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January 2013 Archives

Energy saving

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A DECC report last year 'Capturing the full electricity efficiency potential of the UK' identified a potential for cutting energy demand by 40% by 2030, 155 TWh in all, of which current policy is estimated to capture ~54 TWh (~35% of total potential). They focused on three key sectors, and in each case they looked at the 3 largest categories of abatement measures per sector, which together are estimated to deliver ~127 TWh of savings (~80% of total potential):

Residential: The top 3 measures' saving potential is ~58 TWh: CFL lighting, appliances and better insulation, of which ~75% is expected to be captured by current planned policies (primarily Products Policy)

Services: The top 3 measures' saving potential is~45 TWh: better insulation, lighting controls & HVAC, of which ~15% should be captured by current/planned policies

Industrial: The top 3 measures' saving potential is ~24 TWh: pump, motor and boiler optimisation, of which ~5% is expected to be captured via current/planned policies

In 2020, the abatement potential is estimated at ~115 TWh of which ~60% should be captured by current policy.

Subsequently DECC produced a new energy efficiency strategy. It was couched in quite general terms. It outlines the existing energy saving programmes, including the Green Deal, and proposes some possible new developments and areas for study, aiming to 'strengthen the evidence base.' But there are no new major policy commitments.

There is no question that it is hard to be sure which areas of intervention are most cost effective, and that making effective savings in some areas is problematic- e.g. in solid wall housing. There is also the problem that once the easy and cheap savings have been made it costs more to make further savings- and commitment can falter. The DECC Strategy report warns that 'The impact of current policies that reduce energy demand are assumed to taper off in impact after 2022, (the fourth carbon budget period) and by 2030 the share of energy efficiency policy impact falls to 31%.'

However, it does look at ways to do better. It suggests that larger savings could possible if projects were funded on the basis of a social discount rate i.e reflecting social and environmental criteria and well as conventional economic criteria. It estimates that 'through socially cost-effective investment in energy efficiency we could be saving 196TWh in 2020, equivalent to 22 power stations', with the potential after that being even greater.

The wider social criteria certainly come to the fore in the domestic sector- depending on how it is done. Consumer Focus says that investing money raised through carbon taxes in a major energy efficiency programme could cut household energy consumption by 5.4% by 2027 and overall carbon emissions by 1.1%, while creating 130,000 jobs and reducing fuel poverty.

However not everyone likes carbon taxes- they are a blunt instrument and hit the energy poor hardest, even if the resultant energy saving may also benefit them longer term. A report published by Green Alliance and WWF-UK argues for an energy efficiency Feed In Tariff to create a 'market' for 'negawatts' (saved energy) allowing new and existing companies to compete with each other to find innovative ways to help consumers across the economy save electricity.

Drawing on international experience the report demonstrates how the UK can learn from energy demand reduction programmes abroad; schemes in the USA show that it is much cheaper to reduce demand when compared with building new supply. For example, replacing inefficient appliances with new efficient ones costs on average £33/megawatt hour (MWh) compared with the cheapest low carbon supply costing £83/MWh.

The report said that the EE FiT would complement other energy saving policies such as product labeling and, if designed appropriately, the EE FiT would also have the potential to work well with the Green Deal, thus maximising energy savings from homes.

Green Alliance/WWF: Creating a market for electricity savings: Paying for energy efficiency through the Energy Bill Rachel Cary and Dustin Benton, Oct 2012: http://assets.

Sadly the Electricity Market Reforms do no address energy efficiency, a point noted by the Economist:

However, in parallel with the EMR, DECC launched a new consultation on energy efficiency, looking at possible way to stimulate uptake of energy efficiency measures in all sectors, including the idea of Feed In Tariff for energy saved via investment in efficiency as proposed by WWF/the Green Alliance. In addition, the EMR did include a new Capacity Market for ensuring balanced and secure energy provision, and it is possible that energy saving measures could be eligible for long term contracts, alongside low carbon supply project, within that.

