Heat Resources Research Articles

Assessment of Sustainable Biomass Energy Technologies in Pakistan Using the Analytical Hierarchy Process

Pakistan is not merely confronting the energy crisis but also dealing with the scarcity of economical technologies for the utilization of energy resources. From the basic resources, renewable energy is one of the considerable resources. Due to environmental issues related to greenhouse gases (GHGs) and air pollution in Pakistan, the other energy resources are constricted. In rural areas, biomass resources are a fundamental need for domestic purposes. The prominent reason for environmental degradation and deforestation is due to ineffective use of such resources. Biomass resources for heating and cooking purposes are abundantly available in rural areas of Pakistan. In this context, this study helps us select the applicable cookstove technologies for the Sindh province for the proper utilization of biomass resources. The AHP (analytical hierarchy process) was used as the central methodology for the cookstove ranking. Concerning its improvement, four main criteria corresponding to 12 sub-criteria were considered for the selection of three cookstove technologies, i.e., traditional cookstoves (TCS), efficient cookstoves (ECS), and biogas cookstoves (BCS). The final decision of the AHP framework exposed the ECS technology as the advantageous technology, followed by the BCS and TCS, respectively. To analyze the results, a sensitivity analysis of the major results has also been carried out, and under the final ranking matrix, the ECS alternative got the highest weightage, nearly 36.56%, based on the developed model.

New Horizons for Geothermal Energy

Abstract The geothermal heat resource is not limited the way fuel or iron or other materials are. But the low efficiency of geothermal power systems is unsatisfying and contributes to often-poor economics. To improve efficiency, engineers could look for a different thermodynamic cycle in the power plant. And, the economics can be improved by developing a facility whereby geothermal heat and electricity is the by-product of a process to produce lithium.

Decarbonisation of heat: Analysis of the potential of low temperature waste heat in UK industries

The UK will need to decarbonise low temperature industrial waste heat (up to ≈250 °C) to achieve net-zero greenhouse gas emission targets. Industrial waste heat production represents an opportunity for reduction in the use of primary fuels used in the production of commodities. Energy inefficient processes in addition to increased emissions raises the cost of plant operation, – an undesirable scenario for both industrial competitiveness and the environment. Less is known about the quantity and potential applications for recovered low temperature industrial waste heat in UK and the quantification and characterisation of the resource can provide the needed impetus for the development and adoption of green technologies to help achieve the 2050 Net-Zero target. In this work the potential magnitude of the low temperature industrial waste heat resource in the UK is analysed by using sector-level energy intensity values for different industries while drawing on corresponding estimates from previous studies in the USA and by closely mapping the UK Standard Industrial Classification (SIC 2007) against sectors in the USA (NAICS [North American Industry Classification System]). The assessment undertaken finds that the recoverable potential of low temperature waste heat up to ≈250 °C could be up to 83.7% of the total estimated waste heat potential in UK industry. Significant opportunities exist in this low temperature range for waste heat recovery actions at individual sites. Research and Development (R&D) into alternative improved methods for waste heat recovery, storage, and use (WHRSU) technologies could also produce significant positive environmental and industrial impact.

Suitability zoning of buried pipe ground source heat pump and shallow geothermal resource evaluation of Linqu County, Shandong Province, China

In response to the environmental call for energy conservation and emission reduction, the development and utilization of shallow geothermal energy (SGE) buried pipe ground source heat pumps (GSHP) in the urban area of Linqu County has been studied. Based on geological data and water quality analysis data, ground temperature monitoring test and field thermal response test research results, using the analytic hierarchy process, the suitability of buried GSHP in the study area is computed by division, heat capacity calculation and resource potential evaluation. The results show that the development and utilization of GSHP in the study area are mainly in the moderately suitable area. The heat capacity within 120 m depth is 3.52 × 1013 kJ/°C, and the heat capacity of 200 m shallow geothermal energy is 5.84 × 1013 kJ/°C. Considering the land use coefficient, the total available heat transfer power of the buried pipe ground source heat pump is 2.56 × 106 kW. The heat transfer power in summer is greater than the heat transfer power in winter. The resource potential of buried pipe ground source heat pump is mainly in the medium potential area, and the development potential is finer in winter than in summer. Generally, the development and utilization of shallow geothermal energy in the urban area of Linqu County have broad pros.

