Hydrogen injection into the gas grid: Current status and future potential

Hydrogen injection into the gas grid (HIGG) is an interesting application of power-to-gas that offers new opportunities for flexibility and decarbonisation in energy systems. The gas grid can provide a useful outlet and transportation mechanism for hydrogen, and the gas grid’s inherent storage capacity (“linepack”) could be exploited, absorbing fluctuations from the electricity grid, via power-to-gas. Many countries have extensive natural gas grids; HIGG is an option that would enable these valuable assets to continue operating whilst reducing carbon impacts.This work explores the technical and economic status of, and outlook for, HIGG, including the physical effects of hydrogen on the infrastructure, and the challenge of how to value hydrogen in the gas grid. The current status of HIGG is considered through a review of real-life projects and modelling studies.Although challenges exist, it is found that HIGG is technically feasible. Demonstrator projects in a number of different countries show the considerable interest that exists for HIGG. However, in present-day conditions, real-life projects and modelling studies struggle to find viable business cases. Although it would be a vast and costly undertaking, there is interest in complete conversion of gas grids to hydrogen, to enable decarbonisation

Data for spatio-temporal modelling and optimisation of multi-product rice value chains

A current and fully-referenced dataset of resources and technologies for rice provision system is presented in this paper. These data served as model input data for the first multi-objective spatio-temporal optimisation of Philippine rice value chains. Data on available farmland area and their characteristics, such as paddy rice yield, rice farming costs and GHG emissions, are reported. As scenarios were developed for optimal rice value chains of integrated food and non-food production, estimates on the spatio-temporal demands on food, energy, fuels and chemical are presented. Data on sale prices and GHG factors of the raw materials and products are also compiled. Processing and transporting technologies involved in the modelling have their economic and operating parameters presented in this paper. This dataset has been collated through academic journals, technical papers and government agencies; all of which have been properly referenced. These data are valuable to various stakeholders of the rice industry across the globe aiming to understand rice value chains optimisation studies and to conduct further scenario development under different conditions and assumptions.<br/

Should we inject hydrogen into gas grids? Practicalities and whole-system value chain optimisation

Injection of hydrogen into existing natural gas grids, either partially or as a complete conversion, could decarbonise heat and take advantage of the inherent flexibility that gas grids provide in a low-carbon future. However, hydrogen injection is not straightforward due to the differing properties of the gases and the need for low-cost, low-carbon hydrogen supply chains. In this study, an up-to-date assessment of the opportunities and challenges for hydrogen injection is provided. Through value chain optimisation, the outlook for hydrogen injection is considered in the context of a national energy system with a high reliance on natural gas. The optimisation captures the operational details of hydrogen injection and gas grid flexibility, whilst also modelling the wider context, including interactions with the electricity system and delivery of energy from primary resource to end-use. It is found that energy systems are ready for partial hydrogen injection now, and that relatively low feed-in tariffs (£20-50/MWh) could incentivise it. Partial hydrogen injection could provide a stepping stone for developing a hydrogen infrastructure, but large scale decarbonisation of gas grids requires complete conversion to hydrogen. Whether this solution is preferable to electrification in the long term will depend on the value of the gas grid linepack flexibility, and the costs of expanding electricity infrastructure

Data for spatio-temporal modelling and optimisation of multi-product rice value chains

A current and fully-referenced dataset of resources and technologies for rice provision system is presented in this paper. These data served as model input data for the first multi-objective spatio-temporal optimisation of Philippine rice value chains. Data on available farmland area and their characteristics, such as paddy rice yield, rice farming costs and GHG emissions, are reported. As scenarios were developed for optimal rice value chains of integrated food and non-food production, estimates on the spatio-temporal demands on food, energy, fuels and chemical are presented. Data on sale prices and GHG factors of the raw materials and products are also compiled. Processing and transporting technologies involved in the modelling have their economic and operating parameters presented in this paper. This dataset has been collated through academic journals, technical papers and government agencies; all of which have been properly referenced. These data are valuable to various stakeholders of the rice industry across the globe aiming to understand rice value chains optimisation studies and to conduct further scenario development under different conditions and assumptions.<br/

How to incentivise hydrogen energy technologies for net zero: Whole-system value chain optimisation of policy scenarios

Policy intervention is essential for enabling energy decarbonisation, and historic examples such as wind and solar power show how well-designed policy can lead to long term system benefits. Hydrogen technologies are emerging technologies that, with sufficient policy support, can also become established and provide valuable energy services. In this study, the policies available for supporting emerging energy technologies and encouraging system decarbonisation are analysed, and their relevance to hydrogen technologies is considered. Value chain optimisation is used to assess the effectiveness of these policies in a system undergoing transition to net-zero emissions. The optimisation results show that both carbon budgets and carbon taxation approaches can be effective in achieving net-zero emissions, but that the details of the policy design can significantly influence overall costs and emissions. The results also show that in a net-zero energy system, hydrogen technologies have a role in industry without needing specific policy support, but policy intervention is needed for hydrogen to become established in other sectors (such as domestic and commercial heating). Both feed-in tariffs and obligations for hydrogen injection were found to be effective at increasing hydrogen uptake, although with an increase in overall system cost of £11-14 for each additional MWh of hydrogen in the system. This study shows the benefits of using value chain optimisation to analyse energy policies and technologies. It also emphasises the importance of careful policy design in order to achieve the best overall system outcomes