We certainly do need a more effective approach: so far the much touted Green Deal commercial loan system seems to be something of a damp squib, barley touching the huge potential. We really ought to do better. The report 'Less is More: Energy Security after Oil', published by AECB- the sustainable building association- pointed out that investment in energy efficiency can result in major energy reductions for the least cost, and remove the need for expensive investment in new generating infrastructure. According to the report's principal author, AECB's energy expert David Olivier, 'Energy efficiency remains as important an opportunity for us as the discovery of a new series of giant oilfields, but without their global warming impact. Many energy efficiency measures save energy worth more than the cost of the measure, so not only do they pay us to save energy, we also save CO2 at a profit.'

AECB CEO Andrew Simmonds said. "Efficiency really is the gift that keeps on giving. Efficient use of energy saves on bills now. And it saves the capital cost of all the new extraction, generation and transmission technology that our current levels of energy consumption will demand in the future. We can stick to the cheaper, safer options for new energy, and do without the riskier, pricier ones. None of the energy efficiency measures cited in our report would cost the UK more than about 3p per kWh electricity saved. Who wouldn't want electricity at 3 p/kWh, when most consumers currently pay 8-13 p/kWh?"

May be can do better. For an interesting study on energy saving options in housing, focusing on Europe, Japan, and the USA, see the International Council of Chemical Associations 'Building Technology Roadmap', which claims by 2050 'tighter new building standards combined with a more ambitious renovation rate could result in a 23% reduction in energy use and GHG compared to 2000', rising to 41% if energy supplies are decarbonised, with net emissions falling by about 70%.

*As I've noted before, there is also a lot of potential for energy and cash savings in the industrial sector.

Which would you prefer to live near- a nuclear plant or a wind farm?

For many people, nuclear plants are threatening. However some say this fear is misplaced. In an article on the impacts of Fukushima nuclear accident, Steve Kidd form the World Nuclear Association noted that ' there have so far been no radiation-induced deaths, nor are there likely to be any in the future' and asked 'how can this relatively benign incident create such a degree of fear that it is dominating discussion of nuclear power's future?'

He says, by way of explanation, that it is at least in part due to mistaken beliefs about the impacts of radiation. And more specifically he says: 'There is undoubtedly a huge economic impact of moving people from their homes and jobs in order to protect them, but the reason for this is the essentially unwarranted fear of radiation. This in itself can cause many illnesses, providing much wider implications a long way from the scene of the accident.'

You could of course ask what would have happened if they had not been moved, but the more general point is that stress and worry can be killers. Kidd comes perilously close to claiming that the main culprit is what he labeled the 'anti-nuclear brigade'. For them, he says, 'the misunderstanding of radiation is an important key to discrediting nuclear power,' thereby raising unwarranted fears. 'Yet they are the very people who are inducing such effects by continuing to feed the public scares about radiation! So the psychological impacts become essentially self-fulfilling; they stoke up an (illusory) fear and then complain about the consequences of this.'

No one disputes that radiation exposure can be a killer, but it is interesting that the same sort of interaction between fear and impacts may also be occurring in relation to wind turbines- which are usually seen as pretty benign in terms of heath impact. Wind projects have been around for 20 years or more, but recently noise issues have emerged, with anti-wind groups claiming that (inaudible) low frequency infra sound can lead to significant health problems. The media has taken up this issue, with some claiming that thousands of people are being affected adversely. See for example: and :

As I have reported before, the validity of some of the data, and of the analysis if it, has been disputed, given its reliance on small samples and the use of anecdotal evidence : and See also.

The official view remains that there are no significant health impacts from wind farm noise, but, to avoid nuisance, there are limits and separation rules imposed. Certainly in terms of audible sound from gearing and aerodynamic swish, although some earlier models were more noisy, gear train noise has been drastically reduced and aerodynamic noise is usually very low with modern wind turbines, though it can still be annoying to some, as can the rumble of a fridge or nearby road noise. But it is possible that some people are more sensitive, especially to (inaudible) low frequency infra sound. More subtly, it has been argued that the 'wind turbine syndrome', as its now been labeled, is a 'communicatable disease', spread by exposure to anti-wind propaganda, and/or only affecting people who don't like wind farms. For example Simon Chapman, a professor of public health at the University of Sydney, says that studies have concluded that "pre-existing negative attitudes to wind farms are generally stronger predictors of annoyance than residential distance to the turbines or recorded levels of noise." See

The debate continues, sometimes becoming quite heated, with local (and national) anti-wind campaigners digging in hard, conflating a range of concerns and arguments. However some are more balanced; see this video which makes a reasonable, non-hectoring, case for greater separation from residences, on noise and shadow/flicker effect grounds:

Wind developers are sometimes defensive on these issues, but for a balanced view see

It is conceivable, although unlikely, that some newer larger machines generate more infra sound, or have been poorly sited, but even if they are blameless in this regard, sensible spacings from residential locations seem wise, on the basis of the precautionary principle.