Determining Geothermal Resources in Three Texas Counties

This project updates the geothermal resources beneath our oil and gas fields, as part of the research for the Texas GEO project for the counties of Crockett, Jackson and Webb. Through additional bottom-hole temperatures from oil and gas wells drilled in the late 1990s to 2019, the number of sites increased from 532 to 5,410. The project improved the methodology to calculate formation temperatures from 3.5 km to 10 km, included thermal conductivity values more closely related to the actual county geological formations, and incorporated radiogenic heat production of formations and the related mapped depth to basement. The project results show deep temperatures as hotter than previously calculated, with temperatures of 150 °C possible for Webb County between depths of 2.6 – 5.1 kms, average 3.3 km; Jackson County between depths 3.0 – 5.4 kms, average 3.7 km; and Crockett County between depths of 2.7 – 8.0 kms, average 4.0 km. Based on the 150 °C temperature desired for electrical production, 677 wells or 11.6 % of them have at least this temperature or higher. The oil and gas industry can be a significant resource for unlocking our ability as a nation to extract the geothermal heat resource.

A highly efficient and accurate FE-ROM method for thermal-mechanical buckling of heat transfer panels

Thin-walled panels are commonly used in high-speed aircrafts and space launcher vehicles. These applications often serve in a complex operating environment with the thermal-mechanical coupling loading. The steady-state temperature field eventually produced by the aerodynamic heating should be taken into account when solving the structural elastic deformations. This work proposes a highly efficient and accurate finite element based reduced-order modeling (FE-ROM) method for the thermal-mechanical buckling of heat transfer panels. The classical Koiter asymptotic expansion is reformulated to be applicable for thermal-mechanical buckling problems. The thermal-mechanical reduced-order model is constructed based on the novel Koiter theory. The complex temperature field produced by the heat transfer is skillfully considered in the reduced system. The predictor-corrector scheme based on the reduced system is developed to trace the thermoelastic geometrically nonlinear response. Various flat/curved panels with isotropic/orthotropic materials, are selected to validate the high efficiency and accuracy of the proposed method, considering different thermal-mechanical coupling loads, heat resource locations, geometrical shapes and lamination configurations.

Estimation and prediction of shallow ground source heat resources subjected to complex soil and atmospheric boundary conditions

5th generation district heating and cooling networks operating at near ground temperature offer a low-cost, zero-carbon energy solution. Detailed understanding and accurate estimation of ground behaviour for its heat storage and recharge potential are of paramount importance for the success of such networks. In this paper, an advanced modelling tool, based on a coupled Thermal-Hydraulic (TH) modelling framework, is presented to calculate and predict temperature and soil-moisture behaviour of a shallow ground under complex atmospheric, temperature and hydraulic boundary conditions. Atmospheric data e.g., solar radiation, rainfall, humidity, air temperature, wind velocity is considered together with subsurface soil data to investigate thermal and hydraulic responses of the ground, and its individual soil layers. Furthermore, a transient method for estimating shallow ground source heat (SGSH) resources is proposed based on the simulated temperature and saturation distributions of the ground. The model is applied to predict the long-term ground temperature and saturation level of a test site located in Warwickshire County, UK. The total heat content per unit area and the annual/seasonal/monthly net heat content per unit area of the site are predicted for a five-year period. The total heat content of the sandy clay layer varied between 2.32 and 11.6 MJ/m2, silty clay from 34.0 to 50.5 MJ/m2, and mudstone from 50.7 to 55.0 MJ/m2. A parametric sensitivity study is also conducted to investigate the effects of soil types and hydraulic drainage conditions on the ground heat supply potential, and it revealed that the spatial and temporal distributions of ground heat is significantly affected by the underlying soils. This study highlights the influences of atmospheric conditions and coupled ground processes, and the parameters that should be considered for designing a 5th generation low-temperature heat network.

Water and heat resource utilization of cotton under different cropping patterns and their effects on crop biomass and yield formation

