Net Metering Scheme Research Articles

Stochastic approach for economic viability of photovoltaic systems with battery storage for big electricity consumers in the regulated marketin Brazil

Today in Brazil, due to the government incentives, the Net-metering scheme can be seen as a Photovoltaic system that uses the power grid as a virtual battery. This analogy is possible due to the energy credits accumulated in the metering when the prosumer injects power to the network. When the government incentives run out, it can trigger an opportunity market to stimulate the consumers to have their own batteries. Associated with this, the Lithium-ion battery storage systems market has been promising due to a significant drop in battery prices in the last few years.This work proposes a stochastic mixed integer linear programming (MILP) model to design a photovoltaic system integrated with battery energy storage, using generation and consumption scenarios under a Time-of-Use tariff model applied in Brazil. The decision variables are the number of panels, inverters, batteries, its daily operation and the power demand contracted. The objective function aims to minimize the annual cost of investment in photovoltaic system and battery as well as in electricity bill in the context of the Brazilian rules.The proposed model was adapted for a scheme with free export to the network and other with zero export in order to assess the importance of a storage system to keep the economic attraction of the photovoltaic system. Results indicated that the synergic effect of the photovoltaic system and battery, potentialize the arbitrage, which is related to the difference between peak and off-peak energy tariff, mainly with Zero Export scheme because the consumer is free to choose the capacity of the photovoltaic system, which is limited for Net-metering scheme.

Net-Metering vs. Net-Billing from the Investors Perspective—Impacts of Changes in RES Financing in Poland on the Profitability of a Joint Photovoltaic Panels and Heat Pump System

The paper explores the impacts of changes in renewable energy sources (RES) financing in Poland on the profitability of coupled photovoltaic panels and heat pump systems. The profitability analysis is conducted with the use of Net Present Value calculation and the return on investment period. The degree of change in profitability of using photovoltaic panels in Poland is dependent on the method of their financing. The analysis is carried out for two different photovoltaic support schemes: (1) the net-metering scheme currently in force in Poland; (2) the net-billing system scheduled for implementation in the year 2022. It is assumed for the analysis that two alternative heating and electricity supply systems for a single-family building will be operated: (a) a standard solution used in Poland consisting of a natural gas-fired boiler for heating and the purchase of electricity from the power grid, (b) an air/water heat pump used to heat the building, and electricity obtained from photovoltaic panels, also used to power the heat pump. A sensitivity analysis is carried out, examining the impact of several key parameters relevant for the profitability of such investments, such as average annual increase in the purchasing or selling prices of electricity, purchasing prices of natural gas, and inflation rate. The conclusions concern the possible consequences of introducing a new support scheme for photovoltaics in Poland. The highest profitability of all considered solutions is for the current scenario for heat pump and pv installation with the capacity to meet the demand in the last year of operation. The introduction of changes in the new RES law (2021) in Poland will reduce the profitability of investments in pv panels, leading to a slowdown in the investments in the pv installations.

Optimal Sizing and Cost Minimization of Solar Photovoltaic Power System Considering Economical Perspectives and Net Metering Schemes

In this paper, economic feasibility of installing small-scale solar photovoltaic (PV) system is studied at the residential and commercial buildings from an end-user perspective. Based on given scenarios, the best sizing methodology of solar PV system installation has been proposed focusing primarily on the minimum payback period under given (rooftop) area for solar PV installation by the customer. The strategy is demonstrated with the help of a case study using real-time monthly load profile data of residential as well as commercial load/customers and current market price for solar PVs and inverters. In addition, sensitivity analysis has also been carried out to examine the effectiveness of net metering scheme for fairly high participation from end users. Since Saudi Arabia’s Electricity and Co-generation Regulatory Authority (ECRA) has recently approved and published the net metering scheme for small-scale solar PV systems allowing end users to generate and export energy surplus to the utility grid, the proposed scheme has become vital and its practical significance is justified with figures and graphs obtained through computer simulations.

