Iain Staffell | Imperial College London (original) (raw)

Papers by Iain Staffell

Sustainable Production and Consumption, 2024

The role of carbon dioxide removal (CDR) is undoubtedly crucial in achieving the climate goals an... more The role of carbon dioxide removal (CDR) is undoubtedly crucial in achieving the climate goals and end-of-century global warming target. Given its role as a leader in global climate actions, the European Union (EU) is expected to take a leading role in CDR developments: yet there is a lack of depth in the region’s CDR strategy and deployment. A comprehensive CDR approach based on integrated assessment modelling for the EU is important to give valuable insights into optimal CDR-based mitigation pathways regarding scalability, technology readiness, trade-offs with the Earth system, and deployment strategies. Here, we have used the GCAM-CDR v1.0 to model a diverse novel CDR portfolio of bioenergy carbon capture and storage (BECCS), direct air capture and carbon storage (DACCS), terrestrial enhanced weathering (TEW), and ocean-enhanced weathering (OEW) in a mid-century carbon neutrality target. We find that CO2 removal by BECCS scales quickly to gigatonnes of CO2 removal by mid-century, and DACCS is a latter-century mitigation technology in the EU’s emission mitigation pathway. TEW will play a crucial role in achieving carbon neutrality in the EU if this climate goal is advanced by a decade. Modelled results show that achieving carbon neutrality through diverse CDR relies heavily on significant emission reductions in the industrial and hard-to-abate sectors. Finally, we observed that nuclear power will be an important energy resource for the energy-consuming CDR technologies in Europe. This study recommends that the EU carbon removal structure should not be limited to DACCS, but rather allow for innovations in carbon removal technologies.

Current Research in Environmental Sustainability, 2024

The climate impact of food is rapidly gaining attention. Studies focus on global and national imp... more The climate impact of food is rapidly gaining attention. Studies focus on global and national impacts, marginalising the role and preferences of individual consumers. Diet is highly personal and for changes to be widely adopted they should be consistent with peoples’ lifestyles, preferences, tastes, and knowledge. We construct global scenarios of reducing meat consumption and model their carbon mitigation potential to 2050. We conduct a simple survey to explore UK consumers’ preferences for different approaches to reducing meat consumption, which are used to develop scenarios, and units for communicating the associated portion sizes and emissions savings. Results from our survey suggest that modest reductions in meat consumption are more resonant (e.g., eating three portions per week) rather than absolutes (becoming vegan for one month) or abstractions (consuming 170 cal of meat per day). Similarly, tangible analogies such as number of airline flights are preferred over raw emissions abated. We find that reducing meat intake to recommended healthy levels (92 cal per day) and avoiding ruminant meat could almost halve production-phase GHG emissions from the food system. Our survey illustrates how such information can be rephrased for more engaging communication: “reducing your meat intake to three times per week is equivalent to avoiding six short-haul return flights each year”.

Journal of Cleaner Production, 2024

The decarbonisation of industry, heating and transportation is a major challenge for many countri... more The decarbonisation of industry, heating and transportation is a major challenge for many countries’ energy transition. Hydrogen is a direct low-carbon fuel alternative to natural gas offering a higher flexibility in the range of possible applications, yet currently most hydrogen is produced using carbon-intensive steam methane reforming due to cost considerations. Therefore, this study explores the economics of a prominent low-carbon method of hydrogen production, comparing the cost of hydrogen generation from offshore wind farms with and without grid electricity imports to conventional hydrogen production methods. A novel techno-economic model for offshore electrolysis production costs is presented, which makes hydrogen production fully dispatchable, leveraging geological salt-cavern storage. This model determines the lifetime costs aportioned across the system components, as well as the Levelised Cost of Hydrogen (LCOH). Using the United Kingdom as a case study, LCOH from offshore wind power is calculated to be € 8.68/kgH2
using proton exchange membrane electrolysis (PEMEL), and € 10.49/kgH2 using alkaline electrolysis (AEL), € 10.88/kgH2 with grid electricity to backup the offshore wind power. A stochastic Monte-Carlo model is used to asses the uncertainty on costs and identify the cost of capital, electrolyser and wind farm capital costs, and cost of electricity as the most important drivers of LCOH across the different scenarios. Reducing the capital cost to comparative levels observed on today’s wind farms alone, could see AEL LCOH fall to € 5.32/kgH2, near competitive with conventional generation methods.

