Feed-in Research Articles

No more need for CfDs or feed-in tariffs?

No more need for CfDs or feed-in tariffs?

Application of a Community Battery-Integrated Microgrid in a Blockchain-Based Local Energy Market Accommodating P2P Trading

This paper presents the application of a community battery energy storage system (CBESS)-integrated microgrid (MG) in a blockchain-enabled local energy market (LEM). The proposed LEM balances the community energy requirement while facilitating frequent peer-to-peer (P2P) energy transactions between several energy users in the presence of both energy supplier and energy operator. The architecture is formulated by taking a number of local market and network constraints, that include residential battery energy storage system (RBESS) constraints; CBESS constraints; P2P traded price constraints; P2P traded power constraints; margin constraints of the stakeholders; power grid export and import constraints; and network energy balance constraints, so as to not only incentivise energy users but also reduce import/export from/to power grid while keeping the margins of energy supplier and energy operator unaffected. Different types of transactions data including energy users’ P2P pricing bids and P2P traded energy volume are also stored in the blockchain database. Further, the developed LEM framework is also validated through a case study executed on an actual Australian power grid network, comprising 260 residential energy users; two energy suppliers; an energy operator; and a CBESS, and the performance of the proposed P2P trading-based LEM strategy is compared with the existing business-as-usual (BAU) that directs energy users to buy/sell energy at the time-of-use (ToU)/ feed-in-tariff (FiT) rate. The extensive and comparative simulation results confirm the superior performance of the proposed LEM mechanism in terms of minimising energy users’ electricity bill; lowering power grid import and export; and retaining margins of energy suppliers and the energy operator; and thus, emphasise its application suitability in the current electricity market.

Comparisons of Auction Designs Through Multiagent Learning in Peer-to-Peer Energy Trading

Distributed energy resources (DERs), such as solar panels, are growing rapidly and reshaping power systems. To promote DERs, utility companies usually adopt feed-in-tariff (FIT) to pay DER owners (aka prosumers) fixed rates for supplying energy to the grid. As an alternative to FIT, consumers and prosumers can trade energy in a peer-to-peer (P2P) fashion. In this paper, we focus on a P2P market using double auctions, in which the payoffs of energy consumers/prosumers are determined by their bids and auction mechanisms. Special features of a P2P energy auction, however, including zero marginal cost and publicly-known reserve prices, may invalidate many theories on auction design and hinder market development. We discuss the impacts of such features on four specific clearing mechanisms: <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> -double, Vickrey, McAfee and maximum volume matching (MVM). Furthermore, we propose an automated bidding framework based on multi-agent, multi-armed bandit learning, in which each agent only needs to utilize their own bidding history to determine how to bid in the next round through certain regret-minimizing algorithms. Numerical results show that the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$k$ </tex-math></inline-formula> -double and McAfee auction appear to perform better in terms of bidders’ surplus. However, if the auctioneer also requires compensation, MVM can yield the most profit for the auctioneer.

Feed-in tariffs for solar energy in Thailand

Feed-in tariffs for solar energy in Thailand

Sales of electricity from cogeneration plants on organized markets in Southeast Europe

Volatile energy prices in the past period, force countries and their market participants to find alternative and cheaper sources of electricity production, while respecting defined environmental principles. Serbia is one of the rare European countries that uses its reserves of dissolved gas in the heat and electricity production. Combined heat and power plants, although in an almost negligible amount, contribute to the diversification of Serbia's production mix. With the presence of organized markets and local power exchanges, sale of electricity from combined heat and power plants is guaranteed for all producers who do not meet the conditions for acquiring the right to feed-in tariffs. The aim of this paper is to analyze the most profitable sale on the power exchanges of the domestic market and the region, specifically the markets of Serbia, Croatia, Hungary, Romania, and Bulgaria. The calculation methodology itself implies the use of average monthly price value for the observed markets, in the period of the past three years and nine months. In addition to the aforementioned, the costs of cross-border capacities were considered. In order to have a clearer overview of the results and the possibility of applying the methodology, the amount for calculation is 1 MWh. Costs and revenues related to negative and positive balance energy deviations are excluded from the analysis. Results showed that sale of electricity is most profitable on Serbian power exchange.