Integrated production of fuels, energy and chemicals from Jatropha curcas: Multi-objective optimisation of sustainable value chains

In this work, a comprehensive optimisation model, based on mixed-integer linear programming, was developed that can support complex decision-making related to multi-product Jatropha value chains and can capture the trade-offs between water, energy and land utilisation. The model can identify promising Jatropha value chains for sustainable and efficient production of energy, fuels and chemicals. This paper presents the optimisation model and the key findings from a preliminary case study on biodiesel production for the Philippines.</p

What is the role for hydrogen in the UK energy system? Assessment of hydrogen storage and injection into the gas grid using whole-system value chain optimisation

With ambitions to achieve a net-zero emissions power generation sector by 2050, the UK will be increasingly reliant on intermittent energy sources such as wind and solar. This will lead to increased system variability, where energy supplies and demands do not always balance in time and space. Energy storage can be used to mitigate variability. Hydrogen, in particular, has great potential for large-scale energy storage.In this work, we use a comprehensive MILP optimisation model for Great Britain (GB) to assess how much energy storage is optimal and how to implement it, in a system with high penetration of renewable energy.The model accounts for time scales from hourly through to decadal, to capture all levels of variability, in addition to long-term system evolution. The GB system is represented with 16 spatial zones. The model simultaneously optimises the overall system design (e.g. what energy conversion, transport and storage technologies to install), and operating strategy on an hourly basis.A range of hydrogen technologies are investigated, including electrolysis, fuel cells, and hydrogen storage in pressure vessels and underground. Hydrogen injection into the gas grid is also modelled, to explore the extent to which the gas grid’s linepack flexibility can be exploited

The value of hydrogen and carbon capture, storage and utilisation in decarbonising energy::Insights from integrated value chain optimisation

There is increasing interest in carbon capture, utilisation and storage (CCUS) and hydrogen-based technologies for decarbonising energy systems and providing flexibility. However, the overall value of these technologies is vigorously debated. Value chain optimisation can determine how carbon dioxide and hydrogen technologies will fit into existing value chains in the energy and chemicals sectors and how effectively they can assist in meeting climate change targets. This is the first study to model and optimise the integrated value chains for carbon dioxide and hydrogen, providing a whole-system assessment of the role of CCUS and hydrogen technologies within the energy system. The results show that there are opportunities for CCUS to decarbonise existing power generation capacity but long-term decarbonisation and flexibility can be achieved at lower cost through renewables and hydrogen storage. Methanol produced from carbon capture and utilisation (CCU) becomes profitable at a price range of £72-102/MWh, compared to a current market price of about £52/MWh. However, this remains well below existing prices for transport fuels, so there is an opportunity to displace existing fuel demands with CCU products. Nonetheless, the scope for decarbonisation from these CCU pathways is small. For investment in carbon capture and storage to become attractive, additional drivers such as decarbonisation of industry and negative emissions policies are required. The model and the insights presented in this paper will be valuable to policymakers and investors for assessing the potential value of the technologies considered and the policies required to incentivise their uptake

Integrating fuzzy analytic hierarchy process into a multi-objective optimisation model for planning sustainable oil palm value chains

This study presents a novel integrated decision model for optimal planning oil palm value chains (OPVC) incorporating decisions to minimise biodiversity losses by limiting the expansion of oil palm plantations as needed and generate value from its waste products. The model can answer the following types of question: The planning model developed involves two components: (1) a decision framework using fuzzy analytic hierarchy process (FAHP) to incorporate experts’ knowledge in planning and design under uncertainty and (2) a mixed integer linear program (MILP) to determine the optimal expert-based OPVC design. The framework was applied to different scenarios for the Malaysian palm oil industry. Results show that the demand for crude palm oil (CPO) in Malaysia can be fully satisfied while the international demand can be satisfied by about 60% in 2050. However, in order to minimise environmental impacts and risks of biodiversity losses, the contribution of Malaysia towards satisfying global demand for palm oil should be kept to a minimum. Moreover, the current plantations can satisfy future CPO demand after 5 to 10 years, after which best practices to improve palm oil yield and alternatives comparable to palm oil will be needed. The framework can potentially contribute to the development of better policies in the future through the proposed systematic approach in dealing with sustainability issues in the palm oil industry.</p