Energy Economics, 2024

Electricity system models are widely used to study future designs of power markets. They are comm... more Electricity system models are widely used to study future designs of power markets. They are commonly used to represent electricity dispatch decisions but struggle to reproduce realistic variation in prices. We show that current assumption of generators bidding their average variable cost (AVC) underestimates the spread and volatility of hourly wholesale prices.While existing models can accurately estimate the revenues of conventional (thermal) generators, they fail with the revenues of next-generation technologies such as storage and merchant transmission. Imperfect competition makes market prices differ from the theoretical optimum. In this paper we present a bottom-up electricity market model for Europe called EuroMod: a deterministic linear optimization in GAMS which models generation, storage and transmission dispatch at hourly resolution for European markets connected using net transfer capacities. Two additions are tested for their ability to improve wholesale price formation: a simple modification to the short-run marginal cost approach that allows generators to make bids which diverge from AVC; and a post-optimizer transformation of prices with respect to demand net of renewables. These corrections improve both the representation of prices and dispatch decisions across European markets, and reduce errors by 40% for prices, 6% for power station revenues, between 24% to 33% for energy storage profits, and 43% for the median arbitrage value of interconnectors when compared to traditional linear models.

Renewable and Sustainable Energy Reviews, 2025

The global expansion of solar photovoltaics (PV) is central to the global energy transition. As g... more The global expansion of solar photovoltaics (PV) is central to the global energy transition. As governments aim to triple renewable energy capacity by 2030, solar PV is poised for rapid growth, particularly outside mid-latitude regions (China, Europe, US) where uptake has been highest. These new growth areas have diverse environmental conditions, where factors like higher temperatures and aerosol concentrations strongly impact solar power production. A comprehensive review of these effects therefore aids PV performance and siting optimization. This review examines six key influences: solar irradiance, ambient temperature, atmospheric conditions, terrain effects, extreme weather events, and long-term irradiance changes. First, solar irradiance has strong geographic and temporal variability, making it the most significant factor. Second, raising module temperature reduces efficiency by 0.4–0.5 % per degree Celsius, limiting productivity in hotter climates. Third, atmospheric conditions (clouds, aerosols, pollutants, and dust) can reduce electricity output by up to 60 %, especially in desert regions. Fourth, terrain factors like albedo and snow present mixed effects, with increased reflection boosting output but snow obstructing panels. Fifth, extreme weather like wildfires and hailstorms cause substantial damage, while solar eclipses lead to large but short-lived output losses. Finally, long-term changes in solar irradiance, driven by climate change and air pollutants, present future challenges for maintaining PV efficiency. Optimizing PV systems for diverse climates and mitigating environmental impacts on productivity is important to the continued success of solar photovoltaics. This review highlights the need for tailored strategies to maintain performance in varied and evolving environmental contexts.

Energy, 2024

Climate change and geopolitical risks call for the rapid transformation of electricity systems wo... more Climate change and geopolitical risks call for the rapid transformation of electricity systems worldwide, with Europe at the forefront. Wind and solar are the lowest cost, lowest risk, and cleanest energy sources, but their variability poses integration challenges. Combining both technologies and integrating regions with dissimilar generation patterns optimizes the trade-off between maximizing energy output and minimizing its variability, which respectively give the lowest levelized cost and lowest integration cost. We apply the Markowitz mean-variance framework to a rich multi-decade dataset of wind and solar productivity to quantify the potential benefits of spatially integration of renewables across European countries at hourly, daily and monthly timescales. We find that optimal cross-country coordination of wind and solar capacities across Europe’s integrated electricity system increases capacity factor by 22% while reducing hourly variability by 26%. We show limited benefits to solar integration due to consistent output profiles across Europe. Greater wind integration yields larger benefits due to the diversity of regional weather patterns. This framework shows the importance of considering renewable projects not in isolation, but as interconnected parts of a pan-continental system. Our results can guide policymakers towards strategic energy plans that reduce system-wide costs of renewable electricity, accelerating the clean energy transition.

