Decarbonisation Targets Research Articles

Review and Perspectives of Key Decarbonization Drivers to 2030

Global climate policy commitments are encouraging the development of EU energy policies aimed at paving the way for cleaner energy systems. This article reviews key decarbonization drivers for Italy considering higher environmental targets from recent European Union climate policies. Energy efficiency, the electrification of final consumption, the development of green fuels, increasing the share of renewable energy sources in the electric system, and carbon capture and storage are reviewed. A 2030 scenario is designed to forecast the role of decarbonization drivers in future energy systems and to compare their implementation with that in the current situation. Energy efficiency measures will reduce final energy consumption by 15.6%, as primary energy consumption will decrease by 19.8%. The electrification of final consumption is expected to increase by 6.08%. The use of green fuels is estimated to triple as innovative fuels may go to market at scale to uphold the ambitious decarbonization targets set in the transportation sector. The growing trajectory of renewable sources in the energy mix is confirmed, as while power generation is projected to increase by 10%, the share of renewables in that generation is expected to increase from 39.08% to 78.16%. Capture and storage technologies are also expected to play an increasingly important role. This article has policy implications and serves as a regulatory reference in the promotion of decarbonization investments.

Reinforcing the Paris Agreement: Ambitious scenarios for the decarbonisation of the Central Asian and Caspian region

For its abundant fossil resources, the Central Asia and Caspian region plays a strategic role in the energy security of major markets, such as Europe and China. However, this dependence on export, added to a firm reliance on fossil fuels for internal consumption, represents a significant challenge for the decarbonisation of the region.In this paper, we perform an energy scenario analysis of four countries in the region (Azerbaijan, Kazakhstan, Uzbekistan and Turkmenistan), aiming to investigate how ambitious their regional decarbonisation targets for 2050 are in view of the Paris Agreement. We also develop a net-zero emission pathway to reinforce the regional climate ambition in the long term. As a novelty in the literature, the scenario analysis is co-designed with regional stakeholders through an engagement process that we have carried out from December 2020 to May 2021.The analysis is performed with the TIMES-CAC energy system model. Results show that current regional energy policies are insufficient for achieving ambitious climate targets in the long term (2050 and beyond). The lack of a long-term strategy to decrease the dependence on export increases the influence of importing countries’ energy policies. Even in a decarbonised scenario, the role of China remains significant, while the dependence on the European Union decreases. To limit the pressure from other countries in the energy transition, the region should start implementing a rigorous energy planning process today to fill the “ambition gap” and achieve carbon neutrality in a 40-year horizon.

Machine learning for performance prediction in smart buildings: Photovoltaic self-consumption and life cycle cost optimization

The application of Photovoltaic (PV) system in buildings is growing rapidly in response to the need for clean energy sources and building decarbonization targets. Nonetheless, enhancing PV self-consumption through technical solutions such as Energy Storage Systems (ESS) is getting higher importance to increase the profitability of PV plants, by minimizing the building-grid interaction. In this context, analyzing PV self-consumption of different energy storage configurations becomes more relevant and crucial in building energy modeling although it is heavily time-consuming and complicated, particularly within a multi-objective optimization related to the ESS design. As a solution to resolve this issue, this paper evaluates the accuracy, training, and prediction speed of 24 Machine Learning (ML) models to be used as surrogate models for analyzing PV self-consumption in smart buildings. Furthermore, the performance of short-term Thermal Energy Storage (TES) to increase PV self-consumption is assessed and presented using ML models. The results showed the Gaussian Process Regression (GPR), Neural Networks (NN) including bilayered and trilayered NN models, Support Vector Machines (SVM) including the fine gaussian and cubic SVM models, and Ensembles of Trees (EoT) as superior ML models. The results also revealed that TES systems can efficiently increase PV self-consumption in the building equipped with electric heat pumps to provide heating, cooling, and domestic hot water. Moreover, the TES size optimization regarding the Life Cycle Cost (LCC) showed that the LCC-based optimum TES size can yield 7.1% savings within 30 years of the building service life. The novelties of this research are first to provide a reference to select the most suitable ML models in predicting PV self-consumption, second to implement machine learning for analyzing the performance of short-term thermal energy storage to enhance PV self-consumption in buildings, and third to carry out an LCC-based optimization on TES size using ML-based prediction models.

