A Study on Selecting Greenhouse Gas Reduction Options: A Simulation Analysis for Vietnam

When it comes to greenhouse gas (GHG) mitigation, both bottom-up and top-down policies have limitations. Bottom-up policies are region-specific and cannot be applied at the national level. Top-down policies may not balance the considerations of economic growth and the environment. Therefore, a combined approach is necessary. This Vietnamese case study investigates optimal GHG mitigation options for both economic development and emission reduction by simulating four scenarios characterized by the different carbon tax and subsidy rates. Interventions, like replacing old buses with low-carbon buses and conventional electricity generation with solar power, are considered in a dynamic input–output framework. The objective function is Green GDP—industries’ total value added reflecting GHG emissions’ social cost. The simulation model comprises four cases: business as usual, low subsidy rate (up to 10%), medium subsidy rate (up to 20%), and high subsidy rate (up to 30%), which are analyzed on parameters, including economic development, GHG emissions, and development of innovative sectors, like transportation and electricity. In three cases with different subsidy rates, the optimal carbon tax is simulated at the rate of USD 1/tCO2 equivalent, the lowest rate among the world’s current carbon prices. In addition, the medium subsidy (up to 20%) option yields the most competent scheme, with the highest GHG emission reduction and economic development effectiveness.

Linking a sugar-sweetened beverage tax with fruit and vegetable subsidies: A simulation analysis of the impact on the poor

Background US individuals, particularly from low-income subpopulations, have very poor diet quality. Policies encouraging shifts from consuming unhealthy food towards healthy food consumption are needed. Objectives We simulate the differential impacts of a national sugar-sweetened beverage (SSB) tax and its combination with fruit and vegetable (FV) subsidies targeted to low-income households, on SSB and FV purchases of lower and higher SSB purchasers. Design We considered a one-cent-per-ounce SSB tax and two FV subsidy rates of 30% and 50% and used longitudinal grocery purchase data for 79,044 urban/semiurban US households from 2010-2014 Nielsen Homescan. We used demand elasticities for lower and higher SSB purchasers, estimated via longitudinal quantile regression, to simulate policies’ differential effects. Results Higher-SSB purchasing households made larger reductions (per adult equivalent) in SSB purchases than lower SSB purchasers due to the tax (e.g., 4.4 oz/day at SSB purchase percentile 90 vs. 0.5 oz/day at percentile 25; p < 0.05). Our analyses by household income indicated low-income households would make larger reductions than higher-income households at all SSB purchase levels. Targeted FV subsidies induced similar, but nutritionally insignificant, increases in FV purchases of low-income households regardless of their SSB purchase levels. Subsidies, however, were effective in mitigating the tax burdens. All low-income households experienced a net financial gain when the tax was combined with a 50% FV subsidy, but net gains were smaller among higher SSB purchasers. Further, low-income households with children gained smaller net financial benefits than households without children and incurred net financial losses under a 30% subsidy rate. Conclusions SSB taxes can effectively reduce SSB consumption. FV subsidies would increase FV purchases, but nutritionally meaningful increases are limited due to low purchase levels pre-policy. Expanding taxes beyond SSBs, larger FV subsidies, or subsidies beyond FVs, particularly for low-income households with children, may be more effective.

Will Port Integration Help Reduce Carbon Emissions and Improve Social Welfare?

In the context of competition between two ports in Cournot, we studied optimal decision-making processes for the government and the port in four different situations before and after the integration of the port based on the subsidy and carbon tax mechanism. We analyzed the impacts of the carbon tax rate and emission reduction subsidy rate on social welfare and determined the optimal carbon tax rate, the optimal emission reduction subsidy rate, the optimal carbon emission level, and the optimal social welfare level in different situations. We also compared the optimal social welfare level and the optimal carbon emission level of the four situations before and after the integration. This research can be used as a policy reference for the government for the formation of environmental policies based on the goal of maximizing social welfare, and it could also be used for the port’s internal decision-making when the environmental policy has been set.

Studying the Complexity of Multichannel Supply Chain with Different Power Structures Under Carbon Subsidy Policy

The game characteristics and equilibrium strategies of a triple-channel supply chain under the carbon subsidy policy are studied in this work with three different game power structures. There are simultaneous decision-making, manufacturer-dominated market and retailer-dominated market. The decision mechanism for order quantity of manufacturer and dual-channel retailer, is discussed. Meanwhile, their complex dynamic characteristics are studied. It is found that when the government implements dual low-carbon subsidies, the supply chain system in which the manufacturer dominates the market is more stable. The government should pay attention to the power structure of the market to determine an appropriate subsidy rate. The over-adjustment of order quantity from manufacturer’s direct sales channel and retailer’s online channel both will lead to large periodical fluctuations in the system, and even bifurcation and chaos. These will cause substantial fluctuations and even loss in the profits of supply chain companies. This analysis shows that delayed feedback can effectively stabilize the periodic bifurcation and chaos in the system.

