Climate Change Plan: third report on proposals and policies - written statement

TIMES Modelling

Environment, Climate Change and Land Reform Committee

1. The Committee recommended that an independent assessment of the use of the TIMES Model in a Scottish context be commissioned following the publication of the final Plan and the results should form part of the development of the next report on policies and proposals. (217)

• We remain committed to releasing the Scottish TIMES model. We will work towards releasing the model for the academic community to further research into whole system energy and climate change modelling; and maintain our commitment to transparency

2. The Committee recommended that the Scottish Government publish the audits (the inputs, constraints, assumptions and results) of each TIMES Model run in full, including the data used to ascertain the cost to the system of removing carbon capture and storage (CCS), in the final Plan. (262)

Further details around the underlying assumptions, inputs, constraints applied and results by sector are included in the technical annex of the Plan.

• Scottish Government policies support the development of Carbon Capture and Storage, which will be important for the long term cost-effective decarbonisation of our economy in key sectors such as heat, industry and electricity. In response to feedback on the draft Plan and Energy Strategy, we have revised our assumptions about the application of CCS. The feedback we received highlighted the challenge of deploying CCS at scale in the period set out in the draft. As a result of this, we have applied a constraint in the model, limiting the uptake of CCS before 2030. Given the feedback on the interaction with bioenergy, we have also limited the ability to account for negative emissions in the modelling, through bioenergy generation with CCS. CCS is not required for the delivery of the electricity generation carbon envelope out to 2032. Scottish Government policies continue to support the development of CCS, which will be important for the long term cost-effective decarbonisation of our economy in key sectors such as heat, industry and electricity.

3. The Committee recommended that a run of the TIMES Model is produced to supplement the final Plan which emphasises alternative car traffic growth assumptions and greater emphasis on modal shift. (316)

• The Element Energy report: "Greenhouse Gas Emissions Reduction Potential in the Scottish Transport Sector From Recent Advances in Transport Fuels and Fuel Technologies", commissioned by Transport Scotland and published in January 2017, sets out different scenarios on the impact of reducing demand growth. Our view is that the measures set out in the final Plan mean that we do not require additional demand reduction measures to meet the emissions reduction envelope.

4. The Committee proposed that the final Plan include detail of how the TIMES Model will be used in the monitoring and evaluation of the progress being made towards Scotland's goals for greenhouse gas emissions reductions, including any proposed stakeholder involvement in the use of the Model. (533)

• TIMES is a high-level strategic model used to identify a potential pathway for achieving our climate change targets and meeting our energy demands over a specified time horizon. To report on actual emissions savings achieved over time we will use the Greenhouse Gas Inventory and other sector data sources.
• In terms of stakeholder involvement in the use of the model, we continue to develop the model and seconded our lead TIMES analyst to the Edinburgh Centre for Carbon Innovation to work with academics to refine and improve the model, embed understanding of it, and draw in sector expertise.
• We remain committed to releasing the Scottish TIMES model. We will work towards releasing the model for the academic community to further research into whole system energy and climate change modelling; and maintain our commitment to transparency

5. The Committee recommended that the Scottish Government include details of the analysis (where it is available) undertaken of alternative modelling approaches (including the framework in place for RPP1 and 2 and the system used by the Committee on Climate Change), showing the advantages and disadvantages of each, and demonstrate the justification for choosing the TIMES Model in the final Plan. (126)

• The Scottish TIMES model is a high level strategic model, covering the entire Scottish energy system and containing many thousands of variables covering existing and future technologies and processes. The development of the TIMES modelling framework is co-ordinated by the International Energy Agency. It is rapidly becoming the de-facto standard tool for whole-systems energy modelling in Europe and North America. The Scottish model was built by an international consortium of experts from E4TECH, E4SMA, KANORS, SYSTRA and Imperial College London. We are grateful for the advice and assistance provided by the analytical team in the UK Department for Business, Energy and Industrial Strategy. The Scottish Government has been keen to ensure compatibility with the UK Government's approach.
• The model combines two different, and complementary, approaches to modelling energy: a technical engineering approach and an economic approach. The model uses this information to identify the carbon cost-effectiveness of different technologies, fuels and other carbon reduction measures, in order to provide a consistent comparison of the costs of action across all sectors.
• We continue to use sector models to complement and strengthen the overall analysis for the Plan. Sector models provide more detail on the individual sectors than is possible within the TIMES framework. We have made adjustments to the TIMES model to take into account this sector-specific analysis.
• For the first two Reports on Proposals and Policies we did not have access to a whole-system energy model. As a result we estimated a top down 'business as usual' (BAU) set of emissions for each year of the RPP, for each sector. We then netted off the estimated impact of policies and proposals to ensure our net emissions in each year were in line with the targets.
• The key constraint with the approach in previous RPPs was that, while sectors could individually identify where they could best reduce emissions, they couldn't see how the costs of their efforts compared on a consistent basis with other sectors nor what the wider system impacts might be of the total package of policies and proposals.