PV roofs as the first step towards 100% RES electricity production for Mediterranean islands: The case of Cyprus

The challenge of integration of large scale RES to islands seems infeasible when the islands have isolated energy systems without primary fuel sources, with limited sources of RES and without energy storage systems. Cyprus island is one of these cases, which covers 93% of the energy demand using imported fossil fuels. Building sector is the second biggest energy consumer accounting for 19% of the final energy consumption. A net-metering scheme is introduced recently to promote the installation of small PV systems in buildings. This paper therefore takes the approach of analyzing various scenarios for installation of PV roof systems in existing and future households of Cyprus island until 2050. The goal is to achieve 100% renewable energy production to cover the needs of the households sector. Results show that the electricity demand of the domestic sector can be 100% covered when over 70% of the existing residential stock install 3 kW roof PV system. Even if 50% of the existing residential stock install a 3 kW PV system the required capacity from other applications (eg. PV parks) to make domestic sector 100% renewable is 191 MW, which is feasible. To ensure a smooth transition to 100% renewable energy in all sectors, significant actions should be taken for the development of renewable energy systems, sector coupling, smart grid system planning and storage technologies. The present study examines only the potential of the further use of net-metering scheme in the domestic sector and discusses the barriers to full energy transition as well.

Grid parity analysis of distributed PV generation considering tariff policies in Argentina

This work analyzes the grid parity of distributed photovoltaic generation (DG-PV) in the province of San Juan-Argentina, proving that currently, the levelized cost of DG-PV is on average 20% higher than the tariff price for residential customers. In order to achieve the grid parity, the provincial government should implement incentive mechanisms such as the Net Billing proposed in the National Law 27.424 (2017). The impact of the Net Billing scheme proposed in such law, from the point of view of a typical residential user, and also compared with the impact of the Net Metering and Feed-in Tariff mechanisms are presented in this work. Results show that the Net Metering scheme could be the most profitable or economically beneficial for PV-owners, but it could have some negative impact on the incomes of utilities. Besides, investment decisions in renewable distributed generation are significantly affected by technological costs, national financial conditions, and tariffs. This analysis also suggests that taxes included in the tariff structure are an important aspect to take into account for implementing incentive mechanisms. Finally, some energy policies are recommended to guarantee the profitability of DG-PV systems and to assist the government in making decisions to promote these systems.

Energy storage sizing and enhanced dispatch strategy with temperature and safety considerations: A techno‐economic analysis

AbstractMalaysia signed Paris agreement in 2015 as global response to climate change and committed to lower the greenhouse gases emissions by 45% by 2030. Under this national initiative, Malaysia government planned a series of large scale solar (LSS) projects and regulated by Energy Commission. It is aimed to achieve installed capacity of 1 GW by 2020. One of the main drawbacks for using solar energy is the intermittent issue in solar power generation. This will affect the power quality and reliability of the power grid especially in the LSS systems. This article aims to identify and optimize the most technically and economically viable energy storage system (ESS) for selected locations among the ongoing mega projects. The location selection for this study is based on the largest solar capacity planned for Peninsular Malaysia. This project involved development of hybrid scheme including Flywheel and nine different types of battery at six locations in Malaysia using Energy Commission Malaysia's data. Comprehensive power systems have been developed with different storage options applied to selected locations. This is followed by extensive techno‐economic evaluation using net present cost, levelized cost of electricity including costs of ESS, operation & maintenance, initial capital investment, replacement cost, revenue from ESS, annual throughput, and so on. Comparative studies under two different dispatch strategies with local contextualized data for LSS projects in Malaysia have been carried out. The optimal ESS type both technical and economically has been identified. In addition to this, performance of battery ESS with and without temperature consideration has been evaluated. Last, data from a net metering scheme is used to analyze the ESS types that exhibit best performance. Safety concerns related to these ESS types have been provided. Last, this article also presents the adaptability and replicability of the proposed methodology in countries that planned for LSS with local contextualized data.

Assessing the influence of legal constraints on the integration of renewable energy technologies in polygeneration systems for buildings

Hybrid polygeneration systems offer a great opportunity to meet growing energy demands with cost efficiency and environmental benefits. The identification of the optimal solution (configuration and operational strategy) is strongly affected by the relationship between the system and its surroundings. Previous studies have analyzed the influence of boundary conditions on the synthesis of polygeneration systems for buildings. However, local regulations are often disregarded or oversimplified in those studies. Therefore, this paper aims to evaluate the influence of legal conditions on the integration of renewable energy technologies in polygeneration systems for buildings. A comprehensive synthesis model is developed, including different types of legal conditions, such as power exchange modalities, subsidies/surcharges on energy prices and investment costs, and total ban on fossil fuels. Then, the model is applied to the case study of a Brazilian hospital. The current Brazilian net metering scheme is implemented. Results show that natural gas cogeneration is an attractive solution to cover the hospital's energy demands with or without the possibility of selling/exporting electricity. Also, the Brazilian net metering scheme, by itself, is not enough to ensure renewable energy deployment. An in-depth discussion about the conditions that would promote renewable energy integration is reported and recommendations are made on how current policies can be improved, including the need to explicitly address renewable technologies, the application of minimum renewable fractions, and the role of renewable heat/cooling. While the case study considers the specific circumstances in Brazil, it provides insights that can be extended to other countries or applications.