In addition, local ownership might help. It seems pretty clear than if you are part of a community co-op that owns the project and benefits from it financially, then you will find it far less offensive. For example, in Denmark, where most wind projects are locally owned, the old Danish proverb 'your own pigs don't smell' seems to hold sway. It's similar in Germany: many projects are locally owned and in both countries, unlike in the UK, opposition to wind power is relatively rare.

The UK Science and Technology Select Committee's s report on 'Energy Risks and the Public' said that they ' were impressed by a citizen partnership model being developed in Germany for wind farms and suggest that enabling communities to feel more ownership of local energy infrastructure by offering shares in projects could be conducive to building trust and acceptance. Partnership models could form part of community benefits discussions for new nuclear build and other energy infrastructure.'

Somehow though I don't see local community-owned nuclear power stations emerging any time soon, although some communities may be offered incentives to accept nuclear facilities near them. But personally, regardless of any cash incentive, if I was given a choice, I would rather live a mile from a wind farm than 30 miles from a nuclear plant. And that seems to be a quite widespread view, with, in an ICM/Guardian survey in 2012, 60% of those asked being happy to have wind energy projects near them, while 72% opposed having a nuclear plant in their area.

For more on the debate on wind noise, see:

A barrage too far?

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The proposal for a privately funded tidal barrage across the Severn Estuary continues to attract media attention. Last year Peter Hain, former shadow Welsh Secretary, who is backing the idea, had a meeting with David Cameron which he says was a 'more productive than might have been expected'. Lord Heseltine also included the Barrage as one of the large infrastructure projects he proposed in his recent report to government. The Energy and Climate Change Select Committee has also been looking at it again.

The new barrage proposal is being led by engineering consortium Corlan Hafren, backed by Halcrow, Arup, and Mott MacDonald, and it is claimed that a number of sovereign wealth funds (e.g. Qatar) might provide finance- all in, around £30bn could be needed.

Previous plans for a Barrage by the Severn Tidal Power Group (STPG) were seen as much too expensive and too environmentally damaging: most environmental and wildlife groups like RSPB were strongly opposed and in 2010 the government decided against supporting it as a public project. But it left the door open to private developers. Hafren's plans involve installing a larger number of larger diameter slower rotation speed low-head turbines, each with a 9-meter (30 foot) diameter, 1,064 in all, mounted in a barrage 11 miles between Lavernock Point on the South Wales coast and Brean in Somerset.

The power station element of the project would, it's claimed, cost about £25 billion. New road or rail crossings might also be added, raising the costs, and there would be a need for extra flood control and waste-water/sewage clean up, although the barrage might help reduce the impact of surge tides and also reduce silt being carried in suspension. In which case, the water would be clearer, increasing the potential biological productivity, since light would penetrate more deeply.

The barrage would generate electricity on both ebb and flood tides, unlike in earlier plans. Although the total output would be less (you can't then take either cycle to completion), output would be spread over a longer period in each tidal cycle and extend the time when the mud flats were exposed by about 60%. This, and the changed water turbidity, should lessen the environmental impact to some extent, mitigating the loss of inter-tidal habitat for the bird population. In addition, given the slower rotation speeds, large fish could get through more easily.

The barrage would generate about 16.4 TWh of electricity a year, about 4% of UK needs, but of course, given the changing tidal cycle, even with ebb and flow generation, its output would not match demand patterns well, so its actually useable contribution would be much less.

In 2007 the Sustainable Development Commission suggested that overall the STPGs version would only cut UK emissions by 0.92%.

Not much for £25-30bn! You'd get better C/£ cuts from almost any other renewable option. But Cameron has evidently asked ministers to look at the proposal which, given its size, would require new hybrid bill legislation.

