Self-sufficiency Ratio Research Articles

The emergy analysis of southern China agro-ecosystem and its relation with its regional sustainable development

The agricultural economy of Fujian Province has grown rapidly since the 21st century. In order to evaluate the impact of economic growth on the sustainability of agro-ecosystems, emergy analysis was used to study the dynamics of agro-ecosystem and its sustainable development capacity in Fujian Province from 2000 to 2016. The results showed that the total emergy input and output of agro-ecosystem in Fujian Province presented an upward trend from 2000 to 2016. Environmental loading ratio (ELR), emergy investment ratio (EIR) and per capita emergy used (EUPP) all showed a growth trend. The ELR and EIR are significantly positively correlated with GDP per capita. Emergy self-sufficiency ratio (EYR), emergy dollar ratio (EDR), emergy sustainability index (ESI) and emergy index for sustainable development (EISD) showed a downward trend from 2000 to 2016. The results suggested that agro-ecosystem of Fujian Province is a sustainable development system, but the sustainability of system is low and gradually declining. In the future, the sustainable development of agro-ecosystem in Fujian Province can be promoted by replacing traditional fertilizers with organic fertilizers, using clean energy to generate electricity, developing ecological agriculture, increasing investment in science and technology, and controlling population growth.

The forecasting of fish production, imports and exportswith the analysis of domestic consumption and expected self-sufficiency ratio during the period 2017-2030 in Saudi Arabia. Application of VARX model

The main purpose of this research is to use augmented vector autoregressive model to forecast the production of fish, imports and exports in order to compute the expected domestic consumption and analyze the self-sufficiency ratio that expected to occur during period (2017-2030). According to (IC) the appropriate empirical model of these group was VARX(2) model with constant and quadratic trend. From the results of conditional lest squares estimates, the statistical tests proved that the linear trend terms as well quadratic improved the predictive ability of the model. Also the quantity of both production, imports and exports lagged one and two period has significant effect, and their addition improves the predictive ability of the model. The prices of both imports and exports in their logarithmic form have a significant effect and improvement predictive ability of the model.From results of prediction, quantity consumption as well self – sufficiency ratio was computed, and the results showed that self-sufficiency ratio will decrease with 2.4% annual growth rate. The market gap will be positive and tend to narrow. the research recommended that the interest in establishing of the specialized training institutes, Supplying the incentives that encourage young people to fish, improving the factors of fish production and supplying the local production of fish at appropriate prices to consumers.

Measuring Energy Efficiency and Environmental Performance: A Case of South Asia

When assessing energy efficiency, most studies have frequently ignored environmental aspects even though the concept has been widely used in the past. This study evaluates the energy efficiency and environmental performance of South Asia by using DEA (data envelopment analysis) like mathematical composite indicator. We construct a comprehensive set of indicators, including an energy self-sufficiency ratio, energy production over consumption ratio, energy imports, diversification index of energy imports, energy reserve ratio, GDP productivity, energy intensity, per capita energy consumption index, carbon emission index, carbon emission index per unit of energy consumption and share of renewable energy in order to develop an energy efficiency and environmental performance index. Unlike other studies, this study first examines each indicator and then estimates a combined score for each country. The results reveal that Bhutan as a more secure country and Pakistan showed a decreasing trend, while Sri Lanka and India performed satisfactorily. Remarkably, Bangladesh, Nepal and Afghanistan showed a decreasing trend. This study proposes a policy that increases the cross-border trade of renewable energy for long term energy efficiency and environmental performance.

