City Gas Research Articles

Impact of city gas on mortality in China: National and regional estimates

Developing the natural gas industry is considered an effective way to reduce pollution and improve human health. To verify whether the expansion of city gas consumption can effectively decrease mortality rate in China, this study assesses the impact of three different types of city gas on mortality by employing panel data from 30 provinces in China during the period of 2001–2018. Furthermore, the regional difference in the influences of gas consumption on mortality rate is analyzed from the perspective of economic development, spatial distribution, and development of the natural gas industry. The empirical results indicate that the expansion of city gas decreases Chinese mortality rate effectively. Analysis of the impact of different types of gas consumption reveals that a 1% increase in coal gas supply results in boosting mortality by 0.008%. Meanwhile, LPG and natural gas are employed to inhibit mortality. Based on the heterogeneity analysis, the impact of city gas supply on mortality has a scale effect. Finally, policy implications are highlighted for the Chinese government with respect to accelerating the development of the natural gas industry and promoting the building of a healthy China.

Risk analysis and mitigation for the city gas distribution projects

Purpose This study aims to identify the operational and financial risks associated with the city gas distribution project in India and suggest appropriate strategies to mitigate them. Design/methodology/approach This study aims to identify the operational and financial risks associated with the city gas distribution project in India and suggest appropriate strategies to mitigate them. The survey data is evaluated using factor analysis to understand the latent structure of the critical risk factors. Second, the author uses Situation, Actor and Process–Learning, Action and Performance framework to suggest the mitigation strategies for the identified operational and financial risk factors. Findings The research identified five critical risk factors and suggested 39 mitigation strategies to address operational and risk factors impacting CGD projects. The findings of this research will enable the CGD companies to formulate long-term strategies for their business and adopt proactive measures to mitigate the operational and financial risks causing delay and increasing project costs. This study also highlights the importance of government support in developing a conducive environment for CGD industry to thrive. Originality/value The CGD projects are critical for natural gas growth in India’s energy mix. The project delay leads to a rise in the total cost involved and increases the payback period for the CGD companies. To the best of authors’ knowledge, this research is first of its kind that identifies the critical operational and financial risks affecting CGD projects in India and suggests the mitigating strategies for them.

City gas distribution projects delay in India: a critical assessment of risks

PurposeThis study aims to identify and rank the operational and financial risks causing a delay in the commencement of the city gas distribution project in India.Design/methodology/approachThis study reviews the literature to identify operational and financial risks variables associated with infrastructure projects. Followed by a survey to isolate and assess the critical risk factors for city gas distribution network project in India. The survey data is evaluated using factor analysis to understand the latent structure of the critical risk factors. Second, the author ranks the identified variables as per significance by using the mean score method.FindingsFive critical risk factors with 20 variables were extracted and assessed to build more understanding of their significance and impact on city gas distribution network project.Originality/valueThis study is the first attempt to follow the management approach to identify and rank operational and financial risks impacting city gas distribution project.

Deceleration of the development of city gas connections amidst the covid-19 pandemic in the metropolitan area

The National Energy Policy captured the basis for renewable energy development in Indonesia and also specified a national target for the optimal energy mix. For these fundamental reasons, several unprecedented strategies, blueprints, and collaborations are to be explored in the long term. Apparently, one of the key objectives was to exploit natural gas as the primary and eco-friendly energy resource. This profitable gas was projected to significantly contribute a minimum of 22% of total energy toward enhancing economic growth. Approximately, 10 million city gas connections are required by 2025, in order to achieve the set goals. However, a gap exists between the initially planned city gas connections to the distribution network, and the realization during the Covid-19 pandemic in 2020. This global phenomenon poses a challenge to virtually all economic segments, including energy, as the demand plummeted drastically. Based on Indonesia’s National Energy Policy, the first proposed target was to develop 266,070 gas connections. The project was subsequently adjusted to 127,864. Surprisingly, the realization surpassed the new arrangement by over 6% or was about 135,286. However, the figures obviously comprehended 50.84% of the projects were stalled, contrary to the vision of constructing a minimum of 10 million city gas pipe connections in 2025. This study provided a profound description of the impact of the reduction in abovementioned development on the expected outcome, using the multivariable regression method. The results revealed 96.92% of data from the applied variables were able to describe the developed linear model.