It seem unlikely to go ahead: if at some point there were major energy storage facilities on the grid, then the barrage might make some sense, but as I have argued before, for now it seems a poor strategic option:

In addition, many of the environmental issues still remain. RSPB have yet to decide their position, but the Green Party recently produced a report opposing the new proposal, and backing lagoons and tidal reefs/fences instead:

Friend of the Earth (FoE) have always backed lagoons as a better bet, e. g Tidal Electrics proposals for Swansea Bay,

A report from two MPs also backed lagoons and identified a whole series of potential sites in the Severn estuary:

These were free-standing fully offshore lagoons, which it is claimed would, unlike a barrage, have minimal impact - they would not slow the flow , or interfere with shipping. For some reason however, DECC has always been hostile to lagoons But It has only looked seriously at inshore projects , which partly enclose some coast line (thus saving some construction costs) FoE say these would have more environmental impact on inshore ecosystems . The DECC study of the Severn options (barrages, fences and lagoons) is at

In addition to the Severn, there have been detailed studies and comparisons made of fully offshore lagoons and of barrages elsewhere e.g for the Mersey and Solway Firth : basically the conclusion was that offshore lagoons win in terms of eco-impact, but may be more expensive/kWh, partly since they are smaller. See{3583C7D9-9EDD-4AAF-86F7-3CBC2C59A450}

There has also been a proposals for a 1GW rated £2m barrage 11 miles across the Wash: see

That is sometimes called lagoon, but it impounds the whole Wash, so its not really a lagoon in the sense used above of something in an estuary. RSPB have opposed it.

Personally I see free-standing tidal turbines (or flow turbines in permeable fences) as much better (you can scale up the numbers) , lagoons as intermediate and barrages as hopeless, especially large ones ; as the study of the STPG proposal produced for WWF and other NGO concluded, a Cardiff-Weston barrage would be about the most expensive energy option there is. See:

A critical vjew was also taken in a recent report on the new Severn Barrage proposal by renewable Regen SW and consultancy firm Marine Energy Matters, which says that tidal lagoons and tidal fences, tidal stream technology, wave and wind power could far less harmful to the environment, and provide up to 14 GW of low carbon energy capacity, more than double that of the proposed large Hafren Barrage.

Even with ebb and flow generation, it seem likely that the big barrage would still also be inflexible, still delivering large busts of power, albeit over longer periods, but still often unrelated to demand. And it would take a long time to build- maybe up to a decade, including planning. By contrast, large numbers of free standing tidal turbines can be installed quickly and incrementally at different sites around the UK coast, so as to produce a more nearly continuous net output: given the delayed tidal maxima at successive points, their peak outputs would occur at different times. At present there are proposals for up to 2GW of tidal current turbine projects at sites in and around the UK, including off Wales and Scotland. We can see how that turns out - and learn as we go. There may be a case for smaller barrages, or more likely, lagoons, but a big problem with large barrages is that it's all or nothing- you cant build half of one, and if it turns out to have problems (e.g. silting up) you maybe stuck with expensive remedial measures, or even complete failure.

Wind is still winning

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Windpower has continued to move ahead rapidly, increasingly offshore. By the end of 2011, 3820 MW of offshore wind power capacity had been installed in European waters, according to the European Wind Energy Association. Over the next three years, 18 more projects will become operational, raising the total capacity to 9,000 MW. By 2020, if all goes according to plan, EU (+Norway) offshore wind power capacity should reach 40,000 MW, meeting, on a yearly average, 4% of EU electricity demand. By 2030, the idea is to expand to 140,000 MW- around 14% of supply needs.

There has been no shortage of negative comments on what anti wind interests have portrayed as the poor economics of offshore wind. See for example Prof. Gordon Hughes report for the Global Warming Policy Foundation "'Why is wind power so expensive'; and the subsequent media debate:

However, given that using wind avoids the cost of using fossil fuel, the rival view is that, over time, wind power and other renewables will be cheaper. Even given the need to balance their variability. For example, according to a comparative study by financial group Ernst & Young (E&Y), the net cost of European wind power is up to 50% lower than that of its main conventional power rival, combined cycle gas (CCGT),

They note that in Spain, producing 1MWh will generate €56 of gross added value from wind, as opposed to €16 from CCGT. Across the six European focus countries (Spain, UK, France, Germany, Portugal and Poland), wind's net cost is competitive and, extrapolated across the EU as whole, cheaper.

