Net Metering System Research Articles

Regulating Roof-Top Solar Generation: Defending Sustainable Projects from Utility Proposals

Residential owned solar panels mounted on roof-tops generated 1.4% of the U.S. electricity supply in 2022. Utilities compensate residential customers using a net metering system by which each kilowatt-hour generated by the customer reduces the customer’s bill by the amount the utility charges for one kilowatt. Despite the small impact of roof-top solar on the total market, in 2022, thirty-two states conducted ninety-four proceedings investigating whether to change the net metering system. In these proceedings, utilities advocated changing the rates to discourage residential investment in solar panels. Utilities argue that net metering provides a subsidy to solar customers because the rate the utility pays is greater than the avoided cost of energy. That excess payment allows solar customers to avoid paying for the distribution network. The cost of the distribution network is shifted to non-solar customers. This article will evaluate these claims. It will show that if the social cost of carbon were in the calculation, it would generate a Kapp cost shift from solar customers to non-solar customers. The size of the Kapp cost shift is greater than the cost of distribution networks, reversing any private cost shift that utilities have estimated.

Optimal household appliances scheduling for smart energy management considering inclining block rate tariff and net-metering system

Smart grids that integrate household renewable energy sources and share information with households can help create and maintain a smarter data-driven environment. Within this environment, flexible home energy management policies that minimize household energy costs can be adopted. This paper considers a smart home with a renewable energy source that favors satisfying its energy needs at minimum cost. This is achievable by smartly scheduling the use of its domestic appliances to match a given energy grid tariff. Focusing on the case of Egypt in which an inclining block rate (IBR) tariff is imposed, this paper fills a gap in the literature regarding the load scheduling models aiming to minimize energy cost at the household level whenever such a tariff exists. A new mixed integer quadratic programming (MIQP) model is formulated for this scheduling problem, considering the adopted net metering system with installed domestic photovoltaic (PV) systems in Egypt. The model generates the optimal household load schedule and the optimal amounts of energy to exchange with the grid while considering all the system and consumer utility constraints. To assess the applicability of the proposed model, a survey is conducted to identify the diversity and characteristics of using the electrical appliances by the Egyptian households. Based on the collected survey results, the effectiveness of the proposed MIQP model is investigated. Results confirm the effectiveness of the proposed model to minimize energy cost for different categories of the Egyptian households.

Detection of False-Reading in Smart Grid Net-Metering System

Malicious consumers may hack their smart meters (SMs) in the smart grid to report fake readings in order to make unlawful financial profits. Since the reported readings are used for energy management, the utility suffers significant financial losses as a result, and grid performance may suffer as a result. The net metering system, in which one SM is used to report the difference between the power consumed and the power generated, is the subject of this research, which is the first study to look into the issue. First, we process real power consumption and generation information to create a benign dataset for the net-metering system. The data was then examined, and time correlations between the net meter readings and correlations between the measurements and pertinent information from reliable sources, such as temperature, were discovered. Based on the data analysis, we suggest a single-pole double-throw detector to detect erroneous readings. In addition to data from reliable sources, our detector is trained on net meter readings from every customer in order to improve its performance by discovering correlations between them. We also create a relationship between the customer and the grid. Since the only billing system available nowadays is online, this project includes an app that may be used to solve a variety of problems, including electrical outages. Overall, with this, we improve customer and grid communication and simplify their lives.

Design and techno-economic evaluation of hybrid renewable energy system for an Upazilla Health Complex (UHC) in Bangladesh

Upazilla Health Complex (UHC) offers the primary level health care facilities for rural communities. Every day thousands of patients come here for health care. The Health complex needs 24 hours electric supply. The national Grid cannot provide continuous electricity supply. Rural areas face various disturbance such as load shedding, blackouts problems and bad weather situation. In this paper, we report on the techno-economic assessment of net metering based On-grid photovoltaic system for Kaunia Upazila Health Complex in Rangpur District, Bangladesh. The analysis is based on the grid-connected photovoltaic system without battery storage. The HOMER software is used to obtain the overall analysis and the load study is carried out by HOMER powering tools. It suggests that the selected health complex requires a 34 kW PV system. The system’s net present cost (NPC) and the levelized cost of energy (COE) are $35,524 and $0.048 respectively. In this proposed system, renewable energy provides 99% of the total power requirements, while the generator and grid provide only 1%. The system produces 53,736 kWh a year of electricity where the system’s surplus electricity is 3226 kWh per year which can be sold to the national grid using a net-metering system.