Joint Management Committee in Renewable Energy Projects

The Renewable Energy (RE)sector has been developed in some degree by government policies, but tools must be applied on a private-commercial scale for this sector to grow even more. These tools can be applied through the contractual relationships between the participants in a RE project. Many contracts are involved in a RE project that are not integrated in such a way that cooperation for improving risk management is possible. To reach that goal some contractual institutions are needed. One of them is the joint management committee (JMC). JMC has been used in the context of oil and gas contracts for a long time. And it has been one of the reasons that petroleum projects despite having high risks and long terms, thrive. In this research, the application of a similar structure for renewable energy has been studied and a format for that has been proposed. Hence, it has concluded that this structure can bring authorities, RE producers, and utilities together, and provide integrity to the contracts involved with a RE project. Key words: renewable energy; joint management committee; contractual fiscal regime; feed-in tariff; electricity markets.

Urban expansion of Energiewende in Germany: a systematic bibliometric analysis and literature study

BackgroundDespite Germany’s world leadership of Energiewende, there have been mounting challenges, such as the slowdown of German renewable energy growth since 2017, when the Merkel administration dramatically changed the German renewable energy promotion policy from feed-in tariffs to competitive auctions. These challenges pose important research questions about whether and how an emerging urban expansion of Energiewende can serve as a vital solution to counteract the challenges to the energy transition. Answering these research questions provides a unique opportunity to explore the academic and historic foundations of the energy transition and its urban expansion, the emerging events that exemplify urban expansion, and the viable solutions this growing trend of urban expansion might be able to provide to the challenges to the German energy transition.MethodsThis paper conducted visual and manual bibliometric analyses, examined the results of case studies, and reviewed secondary literature and data on urban expansion of German Energiewende.ResultsBy analyzing the bibliometric and investigative results, this paper identified political, socioeconomic, and technological challenges to Energiewende and a new trend of solar energy expansion in German cities aimed at meeting Germany’s carbon neutrality targets by 2045. The new trend of the urban expansion of the German energy transition manifests itself in the focused research efforts on identifying the vast untapped potential on new building rooftop areas in most populous German cities and/or detached and two-family houses in Germany and the recent booming of building-related solar PV and heating mandates in German cities and states, the expanding solar heating and cooling systems, and the government policy support at various levels in this urban expansion through aggressively strengthening climate and renewable energy targets.ConclusionsIn search for answers to the recent challenges of Energiewende in Germany, this paper conducted both visual and manual bibliometric analyses and applied desk research and reviews of secondary literature and data. This paper found an emerging trend of the urban expansion of Energiewende, including the awareness of the vast potential and gap of urban solarization and the enhanced urban municipal policies, actors, actions, and accomplishments of exploiting this potential. These findings were based on academic knowledge on the German energy transition and contribute to expanding this academic knowledge. To help more effectively exploit the vast potential in solarizing all German cities, especially the largest ones, this study recommends that further research more closely track the progress of this trend and apply more quantitative tools and approaches in future tracking.

Quantifying the importance of feed-in tariffs to wind power development in China.

Governments worldwide often provide subsidies to renewable energy for reasons such as climate change mitigation and environmental pollution reduction. However, the importance of such subsides is not well understood and much debated. In this study, 109 monthly observations of the installed wind power capacity at the provincial level were used to assess the most important wind power subsidy policy in China-feed-in tariffs, while controlling for other confounding factors, such as technological change, local energy mix, and wind curtailment. The long panel regression results indicate that with other factors unchanged, an increase of 0.1 yuan/kWh in feed-in tariffs added 7.4-9.6 GW of wind capacity to China's national wind power market annually, higher than most of the estimates in the literature, but more consistent with the fast wind capacity development in China. Without the FIT subsidy, China's current wind power market size would likely be approximately 80% smaller. Our findings can be used to predict the impact of future cost reduction of wind technologies, and examine the interconnected relationships between wind capacity development, subsidy burden, and wind curtailment issues.

Techno-economic feasibility analysis of grid-connected residential PV systems in Algeria

Small-scale photovoltaic (PV) power systems have been proven to be successful in generating electricity, conserving fossil fuels, and reducing greenhouse gas emissions in the residential sector, which is one of the largest consumers of energy. In Algeria, to reduce energy consumption in this sector, the authorities are considering implementing a policy that would encourage grid-connected residential PV systems. This paper presents a techno-economic assessment of grid-connected residential PV systems in four climate zones in Algeria. This work was performed using HOMER software for two different PV system configurations, grid/PV and grid/PV/battery. The technical performances of the considered systems were evaluated through the assessment of the self-consumption and self-sufficiency, while the net present value (NPV), internal rate of return (IRR), profitability index (PI), and discounted payback period (DPBP) were used to determine their feasibility. A sensitivity analysis was carried out to evaluate the effects of feed-in tariff (FiT), battery costs, and PV array capacity on the profitability of the systems. The results revealed that the grid/PV systems are technically and economically feasible in all of the four climate zones. For the grid/PV/battery systems, the grant of battery costs and the development of a regional FiT system are recommended. This article provides a tool for policymakers to assess the technical and financial performance of residential solar PV systems to develop adequate policy supports and tariff structures for Algeria.

