Periods Of High Prices Research Articles

Stochastic Optimization of Microgrid Participating Day-Ahead Market Operation Strategy with Consideration of Energy Storage System and Demand Response

More and more attention has been paid to the development of renewable energy in the world. Microgrids with flexible regulation abilities provide an effective way to solve the problem of renewable energy connected to power grids. In this article, an optimization strategy of a microgrid participating in day-ahead market operations considering demand responses is proposed, where the uncertainties of distributed renewable energy generation, electrical load, and day-ahead market prices are taken into account. The results show that, when the microgrid implements the demand response, the operation cost of the microgrid decreases by 4.17%. Meanwhile, the demand response program can transfer the peak load of the high-price period to the low-price period, which reduces the peak valley difference of the load and stabilizes the load curve. Finally, a sensitivity analysis of three factors is carried out, finding that, with the increase of the demand response adjustable ratio or the maximum capacity of the electrical storage devices, the operation cost of the microgrid decreases, while, with the increase of the demand response cost, the operation cost of the microgrid increases and, finally, tends to the cost without the demand response. The sensitivity analysis reveals that the demand response cost has a reasonable pricing range to maximize the value of the demand response.

Integrated Process Design and Control for Smart Grid Coordinated IGCC Power Plants Using Economic Linear Optimal Control

The Integrated Gasification Combined Cycle (IGCC) possesses a number of advantages over traditional power generation plants, including increased efficiency, flex-fuel, and carbon capture. A lesser-known advantage of the IGCC system is the ability to coordinate with the smart grid. The idea is that process modifications can enable dispatch capabilities in the sense of shifting power production away from periods of low electricity price to periods of high price and thus generate greater revenue. The work begins with a demonstration of Economic Model Predictive Control (EMPC) as a strategy to determine the dispatch policy by directly pursuing the objective of maximizing plant revenue. However, the numeric nature of EMPC creates an inherent limitation when it comes to process design. Thus, Economic Linear Optimal Control (ELOC) is proposed as a surrogate for EMPC in the formulation of the integrated design and control problem for IGCC power plants with smart grid coordination.

Bi-Objective Re-Entrant Hybrid Flow Shop Scheduling considering Energy Consumption Cost under Time-of-Use Electricity Tariffs

Re-entrant hybrid flow shop scheduling problem (RHFSP) is widely used in industries. However, little attention is paid to energy consumption cost with the raise of green manufacturing concept. This paper proposes an improved multiobjective ant lion optimization (IMOALO) algorithm to solve the RHFSP with the objectives of minimizing the makespan and energy consumption cost under Time-of-Use (TOU) electricity tariffs. A right-shift operation is then used to adjust the starting time of operations by avoiding the period of high electricity price to reduce the energy consumption cost as far as possible. The experimental results show that IMOALO algorithm is superior to multiobjective ant lion optimization (MOALO) algorithm, NSGA-II, and MOPSO in terms of the convergence, dominance, and diversity of nondominated solutions. The proposed model can make enterprises avoid high price period reasonably, transfer power load, and reduce the energy consumption cost effectively. Meanwhile, parameter analysis indicates that the period of TOU electricity tariffs and energy efficiency of machines have great impact on the scheduling results.

Have the Chinese National Oil Companies Paid Too Much in Overseas Asset Acquisition?

This paper provides both a quantitative and qualitative analysis of whether the Chinese oil companies have “overpaid” than international oil companies in overseas asset acquisitions. By controlling oil price and a number of asset- and deal-specific attributes that are known to affect the valuation of oil and gas projects, we find that while the Chinese companies did not overpay than international oil companies for the period of 2001-2008, there is statistically significant evidence that they overpaid during the 2009-2016 period (mainly 2009-2013). The counterfactual analysis indicates that the Chinese companies paid, on average, 64 percent more than what an international oil company would have paid for the same assets during the post-2008 period. Interviews with industry experts and qualitative analysis suggest that the overpayment mainly results from a series of mistakes due to lack of experience and rush for projects in a period of high oil prices rather than concerns about energy security or other political considerations. The results raise concerns over the efficiency and corporate governance of Chinese state-owned companies, pointing to the need for further reforms.