Nature Climate Change, 2023

The transition towards a low-carbon power system presents challenges and opportunities for the w... more The transition towards a low-carbon power system presents challenges
and opportunities for the workforce with important implications for just
transitions. Studies of these distributional labour impacts could benefit
from tighter linkages between energy and employment modelling. Here, we
couple a power-sector optimization model, an employment impact model
and demographic databases to understand state-level job characteristics
and the societal implications of low-carbon transitions in the US. Although
decarbonization brings consistent job growth, it heightens the need for
investment in human capital and supply chain restructuring. Major fossil
fuel-producing states need to prepare for fewer mining jobs under the US
Long-Term Strategy, so other opportunities should be created or seized.
The lowest-skilled workers will experience more uncertain employment
outcomes. Expanding renewable energy could improve opportunities
for women in fossil fuel-dependent states, but not enough to disrupt
the national gender status quo. This work provides a new quantitative
perspective to inform proactive just transition policies.

Transportation Research Part D, 2023

The rapid uptake of new vehicle technologies will change the environmental impact of road transpo... more The rapid uptake of new vehicle technologies will change the environmental impact of road transport. The emissions produced in power plants supplying electric vehicles (EVs) and vehicular non-exhaust PM 2.5 emissions leaves the benefits of EVs unclear. We develop a fleet turnover model to assess how different vehicle technologies, the rate of technological change, and changing transport demand impact vehicle and power station CO 2eq and air pollutant emissions. By 2050, the transition to EVs reduces yearly CO 2eq emissions by 98% and cumulative CO 2eq emissions by over 50%; accelerating or delaying EV uptake by 5 years changes these results by 1% and 17%, respectively. By 2050, EVs reduce annual NO x emissions by 97%, but have little impact on PM 2.5 due to vehicular non-exhaust emissions. Accelerating or delaying EV uptake had little impact on air pollution emissions. Reducing vehicle kilometres has the potential to reduce nonexhaust PM 2.5 emissions by 20% in the long-term.

Energy Strategy Reviews, 2023

Most publicly available wind data are aggregated to a temporal resolution of 30 or 60 min. This i... more Most publicly available wind data are aggregated to a temporal resolution of 30 or 60 min. This is adequate for some purposes, such as large-scale wind integration studies. However, the consequent loss of high-frequency power fluctuations from the data can significantly impact analysis on local and regional scales. The importance of this missing variability to the accurate assessment of renewables integration is increasingly being recognised as wind power is considered for energy autarky and local energy systems. Here, we investigate the statistics of the lost variability using two high-temporal-resolution datasets from France and the US. In particular, we focus on the likelihood that minimum and maximum thresholds are exceeded and illustrate the importance of sub-half-hourly variability for assessing sector-coupling applications, such as wind farmelectrolyser systems. We find that using half-hourly averaged turbine data can underestimate the occurrence of zero power by a factor of two. This matters if a wind turbine is coupled to an electrolyser, either directly or with only short-duration storage, because of dynamic operating constraints. The lower output limit means that half-hourly wind output could overestimate the hydrogen production and energy storage capabilities of alkaline electrolysers by up to 70 %.

Energy Reports, 2023

The EU energy and climate policy revolves around enhancing energy security and affordability, whi... more The EU energy and climate policy revolves around enhancing energy security and affordability, while reducing the environmental impacts of energy use. The European energy transition has been at the centre of debate following the post-pandemic surge in power prices in 2021 and the energy crisis following the 2022 Russia-Ukraine war. Understanding the extent to which electricity prices depend on fossil fuel prices (specifically natural gas) is key to guiding the future of energy policy in Europe. To this end, we quantify the role of fossilfuelled vs. low-carbon electricity generation in setting wholesale electricity prices in each EU-27 country plus Great Britain (GB) and Norway during 2015-2021. We apply econometric analysis and use sub/hourly power system data to estimate the marginal share of each electricity generation type. The results show that fossil fuelbased power plants set electricity prices in Europe at approximately 58% of the time (natural gas 39%) while generating only 34% of electricity (natural gas 18%) a year. The energy transition has made natural gas the main electricity price setter in Europe, with gas determining electricity prices for more than 80% of the hours in 2021 in several countries such as Belgium, GB, Greece, Italy, and the Netherlands. Hence, Europe's electricity markets are highly exposed to the geopolitical risk of gas supply and natural gas price volatility, and the economic risk of currency exchange.

