Category Archives: carbon emissions

Can nuclear power play a large part in getting to net-zero? – Professor Gordon MacKerron

carbon emissions, Economics, energy bills, Energy Systems, integrated energy systems, multi-vector energy systems, Net Zero, Nuclear, Policy, Power

In late 2020, there was a flurry of announcements about climate change and energy – first a ten-point plan for a ‘Green Industrial Revolution’[i] followed a few weeks later by a much–delayed energy White Paper[ii].  Nuclear power figures prominently in both narratives, with three possible ways forward. In this CESI Blog post, Professor MacKerron, CESI Associate Director and Professor of Science and Technology Policy at the Science Policy and Research Unit (SPRU) at the University of Sussex discusses these routes.

About the Author

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Professor Gordon MacKerron

Gordon is Professor of Science and Technology Policy at the Science Policy and Research Unit (SPRU). He specialises in the economics and policy issues of electricity, especially nuclear power, and more broadly in energy security questions. He currently chairs the Research Committee of UKERC and was deputy director of the Strategy Unit, Cabinet office team that wrote the ‘Energy Review’ in 2003.

He is currently overall PI in the Horizon 2020 project TRANSrisk, a collaboration of 11 partner institutes engaged in assessing the risks attaching to different policy pathways consistent with achievement of European 2050 climate change commitments.

Gordon works on a number of CESI Work Packages and is lead for Work Package 1: Commercial, Regulatory & Policy Aspects

Three possible ways forward.

First, there is a long-term hope that a UK-only commercial fusion design will be ready by 2040.  This is frankly wishful thinking and, even if it could be achieved, involves a new type of compact design that would have no impact on 2050 zero-carbon objectives.  This is because it would be a small prototype 100MW machine with a current price tag of £2bn[iii] – three times more expensive per unit of output than the already very expensive twin reactors being built at Hinkley C.  £400m has been ‘already committed’ to this endeavour by Government,[iv] a sum that could have been spent instead on projects that could genuinely contribute to net zero. 

The second possibility is a push (‘aim’) to have one more large nuclear plant brought to final investment decision by 2024, following the almost-decade-late Hinkley C.  As Government makes clear, achieving this will depend on a radically new funding structure.[v]  This could be a regulated asset base model, in which consumers would take on most construction risk, allowing investors a more or less guaranteed rate of return, and/or  Government putting up some taxpayer cash.  Since the White Paper, it has become clear that developments at two of the only three plausible big-reactor sites – Wylfa (abandoned by Hitachi) and Bradwell (paused for a year by EDF/China General Nuclear) – are now effectively no longer in contention.  Only a further Hinkley replica at Sizewell seems at all possible, and large institutional investors have recently made clear they will not put up any of their own money for this.  Significantly, and credibly, Government makes no mention of any further ventures along the large-nuclear path.

What’s wrong with option 1 or 2?

The problems in these two nuclear avenues inevitably throw a lot of weight on to the third strand, the development of so-called modular reactors, both ‘small’ (SMRs) and ‘advanced’ (AMRs).  The relatively near-term part of this involves Government spending up to £215m to help develop a domestic SMR design by the early 2030s.[vi]  The attraction of SMRs is that they could offer the possibility of relatively rapid factory manufacture of components, followed by fairly simple on-site construction. Their main drawback is that they will be based on cut-down versions of existing light water reactor designs, in the process losing the economies of large-scale current nuclear plants. In practice the only credible SMR involves a consortium already built up over several years by Rolls Royce, using its technical know-how as designer and manufacturer of small reactors for UK nuclear-powered submarines. To be at all competitive many SMRs would need to be built, thus achieving economies scale in production to offset the loss of economies of large reactor size. In this pursuit, Rolls Royce want to build up to 16 of these SMRs at a cost currently estimated by them[vii] (and therefore probably optimistic) of just short of £29bn.  This is a highly inflexible proposition, risking very large sums of public money.

Rolls Royce have also suggested that such reactors might generate at around £60/MWh initially, falling to £40/MWh for later plants.[viii]  By contrast, in terms of real projects, as opposed to very early and potentially optimistic expectations, offshore wind is already committing to deliver in the near-term at auction prices of around £40/MWh.[ix]  According to the White Paper, the global market for modular and advanced reactors might (as ‘estimated by some’ – actually the National Nuclear Laboratory) be worth £250bn to £400bn by 2035.  This is at best heroic, given that the current global market is zero. In any case, the idea that the UK might win a large share of such a market (if it did exist) is made hopelessly implausible by the fact that the UK is well behind several other countries’ SMR development. These include Russia, the USA, Japan and China, with the Rolls Royce planned design only one among over 70 SMR designs currently being pursued around the world.[x]

The second leg of the modular reactor story involves ‘Advanced’ reactors.  The ambition here is to have a demonstrator ready by the early 2030s ‘at the latest’.  For this, the Government may be willing to spend a further £170 m.  Here we are in highly speculative territory.  As the White Paper very briefly explains, AMRs would be reactors that use ’novel cooling systems or fuels and may offer new functionalities (such as industrial process heat).’[xi] Such designs would most likely involve high temperature gas cooling; many such designs have been developed in the past 50 years, none of them proving commercially viable.  It is not clear why work in these challenging technological areas can be expected to do much better in the future.  Even if such technologies eventually prove more commercially tractable, having a demonstrator built by the early 2030s is extremely hopeful. 

Optimism?

The optimism displayed in these plans includes the up-front claim that ‘the UK continues to be a leader in the development of nuclear technologies’[xii] – a proposition, when applied to commercial reactors, that has no basis in fact whatever.  However, Government does qualify its enthusiasm by making clear that its plans, including expenditure, remain conditional. For a large reactor, bringing a project to fruition depends on ‘clear value for money for both consumers and taxpayers’[xiii] and the £385 m apparently to be spent on SMRs and AMRs reactors is ‘subject to future HMT [Treasury] Spending Reviews’.[xiv]  But even if all nuclear plans worked out as the White Paper hopes – in terms of developing new low-carbon capacity on the predicted time-scale – it is far from clear that this would be achieved at anywhere near competitive cost.  Even if nuclear power does well, large reactors will play, at best, a very small part in the move to net zero carbon by 2050. While modular reactors could do more, there is huge uncertainty, probable extended timelines and no guarantee of any kind of success.