Analysis and hypothesis testing of redundant energy of solar home systems without net-metering

Solar home systems (SHS) are increasing being deployed as sustainable energy supply for the residential sector to meet the Sustainable Development Goal 7 target by 2030, especially for countries in sub-Saharan Africa (SSA) where national grid electricity supply is inadequate or weak. For SHS in SSA, however, a unique challenge exists as many of the households do not have access to net-metering system that allows extra PV energy generation during the daytime to be exported to the grid. This leads to waste energy generation (redundant energy) when the household energy demand is lower than the PV energy generation. In this study, analysis has been conducted to determine the magnitude of redundant energy of 3 SHS. Hypothesis testing of the existence of redundant energy from the SHS is also conducted. Our study has revealed that generally, there is redundant energy generation in the hours of 10 a.m. to 3 p.m. for the households, with hourly values ranging from 0.37 kWh to 1.55 kWh. The redundant energy represents 29.6 %–56.3 % of the households' monthly PV energy generation. The findings of this study give insights into the potential of harnessing redundant energy of SHS for planning smart energy cities if net-metering systems were available.

Predicting customers’ intentions to adopt the solar net metering system in India

PurposeThe study aims to investigate the factors influencing customers’ behavioral intentions to adopt solar net metering systems (NMS) through environmental consciousness, perceived consumer effectiveness and government initiatives constructs along with “the theory of planned behavior” (TPB) constructs, namely, attitude, perceived behavioral control, behavioral intentions and subjective norms.Design/methodology/approachThe data of 472 respondents were collected from 22 states of India using purposive sampling from January to May 2022. The study used international business machines corporation Statistical Package for Social Sciences software for descriptive analysis, and SmartPLS 3.5.5 software was used for structural equation modeling. The data were also checked for multicollinearity, common method bias, skewness and kurtosis using different tests.FindingsThe analysis revealed that environmental consciousness, perceived consumer effectiveness and government initiatives significantly influenced the attitude toward solar NMS. Furthermore, behavioral intentions were significantly impacted by three constructs of TPB, which signifies that environmentally conscious customers have a favorable attitude toward solar NMS adoption. Additionally, the role of government initiatives is essential in promoting solar NMS.Practical implicationsThis study offers valuable insights for the government, solar product manufacturing companies and other stakeholders to increase the adoption of solar NMS.Originality/valueThis research explores the factors influencing the consumers’ adoption behavior regarding solar NMS; no dedicated study has tried to do so in the Indian context in the past. This study adds novel underpinnings to TPB, enabling better comprehension of solar NMS adoption.

Factors Determining the Development of Prosumer Photovoltaic Installations in Poland

The development of energy production from renewable sources includes the production of energy from photovoltaic installations by prosumers. In Europe, RES development is driven by political goals and requires subsidies during the deployment period, at least as long as the cost of renewable electricity does not reaches grid parity. The study attempts to determine the importance of factors in the development of energy production by prosumers from PV installations in Polish regions. In 2019, the ‘Moj Prad’ program was introduced, applying subsidies to investment costs and the settlement of energy production in the net-metering system. Almost 900 thousand prosumer PV installations were built by the end of 2021, with a total capacity of 5.9 GW. Solar energy share grew from 0.1 to 2.1%. Spatial econometrics models were use in research to determine factors of prosumer PV systems development in Poland (at NUTS-2). Spatial regimes were found in the studied regions, as indicated by a positive autocorrelation (0.75). Considering the pseudo-R-square co-efficient, we can conclude that the spatial error, i.e., factors not included in the GNS model, constitutes approximately 10%. The economic variables included in the Mansky model, i.e., level of salaries and GDP, explain 90% of the variability of installed PV capacity (Nagelkerke pseudo-R-squared value is 0.906). The level of development of prosumer photovoltaic installations (in W per capita) in regions depends primarily on economic factors represented by the level of salaries in a given region. With the increase in salaries by one unit, we also have an increase in installed power capacity in watts per person by 3.52. Surprisingly, the region’s overall wealth did not matter, as the relative number of installations in regions with lower GDP was higher than in others. One can explain that the individual income of households is more important for increasing the number of prosumer installations than the income of the regional economy. The increase in the number of installations in one region contributed to the subsequent increase in their number in neighboring regions.