Forum: Integration of Crop-Livestock Systems: An Opportunity to Protect Grasslands from Conversion to Cropland in the US Great Plains

The Great Plains is a mixture of cropland and grassland mainly used for agricultural purposes, with grasslands under continual threat of conversion to cropland. Agriculturists are advocating for the integration of crop-livestock systems (ICLS) to recouple nutrient cycles, improve biodiversity, and increase resilience of agricultural operations. We address the benefits of ICLS in the Great Plains, contending that focus on improving soil health and financial stability of agricultural operations should reduce the conversion of grasslands to cropland. Using US Department of Agriculture National Agricultural Statistics Service Census of Agriculture survey data from the 1925−2017 category “cropland used only for pasture or grazing,” which represents land that had been cropped but converted to annual/perennial pasture and grazed, we showcase that the number of farms and the land area in this category is a reasonable proxy of ICLS. As expected, ICLS dramatically decreased in the entire United States from 1925 to 1945, but from 1945 to 2002 in the Great Plains ICLS remained relatively constant, providing evidence of sustained crop-livestock integration. Consistent high numbers of beef cows during this period and the wide availability of forages and crop residues for ruminants facilitated opportunities for producers to use ICLS on their individual operations (within farm) or among operations where row crop farmers and forage-based producers integrated beef cattle use across the landscape (among farms). This integration, however, was decoupled from 2006 to 2013, a period of high grain prices. As a result, economic value of grasslands was decreased and conversion to cropland was increased. Thus, conservation efforts in the Great Plains for grasslands should focus on keeping grasslands intact for provision of multiple ecosystem goods and services by emphasizing incorporation of ICLS within and among farms to reduce the risk of converting grassland to cropland.

Impact of food price volatility on child health and education attainment

PurposeThe purpose of this paper is to find the impact of food price volatility on child health and education attainment in urban areas of Pakistan. This research also compares the two variables among the two time periods: the period of low volatile food prices (2014‒2015) and the period of high volatile food prices (2013‒2014). The rate of child immunization and the rate of child school attendance are used as proxies for child health and child education, respectively.Design/methodology/approachThis study employs propensity score matching (PSM) technique introduced by Rosenbaum and Rubin (1983), to overcome the selection bias problem in the observational studies.FindingsThe closing part of the paper concludes that both the rate of child immunization and the rate of child school attendance are significantly poorer for the households of Pakistan in the control period (of high food price volatility) as compared to the treated period (of low food price volatility). After controlling the problem of selection bias through PSM technique, it is found that there is a further increase in the rate of child immunization and the rate of child school attendance. It proves that the data were biased before applying the matching technique.Originality/valueThis study lengthens the literature by identifying the impact of food price volatility on child health and education of urban households of Pakistan, using high frequency data of PSLM/HIES, with the help of semi-parametric technique of matching. This type of micro-level research has not been conducted (nationally or internationally) so far; therefore, it would possibly open a sphere for policy makers to implement the suitable policies.Peer reviewThe peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-04-2019-0275.

Fiscal Regime and Tax Policy in Resource-Rich Countries In The Process Of Globalization: Literature Review

The sudden collapse of oil prices combined with the COVID 19 pandemic is considered to be the worst economic crisis in the history of Resource-Rich Countries. These two events put immense pressure on the economic performance of these countries even with the huge reserves and volume of exports they enjoyed during the past. This raises the question of what are the particularities of these countries that made them very vulnerable to such shocks. This paper is a gathering of multiple studies and reports dealing with the specific topic of Resource-Rich Countries. More precisely, I try to analyze, based on a literature review, the nature of the Fiscal Regime applied in these nations and what makes it different than other countries. In addition, I investigate the Tax Regime applied in Resource-Rich Countries, with an emphasis on observed strengths or weaknesses. I conclude that the Fiscal Regime in Resource-Rich Countries is generally different in many aspects: these countries are subject to severe price volatility, shocks easily affect the economy, and the nature of the Extractive Industry (EI) is very different and needs adequate policy. I also highlight that the Tax System in Resource-Rich Countries is different as well: low investment in human resources and IT and low reliance on tax revenues. This study provides many recommendations to policymakers and authorities in Resource-Rich Countries. The most important is the necessity to implement a Counter-Cyclical Fiscal Policy. Such a measure can enhance savings during periods of high prices while allowing the government to spend more during periods of crisis. In addition, the paper recommends investing more in the tax administration and enhancing the volume of tax revenues as this can allow more diversification. Many other recommendations are presented to help absorb the shocks caused by a severe drop in commodity prices. This paper is a good reference for experts or researchers in the fields of Fiscal Regimes, Tax Policy, and Resource Riche Countries. It is also useful for any research in the domain of the Extractive Industries as it analyzes many of the aspects related to that industry. Keywords: resource-rich countries, fiscal policy, tax policy, countercyclical fiscal policy, mining.