Developing Tools to Enable the UK Construction Industry to Adopt the Active Building Concept for Net Zero Carbon Buildings

The research project discussed in this paper is driven by the United Kingdom’s (UK’s) need to reduce operational energy and carbon by promoting the adoption of the Active Building (AB) concept for UK building projects. The AB concept offers a practical solution to reducing the operational energy use and carbon emissions of buildings by using emerging technologies applied to architectural design; thus, helping the UK meet its decarbonisation targets and, consequently, helping to combat the global problem of climate change. The aim of the project was to design and implement an AB Protocol with an AB Toolkit, to provide a knowledge base and sustainable architectural design guidance to aid the design of ABs. The AB Toolkit was tested, evaluated, and refined by engaging with architectural designers in the UK through focus groups (FGs) that combined data collection with knowledge dissemination—a method which provided a contribution to the continuous professional development (CPD) of architectural designers in the UK, while aiding the research project. The FG data proved the original hypothesis that a whole host of measures are needed to support the adoption of the AB concept (as outlined in the AB Protocol), but that some design guidance was needed initially to enable the development of other supporting measures. Therefore, the main output of this research project was the development of a structured approach to enable architectural designers and other built-environment professionals to adopt the AB concept for the delivery of net zero operational energy buildings, supporting the aims of the SPECIFIC Innovation and Knowledge Centre, Swansea University, and the Active Building Centre (ABC). The method of data collection developed, and the structured approach to enabling the adoption of a new concept outlined, could be beneficial to other researchers.

Circular economy in road construction and maintenance

Implementation of the circular economy has the potential to significantly contribute to decarbonization targets. The CERCOM project will deliver an innovative risk-based framework to facilitate the adoption of Circular Economy (CE) and Resource Efficiency (RE) principles in procurement by National Road Authorities (NRAs) across Europe. This paper presents the interpretation of CE and RE within the highways sector to determine how NRAs define and assess their own performance against these topics. This informs data requirements for developing Key Performance Indicators (KPIs) for circularity while assessing quantity, quality, and availability of information required. The CERCOM Risk-Based Analysis framework is presented, which utilizes a weighted sum incorporating risk, cost and various KPIs developed to rank various construction and maintenance activities in terms of circularity and risk.

Ensuring accurate Key Performance Indicators for Battery applications by implementing consistent Reporting Methodologies

Batteries have been identified as a key technology enabling the transition to a low-carbon economy. To achieve the EU decarbonization target by 2050, the demand for high-performance, low-cost, and sustainable batteries is rapidly growing. Several battery technologies have been proposed for different applications, e.g., automotive, aviation, maritime, etc. In this rapidly evolving field, while key performance indicators can be readily accessed, the performance evaluation and comparison of battery technologies remain a challenging task, due to the huge variation in the quality and quantity of data reported and the lack of a common methodology. To address this challenge, Batteries Europe stakeholders have suggested reporting methodology guidelines which, if implemented, will facilitate the identification of the most promising cell technologies while highlighting areas for improvement.