Modeling the Indian households' intention to adopt the solar net metering system

PurposeThe present study aims to develop and offer a model to evaluate the customers' attitude and intention to adopt solar net metering systems (commonly called solar NMS) in a developing economy. Therefore, the research examines different factors affecting the Indian households' attitudes and intention to adopt solar NMS.Design/methodology/approachThe data were collected from 247 solar NMS users from India. The structural equation modeling (SEM) technique was applied using SmartPLS 3.3.2 software to analyze the impact of various factors on their adoption intention. The conceptual model comprises environmental concern, perceived ease of use (PEOU), subjective norms, perceived usefulness (PU), attitude and behavioral intention to adopt solar NMS.FindingsSubjective norms and environmental concerns significantly influence the PU and PEOU of solar NMS. Also, PU and PEOU significantly influence their attitude and intentions toward adopting solar NMS. Thus, the perceived social pressure and environmental concern affect their perception of solar NMS's usefulness and ease of use, leading to favorable attitudes and adoption intentions. Additionally, the solar NMS benefits the customers, society and the environment by enhancing environmental quality, compatibility with the modern lifestyle, and reducing dependency on the power grid and electricity bills. These benefits shape the customers' overall perception and increase the adoption of solar technologies.Originality/valueThe present research helps bridge the gaps in the existing literature by identifying (1) factors affecting customers' intention toward solar technologies in developing nations and (2) describing the significant prediction of environmental concern and subjective norms to increase solar technologies adoption.

Solar energy development in households: ways to improve state policy in Ukraine and Latvia

ABSTRACT The paper investigates state policy to promote solar energy in Latvia’s and Ukraine’s households. Comparing different approaches to stimulating sectors’ development in both countries, the article evaluates the economic efficiency of solar power plants implementation based on the Levelized Cost of Electricity method and investment projects payback periods. The calculations were performed for solar power plants installed capacities ranging from 1 to 30 kW. The results revealed the fundamental differences in solar energy advancement due to the existing support mechanisms in the countries. While high feed-in tariff rates contribute to the rapid deployment of solar power plants in Ukraine’s, Latvia’s net-metering system hinders solar energy development in households. The research forms recommendations for improving policy by adjusting Ukrainian feed-in tariffs to trends in reducing solar energy costs, introducing solar energy in the Mandatory Procurement Component for Latvia, and applying preferential public financing to solar power plants construction in both states. Highlights State policy to promote solar energy in Ukraine’s and Latvia’s homes is analyzed The economic efficiency of small solar power plants is estimated for both countries Feed-in tariff in Ukraine ensures a quick payback period for solar power projects Net metering in Latvia does not provide investment attractiveness of solar plants Both countries need energy policy changes for balanced solar power development

Comparative analysis of solar - battery storage sizing in net metering and zero export systems

Solar energy is an intermittent as well as a variable resource. The integration of battery energy storage systems (BESS) with solar photovoltaic (PV) systems can help to mitigate some of the shortcomings of solar energy. In India, many states have a provision for net metering for solar projects. For states that do not allow net metering, a zero-export (grid export curtailed) system emerges as the preferred configuration. This paper presents a techno-commercial comparison of net metering and zero-export systems. An AC coupled grid-connected PV-BESS hybrid system is set up as our reference case so that the PV and battery components can be decoupled. Commercially available components used in actual installations have been selected to enable us to get realistic results. Financial metrics like levelized cost of energy (LCOE) and benefit cost ratio (BCR) are utilized to determine the viability of different system configurations. The optimum size of solar PV, as well as the capacity of BESS which can be integrated with solar PV, is derived, under net metering as well as zero-export regimes. For a 300 kW system, 51% of energy is curtailed in a zero-export system, as compared to a net metering system which has no curtailment.

Reducing Carbon Emissions from the Tourist Accommodation Sector on Non-Interconnected Islands: A Case Study of a Medium-Sized Hotel in Rhodes, Greece

Reducing the carbon emissions from hotels on non-interconnected islands (NII) is essential in the context of a low carbon future for the Mediterranean region. Maritime tourism is the major source of income for Greece and many other countries in the region, as well as hot-temperate and tropical regions worldwide. Like many NIIs, Rhodes attracts a high influx of tourists every summer, doubling the island’s energy demand and, given the high proportion of fossil fuels in the Rhodian energy supply, increasing carbon emissions. Using the theoretical framework ‘FINE’, this paper presents the optimisation of a medium-sized hotel’s energy system with the aim of reducing both cost and carbon emissions. By introducing a Photovoltaic (PV) net metering system, it was found that the carbon emissions associated with an NII hotel’s energy system could be reduced by 31% at an optimised cost. It is suggested that large-scale deployment of PV or alternative renewable energy sources (RES) in NII hotels could significantly reduce carbon emissions associated with the accommodation sector in Greece and help mitigate climate change.

