explosion at the 3MW experimental SL-1 reactor at the US National Reactor Testing Site in Idaho in 1961, which killed three operators. Better known perhaps was and the core melt down of the Fermi Breeder reactor near Detroit in 1966. Sodium fires have been a major problem with many of the subsequent fast neutron  reactor projects around the world, for example in France, Japan and Russia.
For good or ill, ideas like this are back on the agenda, albeit in revised forms. That includes  the currently much promoted idea of scaling down to small modular reactors- SMRs. In theory they can be mass produced, so cutting costs. Not everyone is convinced:  scaling down doesn’t necessarily reduce complexity and it’s that that may be the main cost driver.  One cost offsetting option is to locate them in or near cities so that the waste heat they produce can feed into district heating networks. But given the safety and security risks, will anyone accept them in their backyard? And like all nuclear plants, they will produce dangerous long lived wastes that have to be dealt with.
Fast neutron breeder reactors can produce new plutonium fuel from otherwise unused uranium 238 and may also be able to burn up some wastes, as in the Integral Fast Reactor concept and also the Traveling Wave Reactor variant. Molten Salt Reactors using thorium may be able to do this without producing plutonium or using liquid metals for cooling. Both approaches are being promoted, but both have problems, as was found in the early days. Certainly fast breeder reactors were subsequently mostly sidelined as expensive and unreliable. And as heightening nuclear weapons proliferation risks. The US gave up on them in the 1970s, France and the UK in the 1990s. Japan soldiered on, but has now abandoned its troubled Monju plant. For the moment it’s mainly Russia that has continued, including with a molten lead cooled reactor, although India also has a fast reactor programme, linked to its thorium reactors plans.
Thorium was used as a fuel for some reactors in some early experiments and is now being promoted again- there is more of it available globally than uranium. But there are problems.  It isn’t fissile, but neutrons, fast or slow, provided by uranium 235 or plutonium fission, can convert Thorium 232 into fissile U233. However, on the way to that, a very radioactive isotope, U232, is produced, which makes working with the fuel hard. Another isotope, U234 is also produced by neutron absorption. Ideally, to maximise U233 production, that should be avoided, but experts are apparently divided on whether this can be done effectively.
The use of molten salts may help with some of these problems, perhaps making it easier to play with the nuclear chemistry and tap off unwanted by-products, but it is far from proven technically or economically. The economics is certainly challenging. Nuclear plants of any sort may not be competitive in the emerging electricity market, as renewables get ever cheaper and their market share expands, but some nuclear options might be able to compete in the heat and synfuel markets. However, even that is unclear- renewables may also be able to compete in meeting these end uses, with fewer side effects.   
Back in the 1950s, President Eisenhower launched Atoms for Peace initiative, promising US aid with the world-wide development of bountiful nuclear energy, and that idea has lingered on. In 2006, under the Global Nuclear Energy Partnership (GNEP) backed by President George W Bush, US Energy Secretary Samuel Bodman said that ‘GNEP brings the promise of virtually limitless energy to emerging economies around the globe’. After Fukushima and the economic challenges to nuclear presented by gas and renewables, GNEP was in effect abandoned and we don’t hear rhetoric like that so much: nuclear is on the defensive, only supplying 11% of global electricity as against 25% from renewables, with the cost of the later falling rapidly, while nuclear costs seem to be rising inexorable. Whether the new Generation of fission technologies will be able to resuscitate it remains to be seen.  It doesn’t seem a good bet: http://science.sciencemag.org/content/354/6316/1112.1  And if you still have hopes for fusion, see this: http://thebulletin.org/fusion-reactors-not-what-they’re-cracked-be10699
All this and more is covered in my new IOPP  book ‘Nuclear Power: Past, Present and Future’: http://iopscience.iop.org/book/978-1-6817-4505-3
*If you are a real devotee of nuclear history, take a look at this new long, partisan and somewhat overwhelmingly chaotic video selling thorium molten salt reactors: https://www.youtube.com/watch?v=H6mhw-CNxaE