Effect of photovoltaic installation power and façade glazing ratio on the energy performance of a nursery building

PurposeThe aim of the research is to determine the influence of photovoltaic (PV) installation and the share of façade glazing on the energy profile of nursery buildings in the Baltic Sea region, as well as defining the most favorable configuration in terms of energy efficiency.Design/methodology/approachThe article provides comparative calculations of energy performance indicators (Ep, Ed, Eu) and CO2 emissions (mCO2) made for the defined model of the nursery. It includes calculations concerning energy performance of the building, depending on its PV power (0–60 kWp), PV efficiency (100 and 85%) and façade glazing ratio (GR = 25%, 50% and 75%).FindingsThe results of the research indicate that an increase in the PV power exerts proportional impact on the reduction of the Ep and Ed indicators, as well as on the CO2 emissions. Only low GR values (25%) reduce the Eu indicator significantly. Decrease in high range of GR values (over 50%) does not provide proportional effects. In the variant: 60 kWp (100% efficiency) with GR = 25%, the biggest share (99.5%) of RES was obtained. This proves that the concept of energy independent nursery buildings is feasible and reasonable in the examined location.Practical implicationsDesigning buildings towards environmental neutrality requires laborious pre-design conceptual work before developing the right solutions. The set of results of the relationship between the variables of the building's envelope, energy performance indicators and the required involvement of active RES installations to achieve high energy performance of a building presented in the article is valuable. It allows for a preliminary decision of the direction of the design solutions selection in the design process of public utility buildings, such as nurseries. Thus, it may significantly shorten the pre-design analysis process for the location of the southern part of the Baltic Sea region.Originality/valueThe novelty of the paper relies on examining the dependences between PV power and façade glazing ratio in terms of their influence on energy profile of nursery buildings.

Partial Least Squares Regression Approach in the Analysis of Damage Intensity Changes to Prefabricated RC Buildings during the Long Term of Mining Activity

This article presents the results of the analysis of the extent of damage to 138 multi-storey buildings with reinforced concrete prefabricated structure, which are located in the mining terrain of the Legnica-Głogów Copper District. These objects are residential and public utility buildings of up to 43 years old, erected in industrialized prefabricated technologies: large-block and large-panel systems. The research was based on the results of technical condition inventory carried out in 2002, 2007 and 2012. As part of the analysis, the damage intensity index wu was established for individual structural and finishing elements of the studied buildings. This index is defined on a six-point scale, which includes a detailed description of the extent of damage that corresponds to the successive degrees of intensity. As part of the research, the databases were significantly expanded and the generalized formulas of the damage intensity index wu for individual groups of buildings were verified. For this purpose, the partial least squares regression (PLSR) method was applied. Thereafter, the analysis of changes of this intensity in time was carried out and the relations between the extent of damage and the impacts of mining exploitation were examined. The approach presented in this paper and obtained research results are characterized by a high degree of utilitarianism and can be applied to increase the efficiency in the optimal maintenance management of buildings, including planning of repairs and retrofits throughout the technical life cycle of the buildings.

Lighting conditions as the occupational health related issue – case study

The paper deals with the important element of proper lighting conditions at a workplace. The case study has been focused on the intelligent building “Energis” of Kielce University of Technology, where the experimental tests took place. Several groups of volunteers filled in the questionnaires related to their subjective feelings of lighting conditions in lecture rooms at different seasons. Simultaneously, precise measurements of lighting intensity were carried out. The comparison of the expressions of the room users and the measurements enabled to draw conclusions about the conditions provided in the intelligent building related to lighting. The study provides valuable information of lighting conditions in the modern, intelligent buildings which are more and more common throughout the world and serve various purposes such as office, educational or other public utility buildings.

The effectiveness of China’s regional carbon market pilots in reducing firm emissions

China has implemented an emission trading system (ETS) to reduce its ever-increasing greenhouse gas emissions while maintaining rapid economic growth. With low carbon prices and infrequent allowance trading, whether China’s ETS is an effective approach for climate mitigation has entered the center of the policy and research debate. Utilizing China’s regional ETS pilots as a quasi-natural experiment, we provide a comprehensive assessment of the effects of ETS on firm carbon emissions and economic outcomes by means of a matched difference-in-differences (DID) approach. The empirical analysis is based on a unique panel dataset of firm tax records in the manufacturing and public utility sectors during 2009 to 2015. We show unambiguous evidence that the regional ETS pilots are effective in reducing firm emissions, leading to a 16.7% reduction in total emissions and a 9.7% reduction in emission intensity. Regulated firms achieve emission abatement through conserving energy consumption and switching to low-carbon fuels. The economic consequences of the ETS are mixed. On one hand, the ETS has a negative impact on employment and capital input; on the other hand, the ETS incentivizes regulated firms to improve productivity. In the aggregate, the ETS does not exhibit statistically significant effects on output and export. We also find that the ETS displays notable heterogeneity across pilots. Mass-based allowance allocation rules, higher carbon prices, and active allowance trading contribute to more pronounced effects in emission abatement.