[i] HM Government (2020) The Ten Point Plan for a Green Industrial Revolution November

[ii]  HM Government (2020) The Energy White Paper. Powering our Net Zero Future December CP337

[iii]  ‘UK takes step towards world’s first nuclear fusion power station’ New Scientist, 2 December 2020.  Numbers are quoted from the UKAEA, the fusion R&D proponent

[iv]  The Energy White Paper, p. 51.

[v]  Ibid., p. 49

[vi] ibid. p. 50

[vii] World Nuclear News ‘Rolls Royce on track for 2030 delivery of UK SMR’ 11 February 2021

[viii]  ibid.

[ix]  https://www.greentechmedia.com/articles/read/prices-tumble-as-u-k-awards-5-5gw-of-offshore-wind

[x] IAEA Advances in SMR technology development 2020 September 2020, in which 72 designs are listed

[xi] The Energy White Paper, p. 51

[xii] ibid. P.50

[xiii] ibid. p.49.

[xiv] ibid. p.50

Techno-Economic-Environmental Analysis of A Smart Multi Energy Grid Utilising Geothermal Energy Storage For Meeting Heat Demand

carbon emissions, Energy Systems, Gas, Heat, integrated energy systems, multi-vector energy systems, Net Zero, Uncertainty, , ,

Researchers based at Newcastle University from the EPSRC National Centre for Energy Systems Integration (CESI) and the Supergen Energy Networks Hub (SEN), Dr Seyed Hamid Reza Hosseini and Dr Adib Allahham, along with the Coal Authority, Dr Charlotte Adams, will soon publish their journal paper in IET Smart Grid.

About the author: Dr Adib Allahham

Dr Adib Allahham

Dr Adib Allahham is a Research Associate within the Power Systems Research Team, School of Engineering, Newcastle University and currently works on several projects including the EPSRC National Centre for Energy Systems Integration (CESI) and the Supergen Energy Networks Hub (SEN). Adib received his PhD from the University of Joseph Fourier in the field of control engineering. His research involves projects around the electricity distribution and off-grid power sector and multi-vector energy systems. These projects are addressing the need to cost-efficiently decarbonise the energy sector over the next thirty years by facilitating innovative network integration of new generation, and the integration of different energy vectors (electricity, gas, and heat). Computer simulation, laboratory investigation and demonstration projects are used together to produce new knowledge that delivers this requirement. He has published more than 25 technical papers in leading journals and conferences.

Contact details:
adib.allahham@ncl.ac.uk
@adiballahham
Profile details

About the paper

The UK Government has committed to a ‘Net Zero’ carbon economy by 2050 [1]. One major source of carbon emission is associated with heat demand from the domestic, commercial and industrial sectors.

Providing for heat demand accounts for around one third of UK carbon emissions [2]. In order to decarbonise the provision of heat, it is essential to increase the penetration of Low Carbon Energy Sources [1] in Smart Multi Energy Grids (SMEGs), i.e. integrated gas, electricity, and district heating and cooling networks [3,4]. This, consequently, has impact on the operation of SMEGs from the Techno-Economic-Environment (TEE) point of view [5,28].

Recent work on the geothermal potential of the UK’s flooded abandoned mining infrastructure has revealed a subsurface resource in place of 2.2 million GWh [11]. The impact of integrating this vast supply and storage potential on the operation and planning of SMEGs needs to be evaluated in terms of TEE aspects.

The paper identifies research gaps, including neglecting the electricity requirements of the components of the geothermal system that is required to boost the hot water quality and presents an evaluation framework for the Techno-Economic-Environmental (TEE) performance of Integrated Multi-Vector Energy Networks (IMVENs) including geothermal energy. Geothermal Energy Storage (GES), offers huge potential for both energy storage and supply and can play a critical role in decarbonising heat load of Smart Multi Energy Grids.

Schematic of SEH, GN & DHN
Fig.1 Schematic of the considered Smart Electricity Network (SEN), Gas Network (GN) and District Heating Network (DHN)

The two most common types of GES, i.e. High Temperature GES (HTGES) and Low Temperature GES (LTGES), were modelled and integrated within the framework which evaluates the impact of different low carbon energy sources including HTGES, LTGES, wind and PV on the amount of energy imported from upstream, operational costs and emissions of IMVENs to meet the heat load of a region.

Data from a real-world case study was used to compare the TEE performance of the considered IMVEN configurations for meeting the heat load. Data included wind and PV generation, as well as the heat and electricity load for a representative winter week of a small rural village in Scotland.

Fig. 2 The schematic of all the possible configurations of IMVEN considered in this paper

The results reveal that the most efficient, cost effective and least carbon intensive configurations for meeting the heat load of the case study are the configurations benefitting from HTGES, from a high penetration of heat pumps and from LTGES, respectively.

References

  1. [1] ‘Net Zero – The UK´s contribution to stopping global warming’, https://www.theccc.org.uk/wp-content/uploads/2019/05/Net-Zero-The-UKs-contribution-to-stopping-global-warming.pdf, accessed 20 December 2019
  2. [2] ‘Clean Growth – Transforming Heating: Overview of Current Evidence, https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/766109/decarbonising-heating.pdf, accessed 20 December 2019
  3. [3] Ceseña E.A.M., Mancarella P.: ‘Energy Systems Integration in Smart Districts: Robust Optimisation of Multi-Energy Flows in Integrated Electricity, Heat and Gas Networks’, IEEE Transactions on Smart Grid, 2019, 10, (1), pp. 1122-1131
  4. [4] Lund, H., Andersen, A.N., Østergaard, P.A., et al.: ‘From electricity smart grids to smart energy systems – A market operation based approach and understanding’, Energy, 42, (1), pp. 96-102
  5. [5] Hosseini, S.H.R., Allahham, A., Taylor, P.: ‘Techno-economic-environmental analysis of integrated operation of gas and electricity networks’. Proc. IEEE Int. Symposium on Circuits and Systems (ISCAS), Florence, Italy, May 2018, pp. 1–5
  6. [28] Hosseini, S.H.R., Allahham, A., Walker, S.L., et al.: ‘Optimal planning and operation of multi-vector energy networks: A systematic review’, Renewable and Sustainable Energy Reviews, 2020, 133, 110216
  7. [11] Adams, C., Monaghan, A., Gluyas, J.: ‘Mining for heat’, Geoscientist, 2019, 29, (4), pp. 10-15

Energising our lives – a WES 100 Violets Challenge project – the continuing story

built environment, carbon emissions, EDI, Energy Systems, integrated energy systems, Net Zero, STEM outreach, Transport

Engineering is key to find answers to the challenges we face today! From the climate emergency to the medical and humanitarian response to the global pandemic, collaborating engineers are playing a significant role in developing solutions.