An economic study for the production of sugar beet in Menia Governorate

The research aims to study the current production situation of sugar beet crop in Menia Governorate, Egypt during the period (2001-2017) and to identify the most important factors that affect the quantity of production and analysis of production efficiency, and studying some of the standards of economic efficiency of sugar beet crop in the study sample in Menia Governorate. Sugar production of sugar cane and sugar beet was about 1026.1, 718.5 thousand tons respectively. The self-sufficiency rate of sugar reached 66.1% as an average for the period (2001-2017). The self-sufficiency ratio a generally growing statistically significant trend. While the area cultivated with beet is a growing statistically significant trend in Egypt and Menia governorate. The result showed that the most net return per acre of sugar beet crop was in Mallawy it reached approximately 9819.1 pounds / acre. While in Abou-korkas and the total sample it reached approximately 7281.9 – 8445.6 pounds / acre respectively. The study indicated that the most important problem that faces the producer of sugar beet crop in Menia was increasing in the variable costs; it estimated 14% of producer opinions.

Potential for exploiting the synergies between buildings through DSM approaches. Case study: La Graciosa Island

Many studies have demonstrated the potential of large scale energy analyses when it comes to achieving highly energy-efficient districts. Much emphasis has been placed on giving insights into how to obtain accurate energy demand and solar potential estimations for whole regions, as a means of enhancing the integration of renewable energies, achieving higher self-sufficiencies or decreasing the energy costs. However, it is necessary to figure out whether it would be possible to enhance the economic savings and integration of renewable energies even more. This could be done by considering on a district scale the synergies between buildings, DSM strategies and electricity storage at building level.Using as a case study a microgrid in a district located in La Graciosa Island (Spain), this work proposes a novel strategy that encourages sharing surplus electricity between different prosumers, in order to maximize the overall cost savings and the utilization of renewable energy in the district. In this case, the prosumers are equipped with thermostatically controlled loads (heat pumps) and renewable generation with electricity storage (PV modules). In addition, a comparison between different preconditioning strategies is carried out, determining the optimal strategies during a whole year and reaching important conclusions. The influence of considering different time horizons for the optimization of these preconditioning strategies is also examined. Last of all, a sensitivity analysis regarding the main design parameters is performed.The results prove that, by promoting energy sharing, the proposed concept is capable of raising the self-consumption and self-sufficiency ratios of a district (reaching 42% and 64% respectively) as well as the cost savings. The results are very dependent on the considered feed-in-tariff: the lower it is, the more profitable it is to implement the proposed concept. The present study also shows the benefits that can be obtained from DSM approaches on a district scale: different precooling strategies, which may be implemented without additional investments, were chosen instead of the normal schedule on around 66% of the summer days. Altogether, the proposed approaches may effectively contribute to resource conservation at large scales.

Service Effectiveness of the Nature Centers for Sustainability of Environmental Education and Forest Policy Implications

The purpose of this study was to explore the relationship between service effectiveness of the Nature Centers of Forest Bauru of Executive Yuan in Taiwan (Nature Centers) and sustainability of environmental education and forest policy implications. The (n = 1520) participants were selected through purposive and quota sampling, and the questionnaires were divided into four categories: Potential target customer groups, potential operators, the public, and website users from 1 July to 31 August 2017. Canonical correlation analyses were used to explore the relationship between two variables. The study results revealed the significant relationships between service effectiveness and forest policy implications, and two canonical factors were extracted. The first pair of canonical correlation analyses reveals that higher overall service effectiveness is more likely to catch the attentions of participants with the overall forest policy implications. The second canonical correlation analysis suggests that forest policy implications factors of protected coast forest, exotic species, green economy, forest resource management, and wood self-sufficiency ratio were positively associated with service effectiveness for natural resources and negatively associated with those of teaching quality. The implication for further research and practical applications in terms of cultural and creative research is suggested.