• A new method for visualizing the spatiotemporal change in soil water consumption. • The complexity of crop responses to multiple environmental factors is highlighted. • The main factor driving cotton biomass formation is water consumption. • Cotton yield exhibits a significant positive correlation with PE GDD and PE soil . • MC and WIC had high cotton yield and accumulated temperature production efficiency. In the context of intensified climate change, approximately 70% of global cotton ( Gossypium hirsutum L.) production is in arid or high temperature environments. Improving cultivation practices is an effective measure to promote the adaptation of cotton production to the climate. To comprehensively study the characteristics of the hydrothermal microclimate in cotton fields and their relationship with cotton biomass and yield formation, a grid sampling method based on sensors with high spatiotemporal resolution was used in this study to monitor the soil temperature and soil moisture under three cropping patterns (monoculture cotton (MC), wheat ( Triticum aestivum L.)/delayed intercropped cotton (WIC), and wheat/direct-seeded cotton (WDC)). The cropping patterns substantially changed the cotton hydrothermal resource utilization. WDC was the pattern with low cotton yield and low hydrothermal resource use efficiency, while MC and WIC were the patterns with high cotton yield and high accumulated temperature production efficiency. Cotton yield exhibited a very significant positive correlation with the accumulated temperature production efficiency of air and soil, and these relationships were less affected by different planting patterns. The climate in 2016 was relatively humid, and the water consumption (WC) of MC was mainly concentrated within a soil depth of 70 cm, WIC was 50 cm, and WDC was 30 cm. The climate in 2017 was relatively dry, and the main soil depth ranges of WC in MC, WIC, and WDC were 50, 30, and 20 cm, respectively. WC was the most important factor affecting cotton biomass, especially reproductive organ biomass, followed by the effective accumulated air temperature. The WC of cotton was most affected by changes in soil moisture at a depth of 30 cm. This study strengthens the application of smart agricultural technology in sustainable cotton production and highlights the complexity of crop responses to cultivation practices and multiple environmental factors.

Three-dimensional visualization of thermal environments in urban canyons

Temperature distribution in urban canyons is dynamic, complex, and influenced by a range of heat resources such as radiant heat from reflected sunlight and convective heat from wind flow. While 2D data collection and presentation are the norm for UHI research, we propose using an unmanned aerial vehicle to measure temperatures at different horizontal and vertical locations in urban canyons to develop a 3D visualization of urban thermal environments. We implemented Gestalt laws and transparent and opaque color-coding to improve background recognition and visual closure as well as to better represent the spatiality of temperature data. Our design included grouped color pixels and an interactive temperature slider function. We investigated whether interface usage varied with the flexibility of closure, perceptual speed, and spatial relations of users. Responses from 102 participants indicated that users with flexibility in closure approved of the transparent colors and slider. The primary advantage of this visual model is the elimination of clutter. Visual clutter can cause users to lose their focus when searching a 2D representation of a 3D geographic space. In the proposed model, data hotspots and the boundaries produced by multiple aggregations and clustering enable users to readily and easily find the required information.

MODELING OF THE THERMAL REGIME OF DRAINED PEAT-BOGS SOILS IN BELARUSIAN POLESIE

The article presents the results of modeling predictive estimates of the distribution of heat resources in peat-bog soils at various rates of drainage, taking into account global climate warming for the period up to 2035. The proposed method makes it possible, using mathematical modeling, to obtain the temperature profile of soils, which is the basis for assessing changes in the temperature and thermal regimes of natural and drained soils of Belarusian Polissia due to changes in air temperature. The results obtained in the work can be used in the management of the water regime of reclaimed lands.

Performance assessment of a novel combined heating mode integrated greenhouse and closed drying system with a dual-temperature steam jet heat pump

Waste heat recovery can significantly reduce energy consumption and greenhouse gas emissions in agricultural production. This study proposes a novel combined heating mode (CHM) integrated with a dual-temperature steam jet heat pump (DTJP) system with greenhouse (GH) and closed drying system (CDS) used in agricultural drying. The new system using water vapor as the working fluid significantly improves the performance by utilizing waste heat resources effectively. Compared with the individual heating mode (IHM), the new system reduces the usage of ancillary equipment, land occupancy, initial costs, and underground heat. The coefficient of performance (COP) and annual steam consumption are the main indicators for comparing the CHM using the proposed heat pump system with the IHM using a conventional jet heat pump. The thermodynamic analysis results show that the new system significantly enhances the COP under the given operating conditions. There is a 13–15.8% reduction in the annual steam consumption. This study provides a new idea for applying a jet heat pump system.

Improving the efficiency of using water radiant heating systems.

Now, the issue of protecting the environment and reducing the use of fossil non-renewable energy sources is becoming increasingly important. For modern heating and air conditioning systems, it is imperative to reduce emissions of harmful substances, especially CO2. This can be realized by significantly reducing the use of fossil non-renewable fuels and reconstructing engineering systems to the current level of energy saving. The annual growth in demand for fossil fuels will be reduced through the optimization of substations and heat distribution devices, which is a necessary step for the development of the country's industry and economy. Therefore, today the main task is to increase the energy efficiency of the use of resources and increase the potential of alternative types of energy in combination with modern low-temperature energy-efficient heat distribution systems, one of which is radiant water panels. The article presents the results of improving the method of mounting beam-ceiling fixtures with respect to their orientation in space. The results of numerical calculations indicate the efficiency of mounting the equipment at an angle of 45 degrees, which increases the efficiency by 10% in relation to the 0° orientation. The results of calculations and measurements show that the use of radiant heating in a lateral or longitudinal direction at different angles allows to significantly reduce the cost of energy resources for heating at low temperatures and at the same time not to lose the speed of operation to changes in external temperature parameters. The most effective of the variants of the experiment turned out to be the variant of suspension at an angle of 45°, in which an increase in efficiency by 10% in terms of final temperatures was found, which in turn makes it possible to reduce the use of thermal energy and reduce the amount of necessary equipment in design calculations. At the same time, installation difficulties were not detected.