By factoring in returns to GDP, like jobs and local taxes, E&Y's analysis challenges the power sector's levelised cost of energy (LCOE) standard, which always puts wind costs higher, mainly due to upfront capital costs. Gas is costlier in countries dependent on gas imports. But even in gas producing UK, E&Y puts wind's net cost only slightly above gas, at €35/MWh against €31/MWhfor gas.

Following a similar net cost approach, the UKs Mainstream Renewables have been pushing for recognition of the wider strategic benefits of offshore wind, e.g. in terms of security of supply and employment. A June 2012 Paper on the Value of Offshore Wind from the Cebr concluded that that by 2015 investment in offshore wind could increase UK GDP by 0.2%, and create over 45,000 full time jobs, by 2020, double that GDP contribution to 0.4%, and the number of people employed to over 97,000. And by 2030, in addition to adding 0.6% GDP growth, and creating 173,000 jobs, deliver an increase in net exports of £18.8 billion, covering nearly 75% of the UK's current balance of trade deficit.

Wind critics however still insist that the net carbon saved will be low, due to the need for back up plants. Indeed Prof. Gordon Hughes says that ' to maintain secure reserve margins, each MW of wind generating capacity has to be backed by approximately 1 MW of generating plant which can be run on demand. There is absolutely no saving in CO2 emissions because the gas plants carry on running as before but they are just feeding less electricity into the grid'.

This seems odd: varying the output from CCGT gas plants may reduce their efficiency to some extent, but when not delivering full power, they use less fuel, so producing less CO2. And you don't have to back up each individual turbine: it's variations, and the usually differing variations from others at other sites, will be aggregated by the grid, with wind's capacity credit being around 20% for a 20% wind contribution. In addition there are many other grid balancing options (e.g. demand management, energy storage .imports from interconnectors), so CCGTs don't have take all the strain. And in any case there are new flexible CCGTs emerging which can ramp up and down rapidly with much less loss of efficiency than existing designs medium=feed&utm_campaign= Feed%3A+IeeeSpectrum+%28IEEE+Spectrum%29

So, overall, for range of reasons, CO2 savings will still be high and could be further increased if renewable energy sources were used to provide the backup e.g. biogas-fired CCGTs . One study suggested just a 2% reduction to net emissions saved due to emissions from backup plants, with 20% of wind on the grid, though higher with more. Others put it a bit higher, but still much less than the net carbon saved. Here is a DECC view

There is no question that, as wind and other variable renewables expand, then the balancing issue will become more important, but with judicious selection of technologies and the development of smart grid infrastructure and supergrid links, it should not be a major problem. The real issue is which supply technologies to focus on. On land wind is the cheapest major new renewable at present, but many see PV solar coming up fast behind. Germany now has 30GW of each. Their availability patterns compliment each other to some extent, even if the location of the best resources differ (wind in the north solar in the south), so that cross-country grid links need to be improved.

However, there are also other perspectives to consider. Germany is pushing ahead rapidly with biogas production, including green methane and other green synfuels derived from excess wind and solar electricity. Some of these green fuels can be used for heating but some can be stored, or sent where they are needed using the gas main, and then used in gas plants for backing up wind and PV solar. Or in CHP plants to do both, linking to local district heating networks. A whole new system of energy supply, storage, transmission and use could emerge, with wind, and solar, only being a part, and with wide integration across the EU enabling grid balancing. See DENAs "Integration of Renewable Energy Sources into the German-European Electricity Market" and

2012 saw renewable energy being taken increasingly seriously as a major new energy option, if not the major new nergy option. There is now 238GW(e) of wind capacity in place globally, 245GW(th) of solar thermal heating and 70GW of solar PV and rapid expansion continues, despite the global recession, with wind capacity expected to double over the next five year and PV solar perhaps treble.

'The share of renewable energy in global primary energy could increase from the current 17% to between 30% to 75%, and in some regions exceed 90%, by 2050.' So said the Global Energy Assessment (GEA) produced by an international team led by the International Institute for Applied Systems Analysis. The report (which I mentioned in an earlier Blog) is now on line at:

The International Energy Agency also saw renewables as likely to boom They could "become the world's second-largest source of power generation by 2015 and close in on coal as the primary source by 2035", according to the 2012 edition of the IEA World Energy Outlook . It says that global nuclear capacity will reach some 580 GWe in 2035- 10% less than the IEA forecast in 2011. And with demand for power rising, the global share of nuclear in total generation will fall from 13% to 12%. By contrast it says renewables' share of electricity generation will grow from 20% in 2010 to 31% by 2035.