Phosphorus Demand for Food Security: A Case Study of a Food-Deficient Country

The modern global food production system relies heavily on a considerable input of phosphorus. Sustainable food and agriculture need integrated phosphorus management, especially in phosphorus-scarce and food-deficient countries. This study aimed to investigate the phosphorus requirements to meet the future food demand for a phosphorus-scarce and food-deficient country, Comoros, as a case study. With its rapid population growth, domestic food production is far from meeting the food demand in Comoros, and the country relies on imported foods to satisfy the national needs; it is currently a net food importer, an import-dependent nation. We first calculated the virtual and embedded phosphorus flows through food trade in Comoros, from 1991 to 2013, and then estimated the phosphorus requirements for the future food demand under two scenarios. We found that the total virtual and embedded phosphorus through imported food increased from 163,313 to 493,190.97 kg and 53,190.12 to 143,009.62 kg in 1991 and 2013, respectively. Whereas, the embedded phosphorus through exported food shifted from 2548.75 to 1334.5 kg in 1991 and 2013, respectively. In addition, the Self-Sufficiency Ratio (SSR) analysis found that Comoros’s SSR is far below 100%; it varied from 46.27% in 1991 to 29.70% in 2013, indicating that the capacity of domestic production to cover domestic consumption fell by 16.57% during that period. In terms of phosphorus requirements, Comoros will require approximately 3,003,435.09 kg of phosphorus to reach 90% of the SSR or 3,337,150.10 kg to achieve 100% of the SSR, by 2030. These amounts could allow farmers to domestically produce the entire volume of food crops and livestock products that would otherwise be imported from trade.

Aggregation effects for microgrid communities at varying sizes and prosumer-consumer ratios

Self-consumption is an increasingly economically attractive solution for electricity generated by distributed energy resources, which also reduces transmission losses, power line overload and grid instability. Yet, at single-building scale, production and demand do often not coincide. Microgrids are proposed as a means to trade surplus energy produced with local prosumers and consumers, to take advantage of complementary load profiles. Here we define a consumer as a single metered residential unit, a prosumer as a consumer with a photovoltaic system, which first uses the on-site energy generated prior to exporting the surplus, and the microgrid as a clearly defined number of both prosumers and consumers. In this article, we systematically analyze to what extent varying microgrid sizes and prosumer-consumer ratios affect local self-consumption and self-sufficiency rates. To that end, we developed a simulation model that uses real-world load profiles from 4190 residential buildings as input data. We find that the prosumer-to-consumer ratio is more important than the absolute microgrid size, for microgrids sizes greater than ten. The results also indicate that prosumer-to-consumer ratios in the range of 40%-60% have the best performance. Each simulation is also compared to the baseline scenario of a stand-alone prosumer, which shows significantly better self-consumption ratios and self-sufficiency ratios for microgrids due to aggregation effects. Finally, this work may also be used as a reference to design residential microgrid communities for various prosumer-consumer compositions and various production-to-demand ratios.

Analysis of Rooftop Photovoltaics Diffusion in Energy Community Buildings by a Novel GIS- and Agent-Based Modeling Co-Simulation Platform

The present work introduces an empirically ground agent-based modeling (ABM) framework to assess the spatial and temporal diffusion of rooftop photovoltaic (PV) systems on existing buildings of a city district. The overall ABM framework takes into account social, technical, environmental, and economic aspects to evaluate the diffusion of PV technology in the urban context. A city district that includes 18 720 households distributed over 1 290 building blocks and a surface area of 2.47 km2 is used to test the proposed ABM framework. Results show how the underlying regulatory framework (i.e., the rules of the internal electricity market) influences the pattern and intensity of adoption, thus realizing different shares of the available potential. Policies that support the establishment of `prosumers' within Condominiums (i.e., energy community buildings), and not in single-family houses only, is key to yield high diffusion rates. The installed capacity increases by 80% by switching from the one-to-one configuration to the one-to-many paradigm, i.e., from 5.90 MW of rooftop PV installed on single-family households and/or single PV owners to 10.64 MW in energy community buildings. Moreover, the possibility to spread the auto-generated solar electricity over the load profile of the entire population of Condominium results in self-consumption rates greater than 50% and self-sufficiency ratios above 20% for the majority of the simulated buildings.

Daya saing produk unggulan sektor pertanian Indonesia dalam hubungannya dengan pertumbuhan Ekonomi

This study aims to identify and analyze the competitiveness of Indonesian products in the agricultural sector, especially rice, oil palm, vegetables, fruits and livestock products, also the relation between economic growth and some commonly used competitiveness indicators. The approach used is RCA (Revealed Comparative Advantage), RSCA (Revealed Symetrics Comparative Advantage), Self Sufficiency Ratio (SSR), Import Dependency Ratio (IDR). The results of the study are as follows: The export performance of Indonesian agricultural products in general relatively weak. Almost all agricultural commodities have low competitiveness, except for plantation sub-sector products, especially rubber and palm oil which have high competitiveness, the remaining products such as horticulture, food crops, livestock products, and competitiveness of horticulture relatively low in the international commodity market. In this study, also found in general, the relation between the rate of economic growth and some magnitudes of international trade performance does not show a significant relationship for food crops, horticulture, plantations, and livestock products. Indonesia is approaching the stage of self-sufficiency, especially for food crops, but for other agricultural sector commodities, it is still very dependent on imports to meet domestic consumption needs.

Vegetable market: competitive advantages of Georgian product and competition challenges

The paper evaluates the level of competition on the vegetable market. Based on the analysis of the production development trends and resource potential, dynamics and ratio of export and import of agricultural products, including vegetables are presented; dynamics of self-sufficiency ratio of these products is studied; challenges of food security and competitive advantages of Georgian vegetables are identified.The article concludes that the country has a significant potential for exporting vegetables both to the countries of Europe and Middle East. The paper discusses the factors that hinder export of vegetables; in addition, the ways for reducing dependency on seasonality, opportunities for the development of modern greenhouses and mechanisms for supplying goods to customers all year round are suggested.On the basis of analyzing the level of competition on the vegetable market, vegetable business is considered as monopolistic. In addition, it is calculated that, currently, local vegetables products account for only 75% of the market.The paper evaluates the outcomes of high market power caused by monopoly in vegetable business; the impact of market power on pricing mechanism and the welfare of population is determined. In accordance with the problems identified, conclusions are made and recommendations for solving these problems are suggested.

Emergy analysis, water-heat utilization, and carbon emission of typical cropping patterns in the oasis irrigation area.

Reasonable cropping pattern can improve resource utilization efficiency, reduce environmental risks in agricultural production, and achieve the goal of resource saving coupled with high production and efficiency. We evaluated the production effects of typical cropping patterns in an arid irrigation region from several aspects, including resource utilization, carbon emissions, economic benefit, emergy self-sufficiency ratio and net emergy yield ratio, with the method of emergy theory, to provide theoretical and practical basis for the establishment of efficient cropping with lower resource investment and carbon emissions but higher yield and resource utilization efficiency combined with the sustainability of agricultural production. The results showed that, high-efficient wheat-maize intercropping production pattern (integration of no tillage with 25 to 30 cm height of wheat straw covering in the wheat strip and two-year plastic mulching in the maize strip, NTSI) had the best performance in grain yield boosting, with the yields 13.5% to 16.9% and 13.8% to 17.1% higher than that in local traditional production patterns (i.e., wheat-maize intercropping, CTI, and monoculture maize, CTM), respectively. Moreover, NTSI increased water use efficiency and solar energy use efficiency by 12.4% to 17.2% and 6.1% to 8.1%, compared to CTI, respectively. Compared to CTI and CTM, NTSI improved the effect on carbon emission reduction by decreasing total soil CO2 emission by 618 to 895 kg·hm-2 and 1804 to 2002 kg·hm-2 with the ratio of 12.1% to 16.4% and 28.6% to 31.0%, but increased carbon emission efficiency by 29.3% to 40.1% and 58.9 to 71.4%, respectively. Meanwhile, the NTSI pattern had obvious resources saving potential. Compared with CTI and CTM, NTSI reduced total input by 1424 to 1431 yuan·hm-2 and 501 to 1547 yuan·hm-2, with the proportional reduction being 12.6% to 13.6% and 4.9% to 14.6%; however, increased total output by 4309 to 4603 yuan·hm-2 and 8439 to 11057 yuan·hm-2, the increased ratio was 11.2% to 11.8% and 24.4% to 36.3%; also, increased net return by 5740 to 6027 yuan·hm-2 and 9544 to 11558 yuan·hm-2, and the improved percentage was 19.6% to 22.4% and 40.1% to 57.7%, respectively. Therefore, the high-efficient NTSI pattern had greater input-output ratio by 27.9% to 29.0% and 40.5% to 45.6% than CTI and CTM, respectively, similarly, greater benefit per cubic meter of water by 19.9% to 23.2% and 27.7% to 39.3%, respectively. The emergy self-sufficiency ratio of NTSI pattern was 57.2%, being 4.0% and 12.2% higher than CTI and CTM, respectively. NTSI pattern's net emergy yield ratio was 0.173, being 10.0% greater than CTI but 11.7% lower than CTM. With respect to resource utilization, carbon emission reduction, economic benefits and the sustainable development of high-efficient intercropping pattern, the integration of no tillage with straw covering and two-year plastic film mulching measures had higher economic activity, better function of agricultural system, greater production efficiency, and higher returns on energy value. We concluded that NTSI could be a high-efficiency farming system pattern on resources saving, carbon emission reduction, high yield and efficiency in arid oasis irrigation areas.