Determinants of farm profitability in the EU regions. Does farm size matter?

Farms in the European Union come in a wide variety of sizes and the effect of farm size on profitability (return on assets – ROA) has not been sufficiently investigated. The principal goal of this paper, therefore, is to study the determinants of farm profitability using the panels of the Farm Accountancy Data Network (FADN) on farms of different economic size between 2007 and 2018. We use a profitability function based on ratios that show the production and financial management strategies used by the farms. We also analyse the impact of subsidies under the Common Agricultural Policy (CAP). To deal with endogeneity, we run dynamic panel models using the system generalised method of moments (sys-GMM) estimators. We highlight the important role of the high level of equity turnover. An increase in production relative to the farm's equity plays a crucial role in the growth of profitability for all groups of farms, but it is especially important for smaller entities. In addition, farm managers should control the level of debt since the debt-to-asset ratio is a highly significant negative determinant of farm profitability in most of the groups. The increase in subsidy rate generally translates into higher ROA, but this variable has a negative impact across the largest holdings.

Effect of Optimal Subsidy Rate and Strategic Behaviour of Supply Chain Members under Competition on Green Product Retailing

This paper investigates the impact of the subsidy and horizontal strategic cooperation on a green supply chain where two competing manufacturers distribute substitutable green products through exclusive retailers. Models are formulated in three-stage game structures in five different scenarios, where the government organization determines optimal subsidy by pursuing social welfare maximization. Both manufacturers invest in improving green quality levels of products. The study aims to explore the advantage of vertical integration and strategic collusion from the perspective of green supply chain practice in the presence of subsidy. The key contributions from the present study indicate that under competition, members of both supply chains are able to receive higher profits through horizontal collusion, but green quality levels of the product remain suboptimal. If upstream manufacturers cooperate, government subsidy does not necessarily improve product quality level, and the amount of government expenditure increased substantially. By comparing outcomes where members are vertically integrated with scenarios where members make strategic collusion, we found that the former might outperform by later. Cross-price sensitivity appears as a significant parameter affecting supply chain members’ performance and the amount of government expenditure. Cooperation between members at the horizontal level is a more robust strategic measure than vertical integration if consumers are highly price-sensitive.

Optimization of Shore Power Deployment in Green Ports Considering Government Subsidies

Shipping trade and port operations are two of the primary sources of greenhouse gas emissions. The emission of air pollutants brings severe problems to the marine environment and coastal residents’ lives. Shore power technology is an efficient CO2 emission reduction program, but it faces sizeable initial investment and high electricity prices. For shipping companies, energy such as low-sulfur fuels and liquefied natural gas has become an essential supplementary means to meet emission reduction requirements. This research considers the impact of government subsidies on port shore power construction and ship shore power use. It constructs a multi-period dual-objective port shore power deployment optimization model based on minimizing operating costs and minimizing CO2 emissions. Multi-combination subsidy strategies, including unit subsidy rate and subsidy demarcation line, are quantitatively described and measured. The proposed Epsilon constraint method is used to transform and model the dual-objective optimization problem. Numerical experiments verify the effectiveness of the model and the feasibility of the solution method. By carrying out a “cost-environment” Pareto trade-off analysis, a model multi-period change analysis, and a subsidy efficiency analysis, this research compares the decision-making results of port shore power construction, ship berthing shore power use, and ship berthing energy selection. Government subsidy strategy and operation management enlightenment in the optimization of port shore power deployment are discussed.

Smart hedging against carbon leakage

Policy makers in the EU and elsewhere are concerned that unilateral pricing of the carbon externality induces carbon leakage through relocation of emission-intensive and trade-exposed production to other regions. A common measure to mitigate such leakage is to combine an emission trading system with output-based allocation (OBA) of allowances where the latter works as an implicit production subsidy to regulated industries. We show analytically that it is optimal to impose in addition a consumption tax on the OBA goods (i.e., goods that are entitled to OBA) at a rate which is equivalent in value to the OBA subsidy rate. The explanation is that the consumption tax alleviates excessive consumption of the OBA goods, which is a distortionary effect of introducing output-based allocation. Using a multi-region multi-sector computable general equilibrium model calibrated to empirical data, we quantify the welfare gains for the EU of imposing such a consumption tax on top of its existing emission trading system with OBA. We run Monte Carlo simulations to account for uncertain leakage exposure of goods entitled to OBA. The consumption tax increases welfare whether the goods are highly exposed to leakage or not, and hence can be regarded as smart hedging against carbon leakage.