Even so, overall it felt much more needed to be done to face up to climate change,

So how is this paying out in practice? Germany is the obvious test case, given its aim to get 80% of its electricity from renewables by 2050. It is sometimes said that Germany's attempt to phase out nuclear and replace it with renewables will in fact just lead to more use of fossil fuels- imported gas and indigenous coal. So carbon emissions will rise. In reality however, emissions have actually continued to fall. In 2011, GHG emissions were 26.5% down from 1990, with a 2.1% year on year decline, and that has continued into 2012, despite the closure of eight nuclear plants article/2012/04/12/germany-emissions-idUSL6E8FC53420120412 .

German use of coal to generate electricity declined steadily from 56.7% in 1990 to 43.5% in 2011, a decrease of more than 10% despite an increase in total electricity generation during the same period of about 10%. Coal use went up slightly in late 2011 early 2012 (during an exceptionally cold winter), but the emission reductions seem likely to continue in part because the share of renewable energy in the electricity mix has increased from 3.6% to 19.9%, mostly due to the rapid development of wind energy and PV solar, plus biomass. Wind and PV and now both at 30GW! The current renewables target has now been expanded from 35% of electricity by 2020 to 40%.

As energy analyst Paul Gipe (see his Wind works web site below) has noted, German renewable generation now exceeds generation from hard coal and generation from nuclear. Although total renewable generation was less than brown coal in 2011, on present form, renewable generation may exceed that from brown coal by 2015. Gas is more of a problem, but wind and gas seem to be running about equal and there are ambitious plans for wind-to-gas projects, converting excess wind derived electricity into storable hydrogen and then into a range of synfuels, this providing a way to deal with the variability of wind and replace fossil gas and oil use in key sectors. and

There is no doubting that it will be hard to expand renewables fast enough to keep emissions down, while closing the rest of the nuclear plants by 2022, and there is no shortage of negative views about the how the cost will be distributed. However on current form, good progress is being made, not least due to the reduce costs of the key technologies. That has meant that the level of Feed-In Tariff (FiT) support for wind has now be reduced, as had already be done for PV solar. Obviously if the tariffs had remained high, then more capacity would emerged faster, and some see the cut backs as having been too harsh, and as a retreat in the face of political challenges and concerns about the cost to consumers, already faced with large increases in fuel costs. However they can also be seen as a refection of the fact that the FiT system have worked in getting prices down, so that FiT levels can now be reduced.

What happens next? Well, much of the rest of the EU is also pushing ahead with renewables like Germany, while Japan is in some ways following the same route as Germany, although starting from a lower level, aiming to phase out nuclear in the 2030s and backing an ambitious 25 GW renewables programme, using FiTs. As I reported previously, the USA is also a major force, but China leads the pack, with 62GW of wind already in place and ambitious plans for expansion across the board. The Chinese government recently increased its target for solar energy by 40%, pledging to deploy 21GW of capacity by 2015.

Overall, a study reported in the Springer journal Sustainability Science (Volume 7, Number 2 / July 2012) on 'Socio technological transitions towards sustainable energy and climate stabilization', suggest that it is possible to cut global Greenhouse gas emissions by 50% by 2050, with renewables playing a major role. In one scenarios solar, wind, biomass power generation, and biofuels, along with CCS, together account for 64 % of the total GHG emission reduction in 2050.

For overviews see and And for the technological feasibility and costs:

A 50% emissions cut back would be good, but its conceivable that more could be achieved, given a proper commitment to renewables and energy saving- the later being highlighted recently by the IEA as something that needed a lot more extra effort. So, as a new years resolution, in my 2013 coverage, as well as renewables, I will be looking at energy efficiency more, starting as soon as I get chance, with the situation in the UK.

Parts of the above were submitted as a Guest editorial for a forthcoming issue of the International Journal of Ambient Energy, of which I am a editorial board member: