Primary Energy Use Research Articles

Do Environmental Tax and Energy Matter for Environmental Degradation in the UK? Evidence from Novel Fourier-Based Estimators

Currently, the UK has ambitious plans to reach net zero by 2050, despite other countries such as Russia and India targeting 2060 and 2070, respectively. Assuming that the UK emissions unceasingly decline at a given rate annually towards achieving net zero by 2050, its economy would need to ensure a reduction of 105 MtCO2 per year of its emissions from the current 2021 levels. Given that global greenhouse gas emissions have not peaked and continue to rise, the UK seeks to implement costly and aggressive emission reduction policies towards fulfilling commitments under the 2021 Glasgow Climate Pact. This paper investigates the effect of environmental taxes on environmental degradation in the UK between 2000Q1 and 2019Q4 using novel Fourier approaches. Using the novel Fourier ARDL estimator, the long-run equilibrium estimates indicate that gross domestic product and environmental tax cause a fall in carbon emissions. However, in trade and primary energy use, a unit change caused rising carbon emissions in the UK. Especially, the results indicate that environmental taxes have a negative effect on environmental degradation in the UK, and ecological tax policy could be considered as an effective channel to attain environmental sustainability. The outcome provides the following policy insights: (i) The government of the UK should support international environmental tax coordination mechanisms, especially on carbon pricing, to avoid relocation of carbon-intensive investments. (ii) The UK government must note that imposing more taxes to encourage emissions reductions could bring complexity to the tax system and unnecessarily bring costly ways to deal with climate change. Higher domestic electricity prices could disproportionately hit low-income households and create distributional cost concerns, which require benefit payouts or compensation schemes. (iii) Switching to electric vehicles simultaneously requires investments in charging infrastructure and battery technologies. To avoid this chicken-and-egg problem, the government of the UK could play a coordinating role, including deploying targeted subsidies, regulations, direct government involvement, or setting higher carbon prices in special cases.

Optimal operating strategy of hybrid heat pump − boiler systems with photovoltaics and battery storage

The growing need to reduce energy consumption and greenhouse gas emissions is driving the search for more efficient heating solutions in buildings. Hybrid heating systems, which combine air-to-water heat pumps (AWHP) with traditional gas boilers, are a common solution after refurbishment investments. However, managing these systems effectively, particularly when integrated with photovoltaic (PV) panels and battery energy storage systems (BESS), remains a complex task. For instance, heat pumps perform poorly in very cold conditions, making boilers a more efficient option; however, it might be advantageous to use it to increase electricity self-consumption. Optimal management depends on multiple factors, including future forecast data. In this paper, a daily optimization program is developed by means of a brute-force approach using forecast data. The core innovation of this paper is the use of an artificial neural network (ANN) that, trained on predictive optimization results, can determine the optimal solution in real-time without the need for future forecasts. The ANN achieved a 99.16% accuracy in new scenarios, successfully optimizing costs, CO2 emissions, and primary energy use. Results indicate up to 19% cost savings in colder cities, a 12% reduction in CO2 emissions, and a 3% decrease in primary energy consumption. This approach holds significant potential for enhancing the integration of renewable energy sources, contributing to long-term sustainability goals.

Does access to energy matter? Understanding the complex nexus among energy consumption, ICT, foreign direct investment and economic growth on carbon emissions in Sub-Saharan Africa

Carbon emissions and energy accessibility have emerged as significant obstacles to society's sustainable growth. This study investigates the non-linear impact of access to energy on carbon emissions by constructing a fixed-panel double-threshold regression model. The analysis utilises data from 2000 to 2019, encompassing 45 countries in Sub-Saharan Africa. The results outline that by employing the proportion of the population with access to electricity as the threshold parameter, the initial phases of foreign direct investment significantly lower carbon emissions. However, the later stages of FDI demonstrate an attenuated significantly positive link with carbon emissions. Secondly, by using the population with access to electricity as the threshold factor, primary energy consumption develops a significant and positive relationship with emissions in the initial levels that becomes more robust in the later intervals. Moreover, economic growth generates a positive relationship with environmental quality. However, the association between ICT and emissions is insignificantly positive. The D-H causality test results prove a bi-directional causal link between economic growth and carbon emissions, primary energy use and environmental quality, as well as ICT and emissions. The research proposes a comprehensive strategy for achieving sustainable development in Sub-Saharan Africa. Policymakers may develop policies for promoting clean energy access, responsible use of information and communication technology (ICT) and attracting environmentally aware foreign investment by examining the derived outcomes of the relationship between energy access, ICT, foreign direct investment (FDI), economic growth effects, and carbon emissions.

