Search Results (17)

Despite Mozambique’s substantial natural gas reserves, most households rely on solid biomass for cooking, with serious consequences for public health, livelihoods, and the environment. The domestic use of these resources could improve energy efficiency, security, and sustainable development. This mixed-methods study uses household interviews, descriptive statistics, multinomial, and conditional logit models, analyzing data from a random survey of 434 households in energy-rich peripheries of northern Inhambane and Maputo City to ascertain the determinants of household cooking energy choice. Results reveal that rising income increases the odds of choosing electricity, LPG, and biomass over natural gas. In energy-rich peripheries, the odds of selecting biomass over natural gas are reduced by 96.2% compared to non-energy-rich regions. Educational and urban habitation are positively correlated with the adoption of electricity and liquefied petroleum gas (LPG). Price serves as a significant negative predictor of fuel selection (OR ≈ 0.000001), whereby each unit increase in price per GJ substantially diminishes the likelihood of opting for alternatives over domestic gas. Monthly fuel expenditure positively predicts electricity, LPG, and biomass adoption (OR = 1.0042), with effects accumulating meaningfully across realistic spending ranges. Households that experienced energy system incidents were more than twice as likely to switch away from natural gas (OR = 2.072), reflecting the critical role of infrastructure reliability in fuel choice. Given natural gas’s potential as a clean cooking transition fuel, the government should prioritize investment in gas infrastructure, expand domestic supply, and promote public awareness of the health and environmental benefits of clean cooking energy. Full article

Biogas produced from the anaerobic digestion of organic matter holds much promise as a renewable energy source for decentralized systems. However, raw biogas contains substantial volumes of carbon dioxide, hydrogen sulfide, water vapor, and other trace impurities. These impurities can reduce the calorific value of biogas and limit its direct use for household energy needs. Purifying biogas to high-grade biomethane (≥95%) is therefore important to improve methane (CH₄) content and combustion characteristics. This is a guarantee of its safe utilization in domestic appliances, including cooking, heating, lighting, and electricity generation. This article reviews and evaluates novel approaches for upgrading raw biogas into high-purity biomethane that can offset natural gas in domestic applications. It further examines recent developments in conventional and innovative upgrading technologies such as water scrubbing, chemical scrubbing, pressure swing adsorption, membrane separation, cryogenic separation, and biological upgrading. Particular emphasis is placed on low-cost and small-scale solutions suitable for off-grid or mini-grid rural energy systems. Moreover, the role of process optimization, intelligent monitoring, and data-driven control methods in increasing CH₄ recovery and process efficiency is discussed. Despite their relatively high capital costs and energy needs, conventional technologies such as water scrubbing, pressure swing adsorption, and membrane technology continue to dominate biogas purification systems. The findings show that coupling advanced separation technologies, including cryogenic separation, biological upgrading, and hybrid technologies, with optimized process control can significantly improve CH₄ purity, save energy use, and enhance the overall consistency of biogas purification systems. These innovative strategies have strong potential to promote the full-scale adoption of biomethane as a clean, sustainable, and affordable energy source for decentralized applications, particularly in the developing world. Full article

Rural households in cold regions still rely heavily on coal for cooking and domestic hot water, while single renewable energy sources suffer from intermittency and limited system-level assessment. This study proposes a solar–biogas complementary energy supply system integrating evacuated-tube solar collectors, an above-ground anaerobic digester, thermal storage, and biogas utilization for rural residential applications in Minqin, Northwest China. A dynamic system-wide model was developed by coupling TRNSYS with nonlinear representations of anaerobic fermentation and biogas boilers, enabling hour-by-hour simulation of energy production, conversion, storage, and consumption. Field measurements were used for validation, and the root mean square deviation between simulated and measured temperatures and gas production remained below 10%. During the heating season, the solar subsystem supplied 10% of the digester heating demand and 90% of the domestic hot-water load, while the biogas subsystem contributed 9.29% and 90.71%, respectively. The system delivered 4728.96 MJ of heat against a seasonal demand of 4636.22 MJ, fully meeting user requirements. A comprehensive 3E (energy–environment–economic) assessment shows that, compared with traditional rural energy supply modes, the proposed system reduces CO₂ and NOx emissions by 65.85% and 98.13%, respectively, and demonstrates favorable economics with a benefit–cost ratio of 2.41 and a discounted payback period of 3.27 years. The proposed modeling and evaluation framework provides a replicable solution for clean energy substitution and circular waste utilization in rural areas. Full article

