Decarbonised polygeneration from fossil and biomass resources

Utilisation of biomass resources and CO2 abatement systems in currently exploited fossil resource based energy systems are the key strategies in resolving energy sustainability issue and combating against global climate change. These strategies are affected by high energy penalty and high investment. Therefore, it is imperative to assess the viability of these energy systems and further identify niche problem areas associated with energy efficiency and economic performance improvement. The current research work has two parts. The first part presents techno-economic investigation of thermochemical conversion of biomass into the production of fuels (Fischer-Tropsch liquid or methanol) and electricity. The work encompasses centralised bio-oil integrated gasification plant, assuming that the bio-oil is supplied from distributed pyrolysis plant. Bio-oil is a high energy density liquid derived from biomass fast pyrolysis process, providing advantages in transport and storage. Various bio-oil based integrated gasification system configurations were studied. The configurations were varied based on oxygen supply units, once-through and full conversion configurations and a range of capacities from small to large scale. The second part of this thesis considers integration of various CO2 abatement strategies in coal integrated gasification systems. The CO2 abatement strategies under consideration include CO2 capture and storage, CO2 capture and reuse as well as CO2 reuse from flue gas. These facilities are integrated into cogeneration or polygeneration systems. The cogeneration concept refers to the production of combined heat and power while polygeneration concept is an integrated system converting one or more feedstocks into three or more products. Polygeneration is advocated in this work attributed to its high efficiency and lower emission. Furthermore, it can generate a balanced set of products consisting of fuels, electricity and chemicals. It is regarded as a promising way of addressing the future rapidly growing energy demands. A holistic approach using systematic analytical frameworks comprising simulation modelling, process integration and economic analysis has been developed and adopted consistently throughout the study for the techno-economic performance evaluation of decarbonised fossil and bio-oil based systems. Important design methodology, sensitivity analysis of process parameters and process system modifications are proposed. These are to enhance the efficiency as well as lower the economic and environmental impacts of polygeneration systems. A shortcut methodology has also been developed as a decision-making tool for effective selection from a portfolio of CO2 abatement options and integrated systems. Critical and comprehensive analyses of all the systems under considerations are presented. These embrace the impact of carbon tax, product price evaluation and recommendations for sustainability of low carbon energy systems.EThOS - Electronic Theses Online ServiceOverseas Research Scholarship (ORS)The University of Manchester Alumni FundProcess Integration Research Consortium (PIRC)School of Chemical Engineering and Analytical Science (CEAS)GBUnited Kingdo

Methanol Worked Examples for the TEA and LCA Guidelines for CO2 Utilization

This document contains worked examples of how to apply the accompanying “Guideline for Techno-Economic Assessment of CO2 Utilization” and “Guideline for Life Cycle Assessment of CO2 Utilization”. The Guidelines can be downloaded via http://hdl.handle.net/2027.42/145436. These worked examples are not intended to be a definitive TEA or LCA report on the process described, but are provided as supporting material to show how the TEA and LCA methodologies described in the guidelines can be specifically applied to tackle the issues surrounding CO2 utilization. This document describes techno-economic assessment and life cycle assessment for methanol production. As methanol production via hydrogenation and PEM electrolysis of water to produce hydrogen are both at high technology readiness levels (TRL7+); a CO2 capture technology currently at a lower TRL (membrane separation at TRL3 or 4) was selected to demonstrate the differences that can be observed in the interpretation phase when working on TEA and LCA studies of processes with lower TRLs. It is acknowledged that there are many unknown variables with membrane capture, and it is not within the remit of this work to draw conclusions on their application. However, it is known that organizations wish to conduct TEA and LCA studies across a range of TRLs and therefore we hope to demonstrate here how this could affect the results. This document is one of several application examples that accompany the parent document “Techno-Economic Assessment & Life-Cycle Assessment Guidelines for CO2 Utilization”.Development of standardized CO2 Life Cycle and Techno-economic Assessment Guidelines was commissioned by CO2 Sciences, Inc., with the support of 3M, EIT Climate-KIC, CO2 Value Europe, Emissions Reduction Alberta, Grantham Foundation for the Protection of the Environment, R. K. Mellon Foundation, Cynthia and George Mitchell Foundation, National Institute of Clean and Low Carbon Energy, Praxair, Inc., XPRIZE and generous individuals who are committed to action to address climate change.https://deepblue.lib.umich.edu/bitstream/2027.42/145723/5/Global CO2 Initiative Complete Methanol Study 2018.pd