Exergy Analysis and Economical Study on Using Twisted Tape Inserts in CGS Gas Heaters

This experimental assessment aims to study the impact of twisted tape insert on city gas station (CGS) heaters performance. The interesting point in this study is that the unflavored pressure drop in many cases of using tube inserts is quite favor in this case. In other words, this insert is used in a station whose primary duty is to heat the natural gas and reduce its pressure, and the insert does a part of the pressure reduction besides enhances the heat transfer rate. The effects of twist ratio and heater water temperature on the heater performance features are assessed, and the outcomes are compared with those without inserts case. The outcomes indicated that the use of insert entails an intensification in the heater performance by up to 16% and the best heat transfer enhancement belonged to the insert with the twist ratio of 1.05 at the heater water temperature of 35 °C. In addition, the economic analysis revealed that the capital return rate and the time of the return of capital are quite desirable. Furthermore, the exergy analysis showed that the destroyed exergy diminishes by using the twisted tape insert, and the higher the twist ratio and heater water temperature, the less the destroyed exergy. This is because a CGS unit duty is reducing pressure, and using an insert can be helpful.

Challenges and prospects of developing city gas to reduce imported LPG in Indonesia

Indonesia has natural gas potential that can be developed through the city gas program. Although the city gas program has been designed since 2009, its effectiveness in addressing the critical LPG issues is still insignificant. The achievement of the city gas development target in 2019 has only reached 12% of the government’s target of 4.7 million SR (house connections) in 2025. We conducted content analysis and in-depth studies on several legal products and literature related to opportunities and challenges in the city gas development. We found that the main problem was the limited investment from both the government budget and the corporate budget. Challenges of city gas development are low project economics, delays in upstream natural gas projects and natural gas infrastructure development, and low customer satisfaction. Meanwhile, obstacles to city gas development are the length of the licensing process, social problems, unclear KPBU (Community - Business Entity Cooperation) scheme, and undefined handling of LPG subsidy (3 Kg). This finding is expected to be taken into consideration in the formulation of a more effective and massive city gas development strategy in the future.

Which Pathways Should Indonesia Follow to Achieve Its Energy Development Goals into the Future?

Indonesia has developed a plan for its energy sector far into the future, however, the plan might be challenged by several international agreements that the country ratifies. The UN Report suggests several pathways for Indonesia to achieve the SDGs’ goal number 7 (affordable and clean energy). It challenges the current plan for expanding city gas networks, instead, it offers extensive uses of the electric cooking stove. It recommends that Indonesia accelerates its energy conservation efforts and reduce its energy sector’s greenhouse gasses emission by a figure which is higher than the original target. Besides, Indonesia should develop no more new coal-fired power plants and should continue to remove fossil fuel subsidies and encourage the issuance of green financing. This paper supports but also challenges the report by several arguments based on the country’s energy-economy-environment problems.

Performance Assessment of Japanese Electricity and Gas Companies during 2002–2018: Three DEA Approaches

This study has compared Japan’s major electricity and gas companies in terms of their corporate performance measures from 2002 to 2018 using three types of Data Envelopment Analysis (DEA) approaches. We develop a new type of efficiency measures and indexes for DEA and then compare the performance of major electric power companies and city gas companies by examining a recent data set that include years after the Fukushima Daiichi Nuclear Power Plant accident. The data set incorporates the number of patents as an output that represents companies’ capability for technology innovation to investigate intertemporal changes of efficiency through index measures. The results provide us with two important findings. First, the electricity industry has experienced long-term difficulty due to the nuclear plant disaster; while the gas industry experienced less difficulty from the accident. Second, both industries have been gradually improving performance measures in recent years. However, the gas industry has outperformed the electricity industry. From the results, this study discusses important policy implications for Japan’s energy utility industry and academic research on the industry.

Optimized dispatching of city-scale integrated energy system considering the flexibilities of city gas gate station and line packing

Integrated Energy System (IES) has been proved to be able to effectively improve energy utilization and economic benefits. In the day-ahead dispatch of city-scale IES, electricity-gas interconnection is widely used to realize energy complementarity among regions, where the pressure regulation and electricity-heat-gas coupling in the gas gate station powered by Combined Heating and Power (CHP) device are usually excluded. Therefore, with the gas gate station centered, CHP fired energy hub linearization model, the optimized dispatching model of city-scale IES considering the flexibilities of city gas gate station and line packing is established in this paper where an Integrated Electricity and Gas System (IEGS) is running among regional Combined Cooling, Heating and Power (CCHP) systems, applying power and natural gas coupled energy flow algorithm. Results of case studies verify the potential of pipeline storage compared with gas storage tanks up to an 8.391% reduction on overall operation cost, a 14.366% improvement on renewable energy utilization and charging/discharging cycles reaching only 0.197 times of those of tanks, especially in areas with rich renewable energy. Besides, regulated by CHP fired energy hub which is worth constructing for its economic benefits and alleviation of peak power supply pressure, the average pipeline pressure proportional to stored gas volume increases by 5.885%, enhancing the flexibility of line packing. Moreover, this paper demonstrates that heating economy of gas boilers and electric boilers in comparison to gas turbines rises in turn with the increase of Gas-Electricity Price Ratio (GEPR). Lastly, Quasi Elastic Coefficient (QEC) is defined to describe multi-energy consumption sensitivity to Time-Of-Use (TOU) energy tariff, which is helpful in energy pricing and equipment scheduling.