An Optimal Energy Management of Grid-Connected Residential Photovoltaic-Wind-Battery System under Step-rate and Time-of-Use Tariffs

This paper explores optimization for energy management for a given residential application. The study proposes an approach that can minimize the utilization of the grid for electricity usage in the load and maximize the sale from renewable energy (photovoltaic (PV) and wind turbine (WT)). Besides, the battery storage is permitted to sell the excess power during high price period. A time-of-use (ToU) and step-rate tariffs are incorporated in the model to control the efficiency of the utility grid and also to consider the fluctuation of the electricity price. Therefore, two energy management methodologies are developed to adjust the tariffs for great benefits. Â Various residential feed-in tariffs (FIT) are implemented in order to reach the potential of cost-saving and earn more cost-benefit. A typical Moroccan house, containing a grid-connected PV-WT-Battery system, is used for study validation. On the one hand, simulation results show that the developed energy management strategies are effective in controlling the power sources optimally. On the other hand, applying the method under a greater FIT, a lesser requirement of battery capacity will be performed as well as a maximum cost saving. Then, the model as a Non-Linear Problem (NLP) is compared with another existing optimization approach to ascertain the effectiveness and validity of the algorithm.

Prosumer Energy Management Considering Contract With Consumers Under Progressive Pricing Policy

The prosumer market allows prosumers to sell their energy surplus to consumers. The prosumer should offer the amount of energy to sell and its unit price to the contracted consumers while economically operating their system. This paper presents optimal operations and business strategies to maximize the prosumer's benefit by utilizing an energy storage system and ensuring a contract with residential consumers under a progressive pricing policy, where electricity unit price increases with the amount of monthly electricity consumption. By the proposed method, a prosumer under time-of-use pricing scheme stores abundant renewable energy or utility energy at a low price and uses it during a high-price period. Moreover, the proposed optimization can determine the amount of energy and the unit price that the prosumer will offer as a contract in a way that gives consumers strong motivation for the contract; the contract can eventually alleviate consumers' electricity rates by avoiding a high-price zone. For optimization, a quadratic objective problem with quadratic constraints is formulated, and the interior-point algorithm with the Hessian function is used. This study investigates the effectiveness of the proposed method not only under the various penetration rates of renewables but in consideration of uncertainties of renewables and loads. Based on actual field data from Jeju Island of South Korea for 30 days, numerical simulations were performed, and the results indicate that the prosumer's operating costs were reduced by about 12%, simultaneously offering a smaller contract price to the consumer. The Hessian function of the Lagrangian reduced the processing time for the optimization by a maximum of 98.3%. Finally, the ensemble forecast method generating multiple statistical scenarios was tested to address the uncertainty of renewables, showing that the uncertainty had no impact on the contract price and energy.

Producer’s Preference for Price Instability: Revisited

In the debate over producer preference for price instability, Oi argues that producers prefer price instability to stability using only the case where demand shocks generate instability. In this case, storage hurts producers. We use the classic welfare economic framework to consider the more likely scenario where instability is generated by supply shocks and, in the absence of storage, producers prefer production and price instability. However, producers can increase their profits by storing part of the production in the low-price period and releasing stocks in the high-price period. The strong conclusion is that producers prefer, on net, price stability to instability when the possibility for storage exists. Under profit maximization, producers, not governments, engage in storage. Producers prefer to produce under unstable prices, but to sell at stable prices. On net, producers prefer price stability.

PRICE–VOLUME DEPENDENCE OF BITCOIN AND ITS FRACTAL ANALYSIS

Nowadays Bitcoin as cryptocurrency takes a significant place on the global financial markets. This paper analyzes the Bitcoin closing prices and traded volume during the period from December 28, 2013 to January 22, 2019. This period is known as a period with rapid increasing of the Bitcoin closing prices, mainly in the second half of the year 2017. The aim of this paper is twofold. First, we compute the Hurst coefficient to discover the close price dynamics and traded volume using a fractal point of view. We have discovered an anti-persistent behavior in the traded volume and random character of bitcoin closing prices. Second, we propose an analysis of the relationship between the close prices and traded volume. Our findings show how changes in the high-price period differ from changes in the low-price period. We also found that high prices caused investors to be afraid to trade due to possible rapid decrease in bitcoin closing prices.