Economic Assessment of Operation Strategies on Park-Level Integrated Energy System Coupled with Biogas: A Case Study in a Sewage Treatment Plant

Operation strategies for a park-level integrated energy system (PIES) in terms of carbon prices and feed-in tariffs, have not been adequately studied. This paper addresses this knowledge gap by proposing operation strategies based on the PIES driven by biogas, solar energy, natural gas, and the power grid. Meanwhile, the electricity-driven dispatching strategy (EDS), thermal-driven dispatching strategy (TDS), cost-driven dispatching strategy (CDS) are compared to assess their impacts on operation cost, carbon dioxide emissions, etc. The flexibility and complementarity of the three operation strategies in energy supply are analyzed in detail. The results indicated that biogas was the main energy supply fuel, accounting for 46% to 72% of the total energy supply. About 33% to 54% of electricity was transmitted to the grid each month using the TDS. The annual initial capital cost of the CDS was only 1.39% higher than that of the EDS. However, the annual operation cost of the EDS was 16.86% higher than that of the CDS. The emissions of the EDS were the lowest, and the CDS had 38.51% higher emissions than the EDS. In the CDS, the ratio of carbon emission costs to operation costs was as high as 0.80 when the carbon tax reached USD 100/ton. The carbon tax had a greater impact on the CDS than the other strategies. Feed-in tariffs had a greater impact than the carbon tax on the TDS. This study provides an effective method for the selection of optimal operation strategies in regards to carbon prices and feed-in tariffs.

Determinants of Return-on-Equity (ROE) of Biogas Plants Operating in Poland

Poland has a large potential for biogas production from agricultural sources and food waste. This potential is still poorly used. There are many reasons for this state of affairs. We can indicate both the policy of the state towards renewable energy sources (RES) with a small amount of energy from biogas contracted at auctions, investment risk, and especially low return on investment in the absence of investment support. An important reason is also the limited state budget. The purpose of this work was to determine the endogenous factors that determine ROE, the direction of the impact of these factors, as well as the strategy of biogas plants in shaping the ROE level. The DuPont model was used in the analysis of ROE changes. We used the deviation method to determine the impact of the various factors on ROE. Against the background of the energy sector in Poland, the value of ROE in the examined biogas plants should be considered satisfactory, and in 2020 it was, on average, 13.9%. The decrease from 17.2% in 2019 occurred despite the increase in energy prices and the increase in the net profit margin (NPM). It resulted from the reduction of ROE’s financial leverage through external capital. A high level of debt characterized the examined biogas plants, and the pursuit of risk reduction and debt reduction negatively impacts on ROE. This may indicate the need for state investment support at the plant construction stage or low-interest investment loans to develop biogas plants. In addition, using only price guarantees under the feed-in tariffs, with dynamic changes in costs, may bring the industry a relatively high investment risk compared to other RES, where the operational costs during the lifetime are low, as it is in PV or wind systems.

Potential analysis of hydrogen energy technology in the power grid based on carbon tax: A case study in Japan

Electrolytic hydrogen storage technology of renewable energy is considered as one of the important measures to realize the high proportion of renewable energy. However, developing this technology has been slow due to the cost. This study proposes highlighting the environmental advantages of renewable power combined with a carbon tax at the national level to expand the application space of hydrogen storage technology. First, the economy and technical characteristics of hydrogen storage technology and conventional energy-storage technology were compared. Then, Japan's top 10 power companies, which account for 90% of the power supply, were taken as the research objects. The proportion of change in renewable power after introducing a carbon tax was studied, taking the weighted minimum of the feed-in tariffs as the optimization objective. The contribution of hydrogen storage technology to the change in renewable power share was analyzed. Next, a sensitivity analysis was conducted on the fossil energy price and cost of renewable power equipment that affects the research. Finally, the contribution of a carbon tax and hydrogen storage technology to Japan's emission reduction target was calculated and analyzed. The results showed that the characteristics of long-distance transportation of hydrogen energy and making renewable energy have economic advantages under the current carbon tax (5–6 JPY/kg-CO2). The cost of liquified natural gas (LNG) and the investment of photovoltaic (PV) have a significant impact on the weighted minimum feed-in price, which can make the development of hydrogen storage technology no longer rely on the setting of carbon tax. The results obtained in this study provide a theoretical reference for the application of hydrogen storage technology in the high proportion of renewable energy consumption. At the same time, it can also provide data reference for large-scale construction of renewable energy in regions where solar and wind energy resources are not excellent.