Comparative analysis of the thermodynamic performances of solid oxide fuel cell–gas turbine integrated systems for marine vessels using ammonia and hydrogen as fuels

To mitigate environmental issues and implement energy management strategies, hydrogen is emerging as the most promising and sustainable energy source to help achieve decarbonization targets and meet world energy demands. However, hydrogen poses significant storage and transportation challenges due to its low volumetric and gravimetric density. Hence, ammonia is a potential candidate for a hydrogen storage medium because it contains 17.65% hydrogen by weight, and its volumetric hydrogen density is 45% higher than that of liquid hydrogen. In the maritime sector, these available fuels of ammonia and hydrogen are utilized via internal combustion engines, fuel cells, and gas turbines, which are employed on board ships. This study investigates the possibility of using ammonia and hydrogen as fuels for Solid Oxide Fuel Cells (SOFCs). A combined SOFC-Gas Turbine (GT) system was proposed to generate power for marine propulsion plants. This system was designed and modeled with support from Aspen HYSYS V.12.1. Thermodynamics performances of the proposed system were analyzed using the first and second laws of thermodynamics. The energy efficiencies of direct ammonia and hydrogen SOFCs were 60.96 and 64.46%, respectively. The energy efficiencies of the combined systems increased by 12.37 and 13.97% when using ammonia and hydrogen as fuels, respectively, compared with that of single SOFC systems. The exergy destruction of the primary components with each fuel was examined. Furthermore, a parametric study was performed to select the most suitable fuel utilization factor for the system. This analysis proved that ammonia has the potential as a hydrogen carrier and that waste heat recovery is an effective method to improve the thermodynamic performance of an SOFC system.

Analysis of the impact of offshore wind power on the Japanese energy grid

<abstract> <p>As part of its economy-wide decarbonization target towards 2050, Japan plans to increase renewable generation, especially offshore wind, for which the country has a high potential. However, this resource is currently under-developed as available turbines are prone to shut-downs and can even suffer damage during the passage of typhoons. With new typhoon proof (T-class) turbines being currently developed by various companies, Japan now aims to develop 10 GW of offshore wind between 2021 and 2030, and 91 GW in the long-term. This research estimates the impact of integrating offshore wind into the Japanese main power grid using T-class turbines by considering three scenarios. First, a business-as-usual (BAU) case with 10 GW offshore wind capacity (following the 6<sup>th</sup> Strategic Energy Plan of Japan). Second, an offshore wind capacity of 91 GW. Third, the 91 GW offshore capacity being redistributed amongst regions to maximize its integration opportunities (Scenario 2). The simulations were carried out using the Energy System simulation model (EnSym). The results show that the BAU and Scenario 1 resulted in offshore wind achieving 1.7% and 7.28% of generation share, respectively, increasing to 9.77% for Scenario 2. Increasing the share of offshore wind in the energy mix mainly replaced liquefied natural gas (LNG).</p> </abstract>

Meeting Decarbonization Targets: Techno-economic Insights From the Italian Scenario

Meeting Decarbonization Targets: Techno-economic Insights From the Italian Scenario

A bigger bang for the buck: The impact of risk reduction on renewable energy support payments in Europe

Decarbonizing Europe by 2050 requires significant capital investments in renewable energy (RE). The weighted average costs of capital (WACC) greatly impact RE production costs and influence the government support payments needed for the financial viability of RE projects. Reducing the risks for RE investors can decrease WACC and ensure that the EU meets its climate targets at the least cost. We investigate the potential for lowering support payments to RE projects by de-risking financing conditions through measures including revenue stabilization and low-risk auction designs for solar PV and onshore wind across 21 countries in Europe. We find that de-risking debt is almost twice as effective as de-risking equity. On average, support payments can be reduced by 3.3 EUR/MWh and 1.9 EUR/MWh, respectively, and in some cases, fall to zero. The effects differ across countries, higher-risk countries like Greece would experience more significant benefits from de-risking than lower-risk countries like Denmark and Germany, where support costs depend more on investment variables such as capacity factors. Overall, we show that WACC depends largely on country risk. Nonetheless, de-risking policies like revenue stabilization can improve the investment climate for RE, reduce the need for government support, and contribute to achieving decarbonization targets.