Demand Response of an Industrial Buyer considering Congestion and LMP in Day-Ahead Electricity Market

Abstract This paper proposes a methodology for developing Price Responsive Demand Shifting (PRDS) based bidding strategy of an industrial buyer, who can reschedule its production plan, considering power system network constraints. Locational Marginal Price (LMP) methodology, which is being used in PJM, California, New York, and New England electricity markets, has been utilized to manage the congestion. In this work, a stochastic linear optimization formulation comprising of two sub-problems has been proposed to obtain the optimal bidding strategy of an industrial buyer considering PRDS bidding. The first sub-problem is formulated as to maximize the social welfare of market participants subject to operational constraints and security constraints to facilitate market clearing process, while the second sub-problem represents the industrial buyer’s purchase cost saving maximization. The PRDS based bidding strategy, which is able to shift the demand, from high price periods to low price periods, has been obtained by solving two subproblems. The effectiveness of the proposed method has been tested on a 5-bus system and modified IEEE 30-bus system considering the hourly day-ahead market. Results obtained with the PRDS based bidding strategy have been compared with those obtained with a Conventional Price-Quantity (CPQ) bid. In simulation studies, it is observed that the PRDS approach can control the LMPs and congestion at the system buses. It is also found that PRDS can mitigate the market power by flattening the demand, which led to more saving and satisfying demand.

Role of land quality in corn acreage response to price and policy changes: evidence from the Western Corn Belt

Land quality influences how farmers allocate croplands in response to market forces. Farmers in the Western Corn Belt (WCB) have historically utilized the highest quality lands for corn cultivation, putting lower quality lands to other uses. This paper questions whether high corn prices influenced expansion of corn cultivation on lower quality lands, and the role played by US biofuel policy in such land use change. Using three decades of data, I estimate that the proportional change in corn acreage to rising corn prices is nearly three times larger in counties with lowest land quality versus those with the highest land quality. This variable response, however, is driven by the changes in cropland use for corn cultivation after 2006, the period following the change in US biofuel policy, and punctuated by two crop price spikes. Marginal agricultural lands and other lower quality lands, such as grasslands used for range or pasture, are therefore prone to conversion into corn cropping disproportionately during high price periods. High price responsiveness of lower quality lands also suggests these lands may cycle in and out of corn cropping opportunistically. This has implications for marginal land availability for bioenergy crops, and poses environmental concerns to the extent lower quality lands are also more environmentally sensitive.

Dynamic evolution characteristics of European union emissions trade system price from high price period to low price period

Carbon market is a valid measure for promoting green and low-carbon development, and price is the core of market mechanism. In this work, combining directed limited penetrable visibility graph and coarse graining method, a new method is proposed to identify the potential periods and dynamic evolution characteristics of carbon price, which opens up a new perspective for government and investors to understand evolution characteristics and prevent risks. At the same time, a empirical analysis is conducted based on EU ETS daily price from September 29, 2009 to September 29, 2017, and the dynamic fluctuation characteristics of carbon price from high price period to low price period are obtained.

Economic optimization of distributed embedded battery units for large‐scale heating, ventilation, and air conditioning applications

AbstractEnergy costs of space heating and cooling systems can be significantly decreased using energy storage to shift the load from periods of high prices to periods of low prices. In this work, an economically optimal method of controlling large systems with distributed embedded batteries units is proposed. The control system with load shifting outperforms the conventional trade‐off curve between cost and occupant comfort. Remarks are also made about the economic viability of these systems moving forward.

Smart home energy optimization with incentives compensation from inconvenience for shifting electric appliances

Demand management programs help utilities to reduce the load demand during high wholesale electricity price or system peak periods to maintain the system reliability and operational security. The challenge here is to properly address the customers’ inconvenience to encourage them to participate and meanwhile satisfy the required demand reduction efficiently. To this end, we propose a new incentive-based demand management scheme for schedulable appliances in a residential community. The proposed scheme is designed to provide scalability to the system. Different from existing literature, a new compensation scheme is adopted for the shifting of task-based appliances based on the level of inconvenience. The potentials of the schedulable appliances to contribute during the demand reduction event are assessed with a modified demand response potential. In this approach, the utility sends command and consumption limit to several controllers to perform the energy optimization. Participating customers are benefited with financial compensation along with minimized privacy concerns in the proposed centralized approach. Considering different demand reduction events within a month, the electricity bill with the proposed scheme is compared with the electricity bill from time-of-use (TOU) tariff-based optimization scheme and also with the base case (i.e., without any energy optimization scheme). Comparison of monthly electricity costs shows that the proposed scheme can save 11.3% on average more than the base case, and also the proposed scheme can save 6.2% on average more than the TOU tariff-based optimization.