Independent Power Producer Approach to Optimal Design and Operation of IES with Wind Power Plants

In South Korea, Renewable Energy Sources (RES) have been increasing with the application of energy policies, such as Feed in Tariff (FIT) and the Renewable Portfolio Standard (RPS). However, a rapid increase in RES supply leads to an uncertain power supply due to the intermittent output of RES. A representative example is the curtailment of Wind Turbines (WT), which frequently occurs in Jeju Island, South Korea. The proportion of RES power on Jeju Island is 67%, and there are cases where WT is curtailed among the operable sections to maintain the balance of power supply and demand. This paper applies Power-to-Gas (P2G) technology to hydrogenate, store, and utilize unused power to solve this problem. In this paper, Aewol-eup in Jeju Island is selected as a target site for case study. An Integrated Energy System (IES) for various energy operations is designed to control RES output. This paper proposes the optimal facility configuration and finally drives the optimal design and operation solution of IES by analyzing the objective functions and focusing on the Independent Power Producer (IPP) perspective.

A stochastic offering approach for photovoltaic power plants in day-ahead and balancing markets

Given the increasing share of photovoltaic (PV) power plants in power generation worldwide, this paper presents an optimal offering strategy based on artificial neural networks (ANNs) in both day-ahead (DA) and balancing markets. A PV plant faces a variety of uncertainties at the time of participating in the electricity market, including its production level, balancing market demand, market price, and offering behavior of the competitors. To manage all types of uncertainties together, a combination of scenario-based approach and decentralized equivalent competitor concept is proposed in a novel offering strategy for PV plants. The approach is implemented on the IEEE 30-bus system and two case studies, namely, with and without an energy storage system, are considered for result analysis. The results show a 9.6% of profit increase while the PV plant employs the proposed approach in comparison with the premium feed-in tariff method. Furthermore, in the case where the PV plant is equipped with battery storage with a charging capacity equal to 50% of the maximum production capacity of the PV plant, using the proposed approach for scheduling the battery, the profit has increased by 2.5%. To investigate the performance of the proposed approach in terms of robustness a numerical comparison is conducted. For this purpose, the proposed approach has been compared with the affinely adjustable robust offering strategy method in case of robustness. Numerical results show that the effectiveness of the proposed method in the worst case (maximum considered level of uncertainty) is 77% of the best case (without uncertainty), while this is 36% for the affinely adjustable robust offering strategy-based method. The conducted investigations show that the proposed offering approach, while efficient, is robust against a high level of uncertainties.

Combined third-party ownership and aggregation business model for the adoption of rooftop solar PV–battery systems: Implications from the case of Miyakojima Island, Japan

Solar photovoltaics with behind-the-meter energy storage systems are gaining recognition as net energy billing replaces feed-in tariffs because they can unlock demand-side flexibility, keep grid stability, and enhance the resilience of end users. However, incumbent grid companies tend to prioritize grid stability and reliability and disregard resilience, which decreases end users’ perceived benefits, intention, and adoption of the systems. The combined third-party ownership–aggregation business model could drive adoption because it can enhance grid stability and reliability, and resilience at the same time. This study explores how the model works to increase the intention and adoption, and what policies and regulations are required to enable the model to mitigate the conflict of interest taking Miyakojima Island in Japan as a case study. The study finds that the model can increase adoption by reducing perceived risks. Policy and regulations, and resistance and inert of incumbent grid companies block the model from effectively working to change the benefit-sharing. Science-based regulations on the use of energy storage systems during power outages, stringent policy implementations of updated renewable energy targets and the 2050 carbon neutrality, and detailed time-of-use pricing can change the benefit-sharing in favor of end users and increase adoption.

Techno-economic analysis of an offshore wind farm on the eastern Mediterranean Sea coast.

Turkey has rapidly become one of the top markets for onshore wind energy with a 10 GW onshore wind power installation, a significant accomplishment for the nation. It means that Turkey's wind energy capacity has more than tenfold increase in the last 10years. Despite the fact that Turkey has no offshore wind farms, research has indicated a significant and untapped energy potential. This work provides a comprehensive techno-economic analysis of the Samandag Offshore Wind Farm (OWF) project in Turkey. To undertake an economic feasibility study under different Feed-in Tariffs (FiT) and discount rates, a discounted cash flow economic model is utilized. This study takes into consideration the economic indicators utilized in decision-making processes from the perspective of an OWF investor. The planned OWF project is shown to be economically viable only provided specific techno-economic prerequisites are satisfied. Samandag City has a lower levelized cost of energy (LCOE), which is roughly $69.97/MWh, according to the findings. However, the findings show that the net present value (NPV) is very sensitive to discount rates and FiT. The goal of this research is to contribute scientifically to the development of offshore wind energy in Turkey.