Integration of 3D models of structures and geological composition as an underground infrastructure model

To develop three-dimensional (3D) models as examples of the infrastructure model concept which would be useful for the operation and maintenance or design and construction of underground facilities we integrated 3D models of the geological composition, the structure and the lifeline facilities (water supply and sewerage system, city gas line, electrical power and communication lines) for the underground mall named ESCA in Nagoya City, Japan. In addition to the above 3D models, 3D structural models of tunnels of the underground railway passing underneath ESCA are developed based on as-built drawings in cooperation with the transportation authority of Nagoya City, and settlements occurred by that construction are visualized in 3D models from a record of the construction of tunnels of that subway. ESCA built out a 3D data platform with browser software for daily maintenance and planning of modification work of the underground mall.

Method on Utilization of Low Quality Biogas as a Fuel for 4 Stroke Spark Ignition Engine of Electric Generator

Biogas quality in many installation of anaerobic digester for processing organic waste are found not optimum, especially in developing country where understanding of anaerobic processing is not well known. The methane content in the biogas are usually low that make it not possible to be utilized as a fuel of the engine. Biogas Purification usually will be introduced as a solution. But this idea is about complicated for simple or small anaerobic digester. Other solution is suggested by using enrichment of biogas by using other fuel such as hydrogen or blended with city gas such as LPG gas. But for preparing hydrogen gas or commercial will also costly. This research introduces simple technique for biogas enrichment by using denatured alcohol. The biogas contents were found around 30% vol. methane (CH4) and around 2% Carbon dioxide (CO2). The price of denatured alcohol is relative cheap because the selling tax is not as much as drinking alcohol. Engine with bigger combustion (420 cc) chamber was prepared for this purpose to make possible to be fueled with biogas. The compression was set to reach 10 bar. The clearance of the both intake and exhaust valve was set in order to be possible to be running by using biogas. The biogas-air mixer was design for this purpose. The carburetor was set for use of denatured alcohol. It is found that the engine is running well by using biogas fuel that is enriched by using denatured alcohol. The emission was found better comparing using gasoline for the same engine. The fuel consumption is reported for future economic analyses.

Analysis on the Causes of the third party destruction of City Gas Pipelines and Research on Countermeasures

While the universal application and rapid development of natural gas have improved people’s living standards, it has also improved the traditional energy structure and contributed to environmental protection. However, with the increasing speed and scale of urban gas engineering construction, the safety maintenance and prevention of gas pipelines that follow are particularly important for gas companies. In particular, the third-party construction unit does not pay enough attention to the gas pipeline network, and it is easy to cause damage to the pipeline network during construction and cause gas pipeline leakage accidents. This paper uses big data technology to find the key elements of third-party construction and construction damage risks in massive data, builds a high-prone construction area model and construction damage risk model, provides countermeasures against damage risks, and improves the effectiveness and prevention of external damage risks. Targeted, reduce the frequency and extent of damage to gas pipelines and facilities, and ensure the safe operation of the gas pipeline network.

Method of determining the optimal version of the piezometer of gas distribution networks of medium and high pressure

The article deals with the issues of determining the optimal type of piezometric pressure graph in high-and medium-pressure gas pipelines in the design of gas distribution networks. Along with the most commonly used ways to reduce the cost of building gas distribution networks by finding the optimal configuration of gas pipelines, which give a great economic and environmental effect, it is necessary to rationally use the pressure drop provided to the network. This step in engineering practice allows you to additionally get money savings. The use of various schemes for supplying consumers with gas in cities and villages also has a great economic effect, but modern equipment allows you to make the transition to a single-stage scheme of gas distribution networks for cities. When designing gas distribution networks, the available pressure drop can be used by implementing various technical solutions, but the correct choice of pressures in the nodal points contributes to an economic effect. The designed configuration of the gas distribution network with the adopted type of piezometric graph can ensure reliable operation for a long time. The results obtained are recommended for use in the design of gas distribution networks of cities, other settlements and distribution networks of industrial enterprises