Optimal short-term coordination of water-heat-power nexus incorporating plug-in electric vehicles and real-time demand response programs

In recent years, the population growth has caused the water and energy shortages. Therefore, the current paper proposes a novel method for day-ahead optimization of integrated water-heat-electricity systems with the aim of minimizing the fuel cost of the desalination, heat treatment and power production units. The technical limits of the power only units, combined power and water generation units, cogenerators of heat and electricity, heat only units, and the seawater purification process are incorporated in optimization problem. In addition, a real-time demand side management strategy is applied on heat, pure water and power loads to reduce the objective cost function as low as possible by shifting a percentage of each demand from peak periods to mid or off peak hours. Moreover, aggregators of pure electric vehicles participate in bulk energy management by charging electricity during off-peak low-price hours and discharging it over the on-peak high-price periods. To validate the feasibility and cost-effective performance of the water-heat-power hub system, a mixed-integer non-linear program is developed by generalized algebraic mathematical modelling system (GAMS) optimizer and solved by branch-and-reduce optimization navigator (BARON) tool. The ramp down and ramp up limits of the thermal power plants, generation capacity of water/heat/power producers, and the load-generation balance criterion are considered as optimization constraints. It is found that $659,573 cost saving is obtained due to participation of PEVs and DRPs in trigeneration process.

ФАКТОРЫ ПОТРЕБЛЕНИЯ ВОЗОБНОВЛЯЕМЫХ ИСТОЧНИКОВ ЭНЕРГИИ НА МЕЖДУНАРОДНОМ УРОВНЕ: РАЗРАБОТКА МОДЕЛИ ОЦЕНКИ

Based on the use of panel data, the work establishes the relationship between the development of renewable energy sources and (1) the price of fossil energy, (2) the supply of oil and gas consumption through its own production, (3) the factor of the country's technological development and (4) the influence of non-competitive political institutions. The period of high prices for fossil energy (1999-2014) became the catalyst for changes in the structure of the energy balance, especially in Europe, with an increase in the production of renewable energy. However, the fall in prices in 2014 - to the present has led to stagnation in the production of renewable energy with a rapid increase in the use of fossil fuels. In the context of this work, the significance of the factors under study on the consumption of renewable energy sources is proved.

Impacts of Residential Energy Management on Reliability of Distribution Systems Considering a Customer Satisfaction Model

Residential energy management (REM) systems facilitate the application of residential demand response programs to manage the increasing demand of electricity in power systems. The load curtailment at high price periods and the load shift from high-price to low-price periods are the main results of REM implementation, which may improve the technical and economical operation of the distribution systems. Customers' satisfaction should be considered in the REM procedure to motivate the customers to respond to the received price signals. This paper proposes an optimization-based REM to minimize not only the customer's energy cost but also customer dissatisfaction, which is modeled as a function of load curtailment. In addition, the impact of broad application of REM in bus 6 of RBTS is studied on the reliability of a distribution system. To this end, two different methods for reliability evaluation are used to show the effect of load shift and load curtailment on the energy not supplied by the distribution system. The results verify the validity and effectiveness of the proposed REM approach and show the impact of application of REM programs with different penetration levels on the reliability of the distribution system.

Energy flexibility of a nearly zero-energy building with weather predictive control on a convective building energy system and evaluated with different metrics

The implementation of energy flexibility using thermal storage of building structure is one of the key solutions for buildings in contributing to a stable exploitation and distribution of renewable energy. The objective of this study is to investigate the performance of energy flexibility of a nearly zero-energy building with weather predictive control of a convective building energy system. Analysis and comparisons have been conducted on different control strategies to evaluate the influence of the strategies on the energy flexibility. The investigated control strategies of a heating and cooling system include: normal control (reference case), adjustment of set-points for heating and cooling and adjustment of set-points together with a rule-based weather predictive control strategy.The performance of buildings on conducting energy flexibility can be assessed from different perspectives. Comparison of the performance and potential is conducted with different evaluation metrics that represent benefits of different parties (power grid, building owners or tenants, building users), including the ability of power shifting, the efficiency of energy shifting, economic benefits and comfort level.The study shows that, compared to the reference case, a maximum decrease of around 0.005 kW/m2 in peak power during high-price periods can be achieved by changing the set-points of heating and cooling according to the energy price. Around 80% of the energy consumption during high-price periods can be removed by the control strategies. However, energy cost has increased from 0.499 EUR/m2·per·year to 0.703 EUR/m2·per·year by implementing a simple control strategy. By adding weather predictive control on the simple strategy, the energy cost is 26% lower than the simple control strategy but slightly higher than the case that is without flexibility control.