Feasibility of Small Wind Turbine via Net Metering in Greek Islands

The evaluation of a small 3kW wind turbine through the net metering scheme is studied in this article. 14 near to sea locations in Greece examined with the help of the RetScreen expert software. The simulations based on electrical, financial and environmental criteria. Siros with average wind speed of 6.93 m/s is the most attractive area while Iraklion is the least attractive location. According to the results the simulated project is already economically sound and a small wind turbine in the Greek islands will become a progressively an even more financially source of electricity in Greece. Finally yet importantly is the fact that the use of small wind turbines has as a result that significant amount of Greenhouse gases do not reradiate into the topical atmosphere.

A two‐stage multi microgrids p2p energy trading with motivational game‐theory: A case study in malaysia

Peer-to-peer (P2P) energy trading is expected to be emerged as a new energy management paradigm that allows the transaction of energy from one prosumer to another prosumer without any dependency on a central controller. In Malaysia, first pilot test of P2P trading has been conducted recently, which exclusively participated by industrial prosumers and commercial consumers only. In order to investigate the impact of P2P energy trading to Malaysia market, this paper proposes an auction-based two-stage P2P trading market-clearing strategy, for multi-cities and intra-city in Malaysia. A motivational game theory-based price scheme is presented to ensure an unbiased market operation, to maximize the saving and payoff for each prosumer, at the same time benefits the power utility company. The proposed two-stage market clearing model is solved by Linear Programming optimization approach. A realistic representation of P2P trading in Malaysia is constructed and tested out under multi-cities and intra-city energy trading test cases. Comparison between the proposed P2P energy trading with existing solar generation net metering scheme is also presented. The numerical results indicate the viability and potential of motivational game theory based P2P trading in future Malaysia transactive energy market.

Analysis of the Net Metering Schemes for PV Self-Consumption in Denmark

The current Danish regulatory framework BEK 999/2016 for hourly net settled new PV facilities is analysed in detail, evaluating the technical and economic differences between the several envisioned schemes. In addition to the saved cost of the self-consumed energy, the transmission system operator (TSO) tariffs and the public service obligation (PSO) tax are avoided for the self-consumed energy. Advantages regarding the electricity tax and VAT can also be obtained but according to a more varied casuistry, with a particular incentivizing effect for the residential customers. The installation-connected type group 2 is found the cheaper scheme and the billing concepts responsible for its minor cost are identified. This analysis is expected to contribute to discerning the different economic outcomes of the various schemes, helping to take informed investment decisions. Transcending the local value, some common characteristics of this complex framework that can also be found in other regulations may ease the comprehension of the leverage points and the policy instruments for modulating the economic results of the facilities and in this way also their path of deployment.

Distributed energy cost recovery for a fragile utility: The case of Électricité du Liban

Previous research on distributed solar PV (DPV) systems in Lebanon has focused on studying these systems from the perspective of developers. This study examines the impact of DPV expansion from the perspective of a fragile and inefficient power utility, Électricité du Liban. Specifically, this paper studies the economics and policy options of on-grid systems via a net-metering scheme. The analysis yields two primary recommendations: In the absence of tariff reform for cost recovery, DPV policies should promote self-consumption; and after cost recovery is achieved, DPV tariff should ensure an adequate price differential that balances the interests of EDL and prosumers.

Possibilities of Transition from Centralized Energy Systems to Distributed Energy Sources in Large Polish Cities