A Case Study Research on Retro Energy Private Limited

It was mid-December 2011; the climate in India was as pleasant as it could be, but the business climate of Indian City Gas Distribution (CGD) sector was not. The recent changes in the Regulatory Policy had further fueled the growing unpredictability of the sector. The thought of the business and market implications of the policy changes made Shravan Ragunathan, Founder Director, Retro Energy Private Limited (REPL) fret, and sweat on otherwise a cold evening. He brought his attention back to the last slide of his presentation for the board meeting to be held the next day, and keyed in the quote of Peter Drucker- “The best way to predict future is to create it”. The board meeting was called to review REPL’s business strategy in the wake of the changed business environment. Shravan was expected to present to the board a new strategy- whether to extend REPL’s techno-commercial consultancy services to the international market or diversify domestically. Headquartered at Ahmedabad, REPL- the techno-commercial oil and gas consulting company had been contemplating a strategy change for quite a while. It had been inconclusively weighing the options available to it- whether to partner with the established consulting giants in India; or venture into the CGD business itself; add new domains to its existing consulting spectrum, or grab the consulting opportunity in Nigeria. But, the nearing deadline for responding to the Nigerian proposal, made immediate decision on REPL’s future strategy a necessity.

SARIMAX 모형을 이용한 발전용 가스 수요 분석 및 예측 연구

In this study, we consider the problem of forecasting daily gas demand for power generation. Natural gas, which is one of the major energy sources of South Korea, is classified into two categories by its usage: city gas and gas for power generation. Natural gas for power generation is used for producing electricity and the amount of its usage keeps increasing. It is very important to accurately forecast the natural gas demand for stable operations of the gas supply system as well as prompt response to request for power generation. In this study, time series analysis models are used for forecasting daily gas demand of power generation, that is, we use SARIMA model (Seasonal ARIMA) model and the SARIMAX model, in which an exogenous variable is additionally considered. In this study, the models were constructed through the process involving several sophisticated phases, such as, stationarity and seasonality tests, order selection, estimating parameters, and diagnostic checking of the models. To evaluate the performance of the proposed model, computational comparison experiments with various existing forecasting methods were conducted. Results of the empirical analysis show that the proposed SARIMAX outperformed benchmark methods in terms of the several accuracy measures.

Development of Residential Fuel Cell "Ene-Farm Mini"

Tokyo Gas Co., Ltd. has launched residential distributed power generation system “ENE-FARM” which is a micro-CHP system in 2009. The number of cumulative sales reached 300,000 in Japan and 130,000 in Tokyo Gas in FY2019. In order to further spread of “ENE-FARM”, the world's smallest residential fuel cell "ENE-FARM mini" manufactured by Kyocera Corporation was released in October 2019.“ENE-FARM mini” has been developed with the concept to minimize the system size, optimize the rated power of the system with ensuring the power generation efficiency, add the function of continuous power generation during blackout, utilize the IoT technologies, and reduce the cost for installation work.To minimize the system size, the SOFC system integrated of the cell stack and the reformer was adopted. The cell stack’s size was reduced by lowering the rated power to 400 W. The lowered power is also suitable to the recent energy demand decreasing by the spread of energy saving house. The system was introduced to minimize the size of the hot water tank to 20 L, much smaller compared to the conventional “ENE-FARM”. As a result, the size of the whole system is minimized to the point of the smallest in the world, as small as the size of the air conditioner outdoor unit. It is expected to meet more demands from the customers who were not able to afford the large space for the installation due to the limited space available in their residences.In order to lower the rated power to 400 W power with securing the power generation efficiency, it is challenge to secure the heat required for power generation. Hot Box covering the cell stack was designed to achieve high thermal insulation by reducing the heat dissipation loss. As a result, the high power generation efficiency of 47% (LHV) was achieved due to maintain high-temperature conditions.Moreover, the function of continuous power generation during blackout was introduced to “ENE-FARM mini”. Although the blackout occurs during power generation, it is capable to supply the power to the emergency outlet and the boiler, as long as the city gas lines are operating. Therefore, it is possible for users to operate some of the household appliances through the emergency outlet. The hot water supply system and the floor heating system can be functional if the water lines are operating.“ENE-FARM mini” was compatible with the IoT system. Many features such as the usage amount of gas, electricity, water and utility costs can be easily checked on the user’s smartphones. The users also can remotely control many systems such as the hot bath and the floor heating system. Additionally, the usability was improved by implementing the smart speaker compatibility.It is the critical challenge to reduce the cost for installation work. The minimized and weight saved system made it possible to carry the whole assembly with a subcompact car. It only requires two persons to carry and install the system even in a narrow space with a depth of 500 mm. Because the center of gravity point was set to be lower, the base components could be compact and lightweight. The typical weight of the base components was about 27 kg which consists of two components of 13.5 kg. Therefore, the base components can be carried by only one person. It leads to simplify the installation work and reduce the cost for installation.We will continue to contribute to the comfortable living of customers, the preservation of the global environment, and the enhancement of resilience through the spread of "ENE-FARM". Figure 1