Newcastle University researchers, Dr. Jannetta Steyn and Laura Brown have worked together on a WES 100 Violets Public Engagement Challenge project, to illustrate the solutions and ideas engineers are applying to the global need for clean and affordable energy and integrating technology to improve the quality of our every life.

About WES

The Women’s Engineering Society (WES) is a charity and a professional network of women engineers, scientists and technologists offering inspiration, support and professional development. Working in partnership, it supports and inspires women to achieve as engineers, scientists and as leaders; they encourage the education of engineering; and support companies with gender diversity and inclusion.

About WES 100 Violets Challenge

The Women’s Engineering Society’s (WES) 100 Violets Challenge competition was part of their centenary celebrations in 2020. The aim was to design and build an engaging museum exhibit that celebrates and showcases engineering/research and shares it with the public. The challenge is supported by the Ingenious Grant program from the Royal Academy of Engineering.

Building the exhibit

Please see our first blog post to find out more background about the project idea. https://blogs.ncl.ac.uk/cesi/2021/01/29/wes-100violets-part1/

More Technical Details about the project can be found in a series of blogs developed by Jannetta at her personal blog site: – brainwaves.jannetta.com

The aim of the exhibit was to showcase electrical, software, computing, mechanical, building, transport and energy engineering. So no pressure then.

The Energy System Integration Vision

About the Project Team: Dr Jannetta Steyn

Jannetta is a Research Software Engineer at the Digital Institute, Newcastle University. As an experienced researcher and software engineer she has a background in data analysis, provenance and middleware programming. Jannetta does a large amount of outreach work, primarily in STEM, running a range of coding clubs and electronics clubs.

Contact:- Jannetta.Steyn@newcastle.ac.uk

http://brainwaves.jannetta.com/

About the Project Team: Laura Brown

Laura is the Centre Manager, EPSRC National Centre for Energy Systems Integration and Energy Research Programme Manager, Newcastle University. Her research tackles the challenges of integration of state-of-the-art thinking and technology into legacy and future energy systems. Laura sits on the Tees and Tyne Regional Cluster Committee of the Women’s Engineering Society and is the group leader of the SDG7 subgroup of the WES Climate Emergency Group.

Contact:- laura.brown11@newcastle.ac.uk

Our first outing

By way of practice for the WES 100Violets Exhibition planned for April 2020, we were lucky enough to be offered a chance to “trial” the exhibit at the opening event of the Gateshead Library Makerspace. We were delighted that the training we have been given by WES had come in very useful, particularly the risk assessment guidance. This meant we had planned carefully the storage requirements, labeling and cable routes for the equipment for our exhibit.

Jannetta writing some code for the IoT with a young helper adjusting our Lego Engineers

The event went well but underlined what we suspected:- KIDS LOVE LEGO. It proved to be a popular exhibit. And, while it might have been the draw of the remote control car (with its own garage), the Bluetooth controlled train or the eye-catching rotating wind turbine, all of the young people we spoke with left knowing just a little bit more than they did about renewable energy and role of women in engineering and computing.

So how do these technologies work in real life?

Part of the purpose of the exhibit was to provide educational information on the energy system. So we had been working on a number of learning resources that we thought might help engage the visitors to the exhibition. We had planned to have ‘make your own’ wind mill; colouring sheets; spot the energy competitions and possibly a 3D printing demo session.

It was all looking good but then as the date for the main event drew near, the impact of the pandemic was starting to reach home. The organisers took the difficult but inevitable decision to postpone the exhibition.

How does a wind turbine produce electricity? https://archive.epa.gov/climatechange/kids/solutions/technologies/wind.html
  1. As the wind blows over the blades of a wind turbine, it causes the blades to lift and rotate.
  2. The rotating blades turn a shaft that is connected to a generator.
  3. The generator creates electricity as it turns.

Some great STEM resources out there to explain energy

As part of our research we found some very useful STEM resources that we would highly recommend for anyone looking to understand more about their own energy system.

  1. BBC Bitesize – Humans and the Environment https://www.bbc.co.uk/bitesize/topics/zp22pv4
  2. NASA’s Climate Kids https://climatekids.nasa.gov/menu/energy/
  3. CALTECHs Energy STEM resources https://www.jpl.nasa.gov/edu/learn/tag/search/Energy

So what now

While cancelling the event was most definitely the right thing to do, all the groups from the WES competition were disappointed. Lockdown meant our team couldn’t even get onto campus to check our equipment and work further on the exhibit. Everything paused.

When the North East of England partially removed the lockdown in the summer, Jannetta collected all the components of the exhibit to have at home. So after the most recent national lockdown and encouraged by Dr Jo Douglas-Harris, the WES Tees and Tyne Cluster Chair, we looked for alternative ways to ‘tell the story’ of the project and share the vision. The new aim: let’s try to exhibit virtually. A new challenge for us both.

So for the last month of so, in our rare moments of spare time and in our evenings, we have put together some materials and collated the reflections and learning from the project in two blogs (this one and that one (https://blogs.ncl.ac.uk/cesi/2021/01/29/wes-100violets-part1/)). And we are going to trial exhibiting virtually via a livestream on CESI’s YouTube Channel.

https://www.youtube.com/channel/UCcKtJZLFUsCXYGuJ62evBkA

The EPSRC National Centre for Energy System Integration (CESI) YouTube Channel

Event Details

Image

And we’ve got an accompanying YouTube video too.

https://www.youtube.com/watch?v=_slWTm_zEhI

We look forward to hearing what you think.

How green is energy storage? Learnings from a CESI-funded case study

carbon emissions, Energy Storage, Energy Systems, integrated energy systems, Net Zero, Power, , , , ,

Academics funded by the EPSRC National Centre for Energy Systems Integration (CESI) in the Centre’s first Flexible Funding Call, recently published the results of a study on the impacts of energy storage operation on greenhouse gas emissions, in the journal Applied Energy. Their work is summarised here by the lead author, Dr Andrew Pimm, and the full paper [1] is freely available to all on the journal website. The research team was led by Prof Tim Cockerill of the University of Leeds, and also included Dr Jan Palczewski of Leeds and Dr Edward Barbour of Loughborough University.