The main aim of this paper is to evaluate the possible transition routes from the existing centralized energy systems in Polish cities to modern low-emission distributed energy systems based on locally available energy sources, mainly solar energy. To evaluate these possibilities, this paper first presents the current structure of energy grids and heating networks in Polish cities. A basic review of energy consumption in the building sector is given, with emphasis on residential buildings. This paper deals with the evaluation of the effectiveness of operation of central district heating systems and heat distribution systems; predicts the improvement in the effectiveness of the energy production, distribution, and use; and analyzes the possible integration of the existing system with distributed energy sources. The possibility of the introduction of photovoltaic (PV) systems to reduce energy consumption by residential buildings in a big city (Warsaw) is analyzed. It is assumed that some residential buildings, selected because of their good solar insolation conditions, can be equipped with new PV installations. Electricity produced by the PV systems can be used on site and/or transferred to the grid. PV energy can be used not only for lighting and electrical appliances in homes but also to drive micro- and small-scale heat pumps. It is assumed that the PV modules are located on roofs of residential buildings and are treated as individual micro scale energy systems of installed capacity not larger than 50 kW for each of the buildings. In such a case, the micro energy system can use the grid as a virtual electricity store of 70% or 80% efficiency and can produce and transfer electricity using a net-metering scheme. The results show that the application of micro-scale PV systems would help residential buildings to be more energy efficient, reduce energy consumption based on fossil fuels significantly, and even if the grid cannot be used as a virtual electricity store then the direct self-consumption of buildings can reduce their energy consumption by 30% on average. Development of micro-scale PV systems seems to be one of the most efficient options for a quick transformation of the centralized energy system in large Polish cities to a distributed energy one based on individual renewable energy sources.

Aerodynamic modeling of simplified wind turbine rotors targeting small-scale applications in Sri Lanka

A design and optimization procedure of simplified wind turbine rotors for small-scale applications is presented. The need for this research has arisen from the recent national initiative of the government of Sri Lanka titled ‘Battle for Wind Energy’ in promoting small scale grid connected wind plants for electricity customers under Net Metering scheme. The main objective of this research is to assist local developers to design optimum rotors for given electrical generators (as determined by customer requirements), suitable for wind characteristics at specific locations. Another objective is to enhance local manufacturing capabilities by providing a design option of a simplified rotor blade geometry. A study on the correlation between population density of electricity customers and wind energy potentials was carried out to categorize the demand centres based on wind energy potentials in proposing series of small-scale wind turbine designs. A unique and improved rotor design procedure is presented which attempts to match the point of maximum performance of a rotor (design tip speed ratio) with the design wind speed of a given location by considering generator performance. The new design procedure showed successful convergence on a unique blade diameter for each rotor configuration that allowed the design tip speed ratio to match the design wind speed. The performance evaluation of rotor designs showed that high solidity rotors work better on the low wind potential region while low solidity rotors dominate medium and high wind potential regions. The performance reductions of simplified rotor designs are not significant and therefore would be an effective way to enhance value addition through local manufacture. Problem statement•Lack of a rotor design procedure that considers generator performance.•Lack of a rotor design procedure for blades with an optimum simplified geometry.•Geographical mismatch between high resource sites and location of electricity consumers in Sri Lanka.•Lack of optimized small-scale wind turbine designs for sites with different wind potentials in Sri Lanka.•Limited opportunities for local manufacture in Sri Lanka. Major novel contributions•Identification of geographical locations most suitable for promoting small-scale wind turbines.•Creation of rotor design procedures for optimized and simplified blade geometries considering generator performance.•Creation of optimized and simplified wind turbine rotor designs for different wind potential regions in Sri Lanka.

Editorial: Governing the EU's climate and energy transition through the 2030 Framework

Editorial: Governing the EU's climate and energy transition through the 2030 Framework

The EU’s 2030 Climate and Energy Policy Framework: How net metering slips through its net

AbstractNet metering is a support scheme for the promotion of renewable energy sources (RES) that is linked with state‐of‐the‐art trends, especially in the field of electricity, such as distributed generation, self‐consumption and energy communities. Whilst the European Union (EU) Clean Energy Package has established a more coherent and comprehensive regime for RES support schemes in general, it makes no explicit reference to net metering schemes. This raises questions as to how and under which terms net metering schemes are compatible with EU law. Against this background, this article aims to analyse the relevant EU law provisions and conduct a comparative analysis of net metering regimes in four Member States to demonstrate that the national schemes enacted and applied have significantly different design features. The article argues that a more coordinated and specific approach on net metering at the EU level should emerge.

