Residential Rooftop Photovoltaic Research Articles

An avenue for providing the integration of distributed PV generation in low-income dwellings in Brazil

The purpose of this study is to analyze the impact on the income of families benefiting from the “Minha Casa Minha Vida” Brazilian Social Housing Program through the integration of photovoltaic (PV) generation systems into housing financing, as outlined by Law 14,620 enacted in July 2023. Given the novelty of this legislation, there is no existing database for analysis. Consequently, simulations of PV generation were carried out for the typical dwellings provided by the program across the five macro regions of Brazil. The simulation takes into account maintenance and equipment replacement costs, tariff rules, and standard adjustment rates in the country. Across all examined scenarios, the installation of residential rooftop PV systems yielded favorable outcomes, resulting in a reduction in electricity costs for the low-income population. Making provisions for a Sinking Fund in the program was identified as crucial to provide sustainability, long-term operation, maintenance and replacement. Additionally, it was observed that civil construction companies play a crucial role in popularizing the proposal. In conclusion, legislation incorporating PV generation into the national housing program represents merely the initial step toward realizing the widespread adoption of this energy generation technology in the country.

A System Dynamics Model for Rooftop Solar PV System Development in Indonesia

Despite of Indonesia’s vast solar energy potential according to the Indonesian Ministry of Energy and Mineral Resources, Indonesia’s total installed capacity of rooftop solar photovoltaic (PV) is very far from Indonesia’s target of 3.6 GW in 2025. Indonesia once applied net metering scheme for rooftop solar PV policy and was expected to be able to boost rooftop solar PV growth. A system dynamics approach is used in the research to develop an assessment model to evaluate the policies’ impact on residential rooftop solar PV system growth. A Causal Loop Diagram was established then transformed into Stock and Flow Diagram (SFD) using software Vensim PLE 10.1.3, which was used to simulate several policies’ scenarios related to residential rooftop solar PV adoption and CO2 emissions reduction. Ten scenarios were simulated in this study involving three groups of intervention: initial net metering tariff, reduction on initial solar PV cost, upper limit of ROI, and combination of initial net metering tariff and initial solar PV cost reduction. The simulations revealed that combination of increasing net metering tariff to 80% & initial cost reduction 30% has the highest potential solar PV installations, the highest CO2 emissions reduction, and the lowest accumulation cost of net metering in 2030. This study can be used as reference by the policy makers in Indonesia to formulate the optimum policy to boost rooftop solar PV growth as the simulations shows that residential rooftop solar PV with the right intervention can meet the government’s target of rooftop solar PV in 2030.

Not All about the Money: The Role of Financial Information in Promoting Residential Rooftop Photovoltaics

This study investigates the role of financial information in shaping the intention to adopt (ITA) Residential Rooftop Photovoltaic (RPV) systems in Israel—a country with a surprisingly low RPV adoption rate given the high solar irradiance, and significant governmental support for RPV. We used an online survey of 899 respondents to examine how different presentations of RPV revenues impact both RPV deal comprehension and ITA. Our results align with existing literature on the roles of early technology adopters and pro-environmental characteristics while introducing two novel findings. First, households value their roofs—especially flat ones used for leisure. This negatively impacts ITA. Second, we found a positive correlation between trust in government entities and ITA, underscoring the importance of trust in institutions. Although financial information does enhance RPV deal comprehension, it does not significantly influence ITA. This study concludes that RPV penetration should not be promoted solely by financial incentives, but also by other motivations like environmental concerns, novelty seeking, and improved institutional trust.

PV Identifier: Extraction of small-scale distributed photovoltaics in complex environments from high spatial resolution remote sensing images

The precise location and size of distributed photovoltaics (PVs) is critical to infer the actual installed capacity and assess the remaining PV generation potential, and is therefore the cornerstone of strategic planning for distributed PV deployment. However, identifying small-scale distributed PVs in complex contexts from high spatial resolution remote sensing (HSRRS) images to obtain their information remains an issue. In this study, we propose an advanced deep learning model, called PV Identifier, to enhance the identification accuracy of small-scale PV systems from HSRRS images. PV Identifier uses a fine-grained feature layer (FFL) compatible with the size of PVs to improve the detection capability of the small-scale distributed PVs. At the same time, it effectively distinguishes between PVs and similar background using a novel semantic constraint module (SCM). We test PV Identifier on a distributed PV dataset in California. Experiments show that the inclusion of the FFL positively affects the model's sensitivity to small distributed PVs. Specifically, the PV Identifier with the FFL increases the Recall of identifying residential rooftop PVs by 1.9% compared to the model without the FFL. In addition, the integration of the SCM effectively improves the model's ability to locate residential rooftop PVs in complex environments, resulting in a 1.8% increase in the corresponding Precision. Compared to the four commonly used segmentation models, PV Identifier exhibits superior identification performance for residential rooftop PVs and commercial and industrial PVs, with an Intersection over Union (IoU) of 74.1% and 89.3%, respectively, which is at least 4.1% and 1.8% higher than other models. Overall, PV Identifier provides a viable solution to the problem of identifying small-scale distributed PV in complex backgrounds from HSRRS images.