Energy Research & Social Science, 2023

Mitigating climate change requires an urgent transition of the oil and gas industry. We develop t... more Mitigating climate change requires an urgent transition of the oil and gas industry. We develop two typologies of the corporate strategy and diversification options for international oil companies (IOCs) in the sustainable energy transition. Data from semi-structured interviews with oil industry professionals are thematically analysed and considered in the context of the wider literature. The resulting framework of corporate strategy options is more comprehensive than has been previously published. We find gaps in the companies' strategic readiness for the energy transition, especially in preparing for the ramp-down of the fossil fuel-based core business. Diversification options are evaluated in terms of the fit between different strategies and companies' capabilities. Many diversification options fit at least some of the existing capabilities of oil majors, but while there is potential for the companies to contribute positively to the energy transition, the current scale of change remains inadequate for meeting global climate goals. The strategic dilemma that the energy transition creates for IOCs is an essentially existential one. Future research should investigate whether IOCs can and should play an active part in the sustainable energy transition and how to drive the necessary action.

Nature Energy, 2023

Accurate modelling of the weather’s temporal and spatial impacts on building energy demand is cri... more Accurate modelling of the weather’s temporal and spatial impacts on building energy demand is critical to decarbonizing energy systems. Here we introduce a customizable model for hourly heating and cooling demand applicable globally at all spatial scales. We validate against demand from ~5,000 buildings and 43 regions across four continents. The model requires limited data inputs and shows better agreement with measured demand than existing models. We use it first to demonstrate that a 1 °C reduction in thermostat settings across all buildings could reduce Europe’s gas consumption by 240 TWh yr−1, approximately one-sixth of historical imports from Russia. Second, we show that service demand for cooling is increasing by up to 5% per year in some regions due to climate change, and 5 billion people experience >100 additional cooling degree days per year when compared with a generation ago. The model and underlying data are freely accessible to promote further research.

Energy Research & Social Science, 2023

International oil companies (IOCs) are facing mounting pressure to transition towards low-carbon ... more International oil companies (IOCs) are facing mounting pressure to transition towards low-carbon business models in line with the Paris Agreement's goals to limit global warming. Shareholder activism in oil and gas companies has increased rapidly over the past decade but has not yet been widely researched. This study explores company communication strategies within the context of climate and transition-related shareholder activism at IOC annual general meetings (AGMs). We analyse 123 relevant proxy statements produced by ExxonMobil, Chevron, and BP at their AGMs from 2006 to 2022. This yielded 10 distinct categories of resolution request, and seven common themes of communicative strategy deployed by IOCs. IOCs were generally successful at minimising the impact of climate-related and environmental shareholder activism, with most resolutions unsuccessful, and even successful ones having limited impact on company performance. However, recent shareholder revolts reveal the oil and gas (O&G) sector is experiencing more instances of, and more successful, investor pressure to improve environmental performance. Cases of voluntary changes in company policy and behaviour further indicate the potential for shareholder activism to influence low-carbon transitions. Further research of the phenomenon itself to gain greater understanding of IOC response strategies can yield insights into the nature and likelihood of a transition away from fossil fuels in the future.

Atmospheric Environment: X, 2023

Methane emissions from natural gas production are of increasing importance as they threaten effor... more Methane emissions from natural gas production are of increasing importance as they threaten efforts to mitigate climate change. Current inventory estimates carry high uncertainties due to difficulties in measuring emission sources across large regions. Satellite measurements of atmospheric methane could provide new understanding of emissions. This paper provides insight into the effectiveness of using satellite data to inform and improve methane inventories for natural gas activities. TROPOMI data are used to quantify methane emissions from natural gas within the Montney basin region of Canada and results are compared with existing inventories. Emissions estimated using TROPOMI data were 2.6 ± 2.2 kt/day which is 7.4 ± 6.4 times the inventory estimates. Pixels (7 by 7 km) that contained gas facilities had on average 11 ppb more methane than the background. 7.4% of pixels containing gas sites displayed consistently high methane levels that were not reflected in the inventory. The satellite data were not sufficiently granular to correlate with inventories on a facility scale. This illustrates the spatial limitations of using satellite data to corroborate bottom-up inventories.