THE IMPACT OF BIOFUELS PRODUCTION IN THE WORLD ON THE PRICES OF EGYPTIAN IMPORTS OF FOOD COMMODITIES

Vthe natural sources of energy such as oil, coal and all other fossil fuels, bio fuels is defined as an energy that derived from living organisms, whether plant or animal, the production of bio fuels is consumed with about , and about 9% of the quantity produced of the oils to produce biodiesel, which will rise to 20% by 2018. And that 2% of the total area of crops in the world, used in the production of bio fuels will rise to 4% by 2030. The study problem can be summarized of the rise in petroleum prices from $49 a barrel in 2000 to 146 dollars in 2015, and are the major countries trying to extend its influence on the Middle East states that producing petroleum during internal conflicts of these States, as well as to the orientation of the major countries to produce bio-fuel from plant oils, which leads to a lack of world supply, which had a negative impact on the imported states of the plant oil crops in raising the prices of plant oil crops. The study aims to identify the impact of bio fuels production in the world on import prices of Egypt from strategic food commodities from plant oil . As for the development of self-sufficiency ratio of plant oil it decline significant statistically of about 10.04% of the average period of about 45.8% as the local global, price and the import price for plant oils they are an increase significant statistically by about 4.1%, 5.8% and 9.5% respectively of the average study period of about 553, 910, 1658 dollar/ton. Study of the impact of the world price of a barrel of oil, the net amount of the global biodiesel produced the total elasticity to the function reached about 1.56, that is, an increase of the world price of a barrel of oil, 10% would lead to an increase in the biodiesel production with 15.6% . The study showed that the quantity world biodiesel plant oil, of the most important factors affecting the Egypt important prices the total elasticity reached about 0.25, that is, an increase in the net amount of biodiesel produced by 10%, will lead to an increase in the world price of plant oil by 2.5% during the study period . Studying the impact of the quantity of world production of biodiesel on the import price of plant oils, the total elasticity of function reached about 0.41, that is, an increase in the quantity of world production of biodiesel with 10%, will lead to an increase in the import price of plant oils by 4.10% during the study period. The study showed that the most important factors affecting imports of plant oils in Egypt with increasing the quantity of domestic consumption by 10%, will lead to an increase in the quantity of Egypt's imports of plant oils with about 7.9%, and an increase in the quantity of world production of biodiesel, will lead to increase Egypt's imports of oils with about 5%RECOMMENDATIONS: The study recommends with 1.It is necessary of the ministry of Agriculture to concentrate in its policy on raising the rate of self-sufficiency of plant oil crops. 2. It is must be working diversifying the sources of import markets, plant oil crop from throw studying the world markets or support the farmers to cultivating the oil crops 3. Studying the increasing of the domestic price per ton of oil crops to encourage the farmers to grow these crops to force the world increasing in prices. 4. Studding the possibility of cultivation the oil palm that could contribute to achieving the rate of self-sufficiency of the plant oil for Egypt. 5. Activation the application of the contract farming system for oil crops through cooperatives or agricultural development bank so as to ensure the farmers from marketing his crop.