The environmental performance of zero-emission buildings in a fossil-free energy system

Buildings can play an important role in reducing GHG emissions through increased energy efficiency. The European Commission mandates that all new buildings should be “zero emission buildings” (ZEB), aiming at a zero GHG emission building stock by 2050. The extent to which ZEB can contribute to reduced GHG emissions, however, varies between countries, due to different energy systems. It is also important to consider other environmental effects to avoid that climate benefits come with unintended consequences. Here, we explore the life-cycle environmental performance for a ZEB in a case where electricity and heating are largely fossil-free. The assessment concentrates on i) environmental impact of the use stage in relation to the product stage, ii) the interrelation between different energy sources, with focus on household electricity, and iii) the performance for more impact categories than primary energy use and climate change. While our results generally support the use of ZEBs from an environmental perspective, they also show that the climate benefit in this setting is marginal. However, given that energy systems are connected and energy savings in one place can reduce the demand for fossil energy elsewhere, the climate benefit of ZEBs is likely underestimated. Besides methodological implications for future studies, this indicates that current EU policy is promising, as incentives for implementation of ZEBs are unaffected by domestic effects.

Assessing the Impact of ASEAN’s Harmonised Minimum Efficiency Performance Standards on AC Manufacturers

Abstract The residential sector in ASEAN is highly dependent on cooling as a primary energy use along with cooking, making up about 82% of the sector’s demand in 2050. Air conditioner (AC) is one of the cooling appliances in ASEAN that will drive energy demand growth in ASEAN. Consequently, this surge in demand also contributes significantly to the region’s CO2 emissions. Recognizing the impact of AC utilisation, energy efficiency in AC is considered the most effective way to propose energy savings and environmental impacts. In order to improve energy efficiency in AC, ASEAN has committed to stringent Minimum Energy Performance Standards (MEPS) by achieving a target for a Cooling Seasonal Performance Factor (CSPF) of 3.7 by 2023 and 6.09 by 2025. However, an update of MEPS across the ASEAN region has key two challenges: Firstly, the financial investment required by manufacturers; and secondly, the development and evolution of AC technology. This study aims to utilise Techno-Economic Assessment (TEA) to evaluate the impact of increased MEPS on AC manufacturers in the ASEAN region, with MEPS levels forming the framework for the TEA. The findings from this study offer valuable insights to manufacturers and policymakers, particularly regarding the impact of increased MEPS on AC manufacturers.

Solution of the modular PCM-based cooling ceiling and ventilation system

Most newly constructed buildings are now built to energy-passive standards, which set requirements for specific heating demand, non-renewable primary energy use, building envelope airtightness, and the frequency of exceeding permissible indoor air temperatures in summer. These temperature exceedances relate to the room’s thermal stability, determined by the potential for heat accumulation in surrounding structures over the daily cycle. For buildings with lightweight construction, implementing a Thermal Energy Storage (TES) solution can significantly enhance their energy accumulation ability. This article addresses the design and evaluation of a progressive cooling ceiling system combined with active ventilation system components, including the incorporation of TES based on PCM materials. The proposed solution aims to improve the thermal stability of occupied spaces, thereby significantly reduce the need for mechanical cooling. The research developed a new methodology for measuring the energy performance parameters of modular cooling ceiling systems, with its implementation thoroughly discussed. The evaluation of this solution was conducted within the context of the entire energy system for a reference building, considering various construction types (lightweight, medium, heavy). The overall potential energy savings range from 13% to 32%, depending on the building’s construction, while still meeting the required thermal comfort criteria.