Energy Research and Social Science, 2022

The operating model of the global oil industry is not compatible with the goals of the Paris Agre... more The operating model of the global oil industry is not compatible with the goals of the Paris Agreement. For the industry, there is a fundamental tension between two competing mandates: the pressure to contribute to the social goal of climate change mitigation, and the need to perform financially and meet obligations to shareholders in activities that directly contribute to climate change. To explore the range of responses to the tension, we interview professionals from large international oil companies who work or have worked in climate related roles. This is novel data from a professional group that has not previously been interviewed in depth about climate change. We develop a framework of six archetypical responses to tension within the oil industry. Examples of strategic responses include accepting the paradox to choose priorities other than climate change mitigation and confronting the paradox to demand changes to the way the oil industry operates. Examples of defensive responses include the transfer of responsibility and projection of tension to other stakeholders. Responses calling for change in the oil industry are the most common among people who have left the industry and the least common for participants from companies headquartered outside of Europe. In a field marked by controversies and value-based debates, a better understanding of the views of people working on the energy transition inside the oil industry provides new insight into the discussion about possible routes to the sustainability transition.

Transportation Research Part D, 2022

Understanding how to best integrate electric vehicles (EVs) into electricity systems is key to th... more Understanding how to best integrate electric vehicles (EVs) into electricity systems is key to the success of both sectors. We pair national-scale EV charging data with high resolution electricity generation data for the UK to calculate the average and marginal emissions produced through charging EVs. Considering the average generation mix weighted by when charging occurs, a typical Battery EV (BEV) emitted 41 g CO 2 , 27 mg NO x and 0.7 mg PM 2.5 per kilometre in 2019. A static analysis using annual averages underestimates these values by 4 %. The 'marginal' emissions from BEV charging are 25 % higher than average emissions for CO 2 and NO x , and 50 % lower for PM 2.5. Smart charging was found to reduce average CO 2 emissions by 10 % when compared to the typically charged vehicle; however, smart charging strategies may increase marginal emissions. Future smart charging strategies should minimise marginal emissions and will require access to 24-hour opportunistic smart charging.

Energy Research & Social Science, 2022

To achieve the European Union's target for climate neutrality by 2050 reduced energy demand will ... more To achieve the European Union's target for climate neutrality by 2050 reduced energy demand will make the transition process faster and cheaper. The role of policies that support energy efficiency measures and demandside management practices will be critical and to ensure that energy demand models are relevant to policymakers and other end-users, understanding how to further improve the models and whether they are tailored to user needs to support efficient decision-making processes is crucial. So far though, no scientific studies have examined the key user needs for energy demand modelling in the context of the climate neutrality targets. In this article we address this gap using a multi-method approach based on empirical and desk research. Through survey and stakeholder meetings and workshops we identify user needs of different stakeholder groups, and we highlight the direction in which energy demand models need to be improved to be relevant to their users. Through a detailed review of existing energy demand models, we provide a full understanding of the key characteristics and capabilities of existing tools, and we identify their limitations and gaps. Our findings show that classical demandrelated questions remain important to model users, while most of the existing models can answer these questions. Furthermore, we show that some of the user needs related to sectoral demand modelling, dictated by the latest policy developments, are under-researched and are not addressed by existing tools.

Chem Soc Rev, 2022

Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally ben... more Replacing fossil fuels with energy sources and carriers that are sustainable, environmentally benign, and affordable is amongst the most pressing challenges for future socioeconomic development. To that goal, hydrogen is presumed to be the most promising energy carrier. Electrocatalytic water splitting, if driven by green electricity, would provide hydrogen with minimal CO 2 footprint. The viability of water electrolysis still hinges on the availability of durable earth-abundant electrocatalyst materials and the overall process efficiency. This review spans from the fundamentals of electrocatalytically initiated water splitting to the very latest scientific findings from university and institutional research, also covering specifications and special features of the current industrial processes and those processes currently being tested in large-scale applications. Recently developed strategies are described for the optimisation and discovery of active and durable materials for electrodes that ever-increasingly harness firstprinciples calculations and machine learning. In addition, a technoeconomic analysis of water electrolysis is included that allows an assessment of the extent to which a large-scale implementation of water splitting can help to combat climate change. This review article is intended to cross-pollinate and strengthen efforts from fundamental understanding to technical implementation and to improve the 'junctions' between the field's physical chemists, materials scientists and engineers, as well as stimulate much-needed exchange among these groups on challenges encountered in the different domains.