Municipal solid wastes pyro-gasification using high-temperature flue gas as heating resource and gasifying agent

With the implementation of municipal solid wastes (MSW) source segregation collection policy, the combustible waste components are suitable for pyrolysis treatment to recover value-added energy such as gas or oil. In this research, the volatile compounds from MSW pyrolysis were reformed by the char obtained from the same process and the high-temperature flue gas (HTFG) of 1200 °C was supplying as heating resource and gasifying agent in a tailor-made experimental set-up. The final yields and properties of the syngas, char, and oil after reforming were investigated. Experimental studies showed that the composition of HTFG had a significant influence on the products. As the HTFG being CO2 and its flowrate increased from 0 to 4 L/min/(kgMSW), the energy share in the gas first increased from 8.29 to 15.1 MJ/(kgMSW) with a higher heat value (HHV) of 19.9 MJ/Nm3, then it decreased slightly with a further increase in the flowrate. However, as the HTFG was H2O or the model flue gas (consisting of CO2, H2O, O2 and N2), the higher flowrate always increased the energy share and cold gasification efficiency (CGE) in the gas products. Both CO2 and H2O participated the volatiles’ reforming reactions and enhanced char gasification; while the volatiles’ reforming inhibited char gasification. When the flowrate of the model flue gas increased from 0 to 12.04 L/min/(kgMSW), the oil and char yields decreased and the CGE increased to more than 75%, which was much higher than that from direct air gasification of MSW; moreover, the gas products had much higher HHVs. This research provides a guidance for producing high-quality syngas from the MSW.

Reflection and Transmission in Non-Local Couple Stress Micropolar Thermoelastic Media

We have studied the problem of homogenous, isotropic non-local couple stress micropolar thermoelastic solid in the absence of body forces, couple density and heat resources. The reflection and transmission of waves at the interface of two distinct media have been investigated. It is observed that amplitude ratios of various reflected and transmitted waves are functions of wave number of incident waves and are affected by the non-local parameter of thermoelastic solid.

Development of the District Heating System on the Left Bank of the Daugava River in Riga

Abstract In Latvia, heat supply is provided in three different ways: using district heating (hereinafter – DH), local heating and individual heating systems. Heat energy consumption consists of heat energy consumption for heating, hot water and heat energy technological processes. The structure of DH consumers has not changed in recent years and the largest consumers of heat are households – 70 % of the total energy consumption. The district heating system accounts for approximately 29 % of the total consumption. There is also the so-called tertiary sector, which is made of municipal and state buildings with a minor total heat consumption of about 1 %. It should be noted that 65–70 % of energy is used for heating needs, and 30–35% for hot water preparation. In Latvia, heat of DH consumers is produced both in boiler houses (hereinafter – BHs) and cogeneration plants (hereinafter – CHPs). The latter also produce electricity. Over the past 10 years, the distribution of heat produced in BHs and CHPs has changed significantly. The heat supply of the Latvian energy sector is a system consisting of three main elements – heat source, transmission and distribution networks, and end consumer. Low efficiency of heat supply system elements creates risks to security of heat supply, resource sustainability and competitiveness. Increasing energy efficiency in the system as a whole, or in individual elements of the system, will promote the enhancement of the heat supply sector, while promoting economic growth as well. The research attempts to evaluate the energy efficiency of DH systems in the so-called left bank (hereinafter – LB) DH area (located on the left bank of the Daugava River in Riga).

Heat Generation and Temperature Rise Characteristics of Single Overcharged Lithium-Ion Batteries

It’s critical to quantitatively investigate the thermal characteristics of single overcharged lithium-ion batteries to realize security alert before thermal runaway occurs. In this work, various (LiCoO2 + LiMn2O4)/graphite soft pack cells overcharged under different cut-off voltages, temperatures and C-rates are tested electrochemically to calculate the heat generation rate and distinguish the dominating heat resource. The results show that overcharged cells with higher cut-off voltage, overcharge temperature and the lower overcharge C-rate exhibit higher heat generation and temperature rise rate as well as poorer state of healthy. Among nonexplosive tested cells, the cell overcharged to 4.8 V at 0.1 C rate and 40 °C exhibits the highest heat generation and temperature rise rates of 9.17 W·l−1 and 4.60 °C·h−1 during 1 C charging at 25 °C. For overcharged cells, lithium plating, increased resistance and gas generation are observed, which are the reason for the accelerated total heat generation rate compared to baseline cells. Comparing with reversible heat, the irreversible heat resulting from diffusion overpotential and the sum of ohmic and charge transfer overpotential is dominating for overcharged cells working under high current. It’s recommended to comprehensively monitor the temperature change of each cell of battery pack.