Towards harmonising energy performance certificate indicators in Europe

Achieving the European Union's ambitious goal of transforming buildings into carbon-neutral assets is crucial for combating climate change and improving energy efficiency. The harmonization of Energy Performance Certificates (EPCs) plays a vital role in this effort. It can provide a standardized measure of building energy performance, which is crucial for benchmarking and improving energy efficiency across Member States. In the context of the recast Energy Performance of Buildings Directive (EPBD) of 2024, this study examines the progress made by EU Member States in standardizing EPCs. The research aims to evaluate the implementation of EPC indicators, focusing on data quality, calculation methods, and costs. The methodological procedure followed for the study led to the development of a dedicated Cross Comparative Matrix (CCM) to assess the implementation of EPC indicators across 27 EU Member States and their reading feature allowed the declination into three scenarios for different EPC data analysis: qualitative, quantitative and burden costs. The findings reveal significant disparities, particularly in areas such as thermal comfort and smart readiness, due to the lack of a common methodology and local regulatory differences. While key indicators like energy performance class and primary energy use are widely implemented, compliance with EU standards varies. The study concludes by recommending standardized methodologies and enhanced assessor training to improve EPC quality, harmonization, and effectiveness. This research contributes to policy discussions by offering a comprehensive framework for EPC evaluation and insights into improving data quality, reliability, and accessibility. The originality of this study lies in its cross-national analysis, highlighting the need for a unified EPC scheme to promote building sustainability across the EU.

Volumetric Add-On Retrofit Strategy with Multi-Benefit Approach toward Nearly Zero Energy Buildings Target

Around 35% of the total housing stock of the European Union is more than half a century old. The shortage of funds for new construction, combined with rapidly changing economic, social, and technological factors, has led to significant obsolescence. Additionally, this situation makes it difficult to satisfy the owners’ energy, functional, and socio-economic needs. This research aims to develop an innovative retrofit approach that brings multiple benefits to assessing retrofit designs for social housing, with specific emphasis on volumetric envelope additions toward the nearly zero energy buildings target (nZEBs). To achieve the purpose of this study, the research through design methodology was chosen. The research methodology consisted of two phases: design and simulation. First, the design phase focused on re-designing and retrofitting social housing to address various aspects of the functional requirements in developing rational solutions. Second, the simulation phase focused on computational modeling and analysis of energy performance to assess the nZEBs target. The results show that the use of high-efficiency Heating, Ventilation, and Air Conditioning (HVAC) systems and improved material envelopes cut electricity consumption use by 43% and primary energy use by 40% compared to the base case. Photovoltaics (PV) production can meet the total electricity demand for six months. This approach can encourage residents and tenants to actively participate in the retrofit process and increase the real estate value of buildings through improvements in energy efficiency and housing function.

Optimizing Energy Efficiency and Environmental Sustainability in Gas Distribution Station: A Comprehensive Analysis and Technological Solutions

It is important to address the world‘s energy crisis, increasing energy demand and changing climate by finding ways to recover unused energy and minimise primary and secondary energy use and emissions. The natural gas sector, which consists of the transmission network and gas distribution stations, is an important part of the global and Lithuanian energy sector. However, due to the operating principle of gas pressure regulators, the energy potential of high-pressure gas is not efficiently utilized in gas distribution stations. As a result, natural gas boilers are used for gas preheating, and gas distribution stations cause additional environmental pollution. This study aims to find ways to optimise the efficiency of gas distribution stations and reduce their negative environmental impact by identifying areas where energy is wasted and proposing alternative technological solutions: turbine expander (as an alternative for gas pressure regulator), ground heat pumps, solar collectors and photovoltaic solar cells (as gas preheating alternatives). The best alternative technological solution for the gas distribution station is evaluated based on energy efficiency, economic viability, and environmental impact (3E criteria).