About the author: Dr Andrew Pimm

Dr Andrew Pimm is a Research Fellow at the University of Leeds investigating the techno-economics of energy storage, energy flexibility, and industrial decarbonisation. Prior to joining Leeds in 2015, he worked on the development of grid-scale energy storage technologies at the University of Nottingham, where he was involved in offshore trials of underwater compressed air energy storage.

Contact details
Email: a.j.pimm@leeds.ac.uk

Energy storage will be a key part of the future energy system, allowing the deployment of higher levels of non-dispatchable low carbon electricity generation and increased electrification of energy demand for heating/cooling, transport, and industry.

Passing energy through storage inevitably results in losses associated with inefficiencies, however previous investigations have found that operation of electricity storage can result in increased CO2 emissions even if the storage has a turnaround efficiency of 100% [2]: if the output from a relatively high carbon source (such as unabated gas or coal) is increased to charge the storage, and the output from a relatively low carbon source is reduced when the storage is discharged, then the result will be a net increase in CO2 emissions.

However, these effects had not been considered recently for Great Britain, and little attention had been given to the extent to which they vary by location. We sought to fill this gap in the knowledge through our study.

We made use of data from National Grid’s regional Carbon Intensity API and ELEXON’s P114 dataset to determine the source of electricity consumed in each of Great Britain’s 14 electricity distribution zones for each half-hour period in 2019 (annual sums shown in Figure 1).

Figure 1: The share of electricity consumption by region and source in Great Britain in 2019.

With these data, we used linear regression techniques [3] to calculate half-hourly “marginal emissions factors” for each distribution zone. These tell us the change in CO2 emissions that occurs as a result of a change to grid electricity demand, disaggregated by time and location. These regional marginal emissions factors were then used to assess the impact of electricity storage operation on grid CO2 emissions in three different storage operating scenarios:

  1. Load levelling, whereby storage is charged at times of low demand and discharged at times of high demand.
  2. Wind balancing, whereby storage is charged at times of high wind output and discharged at times of low wind output.
  3. Reducing wind curtailment, whereby storage is charged using excess wind generation that would otherwise be curtailed and discharged at times of high demand.

The resulting emissions reductions are shown for selected distribution zones and Great Britain as a whole in Figure 2. Wind balancing is the only storage operating mode that leads to increased CO2 emissions, and emissions are reduced the most when storage is operated to reduce wind curtailment in regions with high levels of fossil generation.

Across all regions and operating modes, the difference between the highest reduction in emissions and the highest increase is significant, at 741 gCO2 per kWh discharged, and is roughly equivalent to the reduction in emissions per unit achieved by fitting a coal power plant with carbon capture and storage.

Figure 2: Potential emissions reduction through storage operation for the three operating scenarios, in six selected distribution zones and Great Britain as a whole in 2019.

While electricity storage will be a key component in future low carbon energy systems, our work has shown the importance of storage location and operating mode to its operational emissions and the possible dangers of evaluating emissions using average emissions factors. We are currently using these new techniques to investigate the lifecycle emissions of storage and smart EV charging across the EU.

References

[1] Pimm AJ, Palczewski J, Barbour ER, Cockerill TT. Using electricity storage to reduce greenhouse gas emissions. Applied Energy. 2021;282:116199.
[2] Denholm P, Kulcinski GL. Life cycle energy requirements and greenhouse gas emissions from large scale energy storage systems. Energy Conversion and Management. 2004;45:2153-72.
[3] Hawkes AD. Estimating marginal CO2 emissions rates for national electricity systems. Energy Policy. 2010;38:5977-87.

Achieving net-zero in the UK through an integrated energy system

carbon emissions, Energy Systems, integrated energy systems, multi-vector energy systems, Net Zero, , , , ,

The Communities Secretary, Rt Hon Robert Jenrick MP, recently rejected permission for an open cast mine near Druridge Bay, stating that the proposal “is still not environmentally acceptable”. This announcement follows a lengthy decision process and extensive media coverage, including a Public Inquiry and an appeal to the High Court. In this blog CESI Director, Dr Sara Walker, comments on the case which was supported by evidence presented by CESI’s previous Director, Prof Phil Taylor on CESI’s whole systems approach to energy systems integration.

Druridge Bay, Northumberland

About the author: Dr Sara Walker

Dr Sara Walker is Director of the EPSRC National Centre for Energy Systems Integration, Director of the Newcastle University Centre for Energy and Reader of Energy in the University’s School of Engineering. Her research is on energy efficiency and renewable energy at building scale.

Contact details
email: sara.walker@ncl.ac.uk

In 2014, a proposal was put forward to remove 3 million tonnes of coal from an opencast mine at Highthorn, close to Druridge Bay, on the Northumberland coast. The proposed developer, HJ Banks & Co Ltd, argued coal fired power stations are essential for the security of the UK’s energy supply and in July 2016, planning permission for the mine was approved by Northumberland County Council.

In a landmark move, central Government called a Public Inquiry on the grounds of climate change – the first time any planning permission decision has been called to inquiry on this basis.

In March 2018, the Communities Secretary Sajid Javid stated he had concluded the project should not go ahead on the grounds that it would exacerbate climate change. This rejection was the first time any planning permission decision has been refused on this basis, setting a precedent for all future applications.  This was seen as a significant step in taking tackling climate change seriously, showing the UK to be leading in this regard.

Following the announcement of the planning rejection, Banks lodged an appeal in the High Court.  The High Court found in favour of Banks in October 2018, returning the case to the Communities Secretary to reconsider the arguments presented.

At the Planning Inquiry, the expert witness for Banks argued that if coal fired power stations are phased out, a significant number of new gas fired power stations would be required, providing 7GW of gas generation. They also claimed other cleaner sources of energy cannot be relied upon as a consistent source of energy. Wind power, for example, provides an intermittent source of energy as the wind does not always blow. Similarly, the sun does not always shine, so photovoltaic systems will not generate sufficient energy. For these reasons, opening the new mine would have been an important step in ensuring that the UK maintains a good supply of coal for its power stations. However, there is no single source of fuel that provides the energy to satisfy the whole of the UK’s energy requirements. Instead, it is essential to take a whole systems approach when considering the UK’s energy mix.

