Neil Strachan

Distributed generation and distribution utilities

Distributed (co)generation (DG) represents an alternative paradigm of energy supply and the opportunity for significant CO2 emission reductions. This paper investigates the adoption of the DG technology of internal combustion (IC) engine cogeneration in the Netherlands and UK from 1985–1998. This detailed comparison was motivated to understand why the Netherlands installed 20 times as many units and 40 times as much DG capacity (per capita) compared to the UK. The primary finding of this study emphasizes the win–win partnerships between DG adopters and utilities. While both governments promoted DG as part of their CO2 reduction goals, only distribution utilities in the Netherlands were primed to support greater DG penetration. Crucially, Netherlands utilities offered high electricity buy-back rates which enabled innovative utilization of DG. Flexible operation modes allowed investment in larger units, benefiting from economies of scale due to fixed components in maintenance costs, and extended DG use to the much larger set of sites with limited electricity base-loads. The win–win partnerships between distribution utilities and DG adopters for cost savings also facilitated improved management of the electricity network. A final consequence was a virtuous circle of maintenance cost reductions from geographic concentration of DG units, resulting in improved returns and hence more DG unit sales.

Indirect CO2 Emission Implications of Energy System Pathways: Linking IO and TIMES Models for the UK

Radical changes to current national energy systems-including energy efficiency and the decarbonization of electricity-will be required in order to meet challenging carbon emission reduction commitments. Technology explicit energy system optimization models (ESOMs) are widely used to define and assess such low-carbon pathways, but these models only account for the emissions associated with energy combustion and either do not account for or do not correctly allocate emissions arising from infrastructure, manufacturing, construction and transport associated with energy technologies and fuels. This paper addresses this shortcoming, through a hybrid approach that estimates the upstream CO2 emissions across current and future energy technologies for the UK using a multiregional environmentally extended input-output model, and explicitly models the direct and indirect CO2 emissions of energy supply and infrastructure technologies within a national ESOM (the UK TIMES model). Results indicate the large significance of nondomestic indirect emissions, particularly coming from fossil fuel imports, and finds that the marginal abatement cost of mitigating all emissions associated with UK energy supply is roughly double that of mitigating only direct emissions in 2050.

Towards a low-carbon economy: scenarios and policies for the UK

This article analyses the implications of long-term low-carbon scenarios for the UK, and against these it assesses both the current status and the required scope of the UK energy policy. The scenarios are generated using the well-established MARKAL (acronym for MARKet ALlocation) UK energy systems model, which has already been extensively used for UK policy analysis and support. The scenarios incorporate different levels of ambition for carbon reduction, ranging from 40% to 90% cuts from 1990s level by the year 2050, to shed insights into the options for achieving the UKs current legally binding target of an 80% cut by the same date. The scenarios achieve their carbon reductions through very different combinations of demand reduction (implying behaviour change) and implementation of low-carbon and energy efficiency technologies on both the supply and demand sides. In all cases, however, the costs of achieving the reductions are relatively modest. The ensuing policy analysis suggests that while the cuts are feasible both technically and economically and while a number of new policies have been introduced in order to achieve them, it is not yet clear whether these policies will deliver the required combination of both short- and long-term technology deployment, and behaviour change for the UK Governments targets to be achieved.

The role of international drivers on UK scenarios of a low-carbon society

An integrated set of low-carbon society (LCS) scenarios for the UK were analysed using the UK MARKAL Macro (M-M) model. A

Characterising the Evolution of Energy System Models Using Model Archaeology

100/tCO2 carbon price scenario was compared with long-term LCS scenarios with a domestic 80% CO2 reduction target. As M-M is a national-level model, a set of five international drivers were investigated, and grouped under Annex I consensus and Global consensus assumption sets. For economy-wide results the inclusion of international aviation and potential large-scale purchases of CO2 permits (when available) are most important. For sectoral implications, all international drivers considered here are important; for example in divergent overall size and configuration of the UK electricity sector. The carbon price scenario and set of 80% LCS targets scenarios give GDP losses rising from 0.36% to a range of 1.64–2.21% in 2050. This steep cost convexity in deep CO2 reductions represents increasing efforts to decarbonize the UK energy system, and the further impact of key international drivers. This illustrative analysis demonstrates that UK policy makers should be cognisant of, and flexible with respect to, international strategies on LCS and emission reduction targets.