Justice and inequality in the household consumption in Russia and China: A comparative analysis

The authors conducted a comparative analysis of the household consumption in Russia and China on the basis of the reputable empirical information sources. The article focuses on the main trends and peculiarities in how households from each country differed in terms of the structure and level of consumption under dramatic transformations associated with market reforms. Inequality in consumption in Russia and China, which can be characterized as high or excessive, largely determines the overall situation with social inequality and significantly influences the development of state social policy in various fields. As for the most differentiating items of expenditure for both countries, those are groceries, durable goods, public utility payments, cultural activities and entertainment. After noting the effect that income has on consumption, which is undeniable, though differs in nature and degree, the authors focus on other factors of this type of inequality, in particular, on the territorial, regional and settlement-specific characteristics of consumption inequality in both countries. The authors argue that in Russia, there is significant regional inequality in consumption, while in China such inequality is more settlement-specific; there are also differences in consumption inequality between urban and rural areas, which contribute to the overall situation with social inequality. In China, urban household expenditures are growing much faster than those of rural households, while in Russia the difference is not that pronounced. That said, the share of spending on groceries in the structure of expenditures is decreasing more rapidly in urban China, and compared to Russia, there is a smaller gap between urban and rural areas. At the same time in China, consumption inequality as a result of age and class differences is a much more acute issue, while in Russia, the differences caused by intensifying economic stratification seem to be a more important factor of inequality.

Causes of road projects' delays: a case of Blantyre, Malawi

PurposeThe study aims to find the causes of road projects implementation delays in Blantyre, one of the four city councils (CCs) in Malawi.Design/methodology/approachThe study followed a qualitative research approach using a Blantyre City Council (BCC) as a case study. This study combined in-depth, face-to-face interviews with councillors, secretariat staff, consultants, and contractors who worked on the city's road projects. Data gathered were analysed using thematic content analysis. Also, some road project documents were examined.FindingsThe findings from the case study revealed the primary cause of road project construction delays as the shortage of engineers in conducting detailed proposed projects surveys resulting in incomplete project scope definition before contractor's procurement. Other identified factors were service providers delaying the removal of existing public utility infrastructure from project sites, client funding issues, scope changes, and client delays in issuing instructions to the contractors during project implementation. Another factor was the shortage of construction equipment and construction materials experienced by some appointed contractors.Research limitations/implicationsOnly road construction projects and stakeholders operating from Blantyre city, Malawi, were contacted for the study; thus, the findings may not be generalizable.Practical implicationsThere is an urgent need to increase technical employees, especially engineers and other critical technical staff such as quantity surveyors in Blantyre. Employees' conditions of service should be conducive to attract qualified people to undertake effective management and assessment of projects before commencement to identify the feasibility of proposed projects to decrease the rate of road construction project delays.Originality/valueThe study has established Blantyre city's core challenges in implementing its road projects seamlessly and has provided mitigation measures for dealing with the shortcomings.

Users’ Sensations in the Context of Energy Efficiency Maintenance in Public Utility Buildings

Research towards understanding the relationship between maintaining thermal comfort and energy efficiency in the public utility buildings was undertaken among 323 1st year students during class hours. Questionnaires surveys and measurements of indoor conditions were performed. The article identified students’ sensations and perceptions concerning indoor conditions. Temperature, relative humidity, air velocity and CO2 concentration measured to assess room conditions showed that the auditorium had almost comfortable conditions according to the literature guidelines. The indices used to assess students’ perceptions were: Thermal Sensation Vote (TSV), Thermal Preference Vote (TPV), Air Freshness Sensation Vote (AfSV), Air Movement Preference Vote (AmPV), and Relative Humidity Preference Vote (RHPV). The interpretation of these indicators showed that while the students’ requests for temperature changes and increased air movement are adequate for the air conditions in the room, the evaluation of stuffiness and requests for changes in humidity levels are surprising. Striving uncritically to meet the desired room parameters, according to the users votes, can lead to deterioration of the air and not only the increase in energy consumption but even waste it. Better understanding of users’ preferences and behaviour and further application of this knowledge indirectly aim at increasing energy efficiency in buildings.

Techno-economic study of a hybrid power generation system at the Lebanese coastal highways

<span lang="EN-US">Despite its great importance in daily life, electricity remains one of the most critical issues in Lebanon where the power supply has been erratic for years and the government faces numerous problems in buying foreign currency for fuel import from petroleum countries. Therefore, there is an urgent need for efficient solutions to produce local energy in a more sustainable way, leading to an environmentally friendly energy consumption, far away from conventional energy sources. In this work, unconventional technologies are used for the generation of clean energy from a system of <a name="_Hlk89670789"></a>photovoltaic (PV) panels and wind turbines. The novelty lies in the fact that the cost of the land required for the installation is almost zero. The middle of the highways is usually left unoccupied and therefore suitable for the project. Another innovative feature of the proposed system is its ability to be connected to the public utility without the need for battery storage, which reduces the total cost of the system. The proposed design consists of 87,750 PVs arranged in pairs on a steel frame for a coastal distance of 117,000 meters (highway distance between Tyre and Tripoli) with a width of 2 meters and 29,250 vertical wind turbines placed under the chassis. Using RETScreen software, the capacity of the resulting system is estimated at 39.9 GW/year. The system would lead to a reduction in CO₂ and GHG emissions of approximately 28,211 tCO₂/year. The payback period of this project is estimated at 9 years with a lifetime of 25 years.</span>