Self-sufficiency ratio: an insufficient metric for domestic PV-battery systems?

By installing a home battery to accompany rooftop solar PV, grid electricity usage is reduced and self-sufficiency increased. One motivation for pursuing this goal is environmental concern. By modelling domestic PV-battery systems in this work, self-sufficiency is found not to correlate well with CO2 emissions savings, in some cases even correlating negatively. A system’s complexities, such as transmission and distribution losses, are not encapsulated in self-sufficiency. Self-sufficiency should not be considered in isolation when designing PV-battery systems to maximize CO2 emissions savings.

An Analysis of the Water-Energy-Food-Land Requirements and CO2 Emissions for Food Security of Rice in Japan

The aim of this study is to assess the impact of rice-based food security on water, energy, land, and CO2 emissions from a holistic point of view using the Nexus approach, which analyzes tradeoffs between water, energy, and food management. In Japan, both rice consumption and the area harvested for rice have decreased. Maintaining a high self-sufficiency ratio (SSR) in rice production is an important aspect of food security in Japan, impacting the management of key resources, such as water, energy, and land. This study has, therefore, assessed the impact of various SSRs on rice production, focusing on consumption and land-use trends. First, the rice production SSR is predicted to drop to 87% by 2025 within the logarithmic trend of rice consumption and the polynomial trend line of the harvested area of rice. This reflects the fact that rice production is expected to decline more steeply than consumption between 2016 and 2025. Second, this study sets the SSRs for rice in 2025 between 80% and 100%, reflecting a range of low-to-high food security levels. In comparison with the 2016 baseline, about 0.70 × 10 6 additional tons of rice will be produced. Achieving a rice production SSR of 100% will require 10,195 × 10 6 m3 more of water and 23.31 × 10 6 GJ more of energy. Furthermore, an additional 283,000 tons of CO2 will be emitted in 2025, as more energy is used. By contrast, an 80% rice production SSR scenario would save 1482 × 10 6 m3 of water and 3.39 × 10 6 GJ of energy, as well as making a 398,000-ton reduction in CO2 emissions in 2015. A lower SSR would have a positive impact on resource management but a negative impact on food security. It would also reduce the income and economic status of farmers. It is, therefore, important to consider the tradeoffs between food security and resource savings in order to achieve sustainable water, energy, food, and land management in Japan.

Mitigating energy poverty: Potential contributions of combining PV and building thermal mass storage in low-income households

The issue of energy poverty has devastating implications for the society, and it has been aggravated in the past years due to the economic crisis and the increase of energy prices. Among the most affected are those with low incomes and living in inefficient buildings. Unfortunately, the bitter reality is that sometimes this part of the population are facing the next question: Heating, or eating? The declining prices of distributed energy technologies such as photovoltaics provides an opportunity for positive social change. Although their use does not address energy poverty directly, substantial contributions may be made.Measurements of indoor temperatures in a social housing district of southern Spain in 2017 have revealed the unbearable temperatures that the occupants have to endure, both in summer and winter. Using this district as a case study, the present work aims to evaluate the benefits of exploiting its rooftop PV potential to cover part of the electricity consumption of the district (reducing the energy bills), and use the surplus electricity to supply power for the heat pumps in the district. Optimal alternatives regarding maximum PV production, maximum self-sufficiency ratio and minimum investment costs have been found, considering as well different options when sharing the available electricity surplus to improve the thermal comfort of the occupants. As far as the authors know, no previous study has followed an approach aimed at energy poverty alleviation such as the one presented in this work. The results show that using the surplus electricity to heat or cool the whole dwellings would improve the thermal comfort of the occupants in average up to 11% in winter and 26% in summer. If all the PV generation was used or more buildings in the area were employed to install PV modules, improvements up to 33% in winter and 67% in summer could be obtained, reducing at the same time the thermal comfort differences among the dwellings of the district.