Policy implications from the Low-Carbon Society (LCS) modelling project

In common with other types of complex models, energy system models have opaque structures, making it difficult to understand both changes between model versions and the extent of changes described in research papers. In this paper, we develop the principle of model archaeology as a formal method to quantitatively examine the balance and evolution of energy system models, through the ex post analysis of both model inputs and outputs using a series of metrics. These metrics help us to understand how models are developed and used and are a powerful tool for effectively targeting future model improvements. The usefulness of model archaeology is demonstrated in a case study examining the UK MARKAL model. We show how model development has been influenced by the interests of the UK government and the research projects funding model development. Despite these influences, there is clear evidence of a strategy to balance model complexity and accuracy when changes are made. We identify some important long-term trends including higher technology capital costs in subsequent model versions. Finally, we discuss how model archaeology can improve the transparency of research model studies.

Electricity and Conflict: Advantages of a Distributed System

Under the Japan—UK research project ‘Low-Carbon Society (LCS) Scenarios Towards 2050’, an international modelling comparison was undertaken by nine national teams, with a strong developing-country focus. Core model runs were a Base case, a Carbon price case (rising to

Failure to achieve stringent carbon reduction targets in a second-best policy world

100/tCO2 by 2050) and a Carbon-plus case to investigate an LCS scenario with a 50% reduction in global CO2 emissions by 2050. The comparison emphasis was to focus on individual model strengths (notably technological change, international emissions trading, non-price (sustainable development) mechanisms and behavioural change) rather than a common integrated assumption set. A complex picture of long-term LCS scenarios comes from the range of model types and geographical scale (global vs. national); however, common themes for policy makers do emerge. A core finding is that LCS scenarios are technologically feasible. However, preferred pathways require clear and early target setting and incorporation of emissions targets across all economic activities. This will probably entail significant socio-economic changes. To realize major LCS transitions requires sustained progress in R&D and deployment of a broad range of technologies, with carbon capture and storage (CCS) a key technology in most low-carbon portfolios. Developing countries, in particular, face an immense challenge to achieve LCS in light of their economic growth requirements. As such, international cooperation is required in iterative and flexible burden sharing under international emissions trading regimes.

Realising transition pathways for a more electric, low-carbon energy system in the United Kingdom: Challenges, insights and opportunities

With recent events having highlighted the need to consider deliberate attacks when planning electric power systems, it is pertinent to make a quantitative comparison of an electricity system based on distributed natural-gas-fired units to a traditional system based on large centralized plant. The distributed system proves to be up to five times less sensitive to measures of systematic attack.

National climate policy implications of mitigating embodied energy system emissions

Legislation to decarbonise energy systems within overall greenhouse gas reduction targets represents an immense and unprecedented energy policy challenge. However there is a dichotomy between this level of policy ambition and prior modelling studies that find such targets economically, technologically and socially feasible under idealised ―first-best policies. This paper makes a significant contribution to current analytical efforts to account for realistic ―second-best climate mitigation policy implementation. This is achieved via a technical classification of secondbest common mode issues at a detailed national level: both internal (behavioural change, infrastructure implementation) and external (new technologies, resource availability). Under a combinatory second-best scenario, meeting targets greater than a 70% reduction in CO2 by 2050 entail costs above a subjective barrier of 1% of GDP, while extreme mitigation scenarios (>90% CO2 reduction) are infeasible. These high costs are equally due to disappointing progress in behavioural and technological mitigation efforts. Expensive second-best mitigation scenarios can still rely on extreme assumptions including the full deployment of the UK‘s offshore wind resource or the complete diffusion of energy efficiency measures in end-use sectors. By demonstrating the fragilities of a low carbon energy system pathway, policy makers can explore protective and proactive strategies to ensure targets can actually be met. Additionally, systematic analysis of failure in stringent long term decarbonisation scenarios teaches energy analysts about the trade-offs in model efficacy vs. confidence.