Economy-wide rebound and the returns on investment in energy efficiency

In this paper we re-examine the relationship between global Gross Domestic Product (GDP), Primary Energy Use (PEU) and Economic Energy Efficiency (EEE) to explore how investment in energy efficiency causes rebound in energy use at the global scale. Assuming GDP is a measure of final useful work, we construct and fit a biophysics-inspired nonlinear dynamic model to global GDP, PEU and EEE data from 1900—2018 and use it to estimate how energy efficiency investments relate to output growth and hence economy-wide rebound effects. We illustrate the effects of future deployment of enhanced energy efficiency investments using two scenarios through to 2100. The first maximizes GDP growth, requiring energy efficiency investment to rise ~ twofold. Here there is no decrease in PEU growth because economy-wide rebound effects dominate. The second scenario minimizes PEU growth by increasing energy efficiency investment ~ 3.5 fold. Here PEU and GDP growth are near fully decoupled and rebound effects are minimal, although this results in a long run, zero output growth regime. We argue it is this latter regime that is compatible with the deployment of enhanced energy efficiency to meet climate objectives. However, while output growth maximising regimes prevail, efficiency-led pledges on energy use and emissions reduction appear at risk of failure at the global scale.

Remote Solar Parks for Building Decarbonisation: A Lithuanian Case Study on Virtual Prosumers

To reduce the carbon footprint of buildings, the concept of virtual prosumers (consumers who both consume and produce) using remote solar energy parks represents a novel method in Europe. In 2019, Lithuania became the first country in Europe to introduce a digital platform that enables the buying or renting of parts of a remote solar park, making it the first such platform in the world to operate on a national scale. This study examines the effectiveness of this model in Lithuania, assessing the model's success, public engagement, and success factors. The main study focus is on evaluating the impact of remote solar parks on the decarbonization of buildings, particularly through the prism of virtual prosumer participation.Applying a mixed research method, this study integrates both qualitative and quantitative data. The quantitative analysis includes a detailed case study, evaluating the amount of energy produced by two selected remote solar parks in Lithuania, as well as their impact on the carbon dioxide emissions and primary energy use of the two individual houses (a detached house and a unit within an apartment building) connected to these remote power plants. Concurrently, qualitative methods involve analyzing the existing legal and economic frameworks in Lithuania and Europe, which either facilitate or impede the prosumer model, in addition to examining the necessary technological infrastructure.Key findings of this study highlight the potential of remote solar energy parks to significantly reduce the carbon emissions of buildings. This model is especially beneficial for structures where onsite solar energy solutions are impractical. It fosters greater inclusivity in adopting renewable energy, enabling a variety of stakeholders to participate in and benefit from clean energy production. However, the study identifies several major challenges, including regulatory restrictions, the need for infrastructure development, a shortage of developers, state contributions, public awareness, and the creation of a unified platform.

Well‐to‐wheels analysis of greenhouse gas emissions for passenger vehicles in Middle East and North Africa

AbstractBattery electric vehicles (BEVs) are widely considered a pathway to achieve low carbon mobility. BEVs emit zero emissions from the tailpipe, but their life cycle carbon reduction compared to gasoline vehicles varies based on primary energy sources, electricity generation, and use efficiency. The Middle East and North Africa (MENA) region is an area rich in fossil fuels, meriting a detailed comparison between the emissions from BEV and other powertrains. We developed a MENA‐specific life cycle model that estimates well‐to‐wheel (WTW) greenhouse gas (GHG) emissions from passenger transport with internal combustion engine vehicles (ICEVs), hybrid electric vehicles (HEVs), plug‐in hybrid electric vehicles, and BEVs. MENA's average WTW GHG emissions for all supply chain steps including combustion emissions from vehicle operation are 767 g/kWh and 84 g CO2eq/MJ for electricity and gasoline, respectively, but are highly variable due to heterogeneity in upstream supply chains. The use of hybrid gasoline ICEVs provides the largest emission reduction opportunity for existing vehicle fleets in 9 of the 16 MENA countries. For these nine countries, replacing gasoline ICEVs with HEVs could, on average, reduce country‐level life cycle GHG emissions by 47%. There is a similar emission reduction opportunity for 14 of the 16 MENA countries when normalizing vehicle efficiencies irrespective of the powertrain shares and other trends in existing vehicle fleets. Future scenario analysis shows that BEVs would have the lowest WTW GHG emissions among all powertrains in most MENA countries only if significantly reduced electricity transmission losses and cleaner grid mix are realized, although a high cost of infrastructure developments is expected.