There is still a need to develop scenarios and models aimed at substituting fuelwood and reducing the use of fossil fuels such as liquefied petroleum gas (LPG), on which low-income rural households in the Global South often depend. The use of these fuels for cooking and heating in domestic and productive activities poses significant health and environmental risks. This study validated, in three different phases, the sustainability of a model for the production and use of biogas from the treatment of swine-rearing wastewater (WWs) on a community farm: (i) A Multi-Criteria Analysis (MCA), incorporating environmental, social/health, technical, and economic criteria, identified the main weighted criterion to C8 (use of small-scale technologies and low-cost access), with a score of 0.44 points, as well as the Tubular biodigester (Tb) as the most suitable option for the study area, scoring 8.1 points. (ii) Monitoring of the Tb over 90 days showed an average biogas production of 2.6 m³ d⁻¹, with average correlation 0.21 m³ Biogas kg Biomass⁻¹. Using the experimental biogas production rate (k = 0.0512 d⁻¹), the process was simulated with the BgMod model, achieving an average deviation of only 10.4% during the final production phase. (iii) The quantification of benefits demonstrated significant reductions in firewood use: in Scenario S1 (kitchen energy needs), biogas replaced 83.1% of firewood, while in Scenario S2 (citronella essential oil production), the substitution rate was 24.1%. In both cases, the avoided emissions amounted to 0.52 tons of CO_2eq per month. Finally, this study proposes a synthesised, community-based rural biogas framework designed for replication in regions with similar socio-environmental, technical, and economic conditions. Full article

The use of sustainable energy sources is an alternative for fossil fuels, which can represent a positive factor to alleviate many current environmental issues. In that sense, not only sustainable industrial development is important, but also sustainable practices at the local level, including households. Specifically, heating and cooking are one of the most important activities that require energy in households, where the role of biomass could be of interest, as it can provide an energy source with lower environmental impact. However, there is room for improvement in biomass stoves, whose adaptability to specific wastes, as well as their improvement in efficiency, should be accomplished. The aim of this work was to assess the improvement of combustion performance of a domestic stove by the implementation of a programmable logic converter for a better adaptation to different biomass samples (holm oak, pear tree, poplar, and sugarcane bagasse pellets). This work provides further information about the current working protocol, being an alternative for better approaches that could be implemented in future works. Thus, the working regime of the stove was controlled, especially concerning the screw conveyor (to regulate pellet feeding) and flue gas fan (to change oxygen supply). As a result, better combustion performances were obtained, with heat capacities from 5.66 to 8.67 kW for the selected samples. Also, thermal capacities of the stove (1.43, 1.60, 2.22, and 1.83 kW for holm oak, pear tree, poplar, and sugarcane bagasse, respectively) were obtained, with a better combustion performance compared to previous studies (1600 and 120 ppm peak emissions for CO and NO_x, respectively, and 15% as the lowest O₂ concentration). On the other hand, different improvements of the combustion stove to avoid blockages, for instance, are proposed as further steps. Full article