Sustainable Development of Energy, Water and Environmental Systems and Smart Energy Systems

This 34th volume of the International Journal of Sustainable Energy Planning and Management includes papers from the 2021 conference on Sustainable Development of Energy, Water and Environmental Systems (SDEWES) held October 10-15, 2021, in Dubrovnik, Croatia as well as the 7th International Conference on Smart Energy Systems held September 21-22 in Copenhagen, Denmark and two normal papers. A focus area of this issue is district heating and district cooling systems, with articles addressing resources for district heating and cooling systems, impacts of having individual district heating metres for consumers and approaches to analysing district heating systems. Another focus area is stakeholder involvement where two groups of researchers focus on stakeholders from an energy island perspective as well as from a positive energy district perspective. Both groups note the importance of factoring in stakeholders when devising transition plans. Plans for increasing the penetration of renewable energy sources for the Estonian, Latvia and Lithuanian systems are analysed using the Backbone model, finding modest increases in system costs. Lastly, an article sets up an indicator system for assessing environmental performance of European Union member states ranking, e.g., Estonian, Latvia and Lithuanian as moderate (Estonia and Latvia) to weak (Lithuania) in terms of sustainable energy performance score, based on 2019 data.

Significance of convective Nield's conditions on radiative Casson nanomaterial flow over a bidirectional stretching surface with Arrhenius energy

Attracted by innumerable uses of non-linear nanoscience in renewable energy and pollution cleaning, we articulate a precise model for the unsteady bidirectional flow of Casson nanoliquid, impinging over a deformable surface with a magnetic environment. Aspects of non-linear thermal radiation and Arrhenius energy are accounted for through a two-phase nanofluid model. Moreover, the additional features of Nield’s condition, prescribed surface temperature, convective heating and binary chemical reaction are also used to make the current continuation quite versatile. The modeled problem has been distracted into dimensionless form by combining suitable variables. The numerical solution has been developed to implement the Keller-Box approach with the desired accuracy. The results are analysed through various graphs and tables with physical interpretation. It is scrutinised through the present exploration that the intensifying choices of Biot factor, temperature ratio, and radiation factor augment the distributions of temperature plus concentration, whereas the opposite trend is achieved with the escalation in the choices of heat distribution indices. In view of obtained computations, it seems that the stated results can be used to improve heat and energy resources.

Analysis of climate change impact on resource intensity and carbon emissions in protected farming systems using Water-Energy-Food-Carbon Nexus

As the uncertainty and importance of securing resources increase, the nexus concept is used for integrated sustainable use management planning. In particular, because protected farms are most affected by temperature change, the connection between the heating temperature variable and resources must be analyzed. In this study, a water-energy-food-carbon nexus model that reflected the agricultural characteristics of protected farms was constructed. The crop yield, irrigation amount, and heating energy were simulated, and a sensitivity analysis was performed according to climate change scenarios and heating temperature variables. There was no significant decrease in the yield of food resources even at heating temperatures lower than 12 °C. In contrast, the growing period shortened as the heating temperature increased above 12 °C, which decreased the irrigation amount but tended to increase the heating energy. In addition, lowering the heating temperature standard from 12 °C to 8 °C (or less) is suitable for efficient resource management.

Karakteristik Fluida Panas Bumi Menggunakan Geoindikator Cl-Li-B di Daerah Desa Bakan

Geothermal is a natural heat resource that comes from the interaction between hot rock and water. The results of these interactions are trapped in a place called a geothermal reservoir. North Sulawesi is an area that has geothermal potential, one of which is in Bakan, Bolaang Mongondow, geothermal potential here is a manifestation of hot springs. The purpose of this study was to determine the characteristics of geothermal fluids in the Bakan Village area, using the Cl-Li-B geoindicator method. The use of the Cl-Li-B geoindicator results in Cl being more dominant than Li and B indicating that hot water coming from a heat source that rises to the surface is a fluid originating from a heat source with little cooling, a low B/Li ratio indicates that the fluid zoning is in the upflow zone.