Feasible Energy System with Electrochemical Hydrogen Energy Storage for Leveling the Received Electricity at Large-Scale Solar Cell Installation

Introduction Recently, the large-scale installation of renewable energy is required to prevent global warming problem. Especially, the production cost of solar cell has drastically decreased recently. To install large-scale unstable power sources on renewable energy, the management of the gap between electricity demand and supply is a key issue. Thus, large-scale energy storage technologies have to progress to compensate the gap. As an energy storage, chemical energy of hydrogen is a promising candidate. Particularly in urban area, both “global hydrogen” and “local hydrogen” are required to supply sufficient energy to their huge energy demand. “Global hydrogen” is produced from low-cost primary energy globally and is transported for demand with a certain cost. “Local hydrogen” is produced by distributed energy system and is directly supplied without transportation. In the paper, we proposed a cost-competitive distributed energy system with the “local hydrogen” energy storage system. We analyzed the variation of total system cost by installing electrolysis cell (EC), fuel cell (FC) and secondary battery to compensate the gap due to electricity supply from large-scale solar cells (SC). We also proposed the appropriate SC arrangement for a middle size of distributed energy system. Method We evaluated the total system cost on the basis of real data from smart energy control system “Ene-Swallow”, developed by our research group, which manages the megawatt-scale distributed power sources in Tokyo Institute of Technology, Tokyo. The system has 1400 kW-SC, 100 kW-FC, 70 kW-gas engine and 100 kWh-lithium ion battery to manage the 10000 kW-scale electricity demand, which is suitable as a model for a middle-scale society with distributed power sources. The 650 kW-SC, which is almost half of total capacity of SC, is installed on the building (shown in Fig1) located in Tokyo. This building nearly achieves electricity self-sufficiency by the SC, 100 kW-FC and 70kW-gas engine. The building is covered with the “envelope of solar cells” (445 kW at the south wall, 40 kW at the west wall and 165 kW on the roof), where the maximum altitude in winter solstice is 31°. Global solar radiation in summer and winter are 15 MJ/m2 and 8 MJ/m2, respectively. Average temperature in summer and winter are 25°C and 5°C, respectively. In the location, the SCs on the building generates maximum electric power in winter because about 68% of SCs is installed at the south walls. The SC arrangement of the building has much smaller seasonal variation than typical arrangement on the roof to get better matching with the larger energy demands in winter. We constructed the energy system model to analyze the distributed energy system with electrochemical hydrogen energy storage and large-scale SC. In our model, the energy system with SC, alkaline EC, solid oxide FC, compressor, hydrogen tank and battery was assumed. Three hourly data from Apr/1/2016 to Mar/31/2017 were used (power generation from 750 kW-SC on the roofs, 650kW-SC on the building and electricity demand in the area). Based on these data, imaginary set of SC installation was assumed, where total amount of power generation from SC is equivalent to the electricity demand. Fig2 shows the energy flow in the model. In the daytime, the surplus electricity supplied from SC was assumed to be used for the production of hydrogen or battery charge. If the capacity of each device is not sufficient, the surplus electricity was assumed to be curtailed because it is hard to sell it in the future scenario with “large amount of solar energy”. In the night, the electricity to satisfy the demand was assumed to be generated by battery or FC. When the electricity supply is not enough, electricity was assumed to be purchased from an electrical grid. We carried out the energy balance simulation in the model by setting the capacities and technological parameters of devices. Finally, we analyzed the total system cost on the basis of the simulation. The analysis was carried out with the three cases of technology parameters of devices: (1) current (2015), (2) reduced SC price and (3) reduced all device prices (Table1). Result From the series of analysis, the total system cost can be reduced by installing the appropriate-scale hydrogen energy storage in the future. To achieve self-sufficiency ratio 100%, on the other hand, hydrogen tank cost drastically increased because its capacity got larger to absorb seasonal variation in power generation from SC. Controlling seasonal variation through SC arrangement can reduce the hydrogen tank cost. The cost-competitive system was proposed with the combination of hydrogen energy storage and SC arrangement. Figure 1