The Department for Business, Energy and Industrial Strategy (BEIS) collates data on the UK’s energy generation mix.  The latest figures were released in July 2020 [1] and compare data for 2019 against previous years.  The shares of electricity generation by fuel in 2018 and 2019 are illustrated in Figure 1. These show that gas generated electricity increased slightly to 40.6%.  Electricity from renewables (wind, hydro, solar, wave, tidal and bioenergy) achieved a record high of 37.1% (121TWh), which is the first time renewables have provided over a third of the total generation mix. During the same period, the share of electricity generated from coal reduced to 2.1% (6.9TWh).  This represents a record low, down 59% compared to 2018.  The figures show that coal is declining in importance and that we have many options to replace it.

Figure 1 The share of electricity generation by fuel in 2018 and 2019 [1]

An integrated energy system

In his expert witness testimony to the Public Inquiry, CESI’s former Director and current Associate Director, Professor Phil Taylor, emphasised the need to take a whole systems view, highlighting CESI’s research into an integrated energy system. The UK can phase out coal-fired power stations by increasing the utilisation of existing gas facilities plus a small increase in capacity in power from gas and combining this with power produced from renewables such as wind, biomass and PV. We can store energy when we have more than is needed, or when there is too much for network cables to carry, and then release it when is required. Britain also imports electricity via physical links known as interconnectors. The UK energy regulator, Ofgem, forecasts that planned interconnector projects will lead to a capacity of 7.3GW by 2021 (compared to total GB system generation capacity of 77.9GW in 2019). In addition, the electricity demand could be managed through Demand Side Response (DSR), where consumers are given incentives to reduce their energy demand by reducing usage or turning off non‐essential items when there is a peak in electricity demand.

CESI evidence therefore showed that, by balancing supply and demand on the electricity grid, we can phase out coal and reduce the need to build new power stations. An additional benefit of decarbonising our energy system more rapidly is that this offers the opportunity to also decarbonise our transport and heat sectors.

“We are delighted that evidence provided by the National Centre for Energy Systems Integration has supported this landmark decision to reject further extraction of coal on grounds of Climate Change. Our work has clearly demonstrated that a Whole Systems approach with Systems Integration can enable us to decarbonise our energy systems whilst maintaining reliability and security of supply”

Director of CESI, Dr Sara Walker

Net Zero

In September 2020, the Communities Secretary, Rt Hon Robert Jenrick MP, rejected the open cast mine, stating that  the “substantial extent of the landscape harm means that the proposal is still not environmentally acceptable, nor can it be made so by planning conditions or obligations”. 

This decision will help the UK to achieve its target to phase out coal by 1 October 2024, announced by Prime Minister Boris Johnson in February 2020. It will also the support the ambitious aims of cutting carbon emissions targets set by councils in the North East of England.  These include Northumberland County Council, which has set the target of being carbon neutral by 2030.  The implications of this decision for our future energy supply are significant and will affect us all.

——————————–

  1. Digest of United Kingdom Energy Statistics 2020, Department for Business Energy & Industrial Strategy https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/924591/DUKES_2020_MASTER.pdf [accessed 9/10/2020]

How far does the Ofgem Decarbonisation Action Plan support the transition to a net zero UK?

carbon emissions, Energy Systems, Net Zero

Dr Sara Walker and Professor Janusz Bialek comment on the recently published Ofgem Decarbonisation Action Plan.

About the authors

Dr Sara Walker is Associate Director of the EPSRC National Centre for Energy Systems Integration, Director of the Newcastle University Centre for Energy and Reader of Energy in the University’s School of Engineering. Her research is on energy efficiency and renewable energy at building scale.

Contact details: sara.walker@ncl.ac.uk

Profile details

Professor Janusz Bialek FIEEE is Professor of Power Energy Systems in the School of Engineering, Newcastle University. Janusz’s background is in power systems but he has closely collaborated with economists, mathematicians and social scientists. He has published widely on technical and economic integration of renewable generation in power systems, smart grids, power system dynamics, preventing electricity blackouts and power markets.

Contact details: janusz.bialek@ncl.ac.uk

Profile details

While most our worries relate now to the COVID-19 pandemic, we should not forget about the biggest long-term threat to the human race – the climate emergency. In this blog we comment on a recently published “Ofgem decarbonisation action plan” which is a welcome opportunity to see the thoughts of the regulator on the unprecedented need for rapid transitions in our energy systems.

The plan provides some context to the 2050 net zero target with a graph (Fig. 1), showing a 40% reduction in GHG emissions over the period 1990 to 2017. However, the linear reduction proposed from 2017 to 2050 is perhaps misleading the sector in thinking the 27 year 40% reduction to 2017 is similar to the rate of change we now need moving forward. This is not the case, we need an exponential decrease in emissions if we are to come close to the targets set by the Conference of the Parties in Paris. Also it should be appreciated that the closer we get to the net-zero target, the more difficult and costly it will be to reduce the emissions any further. The reason is that once the cheapest means have been exhausted (so-called low-hanging fruits), more expensive ones will have to be used.

Source: Ofgem (2020) Ofgem decarbonisation action plan. London, Ofgem.

Much of the discussion in the Ofgem plan talks about the need for better interconnection across the energy vectors, and across uses/users. In discussing the power sector, the report refers to key scenarios in the Committee on Climate Change (CCC) report and therefore Ofgem assume Carbon Capture and Storage is needed in order for gas generation to continue. This is an area of contention for the CCC report, since Carbon Capture and Storage technology is currently not commercially available. Alongside gas is nuclear generation, and the Ofgem report assumes nuclear and gas will generate 50% of the UK’s electricity needs. The competitiveness of new nuclear is uncertain, with new offshore wind prices under the Contracts for Difference Scheme being cost competitive with the fixed price of electricity to be generated by the new Hinkley power plant (although one has to acknowledge that nuclear power provides a better security of supply than relatively highly variable and less predictable wind power).

Greater strategic co-ordination and increased investment in generation, network infrastructure, stoppage and other flexibility services are all raised as important in the plan. However, what has not been made clear is a need for a substantial network investment in view of electrification of transport and heat. The report concentrates on the need for proper price controls for network companies but does not address the question by how much the current power network has to be expanded and how to do it in the face of fierce public opposition to construction of new lines.