Towards the Integration of Flexible Green Hydrogen Demand and Production in Ireland: Opportunities, Barriers, and Recommendations

Ireland’s Climate Action Plan 2021 has set out ambitious targets for decarbonization across the energy, transport, heating and agriculture sectors. The Climate Action Plan followed the Climate Act 2021, which committed Ireland to a legally binding target of net-zero greenhouse gas emissions no later than 2050, and a reduction of 51% by 2030. Green hydrogen is recognized as one of the most promising technologies for enabling the decarbonization targets of economies across the globe, but significant challenges remain to its large-scale adoption. This research systematically investigates the barriers and opportunities to establishing a green hydrogen economy by 2050 in Ireland, by means of an analysis of the policies supporting the optimal development of an overall green hydrogen eco-system, in the context of other decarbonizing technologies, including green hydrogen production using renewable generation, distribution and delivery, and final consumption. The outcome of this analysis is a set of clear recommendations for the policymaker that will appropriately support the development of a green hydrogen market and eco-system in parallel with the development of other more mature low-carbon technologies. The analysis has been supplemented by an open “call for evidence,” which gathered relevant information about the future policy and roles of hydrogen involving the most prominent stakeholders of hydrogen in Ireland. Furthermore, the recommendations and conclusions from the research have been validated by this mechanism.

Pathway for the low-carbon consumption pattern transition of residents in six eastern coastal provinces of China: using fuzzy-set qualitative comparative analysis with panel data.

China has embarked on society-wide emission reduction initiatives to tackle the growing decarbonization pressures on national economic and social development. The low-carbon consumption pattern transition of the residential sector is viewed as a crucial impetus that will drive society toward sustainable development. However, how such a consumption transition can be facilitated remains unclear. By adopting 2015-2019 provincial panel data, this study assesses the carbon emissions associated with the consumption patterns of residents in Eastern China and further explores the causal relationships between policy and socioeconomic factors as well as the formation of a low-carbon consumption base using fuzzy-set qualitative comparative analysis method (fsQCA). This study explores five equivalent recipes that achieve the expected low-carbon consumption base and then classifies them into market-driven (M1) and tertiary-driven (M2) recipes. Longitudinal analysis based on the between consistency (BECONS) and the within consistency (WICONS) values reveals that the tertiary-driven pathways remain highly stable across time, whereas those pathways that heavily rely on market interventions may be more applicable in certain cases. Accelerating the low-carbon consumption transition via the explored pathways is expected to exert pressure on the production transition, and this study provides suggestions for regions with varied development levels to balance the trade-off between China's social development and its decarbonization targets.

Tracking the Biogenic Component of Lower-Carbon Intensive, Co-Processed Fuels—An Overview of Existing Approaches

Several methods are currently used to track the bio-component of co-processed fuels including energy/mass balance, yield methods and radiocarbon techniques. The methods used to track or estimate the bio-component of fuels produced when bio and fossil feedstocks are processed together (co-processed) in oil refineries were analysed in detail, together with their advantages and disadvantages. Some methods, such as radiocarbon methods that allow the direct measurement of the bio-content in a fuel, have been criticised due to low accuracy at low blends. However, these reservations have tended to misinterpret the options available for carbon dating and to discount recent improvements in these tests. As much higher co-pressing mixtures are anticipated if published national decarbonisation targets are to be achieved, any challenges at very low co-processing ratios affecting the accuracy of the radiocarbon methods should not be an issue. Energy/mass balance and yield methods might be supplemented with carbon-tracking to determine the real the biogenic content.