Primary Energy and Carbon Impacts of Structural Frames with Equivalent Design Criteria: Influence of Different Materials and Levels of Prefabrication

This study aims to analyze the life-cycle primary energy and climate impacts of structural frames, paying particular attention to the design and prefabrication of different structural materials. The study considers an existing single-story office building with a composite concrete–steel structure and compares it with two functionally equivalent structures, i.e., a conventional reinforced concrete structure and a conventional steel structure. The existing building is located in San Felice sul Panaro, Italy. This study integrates dynamic structural analysis and life-cycle assessment (LCA). The study finds that the use of different materials can reduce the life-cycle primary energy use and CO2-eq emissions by up to 12%. Furthermore, the benefits derived from the recovery and recycling of materials can reduce the primary energy use and CO2-eq emissions by up to 47% and 36%, respectively. The prefabrication of structural elements can also reduce the primary energy use and CO2-eq emissions in the construction stage. A sensitivity analysis considers changes in the electricity supply system and shows that the primary energy and CO2-eq emissions due to prefabrication decrease when assuming marginal electricity based on renewable energies. This analysis supports the development of sustainable structural design to meet the standards concerning the whole-life-cycle carbon emissions of buildings.

Energetic and financial evaluation of a district heating network under varying supply temperatures and booster technologies

Low-temperature district heating (LTDH) enables the use of various renewable energy sources, reduces heat losses and increases the energy efficiency of the distribution network. LTDH is especially applicable in energy-efficient buildings as the supply temperature for space heating can be reduced. However, urban areas consist of energetically refurbished and non-refurbished buildings. In these scenarios a LTDH network with a central heat pump (HP) and decentral booster units, such as a booster HP or electrical heater, can be a solution. This study investigates and compares the energetic performance and levelized cost of heat (LCOH) of eight concepts for refurbished and non-refurbished buildings for a district heating network in the city of Ghent, Belgium. The simulations consider supply temperatures ranging from 10 °C to 75 °C. Results show that the primary energy use is lowest when using booster HPs, for both refurbished buildings (402 MWh/year) and non-refurbished buildings (139.6 MWh/year). The LCOH, however, is lowest when booster units are not necessary as the LCOH is mainly driven by the high investment cost of the network and the booster units. This results in a LCOH of 213 €/MWhth for non-refurbished buildings at a network temperature of 75 °C and 297 €/MWhth for refurbished buildings at 55 °C.

What implications do primary energy use, urban population agglomeration, and economic development rendered to Romania's environmental sustainability?

The energy sector plays a significant role in Romania's expanding economic and security agenda. The energy sector utilizes a diverse range of resources, such as renewable energy, nuclear power, coal, and natural gas. Traditionally, the primary sources of the country's energy have been coal and natural gas, while hydroelectricity and nuclear power have played supplementary roles. The present study's major purpose is to establish how primary energy consumption, fossil fuel consumption, urban population agglomeration, and economic growth affect CO2 emissions in Romania. The time series data covering 1990 to 2021 was analyzed using the symmetric Autoregressive Distributed Lag (ARDL) approach in conjunction with robust least squares technique. The study's findings demonstrated that in both the short and long run, variables such as fossil fuel consumption, urban population agglomeration, and economic growth had a positive influence on CO2 emissions. Primary energy consumption has a detrimental influence on environmental quality in Romania. Similarly, the results of the robust least squares technique show that distinct variables have specific effects on environmental quality. It particularly shows that fossil fuel consumption, urban population agglomeration, and economic growth have a positive effect on CO2 emissions. However, empirical evidence indicates that primary energy consumption has a negative impact on CO2 emissions. It is essential for the Romanian government to take more steps to successfully address the problem of environmental degradation inside the country, with the ultimate goal of increasing economic growth.