To understand the problem, check the diagram below which shows seasonal variations in the demand for electricity (blue), non-daily-metered gas demand (red) and total gas demand (amber). Clearly gas demand (which largely corresponds to the heat demand) dwarfs the electricity demand both on average and in terms of seasonal variations. The Ofgem plan recommends that decarbonisation of heat be through a combination of heat pumps, hydrogen and heat networks, but that heat pumps will likely contribute the majority of the heat demand.

Source: Deakin et al (2020) Calculations of System Adequacy Considering Heat Transition Pathways (arXiv:2002.11570v1)

With regards transport, the Ofgem plan talks about the current >30 million cars in the UK in 2019, and the expected 46m electric vehicles by 2050. “Increased uptake of electric vehicles creates a rare opportunity for a win-win-win for society”. 46m electric cars in the UK by 2050 will mean significant increases in congestion, and significant increase in electricity demand, along side some (albeit reduced) emissions. We would welcome a greater emphasis on public transport, rail and the heavy and light goods vehicle sectors.
Hence electrification of heat (either directly or by heat pumps) and transport would require not only a substantial new generation capacity but also a significant strengthening of both the transmission and distribution networks. But how to do it when any attempts in the past to build a new, or even strengthen an existing, transmission line (see the case of Beauly-Denny line) led to years of arguing and public enquiries? We simply do not have time for that. This is a big elephant in the room.

Flexibility is key to minimise the overall system costs (again check the diagram above to appreciate large fluctuations in energy demand) but the needs are currently highly uncertain given the assumptions around generation from wind, solar and nuclear (all of which are relatively inflexible), along with a potential reduction in load flexibility if significant energy efficiency measures are achieved in future.

Currently the Electricity System Operator (ESO) monitors only transmission connected wind and solar generation and has no direct means of monitoring the distribution-connected generation (DG). This makes it difficult for the ESO to balance the system, and DG was already one of the contributing factors to the GB outage on 9 August 2019. The situation is becoming increasingly difficult to manage, as DG was already 1/3 of installed generation capacity in 2018 and is bound to increase more. In other countries, like e.g. Ireland, the System Operator has visibility of all plants bigger than 5 MW and we see no reasons why GB should be any different.

The Ofgem plan states that regulator has a responsibility to consider the distribution of costs for system changes, particularly for vulnerable customers. Early adopters of technology such as EVs and smart controls are better placed to benefit from energy transitions (since early adopters are usually more wealthy), and those left behind are often in the lowest socio-economic groups. If the costs and benefits of energy transitions fall on different groups, in different locations, at different points in time, then the regulator will need to consider trade-offs in light of its core priorities of protecting the environment, supporting customers, and delivering competition. Perhaps these core priorities need to be weighted, or revised, in light of the Climate Emergency.

Getting it done? The UK 2020 Budget and the support for a net-zero transition in the energy sector.

built environment, carbon emissions, Centre Introduction, Economics, energy bills, Energy Systems, Heat, Net Zero, smartgrid, , ,

About the authors:

Dr Sara Walker is Reader in Energy at Newcastle University and Director of Newcastle University Centre for Energy.

Professor David Flynn is Professor of Smart Systems at Heriot Watt University

Both Sara and David are Associate Directors of the EPSRC National Centre for Energy Systems Integration, a £20m collaborative research programme with industry and government investigating the social, ecconomic and technical value in energy systems integration.

March 2020 Budget

On 11th March 2020, the Chancellor Rishi Sunak presented to Parliament the Government budget¹. This was an opportunity for the UK Government to clearly signal its commitment to deliver on the net-zero greenhouse gas emissions target for 2050 and to also lay the groundwork for COP26 as the host nation.

Albeit the language of the previous administration associated with “industrial strategy” was dropped, the Government retained a reference to the Grand Challenges, indicating that there is likely to be continued investment into energy innovation and climate change mitigation. A key indication of this is the commitment to at least double investment in the Energy Innovation Programme.

Firstly

The first mention of issues related to energy in the Chancellor’s speech came with an announcement to continue the freeze on fuel duty. For comment on this, and other transport initiatives in the Budget, we refer you to DecarboN8’s review². In a separate announcement, Business Secretary Alok Sharma previously confirmed a £36.7 million investment to design, test and manufacture electric machines. £30 million will be used to create a national network cutting-edge centers led from Newcastle University – based in Newport, Nottingham, Strathclyde, and Sunderland – to research and develop green electric machines including planes, ships, and cars. This represents the “demonstrator” element of the Industrial Strategy Challenge Fund Driving the Electric Revolution Challenge.

And then …

The second mention of energy came in an announcement, as part of the Research and Development (R&D) spend, of £900m funding for nuclear fusion, space, and electric vehicles. As employees of research organizations, we welcome the announcement of £22bn per year by 2024-25, in research and development. However, the role of new nuclear in the Committee on Climate Change Net Zero technical report³ is relatively minor.
On housing, the Budget refers to £12.2bn for the Affordable Homes Programme over 5 years, a push for 300,000 new homes per year, and reforms to planning to accelerate development. No commitment is made to the standard of new homesª, or retrofit of existing homes, which is inconsistent with the Committee on Climate Change Net Zero report, which found that high levels of energy efficiency are needed to get close to the zero targets.

What does this mean for energy sector? 

There is a clear need to improve the quality of UK homes, in a way that reduces energy use and moves us towards heating systems that use lower-carbon fuels. We need to make urgent changes in this area, from research to improve the performance of individual technology like heat pumps, to understanding possible future housing performance and the energy needs associated with that. The EPSRC National Centre for Energy Systems Integration (CESI) is looking at these types of research challenges.

The meat of the Budget from an energy perspective is in the Budget report section on “Growing a greener economy”. There is an announcement to double the size of the Energy Innovation Programme as mentioned previously, although some of this money is for R&D and therefore likely to be included in the figures above. A further £800m was announced by the Chancellor for the development of two Carbon Capture and Storage (CCS) sites through the creation of a CCS Infrastructure Fund. CCS support was removed by previous administrations but is integral to many scenarios within the Committee on Climate Change Net Zero report.

No figures are mentioned, but the Budget report includes a new support scheme for biomethane funded by a Green Gas Levy, and a Low Carbon Heat Support Scheme to enable the installation of biomass boilers and heat pumps. £270m is promised to enable new and existing heat networks to adopt low carbon heat sources, to follow on from funding of £97m for the final year of the Heat Networks Investment Project (HNIP). There is a rise in the Climate Change Levy on gas (for 2022-23 and 2023-24). The Renewable Heat Incentive is extended to 31st March 2022. Furthermore, £10m in 2020-21 is to support the design and delivery of net zero policies and programs. Heat networks are an area of research for the EPSRC National Centre for Energy Systems Integration (CESI), and we also expect to investigate more scenarios with hydrogen and CCS now that the goal for the UK has changed from 80% to a net-zero target.