Can photovoltaic systems be profitable in urban areas? Analysis of regulation scenarios for four cases in Valencia city (Spain)

Costs of photovoltaic systems have fallen over the last decade, while the energy prices have risen. As a result, PV system is being proposed as a cost-effective option for power generation in the built environment. However, some authors consider that better regulatory support is still needed to deploy the PV potential in cities. In this research, four illustrative cases, analyzed under five scenarios, show that the latter could be the case in a Mediterranean city with high annual solar radiation, such as Valencia. Unlike most previous research based on statistics, this research uses real data and real market equipment information to develop the analysis. The Software HOMER is used to simulate the performance of the study cases. The findings show how the regulation's change would improve the viability of these urban renewable systems. However, although the four cases are technically sound, further changes in the regulation are found necessary to be economically viable. The results show one of the main limitations to reducing the LCOE is the impossibility of selling energy when revenues are greater than purchases (Current regulation in Spain). Without such limitation, the LCOE would be reduced (cases 1 and 3 reduces LCOE from 17.5 to 15.2 c€/kWh and from 18.5 to 17.3 c€/kWh, respectively). With a net metering system not yet permitted in Spain, the payback of the investments would be reduced by one-third. Finally, recommendations for regulatory development are proposed to meet the expectations for the deployment of PV generation potential.

Detection of False-Reading Attacks in Smart Grid Net-Metering System

In the smart grid, malicious customers may compromise their smart meters (SMs) to report false readings to achieve financial gains illegally. This causes hefty financial losses to the utility and may degrade the grid performance because the reported readings are used for energy management. This article is the first work that investigates this problem in the net-metering system, in which one SM is used to report the difference between the power consumed and the power generated. First, we prepare a benign data set for the net-metering system by processing a real power consumption and generation data set. Then, we propose a new set of attacks tailored for the net-metering system to create a malicious data set. After that, we analyzed the data and found time correlations between the net meter readings and correlations between the readings and relevant data obtained from trustworthy sources, such as solar irradiance and temperature. Based on the data analysis, we propose a general multidata-source deep hybrid learning-based detector to identify the false-reading attacks. Our detector is trained on net meter readings of all customers besides data from trustworthy sources to enhance the detector performance by learning the correlations between them. The rationale here is that although an attacker can report false readings, he cannot manipulate the solar irradiance and temperature values because they are beyond his control. Extensive experiments have been conducted, and the results indicate that our detector can identify the false-reading attacks with a high detection rate of 98.59% and a low false alarm of 2.92%.

Network tariffs and the integration of prosumers: The case of Wallonia

In Wallonia, Belgium's southern region, the distribution component of the overall electricity retail tariff is essentially volumetric, i.e. based on the users' energy consumption (in €/kWh). Residential prosumers, moreover, are connected to the grid via a net-metering system. In this paper, we rely on a sophisticated multi-agent tariff simulator – developed in Manuel de Villena et al. (2019, 2020) – calibrated to this specific regional context to model the integration of prosumers into the distribution grid. This simulator enables us to highlight how the emergence of prosumers impacts the distribution network tariff, and to evaluate several tariff reforms currently under discussion: the introduction of a prosumer fee, the introduction of a capacity component and a switch to net-purchasing. Without a change in the metering system, short run reforms can only change the structure of the tariff paid, either to all consumers or to prosumers only. In the long run, especially thanks to smart meters, we consider both the introduction of a net-purchasing system and of a tariff with a capacity component. Our analysis highlights one key added value of smart meters: they allow network tariffs that are fairer and sustainable.

Optimum Sizing and Economic Assessment of Hybrid Microgrid for Domestic Load Under Various Scenario

Electricity price, various duties related to electricity bill and environmental concerns are increasing. Due to technological advancement and mass production, the price of solar modules and energy storage system are going down. Number of consumer are increasing having Solar Home System (SHS) so transform from consumer to prosumer. The aim to present assessment is to analyze the techno-economic feasibility of residential household at Karnal, India under three scenarios: grid connected net-metering system without feed in tariff, with feed-in-tariff and off-grid system so that the consumer can choose the best possible configuration as per their geographical location. The outcome of the study shows that grid connected system will require less investment and it will be more economical will feed-in tariff policy. Government support and environmental concern will help to motivate more peoples towards SHS so as to became less carbon free world.