The consumption of “ready-to-cook” foods has been experiencing rapid expansion due to modern lifestyles, and they are often sold in economical multipacks. These foods necessitate packaging that maintains their quality for extended periods of time during home storage once the original packaging is opened. This study evaluates a chitosan-based film derived from low- and high-molecular-weight (MW) chitosan in acetic acid without synthetic additives as an alternative packaging material for “ready-to-cook” beef burgers. The burgers were stored at 8 °C after being removed from their sales packaging. A commercial polyethylene (PE) film designed for food use, devoid of polyvinylchloride (PVC) and additives, served as the reference material. The production of six biogenic amines (BAs), indicative of putrefactive processes, was monitored. Additionally, the release of four phthalates (PAEs), unintentionally present in the packaging films, was assessed using solid-phase microextraction coupled with gas chromatography/mass spectrometry (SPME-GC/MS). Microbiological tests were conducted to investigate the antimicrobial efficacy of the packaging against Aspergillus Niger NRR3112. The results showed that the chitosan-based films, particularly those with low MW (LMW), exhibited superior meat preservation compared to the PE films. Furthermore, they released PAEs below legal limits and demonstrated the complete inhibition of fungal growth. These findings highlight the potential of chitosan-based packaging as a viable and effective option for extending the shelf-life and maintaining the quality of “ready-to-cook” meat products during domestic storage. Full article

Air pollution forecasting systems are useful tools for the reduction in human health risks and the eventual improvement of atmospheric quality on regional or urban scales. The SmartAQ (Smart Air Quality) forecasting system combines state-of-the-art meteorological and chemical transport models to provide detailed air pollutant concentration predictions at a resolution of 1 × 1 km² for the urban area of interest for the next few days. The Weather Research and Forecasting (WRF) mesoscale numerical weather prediction model is used to produce meteorological fields and the PMCAMx (Particulate Matter Comprehensive Air quality Model with extensions) chemical transport model for the simulation of air pollution. SmartAQ operates automatically in real time and provides, in its current configuration, a three-day forecast of the concentration of tens of gas-phase air pollutants (NO_x, SO₂, CO, O₃, volatile organic compounds, etc.), the complete aerosol size/composition distribution, and the source contributions for all primary and secondary pollutants. The system simulates the regional air quality in Europe at medium spatial resolution and can focus, using high resolution, on any urban area of the continent. The city of Patras in Greece is used for the first SmartAQ application, taking advantage of the available Patras’ dense low-cost sensor network for PM_2.5 (particles smaller than 2.5 μm) concentration measurements. Advantages of SmartAQ include (a) a high horizontal spatial resolution of 1 × 1 km² for the simulated urban area; (b) advanced treatment of the organic aerosol volatility and chemistry; (c) use of an updated emission inventory that includes not only the traditional sources (industry, transport, agriculture, etc.), but also biomass burning from domestic heating and cooking; (d) forecasting of not only the pollutant concentrations, but also of the sources contributions for each one of them using the Particulate matter Source Apportionment Technology (PSAT) algorithm. Full article

Low-temperature solar thermal energy is a viable and mature alternative to reduce the use of fossil fuels for domestic hot water heating. The impact of the inclusion of this technology in the energy matrix in the Andean city of Cuenca, Ecuador, is analyzed. In Ecuador, liquefied petroleum gas (LPG) is currently used to heat water due to the high state subsidy, with a cost of 0, 11 USD for an LPG kg compared to the international price of 1.18 USD a Kg of LPG in 2021. Sustainability indicators show that the urban energy matrix would be minimally affected by a high penetration of solar thermal systems. The indicators that are positively affected are related to energy self-sufficiency, emissions, and employment at the expense of an increase in the cost of energy. Moreover, the analysis of the impact on consumption exclusively in the residential sector shows that liquefied petroleum gas consumption would drop from 73 to 64%, mainly because the liquefied gas is used in cooking. However, the change in technology is limited by the subsidized cost of liquefied petroleum gas, which makes the adoption of this technology difficult in the current state Full article

Thermoelectric generators are devices that harvest waste heat and convert it into useful power. They are considered as an additional power source in the domestic sector, but they can also be installed in off-grid objects. In addition, they are a promising solution for regions where there is a lack of electricity. Since biomass heating and cooking stoves are widely used, it is very appropriate to integrate thermoelectric generators with wood-fired stoves. This paper shows the experimental analysis of a micro-cogeneration system equipped with a wood-fired stove and two prototypical constructions of thermoelectric generators dedicated to mounting on the flue gas channel. The first version was equipped with one basic thermoelectric module and used to test various cooling methods, while the second construction integrated four basic thermoelectric modules and a water-cooling system. During the tests conducted, the electricity generated in the thermoelectric generators was measured by the electronic load, which allowed the simulation of various operating conditions. The results obtained confirm the possibility of using thermoelectric generators to generate power from waste heat resulting from the wood-fired stove. The maximum power obtained during the discussed combustion process was 15.4 W (if this value occurred during the entire main phase, the energy generated would be at a level of approximately 30 Wh), while the heat transferred to the water was ca. 750 Wh. Furthermore, two specially introduced factors (CPC and CPTC) allowed the comparison of developed generators, and the conclusion was drawn that both developed constructions were characterized by higher CPC values compared to available units in the market. By introducing thermoelectric modules characterized by higher performance, a higher amount of electricity generated may be provided, and sufficient levels of current and voltage may be achieved. Full article