And Finally

Given the critical interdependencies of our energy infrastructure to other vital services e.g. water, transport, services from public buildings, we also see opportunities to accelerate and distribute the efforts in decarbonisation by utilising the opportunities of the Making the most of Government knowledge assets initiative. The public sector holds around £150 billion of knowledge assets (intellectual property, tech, data, etc.), which is vital in shaping the operation and planning of decarbonised services. However, the absence of any Budget support for solar, wind, and storage – elements seen as vital with renewable generation four times current levels in some Committee on Climate Change scenarios – is of great concern. As is the lack of investment to decarbonise the building stock.

Getting it done isn’t the same as getting it right. And for the UK energy sector, there is very little in the budget which gives confidence that we are doing enough, let alone doing it well.

References

  1. https://www.gov.uk/government/speeches/budget-speech-2020
  2. https://decarbon8.org.uk/budget-2020-transport-we-cant-build-our-way-out-of-the-climate-challenge/ with for example: £403m for the Plug-In Car Grant; £129.5m to extend the scheme to vans, taxis and motorcycles; Vehicle Excise Duty exemption; £500m over 5 years to roll out rapid charging; removing red diesel tax relief; £304m for NOx reduction; freeze of fuel duty; £20m midlands rail hub; £5bn for new buses and cycling; £500m pothole fund; all dwarfed by the £27bn between 2020 and 2025 for road investment. Aviation is also mentioned with regards regional connectivity.
  3. https://www.theccc.org.uk/wp-content/uploads/2019/05/Net-Zero-Technical-report-CCC.pdf

ªhttps://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/871799/Budget_2020_Web_Accessible_Complete.pdf “2.95 Future Homes Standard – The government is committed to reducing emissions from homes and to helping keep household energy costs low now and in the future. In due course, the government will announce plans to improve the standards of new built homes.”

Heads or tails: achieving Net Zero by 2050 – Claire Copeland

carbon emissions, Energy Systems, Net Zero

As part of our Year 3 review of CESI research, we are re-publishing a SPRU blog written by Claire Copeland, CESI researcher on Future Energy Scenarios.

About the author:

Claire Copeland is a Research Fellow in SPRU (SPRU – Science Policy Research Unit) at the University of Sussex.

Her principal research interest is in energy futures focusing on the development of narrative scenarios for the UK and the role of energy-economy models in scenario development processes.

Contact details: claire.copeland@sussex.ac.uk Profile Details

First published on the SPRU Blog site – May 17th, 2019

Another climate report and another urgent call for action, along with a dizzying array of graphs and figures. The Committee on Climate Change (CCC), who advise the UK government on policies and planning for a low carbon economy, have produced their analysis and recommendations on how to stop UK’s contribution to global warming by 2050. This follows the “Paris Agreement” signed in December 2015 where the UK, along with 196 other countries, agreed to reduce their nation’s greenhouse gas emissions in efforts to limit global warming to 1.5°C above pre-industrial levels.

The CCC’s excellent and thorough report makes for some tough reading; not for its 277 pages and plethora of statistics and figures, but for the scale of collective effort required. The benign-sounding estimate of costs – 1-2% of GDP – disguises the extent of system change and efforts required, not only of government and businesses, but households as well.

Technological fix is not enough

For net zero emissions in the UK; industry and transport need to be completely decarbonised as well as almost entirely how we heat buildings. CCC suggests this can be achieved with electrification and hydrogen technologies, requiring deployment of four times the current level of renewables. Critically, this also depends on the deployment of carbon capture and storage (CCS), including net negative technologies such as bio-energy carbon capture and storage (BECCS), and some direct air capture (DAC) to take CO2 from the air and sequester underground. BECCS and DAC are needed because of the difficulties in decarbonising aviation and shipping.

ccs
Carbon capture and storage technology in Alberta, USA (Free image)

The UK has so far had little success in getting CCS off the ground: In 2015, the then chancellor George Osborne, said it was “too costly” and pulled the plug on £1 billion of government funding. This makes deployment of CCS at the scale required much more difficult. However, there has been recent renewed interest from the government in CCS, but this is with a smaller pot (£20 million) and with broader ambitions to include industrial decarbonisation.

Much is made in the report about progress to date and the fall in the cost of deploying renewable technologies, particularly from wind. The CCC’s estimate of costs, incredibly, is a similar size relative to GDP as they estimated for achieving the Climate Change Act 2008. However, the UK is not on track to meeting its obligations set out in 2008, and there is also no guarantee that renewables will remain low cost. Wind turbines have towers made from steel and industrial decarbonisation efforts, whether here or elsewhere, could lead to that steel becoming substantially more expensive. For example, a fossil free steel plant initiative in Sweden, predict rising global demand could result steel prices increasing 20-30%. This will impact on the cost of wind power and potentially result in questionable financial viability if deploying in places that are less favourable for wind.

wind
Rampion Wind Farm seen from the coast of Brighton. Photo by Dominic Alves shared under CC BY 2.0 license

But all these technologies will not be enough. As has been highlighted by some news articles so far, efforts to change consumer behaviour will also be needed: Flights will need to be curbed and a switch in diets away from meat, poultry, fish and dairy will be needed, impacting on UK’s livestock farmers. If consumer behaviour overall does not shift in the direction and to the extent required, then this will need to be compensated for elsewhere and could result in higher costs.

No better than the toss of a coin?

Even if CCC’s recommendations are implemented, and replicated around the world, the chances of limiting warming to 1.5°C would be over 50%. This means that the chances of success could be little better than the toss of a coin. It is curious that the CCC’s estimate of costs for action under the Climate Act 2008, used higher chances (66%) in limiting warming (to 2°C). By setting the chances of succeeding lower, CCC has reduced the costs and efforts required. Presumably so as to make this politically palatable.

This does not appear to be consistent with the Paris Agreement’s requirement for the “highest possible ambition” and there are calls for the UK to cut emissions even faster and be net zero. However reducing emissions faster, say the CCC, would be “very risky”– particularly for the UK economy that would see capital being terminated too early and scrapped.