Energy Policy, 2022

Offshore wind energy is rapidly expanding, facilitated largely through auctions run by government... more Offshore wind energy is rapidly expanding, facilitated largely through auctions run by governments. We provide a detailed quantified overview of utilised auction schemes, including geographical spread, volumes, results, and design specifications. Our comprehensive global dataset reveals heterogeneous designs. Although most auction designs provide some form of revenue stabilisation, their specific instrument choices vary and include feed-in tariffs, one-sided and two-sided contracts for difference, mandated power purchase agreements, and mandated renewable energy certificates. We review the schemes used in all eight major offshore wind jurisdictions across Europe, Asia, and North America and evaluate bids in their jurisdictional context. We analyse cost competitiveness, likelihood of timely construction, occurrence of strategic bidding, and identify jurisdictional aspects that might have influenced auction results. We find that auctions are embedded within their respective regulatory and market design context, and are remarkably diverse, though with regional similarities. Auctions in each jurisdiction have evolved and tend to become more exposed to market price risks over time. Less mature markets are more prone to make use of lower-risk designs. Still, some form of revenue stabilisation is employed for all auctioned offshore wind energy farms analysed here, regardless of the specific policy choices. Our data confirm a coincidence of declining costs and growing diffusion of auction regimes.

Advances in Applied Energy, 2022

Europe's offshore wind capacity is increasing rapidly, with larger turbines installed further fro... more Europe's offshore wind capacity is increasing rapidly, with larger turbines installed further from shore. TenneT proposed an innovative concept, the North Sea Wind Power Hub, in which several farms are connected to an artificial island which has interconnection to surrounding countries. This aims to reduce overall costs, but studies have so far evaluated hypothetical designs rather than the specific system operators' proposal, and focused primarily on construction costs rather than ongoing system-wide impacts. Here we develop a bottom-up capital cost estimate to compare the Power Hub with conventional point-to-point connection for offshore wind farms. We quantify its consequential impacts on regional electricity prices, the value of wind generation, fossil fuel generation and carbon emissions in 2030 using a pan-European electricity market model. We find that the Power Hub is cheaper if more than 10 GW of wind is built, as the avoided cost of multiple converter platforms offsets the cost of building an artificial island. It has profound impacts on electricity markets across Europe, especially in Britain and Ireland if they gain more interconnection to continental Europe. This impacts the economic viability of wind and gas power stations particularly, and saves 10Mt CO 2 per year through reduced curtailment.

Sustainable Production and Consumption, 2024

Current Research in Environmental Sustainability, 2024

Journal of Cleaner Production, 2024

Energy Economics, 2024

Renewable and Sustainable Energy Reviews, 2025

Energy, 2024

Nature Climate Change, 2023

Transportation Research Part D, 2023

Energy Strategy Reviews, 2023

Energy Reports, 2023

Energy Research & Social Science, 2023

Nature Energy, 2023

Energy Research & Social Science, 2023

Atmospheric Environment: X, 2023

Energy Research and Social Science, 2022

Transportation Research Part D, 2022

Energy Research & Social Science, 2022

Chem Soc Rev, 2022

Energy Policy, 2022

Advances in Applied Energy, 2022

Brett, DJL and Manage, M and Agante, E and Brandon, NP and Brightman, ER and Brown, RJC and Staff... more Brett, DJL and Manage, M and Agante, E and Brandon, NP and Brightman, ER and Brown, RJC and Staffell, I (2012) Fuels and fuel processing for low temperature fuel cells. In: Hartnig, and Roth,,(eds.) Polymer electrolyte membrane and direct methanol fuel cell technology: Fundamentals and performance of low temperature fuel cells (Volume 1). Woodhead Publishing

Small and micro combined heat and power (CHP) systems: Advanced design, performance, materials and applications, 2011

This chapter presents a more in-depth consideration of the opportunities and challenges associate... more This chapter presents a more in-depth consideration of the opportunities and challenges associated with distributed energy resources. Specifically, it examines very small-scale energy generation, that of residential micro-generation and associated technologies, which could in the future form part of a much more active, integrated and ultimately valuable demand-side.

Presentation given at the Energy Systems Conference in London, 2016.