Decomposing long-run carbon abatement cost curves - robustness and uncertainty

Policy makers in the United Kingdom (UK), as in many countries around the world, are confronted with a situation of legally binding commitments to reduce carbon emissions. In this context it remains an open question of how to find a cost-efficient approach to climate change mitigation. Marginal abatement cost (MAC) curves have already been applied to help understand the economics of many different environmental problems and can likewise assist with illustrating the economics of climate change mitigation. Current approaches to generate MAC curves rely mostly on the individual assessment of each abatement measure, which are then ranked in order of decreasing cost-efficiency. These existing ways of generating MAC curves fail to allow both the graphical representation of the technological detail and the incorporation of system-wide behavioural, technological, and intertemporal interactions. They also fail to provide a framework for uncertainty analysis. This dissertation addresses these shortcomings by proposing a new approach to deriving MAC curves through the combination of an integrated energy system model, UK MARKAL, and index decomposition analysis. The energy system model is used to capture system-wide interactions, while decomposition analysis permits the analysis of measures responsible for emissions reduction. Sensitivity analysis and stochastic modelling are also employed to represent how sensitive the measures are to variations of the underlying drivers and assumptions, as well as how they interact. With a focus on the UK and the year 2030, as an important intermediate emissions reduction target, system-wide MAC curves are presented accompanied by a detailed analysis of the power, transport, and the residential sectors. This analysis allows important insights to be made into the economics of emissions mitigation, as well as investigating the robustness of findings. The results of the dissertation project represent a suitable orientation base for decision making in long-term climate policy

The JRC-EU-TIMES model - Assessing the long-term role of the SET Plan Energy technologies

The JRC-EU-TIMES model is one of the models currently pursued in the JRC under the auspices of the JRC Modelling Taskforce. The model has been developed over the last years in a combined effort of two of the JRC Institutes, IPTS and IET. The JRC-EU-TIMES model is designed for analysing the role of energy technologies and their innovation for meeting Europe's energy and climate change related policy objectives. It models technologies uptake and deployment and their interaction with the energy infrastructure including storage options in an energy systems perspective. It is a relevant tool to support impact assessment studies in the energy policy field that require quantitative modelling at an energy system level with a high technology detail. This report aims at providing an overview on the JRC-EU-TIMES model main data inputs and major assumptions. Furthermore, it describes a number of model outputs from exemplary runs in order to display how the model reacts to different scenarios. The scenarios described in this report do not represent a quantified view of the European Commission on the future EU energy mix.JRC.F.6-Energy systems evaluatio

Sustaining the low-carbon emission development in Asia and beyond: Sustainable energy, water, transportation and low-carbon emission technology

Climate change is global issues with significant economic, social and environmental implications. Climate change mitigation in Asia has large impacts on global CO2 emission reduction. CO2 emission is the largest source of greenhouse gas emission constitutes about 65% of the total emission. Low-carbon Society initiative is one of the various mechanisms that have been deployed to achieve green economic growth, societal well-being and development, environmental preservation and management in a holistic manner. Energy efficiency improvement in Asia will be a key factor to tackle the climate change issues. Water and energy conservation, green transportation and low emission technology are the key aspects to catalyse the shift towards climate-resilient economic growth. The latest developments in these aspects are reviewed in this special volume to sustain the development of low-carbon emission in Asian countries. The use of holistic management system to integrate these key areas for long-term sustainability goal is also highlighted

Technoeconomic evaluation of power-to-gas: modelling the costs, carbon effects, and future applications