Co-benefits from tree planting in a typical English agricultural landscape: Comparing the relative effectiveness of hedgerows, agroforestry and woodland creation for improving crop pollination services

Land use policy in England is encouraging tree planting on farms to meet decarbonisation targets. This could be delivered through woodland creation, hedgerow planting or agroforestry. All three approaches could provide co-benefits for wild bee populations and crop pollination services, by increasing nesting and floral resources, but their relative effectiveness has not been studied at a landscape scale. We simulated six tree planting scenarios and used a validated process-based model to predict their effect on bumblebee abundance and pollination service to two common mass-flowering crops (oilseed rape and field beans) in a representative 10x10km agricultural landscape in England, UK. Two levels of planting intensity were studied: one representing the tree cover that would be achieved by 2035 if the 2020 woodland creation rate continues and another reflecting UK Government ambitions (threefold increase in planting rate). Hedgerow planting and woodland were predicted to give the biggest increase bumblebee abundance. Silvoarable agroforestry using fruit trees or willow was predicted, on average, to give the biggest increase in crop pollination service. However, the magnitude of increase was highly variable and hedgerow creation (which is more dispersed across the landscape) provided a more consistent increase in crop pollination services. Agroforestry with poplar (which offers less floral resource) and woodland creation (which concentrates tree planting in fewer locations) were only effective at enhancing landscape-level crop pollination at high planting intensity. Future land management policy should promote fruit tree and willow-based agroforestry as multifunctional tree planting measures in arable contexts, whilst continuing to encourage hedgerow planting and woodland creation for their role in promoting abundance and diversity of pollinators. Hedgerow planting may be needed alongside agroforestry to help stabilise pollination service through a crop rotation cycle.

Assessment of Climate Change Mainstreaming in Spatial Planning at the Central Level in Kosovo

Abstract Spatial developments contribute to climate change through greenhouse gas emissions and disordered land use. At the same time, climate change impacts have spatial implications, influencing the land uses and settlements development, and damaging habitats, ecosystems, infrastructure and other assets. Considering its regulatory character and multi-sectorial approach, spatial planning is gaining an increasingly important role in climate change management. As such, it could be better utilized in increasing climate resiliency and achieving decarbonization targets in Kosovo as well. While Kosovo is prone to natural hazards such as floods, landslides, droughts, and wildfires, the future climate change could further impact the economy, infrastructure, buildings, energy, health and wellbeing of its communities. Assuming that climate change considerations are not sufficiently integrated in spatial planning policies at the national level in Kosovo, this research assesses the extent that the Law on Spatial Planning and the Spatial Plan of Kosovo (also referred as the Spatial Planning Strategy) address those considerations. Upon the identified gaps, this research provides recommendations for better climate change management, risk reduction and resiliency building. Considering that the Spatial Plan of Kosovo has expired, and the Kosovo’s institutions are currently reviewing and considering the updating of the Law on Spatial Planning, the findings of this research could better inform and orient climate change mainstreaming in spatial planning at the central level.

Energy Performance of Annual Operation of Heat Pump Coupled with Ground Ice Storage and Photovoltaic/Thermal modules

The use of heat pumps for annual climatization is a suitable mean of achieving the 2030 European decarbonization target (-55% with respect to 1990 CO2 emissions). The use of seasonal energy storages allows to store one of the two contemporaneous effects (thermal and cooling energy) produced by the heat pump to be used successively when it is necessary. This paper focuses on a dynamic simulation to size the heating and cooling plant and define a suitable control logic for a refurbished building located in northern Italy. The plant is set up by an electric heat pump in annual operation, coupled with a ground ice storage. Ice produced during heating operation is used in summer to face cooling loads (free cooling). PhotoVoltaic/Thermal modules allow to increase the grid independency and to reduce primary energy consumption of the plant as they can be suitably cooled in any season, by recovering heat for domestic hot water or the ground. A dynamic simulation of the system allows for a full description of the behaviour of the ice tank during the charging and discharging processes. In addition, a primary energy performance analysis of the whole plant is reported, also in comparison to a dual source heat pump configuration for the same building.