Danish PV Prosumers’ Time-Shifting of Energy-Consuming Everyday Practices

Consumer engagement in the energy system is necessary to ensure a low-carbon transition. However, this has proved difficult because consumers are engaged in pursuing everyday practices rather than focusing on abstract questions of energy. Recent studies have suggested that being a prosumer can make a difference. This paper builds on survey data from a representative sample of 2505 photovoltaic (PV) owners in Denmark combined with 12 qualitative in-depth interviews. The results indicate that PV owners consider that they have become more concerned about energy consumption and adjust the timing of their everyday practices to their production. Thus, 67% of the households ‘often’ or ‘always’ time-shift the use of washing machines to their production. The extent to which households time-shift is strongly related to their net-metering scheme. Thus, 75% of the households on hourly metering stated that they ‘to some’ or to ‘a great extent’ adjust their consumption, compared to only 26% of the households on annual metering. This financial effect is interpreted in an everyday life context where financial gain transfers meanings of self-sufficiency and sustainability, rather than primarily being viewed as rational economic behaviour. The conclusion discusses the policy implications of methods to engage the consumer.

Feasibility Study of Installing Rooftop PV System with Net-Metering Scheme in Iraq

Renewable energy, particularly solar energy, offers a clean and alternative energy source to meet the energy demand for sustainable development in the world. Due to its profitability and viability, PV net-metering scheme has been adopted in many countries. The feasibility of implementation PV rooftop system with net metering in residential, commercial, governmental and industrial sectors in Iraq is demonstrated in this study. A financial model has been developed to investigate the feasibility parameters NPV, IRR and annual savings of 24 kWp PV system. The results showed that increasing the capacity of the PV system in residential and commercial buildings will lead to a profitable investment return and the breakeven point that may make the PV net-metering projects feasible is very close to the tariff applied for the commercial sector (10.29 $c/kWh). In the governmental sector, the tariff needs to increase by 35.1% to reach breakeven. However, for such net-metering scheme to be attractive and feasible on a wide scale, it is crucial to back it with financial support through soft loans and grants.

Profitability assessment of PV rooftop implementation for prosumer under net metering scheme in Indonesia

Profitability assessment of PV rooftop implementation for prosumer under net metering scheme in Indonesia

An agent-based model to simulate technology adoption quantifying behavioural uncertainty of consumers

A good estimation of consumers’ expected response to specific policy measures is of paramount importance in the design of effective schemes for the adoption of new technologies. The decision-making process of consumers is influenced by a multitude of factors. In this context, agent-based modeling techniques provide an appropriate framework to model such private adoption decisions. However, the models currently in use often fail to capture uncertainties related to agency and their ability to replicate reality. In order to address this drawback, we developed an agent-based technology adoption model that is supported by a complete framework for parameter estimation and uncertainty quantification based on historical data and observations. The novelty of our model lies in obtaining realistic uncertainty bounds and splitting the total model output uncertainty in its major contributing uncertainty sources. In this article, we demonstrated its applicability by exploring the evolution of the market share of small-scale PV systems in Greece, under two support schemes of interest. Our results indicated that, over 2018–2025, the net-metering scheme, currently operational, seems more effective than a proposed self-consumption scheme that subsidizes residential storage by 25%; however, the former scheme’s effectiveness is mainly related to the retail price of electricity. They also highlighted that storage investment costs need to follow a steep learning curve of at least a 10% annual reduction until 2025, for self-consumption to become attractive to consumers in Greece. Nevertheless, simulations showed that none of these two schemes can be as efficient as the previous feed-in-tariffs scheme.

Single-dwelling and community renewable microgrids: Optimal sizing and energy management for new business models

Grid-connected microgrids (MG) can offer significant benefits to electricity systems by improving the security of energy supply with clean renewable energy sources. Unlocking these benefits requires designing suitable business models that can capture the value of MGs and that help removing barriers to their uptake. In this work, we evaluate the profitability and self-sufficiency of optimally designed MGs for new proposed business models. The business models are tested in seventeen different geographical locations which offer a vast diversity of renewable resources, seasonal climatic variability and electricity tariffs. Both Net Billing and Net Metering schemes are tested, for both single-dwelling and community residential customers. Electricity tariffs include both energy volumetric and peak demand charges. We model the optimal sizing and energy management of the MGs by minimizing the total customer electricity costs. The generation mix of the MGs is the result of a bilevel optimization which take into account renewable resources and costs, diesel prices and tariffs. MGs can potentially be comprised by solar PV, wind and diesel generation, together with battery storage systems and demand response resources. We find significant levels of self-sufficiency based on solar sources across the country, and also wind power in some specific locations. The community business model, case which includes the peak demand charges, is generally more profitable than the case of single-dwellings. This shows that the MGs are effective at reducing the peak demand charge of a residential electricity bill. We therefore recommend the further promotion of community energy arrangements as a key way to improve the current very slow uptake of distributed generation in developing countries.