A Study on Regulations Mandating Obligation on Renewable Energy in Taiwan

The shift toward renewable energy has become a global trend today. In the past, power producers or the private sector were encouraged to install renewable energy equipment mainly through incentives (e.g., feed-in tariff, tax credits). Some countries also impose “renewable portfolio standards”, which mandate power producers to include RE. However, it is rare to see any mandatory requirements on electricity users anywhere in the world. Since 2018, Taiwan’s government has started to draft the RPS-TW to establish such obligation; but as a new mechanism, the greatest challenge lies in formulating feasible requirements that are apt to Taiwan’s circumstances. This study aimed to assist Taiwan’s government in this effort by formulating content that was feasible and meets external expectations regarding the applicable entities, scope, and methods of fulfillment. Once the draft had been revised accordingly, the public (electricity users, environmental groups, general public) were actively consulted, and the draft was modified and optimized based on widely collected feedback. The regulations were ultimately promulgated on 31 December 2020.

Wind farms in contested landscapes: Procedural and scale gaps of wind power facility constructions in Japan

The legal system for renewable energy in Japan, Feed-in Tariff system, was deregulated in 2021 by the central government to reflect the international calls to reduce greenhouse gas emissions. However, this sudden change has raised concerns about social, environmental, and long-term economic sustainability. Thus, we conducted a state-of-the-art review of legal and policy frameworks of wind power projects in Japan and discussed the multi-layered structure at national- and municipal-level ordinances. By doing so, several gaps are highlighted. First, there are procedural gaps that business operators can de facto bypass by checking the environmental procedures. Second, there are issues at the scale (national or local), where the decisions are met. For example, while the overall framework is decided at the national level, the most contentious issues of the location of wind power facilities are left at the local level, where residents, municipalities, and developers are burdened to solve these issues. Third, in the current legal system, environmental impacts on popular natural landscapes are not taken into consideration. In the face of deregulation and concerns about multiple factors, there has been an increase in the number of municipalities opposing the construction of wind farms. Finally, existing legal cases related to wind power projects are provided to illustrate changes and disputes at different sites across Japan. These cases demonstrated how landscape elements (e.g. biodiversity) can be vital for wind power project development in Japan.

Multi-microgrid optimization and energy management under boost voltage converter with Markov prediction chain and dynamic decision algorithm

Knowledge on operational energy consumption and embodied energy, replacing embodied greenhouse gas (GHG) emissions in building materials, and national energy resources have become a necessity. In this study, the importance of investigating the stochastic nature of weather-dependent renewable energies is well documented. The management of the hybrid renewable energy system (HRES) was built and assessed, utilizing a decision-making algorithm and 13 case studies. When the proportion of renewable energy is at 24% and the average daily fossil fuel usage is 1.11 L per year, the HRES generates 1697 kWh per year with a net present value (NPV) of 553,68 USD, with a rate of return (IRR) of 21.4%, and a payback period (PP) of 15.7 years. With a renewable energy share of 54%, fossil fuel consumption dropped to 0.69 L per year, while yearly energy output was comparable to 1652 kWh per year, with an IRR of 19.5% and a PP of 17.6 years. To achieve zero greenhouse gas emissions, HRES Management employs 100% renewable energy sources to generate 1933 kWh per year at a net present value of −372.09 USD. This scenario is economically possible if the renewable energy feed-in tariff exceeds 0.06 USD.

Market diffusion strategies for the PEM fuel cell-based micro-CHP systems in the residential sector: scenario analysis

At present, one of the most prominent support mechanisms for sustainable energy is implementing Feed-in Tariffs. This study analyzes Feed-in Tariffs for distributed electricity generation in Iran and Feed-in Tariffs for electricity generated by fuel cells in other countries. Based on reviews of the regulations and the support plans for renewable energy development, CHP generators, and fuel cells, four scenarios were designed for pricing the electricity generated from the fuel cells and how to support its market development. Based on these scenarios, the Feed-in Tariffs of electricity from fuel cells or the expected amount of support for each fuel cell unit was calculated. In the case of using a production tax credit (PTC) model, assuming the total export of the generated electricity to the grid, the cost per kilowatt-hour of electricity varied by 9.89–60.78 cent/kWh based on the utilization of different PEM fuel cell products of different companies. Using Iran's small-scale generator support guideline, the electricity generation cost was calculated between 7.032 and 57.921 cents/kWh.