Delivering a net zero carbon built environment – Targets and Pathways

Carbon neutrality is expected to address climate change challenges, and its achievement requires the collective efforts of various industries and sectors. The building and construction sector is a big energy consumer and greenhouse gas emitter, providing numerous opportunities for carbon neutrality. This indicates a need for a net zero carbon built environment, although the targets and pathways to it are still unclear. The paper, therefore, aims to address this research gap by reviewing the existing definition of net zero carbon and the targets set by international institutions (e.g., GABC, WorldGBC, RIBA, LETI, and AIA). The paper also defines the principles behind setting the decarbonisation targets, and presents the pathways tailored to the Australian building and construction sector. Overall, this paper is of importance in demonstrating a methodological framework for determining the net zero operational and embodied carbon targets and the associated pathways for decarbonising the built environment. The method is expected to be suitable for many other nations.

Capacity evaluation of central air conditioning load participating in peak shaving of renewable dominated power systems

The development of renewable-dominated power systems (RDPS) in the context of pursuing deep decarbonisation targets necessitates suitable exploitation of the peak shaving capacity (PSC) of central air conditioning loads (CACL) in multiple time scales. Based on the evaluation framework of CACL participating in the RDPS PSC and the CAC apparent temperature model and its operation mode, the CACL PSC evaluation model related to the resource allocation in multiple time scales is proposed. For the time scale of online dispatching, the capacity evaluation model for rapid CACL response to power system emergency peak shaving command and its continuous response potential is constructed. The method of optimising CACL PSC based on the load aggregator model is developed. For the intraday pre-scheduling time scale, the evaluation model of CACL's remaining capacity after undertaking the peak shaving task and the ability to respond continuously to the peak shaving command is constructed. For the day-ahead dispatching time scale, the PSC of CACL under different weather conditions, temperatures, holidays, and other typical scenarios is evaluated. Finally, case studies carried out on 14 central air-conditioned buildings in Shanghai city comprehensively validate the effectiveness of the proposed CACL PSC evaluation model.

The PRISMI Plus Toolkit Application to a Grid-Connected Mediterranean Island

Islands are a constrained environment due to their geographical peculiarities and their land use accounting for, especially in the touristic locations, strong variability during the year. Consequently, the variation of energy demand to be met by variable renewable energy leads to a complex issue. This study aims at investigating the PRISMI Plus approach applied to the Island of Procida to drive the transition towards low-carbon and high-renewable energy system. The toolkit involves the analysis of local renewable energy potential, their potential matching of the energy demand, and the prioritization of the technological solutions to achieve the decarbonization targets set by the energy planning strategies. Three scenarios are designed for 2030 considering low, middle, and high penetration of renewable energy in the systems, results indicate that the amount of power production in low, middle, and high penetration of renewable energy scenarios are 0.18, 14.5, 34.57 GWh/year, respectively. The environmental and landscape constraints lead to a restricted set of available solutions. The decarbonization of the electricity supply is foreseen thanks to the available local solar resources plus the electrification of other sectors, i.e. heating by using Heat Pumps and transport by using Electric Vehicles.

Narrowing fossil fuel consumption in the Indian road transport sector towards reaching carbon neutrality

Road transportation accounts for 56% of India's transportation sector's CO2 emissions. Reaching carbon neutrality before 2070 requires the deep decarbonization of this sector. This study assesses the potential of battery electric vehicles (BEV) and fuel-cell vehicles (FCV) as the least-cost pathway toward carbon neutrality. We estimate the future demand for passenger and freight services and evaluate the impact of EV policies using the Integrated Model of Energy, Environment, and Economy for Sustainable Development/Technology (IMED/TEC). The study covers road transport emissions, energy, and air pollution transitions under four scenarios, including reference, low, medium, and high penetration of BEV and FCV, which align with the decarbonization target agreed upon under India's national policy. Results show that the carbon neutrality target would be challenging with BEV alone in road passenger and freight transportation because it is less efficient. Combined penetration of BEV and FCV can reduce air pollutant emissions significantly. Operative implementation of FCV could diminish more than 96% of the total road transport CO2 emissions. The analytical framework also proposes local climate change policies towards a carbon neutrality strategy to escalate the share of BEV and FCV in the Indian road transport sector.