Hydrogen penetration and fuel cell vehicle deployment in the carbon constrained future energy system

This research details outcomes from a global model which estimates future hydrogen penetration into a carbon constrained energy system to the year 2050. Focusing on minimum and maximum penetration scenarios, an investigation of global fuel cell vehicle (FCV) deployment is undertaken, cognizant of optimal economic deployment at the global level and stakeholder preferences in a case study of Japan. The model is mathematically formulated as a very large-scale linear optimization problem, aiming to minimize system costs, including generation type, fuel costs, conversion costs, and carbon reduction costs, subject to the constraint of carbon dioxide reductions for each nation. Results show that between approximately 0.8% and 2% of global energy consumption needs can be met by hydrogen out to the year 2050, with city gas and transport emerging as significant use cases. Passenger FCVs and hydrogen buses account for almost all of the hydrogen-based transportation sector, leading to a global deployment of approximately 120 million FCVs by 2050. Hydrogen production is reliant on fossil fuels, and OECD nations are net importers - especially Japan with a 100% import case. To underpin hydrogen production from fossil fuels, carbon capture and storage (CCS) is required in significant quantities when anticipating a large fleet of FCVs. Stakeholder engagement suggests optimism toward FCV deployment while policy issues identified include necessity for large-scale future energy system investment and rapid technical and economic feasibility progress for renewable energy technologies and electrolyzers.

日本国内でのメタネーションの可能性：電力・都市ガス需給モデルによるCO2回収・水電気分解・サバティエ反応システムの技術経済的評価

日本国内でのメタネーションの可能性：電力・都市ガス需給モデルによるCO2回収・水電気分解・サバティエ反応システムの技術経済的評価

GIS-Enabled Digital Twin System for Sustainable Evaluation of Carbon Emissions: A Case Study of Jeonju City, South Korea

Despite the growing interest in digital twins (DTs) in geospatial technology, the scientific literature is still at the early stage, and concepts of DTs vary. In common perspectives, the primary goals of DTs are to reduce the uncertainty of the physical systems in real-world projects to reduce cost. Thus, this study is aimed at developing a structural schematic of a geographic information system (GIS)-enabled DT system and exploring geospatial technologies that can aid in deploying a DT system for a real-world project—in particular, for the sustainable evaluation of carbon emissions. The schematic includes three major phases: (1) data collection and visualization, (2) analytics, and (3) deployment. Three steps are designed to propose an optimal strategy to reduce carbon emissions in an urban area. In the analytics phase, mapping, machine learning algorithms, and spatial statistics are applied, mapping an ideal counterpart to physical assets. Furthermore, not only are GIS maps able to analyze geographic data that represent the counterparts of physical assets but can also display and analyze spatial relationships between physical assets. In the first step of the analytics phase, a GIS map spatially represented the most vulnerable area based on the values of carbon emissions computed according to the Intergovernmental Panel on Climate Change (IPCC) guidelines. Next, the radial basis function (RBF) kernel algorithm, a machine learning technique, was used to forecast spatial trends of carbon emissions. A backpropagation neural network (BPNN) was used to quantitatively determine which factor was the most influential among the four data sources: electricity, city gas, household waste, and vehicle. Then, a hot spot analysis was used to assess where high values of carbon emissions clustered in the study area. This study on the development of DTs contributes the following. First, with DTs, sustainable urban management systems will be improved and new insights developed more publicly. Ultimately, such improvements can reduce the failures of projects associated with urban planning and management. Second, the structural schematic proposed here is a data-driven approach; consequently, its outputs are more reliable and feasible. Ultimately, innovative approaches become available and services are transformed. Consequently, urban planners or policy makers can apply the system to scenario-based approaches.

Analysis on Installation Technology and Construction Management of City Gas Pipeline

Analysis on Installation Technology and Construction Management of City Gas Pipeline