Power-to-Gas (PtG) splits water into hydrogen and oxygen using electricity. As the hydrogen can be used directly or combined with carbon dioxide to produce methane, it has been mooted as a versatile renewable fuel especially suited to reducing transport emissions. PtG’s ability to flexibly consume electricity means that it can alleviate some of the issues associated with increasing amounts of variable renewable electricity (VRE) like wind, providing storage and ancillary services to the electricity grid. The sustainability of PtG (both hydrogen and methane) was examined in terms of cost and emissions using various methods and for a range of scenarios. Cash flow models were used to calculate the levelised costs, and sensitivity analysis was performed on these. Electricity market models were used to optimise the cost of the electricity consumed, and also to control the carbon intensity of the gas produced, while wind speed data and simulations of the electricity system produced results on directly pairing PtG with VRE. Each chapter also includes analysis of PtG regarding potential barriers to its implementation and niche applications, suitable to all energy stakeholders. Should zero cost electricity be available throughout the year it would result in a levelised cost of €55/MWh (55c/L diesel equivalent) for PtG (methane). However, in reality it is not viable to base PtG on otherwise curtailed or difficult to manage (zero cost) electricity alone, the resource is too small even at high VRE penetration; it is preferential to increase the run hours of gas production to a level that amortises the capital expenditure by bidding for electricity in the wholesale market. Results show that by optimising electricity consumption large savings in levelised costs can be achieved, but they are still dominated by electricity purchase (56%), followed by total capital expenditure (33%). The base levelised costs for PtG (methane) were found to be €124/MWh in 2020 which may fall to €93MWh in 2040, valorising the oxygen or grid services could reduce these by €19 and €37/MWh respectively. The majority of the life cycle emissions from PtG are due to the source of electricity, but by operating at times of low-cost or high forecast wind power, these can be reduced. Cleaner hydrogen production (up to a 56% reduction in carbon intensity) at a lower cost (up to 57% less) can be achieved when compared to hydrogen associated with the grid average. Synergistic effects that increased with VRE penetration were noted, meaning that ignoring emissions and instead minimising levelised costs using these controls still reduced the carbon intensity of the hydrogen produced by 5-25% for the bid price control and by 14-38% for the wind forecast control. Direct connection to an offshore wind farm was also considered though results suggest that curtailment abatement alone will not drive investment in PtG; high hydrogen values are a necessity. To justify converting all electricity to hydrogen, a developer would have to anticipate 8.5% curtailment and be able to receive €114/MWh of hydrogen, or 25% curtailment and €101/MWh. Hybrid systems are preferable and increase project value when hydrogen is sold for €106/MWh or more, otherwise selling electricity alone is more profitable. The strategies and configurations tested in this thesis allow for hydrogen/methane to be produced from electricity without exacerbating the mismatch of supply and demand. PtG has significant potential as a future source of low carbon transport fuel, especially in the haulage sector. However, in order to be competitive PtG systems must also valorise the ancillary services they provide and focus on optimising the consumption of electricity, as capital cost reductions alone are unlikely to sufficiently reduce levelised costs. The system wide benefits of PtG make it highly suitable for incentivisation especially in light of increased VRE penetration and ambitious renewable transport energy targets

Modelling framework for the design of hydrogen-CCS networks to decarbonise heating and industrial clusters

This dissertation elucidates the value of H₂ and CO₂ infrastructure in decarbonising “difficult-to-abate” sectors of the economy. We analyse infrastructure for low-carbon fuels and energy vectors at different scales, and present a flexible formulation to integrate relevant technologies for their interconversion. We use a mixed integer linear programming (MILP) approach to formulate spatial systems optimisation problems, and identify solutions that can accelerate the transition to low-carbon systems. The modelling framework can incorporate spatial and temporal granularity, whilst also capturing the nuances of a site, country, or an industrial cluster. Through its application, we outline a transition pathway for the natural-gas based heating sector to H₂ in Great Britain, noting the key barriers to cost-effective deployment. The cost-optimal supply mix contains natural gas reforming with CCS, flexible electrolytic H₂ production, large volumes of salt cavern storage, and biomass gasification with CCS to offset any remaining methane and CO₂ emissions from the natural gas supply chain, and the production plants. Given the uncertainties involved, we note that a complete conversion of the gas grid in the UK to H₂ for heating buildings is unlikely to be viable. We find that a portfolio-based approach containing post-combustion CO₂ capture, fuel switching with H₂, and negative emissions is a cost-effective strategy to decarbonise industrial clusters in the UK. This achieves greater decarbonisation and avoids an overreliance on CO₂ emission offsets. The total costs of CO₂ avoidance can be reduced by using existing fuels such as refinery fuel gases for H₂ production. Natural gas plays an important role as fuel and feedstock for post-combustion and methane reforming, and is the primary determinant of the total costs of the system. This has implications for the security of supply, given that countries such as the UK import as much natural gas as they produce domestically. A cradle-to-gate lifecycle assessment of reforming, and electrolytic H₂ production using grid power and offshore wind power, shows that the lowest global warming potential is generated using a dedicated renewable-led supply. However, none of the production pathways are dominant across all key environmental performance indicators. This indicates the potential for “problem shifting” to occur by solely focussing on a given pathway for long-term supply development. We note that the environmental performance of H₂ improves with reductions in upstream methane emissions, and an increase in the capacity factor of renewable power generation assets.Open Acces