Hybrid Metaheuristic Algorithms for Optimization of Countrywide Primary Energy: Analysing Estimation and Year-Ahead Prediction

In the present work, India’s primary energy use is analysed in terms of four socio-economic variables, including Gross Domestic Product, population, and the amounts of exports and imports. Historical data were obtained from the World Bank database for 44 years as annual values (1971–2014). Energy use is analysed as an optimisation problem, where a unique ensemble of two metaheuristic algorithms, Grammatical Evolution (GE), and Differential Evolution (DE), is applied. The energy optimisation problem has been investigated in two ways: estimation and a year-ahead prediction. Models are compared using RMSE (objective function) and further ranked using the Global Performance Index (GPI). For the estimation problem, RMSE values are found to be as low as 0.0078 and 0.0103 on training and test datasets, respectively. The average estimated energy use is found in good agreement with the data (RMSE = 6.3749 kgoe/capita), and the best model (E10) has an RMSE of 5.8183 kgoe/capita, with a GPI of 1.7249. For the prediction problem, RMSE is found to be 0.0096 and 0.0122 on training and test datasets, respectively. The average predicted energy use has RMSE of 7.8857 (kgoe/capita), while Model P20 has the best value of RMSE (7.9201 kgoe/capita) and a GPI of 1.8836.

The impact of window opening behavior on the indoor thermal environment and coping strategies in passive houses

China is actively developing passive houses to improve energy efficiency and reduce primary energy use. These buildings have low actual load characteristics, resulting in a smaller air conditioning terminal heating capacity. However, owing to this limited heating capacity, the air conditioning terminal provides modest indoor air regulation. In practice, occupants of passive houses often open windows for ventilation in winter, resulting in an indoor temperature that is lower than the set value, and it takes a long time for the temperature to return to the desired level. There are few studies that have investigated this issue. Two possible solutions to this issue are proposed: first, altering the external wall structure can enhance the thermal response rate, reducing the time needed for temperature recovery. Secondly, limiting the window-opening area can minimize heat loss during ventilation, thereby maintaining a reasonable indoor temperature. Notably, this may inconvenience occupants. Taking a passive house in Qinghai as a case study, this study discusses the influence of window-opening behavior on the indoor thermal environment. Simulations were conducted to study the window-opening behavior considering different window-opening areas and wall structures. Three different wall structures were considered: internal insulation combined with external insulation (IAE), sandwich insulation combined with external insulation (SAE), and external insulation structures. The results indicate that the IAE and SAE structures cannot effectively improve the indoor thermal environment after opening a window. Overall, changing the wall structure does not reduce the time required to restore room temperature. However, by limiting the opening area of the window, the room temperature can be effectively controlled. Under the given window opening ratio, the room temperature can be stabilized above 18 ℃. This study offers a practical method for controlling and enhancing the indoor thermal environment, which is applicable to the construction and development of passive houses.

A multi-criteria decision-making method for thermal insulation material selection in nZEB level questioned affordable multifamily housings