Seasonal and regional limits to growth of water-intensive crop farming in Bangladesh

Irrigation-led expansion of crop farming raised demand for groundwater in Bangladesh. This study aimed to reconcile cropped areas compatible to future water demand using secondary data on cropped area, crop yield, food intake, water footprint, rainfall, river-flow, etc. Yearly and seasonal time series were used in forecasting of areas and yields for all categories of crops. Out of total 76.5 bm3 water consumption for crop farming in the early 2010s, 34.1 bm3 was supplied through irrigation of which 79.8% was from groundwater and that would reach at 100.5, 46.6 and 88.2%, respectively in 2029–30. However, pulses, oilseeds, vegetables and potato were identified as feasible crops on the basis of groundwater demand, dietary-balanced self-sufficiency and domestic resource cost ratio. Any reduction of cereal and sugarcane areas over projections and its adjustment with feasible crops would save about one and a half billion m3 of groundwater in dry season. The demand for diversification effort index justified the necessity of initiating special crop diversification projects for the country’s Eastern Hills, North Central and North East regions. Moreover, any initiatives for building water reservoirs might facilitate for sustainable groundwater management in the long run.

The environmental efficiency analysis of China’s power generation sector based on game cross-efficiency approach

China’s unbundling reform in 2002 aimed to introduce competitiveness into the power industry. With the increasing concern about the environmental issue and climate change, the ability to balance the reduction of carbon emissions with economic benefits may to a great extent determine the competitiveness of power generation sector. This study first adopts the game cross-efficiency approach to evaluate the environmental efficiencies of the generation sector in China’s 30 provinces. The results indicate that significant efficiency gap does exist among regions. It then employs a system generalized method of moments model to explore the determinants of their performance while eliminating the associated endogeneity issue. Considering the negative correlation between environmental efficiency and the thermal power ratio, the power mix should be adjusted gradually. The per capita regional GDP and capacity utilization rate are positive factors boosting the environmental efficiency. Accordingly, the incentive policies for clean energy development should be differentiated across regions according to their power mix, self-sufficiency ratio, and economic development situations.

ANALISIS PERBEDAAN KINERJA KEUANGAN SEBELUM DAN SESUDAH PENERAPAN ANGGARAN BERBASIS KINERJA PADA PEMERINTAH DAERAH KABUPATEN TANJUNG JABUNG BARAT

The study this aims to analyze how the performance of local governmentdistrict of West Tanjung Jabung before and after implementation of performancebased
 budgeting. Measuring instrument used is a financial ratio analysis areaconsists of: self-sufficiency ratio, the dependency ratio, the degree ofdecentralization, effectiveness and efficiency of local revenue ratio, the ratio ofthe effectiveness and efficiency of local tax contribution and the degree of publicenterprises. The financial ratios have an important role in determining whether ornot the local government performance. The results show independence region ratio decreases, the dependencyratio increases, the degree of decentralization decreases, the ratio f effectivenessand efficiency of local tax revenue decline merngalami. Based on the analysis, itcan be concluded that the performance of the District government of WestTanjung Jabung after the application of performance-based budget is declining.