Background: In low- and middle-income countries (LMICs), household air pollution as a result of using solid biomass for cooking, lighting and heating (HAP) is associated with respiratory infections, accounting for approximately 4 million early deaths each year worldwide. The majority of deaths are among children under five years. This population-based cross-sectional study investigates the association between solid biomass usage and risk of acute respiratory infections (ARI) and acute lower respiratory infections (ALRI) in 37 LMICs within Africa, Americas, Southeast Asia, European, Eastern Mediterranean and Western Pacific regions. Materials and methods: Using population-based data obtained from Demographic and Health surveys (2010–2018), domestic cooking energy sources were classified solid biomass (wood, charcoal/dung, agricultural crop) and cleaner energy sources (e.g., Liquid Petroleum Gas (LPG), electricity, biogas and natural gas). Composite measures of ARI (shortness of breath, cough) and ALRI (shortness of breath, cough and fever) were composed using maternally reported respiratory symptoms over the two-week period prior to the interview. Multivariable logistic regression was used to identify the association between biomass fuel usage with ARI and ALRI, accounting for relevant individual, household and situational confounders, including stratification by context (urban/rural). Results: After adjustment, in the pooled analysis, children residing in solid biomass cooking households had an observed increased adjusted odds ratio of ARI (AOR: 1.17; 95% CI: 1.09–1.25) and ALRI (AOR: 1.16; 95% CI 1.07–1.25) compared to cleaner energy sources. In stratified analyses, a comparable association was observed in urban areas (ARI: 1.16 [1.06–1.28]; ALRI: 1.14 [1.02–1.27]), but only significant for ARI among those living in rural areas (ARI: 1.14 [1.03–1.26]). Conclusion: Switching domestic cooking energy sources from solid biomass to cleaner alternatives would achieve a respiratory health benefit in children under five years worldwide. High quality mixed-methods research is required to improve acceptability and sustained uptake of clean cooking energy source interventions in LMIC settings. Full article

Currently, the use of fossil fuels is very high and existing nature reserves are rapidly depleted. Therefore, researchers are turning their attention to find renewable fuels that have a low impact on the environment, to replace these fossil fuels. Biogas is a low-cost alternative, sustainable, renewable fuel existing worldwide. It can be produced by decomposition of vegetation or waste products of human and animal biological activity. This process is performed by microorganisms (such as methanogens and sulfate-reducing bacteria) by anaerobic digestion. Biogas can serve as a basis for heat and electricity production used for domestic heating and cooking. It can be also used to feed internal combustion engines, gas turbines, fuel cells, or cogeneration systems. In this paper, a comprehensive literature study regarding the laminar burning velocity of biogas-containing mixtures is presented. This study aims to characterize the use of biogas as IC (internal combustion) engine fuel, and to develop efficient safety recommendations and to predict and reduce the risk of fires and accidental explosions caused by biogas. Full article