An affordable multifamily housing building archetype project was researched to improve the building envelope’s thermo-physical performance based on thermal insulation configurations to optimize the energy use, life-cycle cost, environmental impact, and thermal comfort with questioning nZEB concept. Five thermal insulation materials as extruded polystyrene (XPS), expanded polystyrene (EPS), rockwool (RW), glass wool (GW), and cellular glass (CG), were studied with four> attribute variations (thermal comfort, density, embodied carbon, and embodied energy) and five thickness variations (0.04, 0.08, 0.12, 0.16, 0.20 m). A total of 100 alternative scenarios> were obtained for the decision-making process, with four performance criteria to be evaluated in terms of energy, cost, thermal comfort, and environmental impact. Equal weights method (EWM), weighted sum method (WSM), and analytical hierarchy process (AHP) were examined for the multi-criteria decision-making among 46 scenariosvel. The analysis beyond the cost-optimal energy efficiency level, which varies between 64.89 and 72.62 kWh/m2a for primary energy use with a potential 10% further reduction, ensures the European Commission’s recommendations that target 50–70 kWh/m2a of primary energy use for housings in the continental climate to achieve nZEB. The best scenarios cover significantly the XPS at the head due to lover investment costs, where RW, GW, and EPS are followed among the best 10 scenarios, respectively. Besides, AHP provides a more effective distribution of weighting factors than the WSM where the best scenarios of the AHP covers 12 cm thermal insulation alternatives by balancing the investment costs and energy efficiency levels. The paper provides insight into thermal insulation material selection while searching for the advantages and priorities of thermal insulation materials’ attributes beyond the cost-optimal energy efficiency level to reach the nZEB range.

Impacts of Global Warming on Regional Energy and Economy: Uneven consequences arising from global warming-induced heating and cooling demand of households

The impacts of global warming vary across regions. This paper studies the distributional implications of global warming impacts on household energy use for heating and cooling and the induced macroeconomic responses under different scenarios. Our research updates the direct impact of global warming on household energy demand in 140 regions worldwide by utilizing existing estimations of damage functions related to temperature changes. Subsequently, the updated direct impact is used in a global static computable general equilibrium (CGE) model to evaluate the macroeconomic responses. We find that at the global level, the market effects cause a reduction in the direct impact on the demand for oil and gas, while that for electricity displays a positive but moderate growth. Whereas the regional effects vary across countries and lead to changes in both directions, in which the autonomous adaptation embodied in the global market plays a vital role. Furthermore, we find strong inequality in the socioeconomic responses to global warming across regions. Notably, low-income countries are most strongly affected by increased primary energy use and decreased gross domestic product (GDP). Disparities in the impacts on carbon-based energy sources yield a near-perfect inequality as per the adjusted Gini index for CO2 emission changes, which potentially intensify the distributional consequences of global climate change.

Exergy analysis and Exergetic sustainability index of package boiler

Energy is one of the basic human needs. Economic growth and population growth in a country which continues to increase is directly proportional to the growth in energy needs required by society. Indonesia is the largest energy user in Southeast Asia, namely more than 36% of Southeast Asia's primary energy use. Utilization of the energy used will reduce the increase in production costs for an industry. The use of energy is better known as energy conservation. Energy and exergy analysis based on the first and second laws of thermodynamics is used to analyze the thermal system of industrial units. This can be applied to equipment units in the fertilizer industry to identify sources of inefficiency, determine their location and the amount of exergy destruction that occur. To reduce exergy destruction, this can be done by modifying the operating conditions of the package boiler. The results show that 94.3% of the total exergy destruction from the boiler package is obtained from the evaporator component with a value of 2.7 x 108 kJ/hr Modification of the operating conditions of the evaporator is carried out by reducing Boiler Feed Water (BFW) inlet temperature with T 100C (196 – 116 oC). The decrease BFW temperature will increase the amount of required latent heat and reduce the convection heat that will be carried by the flue gas to generate superheated steam. Optimization of the BFW temperature is performed be calculating the flue gas temperature and exergoeconomic analysis. Exergoeconomic analysis is performed by calculating the cost rate of exergy destruction (ĊD,k) and exergoeconomic factor (fk). The results obtained were that the temperature was optimum of BFW is at 161°C which resulted the reduction of exergy destruction of 6,2x106 kJ/hr and resulting difference cost losses based on actual data (196 oC) of Rp 1,370,354,743/hr. Exergetic Sustainability Index (ESI) used to demonstrate how reducing a system's environmental impact can be achieved by reducing its exergy consumption (destruction and losses) or increasing its exergetic efficiency. In this research, ESI Value was achieved at 0.918.