6. The Committee recommended that all sectors, policies and proposals are consistently considered within the same model framework and the detail on the development of these be equally extensive. The Committee recommended that the extent to which the TIMES Model and related external models were used for each sector is made clear in the final Plan. (177, 179, 146, 216)

• Outputs are grouped into eight sectors in Scottish TIMES. These are: Residential and Services, combined into a new Buildings chapter; Industry; Electricity; Transport; Waste; Agriculture; and Land Use, Land Use Change and Forestry (LULUCF). For the demand driven sectors (Residential, Services, Industry, Transport, and heat and transport within the Agriculture sector), the model must meet the defined final energy demands. In the Electricity sector, demand is determined by the model and is driven by demand for electricity as a fuel in the other sectors (through the electrification of transport or heating demand).
• Scottish TIMES also incorporates non-energy sectors (most of Agriculture, Waste and LULUCF, including peatland). Although these non-energy sectors, for the most part, do not have final energy demands nor long potential supply chains, the model incorporates emissions projections for each, informed by sector analysis and models. This is a standard approach used to address non-energy components of whole system models and ensures that once the climate change targets are taken into account, emissions from energy sectors are not allowed to increase beyond the overall targets.
• The Transport sector is incorporated into TIMES via fuel shares and emissions projections. While both are determined exogenously, changes to Transport fuel shares will ripple through the rest of the system, as Transport supply chains are fully incorporated into the model. Transport emissions projections are taken into account in deriving sector envelopes in the same way as for the non-energy sectors; their inclusion ensures total emissions from all sectors do not exceed the overall targets. The emission projections and fuel shares for Transport in the draft Plan were based on data provided by Transport Scotland and sourced from research by Element Energy. The Element Energy report , commissioned by Transport Scotland and published in January 2017, sets out potential pathways for emissions reductions in the Transport Sector. The Element Energy report allowed the Scottish Government to utilise more granular data in considering its emissions reduction strategy. The transport sector emissions profile in the Plan has been updated to account for the impact of Programme for Government 2017- 2018 announcements on low emission zones and electric vehicles.
• By ensuring that emissions trajectories for all sectors are informed by sector-specific models and analysis, we can be confident of the robustness of sector emissions envelopes. Further detail on the input assumptions, approach and results by sector is provided in the technical annex of the Plan.

7. The Committee recommended that the final Plan include information on plans to allow stakeholders, including the Committee on Climate Change, access to iterations of the TIMES Model to allow them to run scenarios through the framework. (99)

• We remain committed to releasing the Scottish TIMES model. We will work towards releasing the model for the academic community to further research into whole system energy and climate change modelling; and maintain our commitment to transparency

Employment, Jobs and Fair Work Committee

1. The Committee commended the whole-system approach but noted that it should not be at the expense of the detail provided in the earlier Reports on Proposals and Policies. The Committee noted that the TIMES model relies on certain assumptions. However, the Committee does not know exactly what information was incorporated into the model and what weight was given to practical considerations on delivery, costs and disruption. The Committee noted that it believes that this approach lacks transparency. ( EJFW 15)

• Further details around the underlying assumptions, modelling approach taken and results by sector is included in the technical annex of the Plan.

Environment, Climate Change and Land Reform Committee & Rural Economy and Connectivity Committee

1. The committees recommended that each policy outcome, policy and proposal in the Plan should contain information on the emissions reductions in MtCO₂e they are expected to achieve. (ECCLR 255, REC 19)

• The TIMES model does not work on the basis of deducting abatement from projected emissions; instead, it identifies the most efficient parts of the system to remove greenhouse gas emissions and allocates sector envelopes accordingly. Policies and proposals are then developed to ensure emissions remain within the envelope limits.
• The consequence of employing TIMES is that it does not present annual emissions abatement for individual policies and proposals as was the case in the two previous reports on proposals and policies. There is no counterfactual from which to deduct abatement.
• In addition to the absence of sector business as usual projections, attributing abatement to any one sector is problematic when considering the whole energy system. TIMES tells us the amount by which emissions need to fall over time to meet our targets and while it does produce suggested sector envelopes for meeting these targets, these cannot necessarily be translated into abatement by sector. For instance, does a reduction in electricity demand in one sector equate to abatement for that sector or for the electricity generation sector? Similarly, does an increase in electric vehicles result in emissions abatement from transport, an increase in demand from the generation sector or a reduction in emissions from refineries? TIMES addresses this challenge by taking a system-wide view.