Rural sanitation is still a challenge in developing countries, such as Brazil, where the majority population live with inadequate services, compromising public health and environmental safety. In this context, this study analyzed the demographic density of these rural agglomerations using secondary data from the Brazilian Institute of Geography and Statistics (IBGE). The goal was to identify the possibilities associated with using small-scale upflow anaerobic sludge blanket (UASB) reactors for sewage treatment, mainly focusing on biogas production and its conversion into energy for cooking, water heating and sludge sanitization. Results showed that most rural agglomerations lacking the appropriate sewage treatment were predominant from 500 to 1500 inhabitants in both northern and southern Brazilian regions. The thermal energy available in the biogas would be enough to sanitize the whole amount of sludge produced in the sewage treatment plants (STPs), producing biosolids for agricultural purposes. Furthermore, the surplus of thermal energy (after sludge sanitization) could be routed for cooking (replacing LPG) and for water heating (replacing electricity) in the northern and southern regions, respectively. This would benefit more than 200,000 families throughout rural areas of the country. Besides the direct social gains derived from the practice of supplying biogas for domestic uses in the vicinity of the STPs, there would be tremendous indirect gains related to the avoidance of greenhouse gas (GHG) emissions. Therefore, an anaerobic-based sewage treatment may improve public health conditions, life quality and generate added value products in Brazilian rural areas. Full article

Tea is the second most consumed beverage globally, yet its environmental implications are largely unknown. To overcome this knowledge gap, life-cycle analysis was conducted aiming to quantify the environmental impacts associated with tea production and consumption. To achieve this objective, Oolong tea production in Taiwan was selected to investigate the life-cycle impact in global warming potential (GWP) and eutrophication potential (EP) associated with one serving of hot tea consumed in Taiwan domestically and the international market in the U.S. and U.K. The results indicate that each serving of Oolong tea can result in a total of 28.6 g CO₂-equivalent of GWP and 0.09 g N-equivalent of EP. Over 52% of GWP and 44% of EP are associated with the tea’s cultivation, in which the application and production of agrochemicals accounts for 90% of GWP and 98% of EP. International consumption can increase GWP and EP by 19% and 26%, respectively, which is largely attributable to the change of cooking energy from natural gases to an electric-gas mixed scheme. The findings from this study articulate the environmental portfolio of Oolong tea. More importantly, we can identify opportunities to mitigate the environmental footprint of Oolong tea in order to advance future sustainability. Full article

Solid fuel cooking stoves have been used as primary energy sources for residential cooking and heating activities throughout human history. It has been estimated that domestic combustion of solid fuels makes a considerable contribution to global greenhouse gas (GHG) and pollutant emissions. The majority of data collected from simulated tests in laboratories does not accurately reflect the performance of stoves in actual use. This study characterizes in-field emissions of fine particulate matter (PM_2.5), carbon dioxide (CO₂), carbon monoxide (CO), methane (CH₄), and total non-methane hydrocarbons (TNMHC) from residential cooking events with various fuel and stove types from villages in two provinces in China (Tibet and Yunnan) in the Himalayan area. Emissions of PM_2.5 and gas-phase pollutant concentrations were measured directly and corresponding emission factors calculated using the carbon balance approach. Real-time monitoring of indoor PM_2.5, CO₂, and CO concentrations was conducted simultaneously. Major factors responsible for emission variance among and between cooking stoves are discussed. Full article

Background: There is evidence that household air pollution is associated with poor health in China, and that this form of air pollution may even be more of a health concern in China than the much-publicized outdoor air pollution. However, there is little empirical evidence on the relationship between household air pollution and health in China based on nationally representative and longitudinal data. This study examines the association between the type of domestic cooking fuel and the health of women aged ≥16 in rural China. Methods: Using longitudinal and biomarker data from the China Family Panel Studies (n = 12,901) and the China Health and Nutrition Survey (n = 15,539), we investigate the impact of three major domestic cooking fuels (wood/straw, coal, liquefied petroleum gas (LPG)) on health status using both cross-sectional and panel approaches. Results: Compared to women whose households cook with dirty fuels like wood/straw, women whose households cook with cleaner fuels like LPG have a significantly lower probability of chronic or acute diseases and are more likely to report better health. Cooking with domestic coal instead of wood or straw is also associated with elevated levels of having certain risks (such as systolic blood pressure) related to cardiovascular diseases. Conclusions: Our study provides evidence that using cleaner fuels like LPG is associated with better health among women in rural China, suggesting that the shift from dirty fuels to cleaner choices may be associated with improved health outcomes. Full article