Constitutional aspects of distributed generation policies for promoting Brazilian economic development

State regulation in the electricity sector is essential for economic development and serves as a foundation for sustainability in the modern world. Several incentives have been put in place to stimulate energy generation through renewable resources in Brazil, starting with Decree 5.163 from 2004 and Normative Resolution – REN no. 482 from ANEEL (National Electricity Regulatory Agency), which established ways for consumers to generate electricity for their own consumption using renewable sources, and to distribute this energy back to the grid via a net-metering system. This article addresses the issue of electric energy control, generation, and distribution, and gives new perspectives from within the Distributed Generation (DG) system. The main objective of this article is to analyze the incentive mechanisms for DG in Brazil from a constitutional standpoint, which were set forth to promote economic development in the Federal Constitution of 1988. Furthermore, this study discusses the regulatory nature of the State, and changes to its role in economic intervention, discussing economic development concepts for how regulation might impact the development and promotion of DG in Brazil.

Integrated system efficiency in reducing redundancy and promoting residential renewable energy in countries without net-metering: A case study of a SHS in Ghana

One of the key factors affecting progress of renewable energy (RE) in the residential sector in Africa is the unavailability of net-metering systems in many of its member-state countries. Huge battery storage would have to be put in place by individual households owning solar home systems (SHS) to store energy for early morning and night-time use, making the systems not cost-competitive. In this study, a new concept based on “integrated system efficiency (ISE)” has been developed to maximize direct use of electricity from SHS without net-metering. In a case study, real-time power consumption and solar PV electricity generation were monitored for an installed SHS in Ghana. The result showed that, in the absence of net-metering system, sustainable hybrid SHS can be realized if high consumption electrical loads comprising refrigeration systems, water pumping, and washing machines are shifted to daytime use, using ISE. The significant contribution of this study is that, for SHS without net-metering, a new performance parameter called “solar system redundancy factor” is identified as more appropriate indicator for measuring the actual usage of the PV electricity generation. Using the ISE concept developed in this study, the redundancy factor was minimized from 63.2% to 39.8% for the SHS.

PV adoption: the role of distribution tariffs under net metering

The deployment of decentralized productions units (DPU) like rooftop solar panels is a major challenge for a transition towards greener energy sources. Under a net metering system where the meter runs backward when there is excessive PV production, the electricity produced by a solar panel is valued at the retail price. Higher retail prices thus encourage the deployment of DPU. To identify this relationship, we use data from Wallonia where tariffs are paid on a mostly volumetric base and where there are 13 different tariff zones. Using various specifications, our results suggest that in a municipality where the distribution tariff is one eurocent per kWh higher, the investment in solar PV is, all else equal, around 8% higher.

Towards a smart grid power system in Brazil: Challenges and opportunities

The prospects for a smart power system have been widely discussed in the global electricity sector. Decarbonization, Digitalization and Decentralization are considered the main key drivers for this power system transition and Brazil is no exception to this universal trend. A search of the literature revealed few studies which attempt to address the main challenges and opportunities towards a smart grid power system in Brazil. This paper provides an up-to-date assessment of the present and potential capabilities of existing and future technologies, regulations and policies and attempts to identify how these elements are interrelated. Our findings add to a growing body of evidence suggesting that policies for Distributed Generation (DG), Demand-Side Management (DSM) and new tariff schemes are on a path of accelerated deployment in the country. The deployment of storage technologies, however, is at a slow pace of growth. We highlight the need to further develop new business models to address the various decentralized energy technologies and services that are emerging in the sector. The current net-metering system is considered a key issue to be addressed as this regulatory structure may shift the costs from DG to non-DG users.

Performance Analysis of Grid-Connected 10.6 kW (Commercial) Solar PV Power Generation System

In this paper design aspects and performance of a rooftop grid-connected solar photovoltaic power plant (RTGCSPVPP) has been studied. The RTGCSPVPP is installed at Gauri Maternity Home Ramkrishna Puram Kota Rajasthan, India for supplying the energy to whole hospital building. It was observed under a certain period of time during May 2017. Power output and other parameters such as economic parameters which affect the feasibility of a PV plant as payback period, net present value, life cycle conversion efficiency, environmental related parameters as CO2 mitigation and earned carbon credits were calculated. Total energy demand and monthly energy consumption of previous one year of the site was assessed and analyzed for base load calculation and design. The outcome shows the financial viability and possible reduction of burden on conventional energy sources. The grid-connectivity of PV plant made through a net-metering system which supplied energy to the grid when power generation is more than its demand and receives the energy during low power generation.