Talking the talk, but not walking…

While UK Parliament has declared a climate emergency, recent decisions made by the UK government are at odds with halting contribution to climate change: Expansion of Heathrow with an extra 16 million long haul seats available by 2040, and overriding local concerns for shale gas development. While attempts were made to overturn the government’s Heathrow expansion decision this was not successful. Furthermore, without the deployment of CCS, there is absolutely no room for developing new natural gas reserves for UK to become a net zero emissions nation.

heathrow
Heathrow Airport runway (free image)

Where the burden of costs should fall is going to be a highly politicised issue. The CCC state clearly that the distribution of costs should not only be determined (by the government) as fair, but be perceived to be fair. No matter what the cost is in proportion to the GDP is overall – what will matter is not only the appetite, but crucially the ability, to absorb costs whether it be a particular project, business, employee, consumer, or household.

Costs of mitigating climate change became a hot topic in the recent elections in Finland. The Finns Party campaigned against those costs and resulted in coming second in the election. Given our own problems with whether or not and how to leave the EU, and the lack of understanding of (or even regard to) the financial consequences of doing so, action to mitigate climate change is likely to be a contentious issue.

While there are signs that the public mood is changing, there is no room for complacency and action is needed by each of us, since politics and technological fixes alone will not get the UK to net zero emissions. The right noises have come from UK’s politicians, but this has yet to be translated into the urgent action needed to steer our energy system and economic activity onto the right track. As individuals we also need to do our bit and be willing to change our lifestyles, before nature does this for us. Making sure this transition happens in a way that is fair and just to all is going to be critical to its success.

The role of the building engineer within the development of energy systems – Dr David Jenkins

built environment, carbon emissions, Domestic, Energy Systems

National Centre for Energy Systems Integration (CESI) Co-Investigator, Dr. David Jenkins, is a research specialist in sustainable buildings.  In this week’s blog, he discusses how buildings can be considered in future energy systems and how his CESI research is shaping this consideration.

About the Author

Dr David Jenkins is an Associate Professor in the Institute of Sustainable Building Design at Heriot-Watt University. He has over 70 publications in the area of low- energy buildings, energy policy, and climate change adaptation. He has worked on a number of EPSRC projects concerned with the energy use of the built environment, such as Tarbase,  Low Carbon Futures, ARIES and CESI and has contributed to a number of reports in these areas for UK and Scottish Governments. He is currently PI of the CEDRI project, looking to apply community energy analyses to case studies in India.

Contact details:- d.p.jenkins@hw.ac.uk  Profile Details

The built environment has always been of great importance in any discussion of carbon saving targets in the UK. 13% of UK carbon emissions emanate from heating/cooking in residential buildings alone[1]. 29% of emissions are linked to “energy supply” (including electricity supply to the built environment), with other sectors (e.g. “business” at 17% and “industrial processes” at 3%) also having energy consumption that is heavily linked to the built environment. Therefore, as we map out our future energy systems (gas/electricity grids and other energy pathways) we must have an understanding of the evolving energy demand characteristics of the diverse range of buildings that we occupy.

A practitioner with a particularly good understanding of this detail, the building engineer, often has their professional boundaries drawn around the building itself. Therefore, the sizing of a boiler, assessment of general building performance, and choices related to low-carbon design are not always placed in the context of other important factors within the energy supply chain.

Whilst this focus is to some extent defendable – the challenges of low-carbon building design are, in themselves, considerable – it does run the risk that crucial knowledge of building performance is not reflected in energy system modelling. This is particularly true when we investigate the steep vectors of change facing our energy systems in the coming decades. Coincident changes in climate, technologies, fuels, and operation, provide a landscape of uncertainty that must be consistently reflected in projections of every aspect of our energy system: supply, infrastructure/distribution, storage, and demand. For example, a future projection assuming the continued existence of an established mains gas grid for heating homes is not necessarily consistent with the installation of several million heat pumps for residential heating. The latter change should, therefore, be accompanied by an assumption on the supply-side that the gas grid will either be reduced in scale or used for something else. Policy in these different areas must also be similarly synergistic.

The building modeller is crucial to our understanding of energy demand but, with energy systems (e.g. National Grid) involving multiple actors from different disciplines, a key challenge is to provide guidance and future projections that are translated into different discipline-specific vernaculars. Integration across the disciplines must be reflected in modelling approaches, policy-making frameworks, and outputs. The CESI project, where novel modelling techniques are being used to explore the effect of future buildings on national energy systems, sees this as a key challenge in producing actionable guidance to a range of practitioners.

Another issue that often dissuades the traditional building modeller/engineer from interacting with wider energy system analysis is “scale”. Modelling a building is quite different to modelling buildings. Capturing the energy demand characteristics of a community of buildings (e.g. such as might be served by a substation) requires an understanding of the diversity of energy use. A “spikey” electrical demand profile of a single dwelling (showing kettle’s boiling and toasters toasting) is quite different to that of a 200-dwelling profile, where different behaviours and activities are summated together in a smoother profile. Likewise, asking a building engineer to consider the aggregated demand profile of, say, 200 gas boilers working at slightly different schedules is a step change from a detailed hourly profile of a single boiler. Yet this level of detail is particularly valuable when we consider what might happen to energy demand at specific times in the future. Will electric heat pumps create national electrical demand profiles that are more difficult to meet for energy suppliers? Or are such changes perfectly manageable providing storage and management solutions are utilised at the correct point in the network? And what happens if millions of people wish to home-charge their electric vehicles at similar times in the evening? What does a new residential electrical demand profile now look like for the UK? This, therefore, does not just require an understanding of scale, but also that of temporal resolution; daily averages of energy use will not indicate where and when such problems might be manifest, and what their solutions might be.

The future building engineer will be required to build on existing core skills to reflect the above context. Changes to energy supply (such as carbon intensity) will, ultimately, alter our assumptions of “good” and “bad” technologies for the built environment. Conversely, technological and behavioural change in the built environment will change our assumptions on how to supply that energy efficiently. This co-evolution of change across sectors is central to CESI and encapsulates the challenge to, but also the value of, multi-disciplinary energy system modeling.

[1] 2015 UK GREENHOUSE GAS EMISSIONS, FINAL FIGURES, 7th Feb 2017 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/604350/2015_Final_Emissions_statistics.pdf