Stakeholders' awareness of urban form effects on rooftop solar photovoltaic in Ghana: Implications for integrated solar energy and urban planning

Integrating solar energy considerations into urban planning practices, a socio-technical and multi-stakeholder approach known as solar urban planning, is essential for maximizing solar photovoltaic (PV) potential in the built environment. While the need for such an approach is articulated in solar energy studies and urban planning, very few research explore the extent to which key stakeholders critical to this process are aware of the connections between urban form and rooftop solar PV and its implication for solar urban planning. This study examines stakeholders' awareness of the effects of selected urban form attributes on residential rooftop solar PV and its implications for solar urban planning in Ghana. Primary data were collected using surveys and interviews of households, real estate developers, licensed solar home system (SHS) installation companies, and government agencies responsible for energy and urban planning. SHS installation companies affirmed that buildings' roof type and shape, roofing material, the height of neighboring buildings, and the trees' position significantly affect rooftop solar PV installation and performance in Ghana. However, households have a low awareness of how these urban form attributes affect rooftop solar PV. Despite the affirmed effects of urban form on rooftop PV, current planning legislations do not necessitate considering such systems in preparing urban and building plans. A robust institutional collaboration is necessary among urban planning authorities, energy regulators, and real estate developers to develop effective strategies for solar urban planning in Ghana.

Real options valuation of photovoltaic investments: A case from Turkey

Investments in renewable energy resources have become inevitable due to increasing energy demand and energy prices, diminishing non-renewable energy resources, and the outgrowth of carbon footprints. Photovoltaic (PV) systems offer high solar energy potential in sustainable energy production whereas their high initial costs necessitate critical strategic valuation of investments. Valuation with conventional methods has been challenging due to existence of uncertainties such as fluctuating PV panel prices, changing meteorological conditions with certain effects on power generation, and governmental policies on energy market regulations. This study aims to propose a real options approach to valuation of residential rooftop PV system investments considering these uncertainties and demonstrate benefits of this approach with an application on the residential PV investment decisions in Turkey. The proposed method, Real Options Valuation (ROV) with Least-Squares Monte Carlo Simulation (LSMC) considers the deferral option of the investor by utilizing stochastic simulations, the discounted cash flow method, linear regression, and backward dynamic programming and thus evaluates the effects of uncertainties on financial attractiveness of residential PV investments. The case study findings proved that ROV with LSMC having a 7-years deferral option supported the investment decision with realizable cost-effective options while “NPV method” resulted in an infeasible investment. Scenario analysis was also conducted to explore policy options that can be used to promote solar energy investments in Turkey. This study has a potential to have practical contributions for investors as well as implications for policy-makers.

Techno-economic analysis of residential rooftop photovoltaics in Spain

In response to the European Commission's renewable energy targets for 2030, this study presents a comprehensive, data-driven evaluation of the potential for electricity self-consumption in the Spanish residential sector based on rooftop PV systems. Utilizing real-time hourly electricity demand data and various surplus compensation policies, the research highlights the significance of data granularity, indicating that annual data-based PV estimations can lead to rooftop PV self-consumption capacity overestimations when compared to hourly data assessments. Furthermore, geographical variations reveal distinct rooftop PV self-consumption capacities between urban and rural areas, driven mainly by the prevalent building typologies. This discrepancy suggests that while rural regions, with their predominance of single-family dwellings, offer higher PV generation potential due to more available rooftop space, urban areas, dominated by multi-story buildings, face significant constraints in rooftop surface availability. Economically, the current surplus compensation policy in Spain reduces the profitability of PV installations, underscoring the necessity for enhanced policies to fully utilize all the available rooftop areas in the residential sector. The study's findings, particularly the revelation that residential rooftops in Spain may not be enough to meet the current electricity demand, emphasize the need for adaptive, region-specific policies and the potential role of energy communities. Policymakers and industry stakeholders are urged to prioritize rooftop utilization, ensuring the deployment of PV systems is both promoted and economically viable, steering Spain closer to its renewable energy and sustainability aspirations.

Consumption and production of cleaner energy by prosumers

As investments in small-scale energy generating systems, such as residential rooftop photovoltaics (PV), increase it is not clear how electricity generated from these systems affects energy consumption decisions such as the purchase of green electricity offered by electric utilities. We present two utility-maximization models to determine energy consumption and production decisions and conduct simulations to test the strength of relationships. The first model maximizes a prosumer’s utility function where the size of PV is exogenous. The second model presents a prosumer that makes decisions in two stages — utility maximization to determine energy consumption and net revenue maximization to determine size of the generation system. Results from the exogenous model suggest that while there is a positive correlation between PV system size and total energy consumption, the impact on green electricity purchases (non-negative) is very weak. When the prosumer optimally chooses her system size, the optimal size increases with electricity prices. These results have implications for achieving decarbonization goals through an energy transition.

A Novel Topology for DC Electric Spring With Parallel Structure

Direct current electric spring (DCES), as a new solution for the power quality issue caused by the unstable output of photovoltaic (PV) and wind power integrated into the DC microgrid, has the advantages of flexible configuration, smart and small size. This paper proposes an improved topology based on the recent proposed DCES with parallel structure, defined as DCES-3, for residential rooftop PV power generation, and proposes a control strategy based on the small-signal modeling. The proposed topology consists of a triple active bridge (TAB) and a Buck-Boost converter (BBC), and adopts the overall control scheme of three-dimensional decoupling based on single phase-shifting (SPS) control, and uses the BBC to connect the non-critical load (NCL) in parallel to form an equivalent variable load. The DCES passes the power fluctuations to this variable load by changing the duty cycle of the BBC, while ensuring the power on the CL stable. Compared with DCES-3, it has the advantages of clearer concept of ‘spring’, easier analysis of transmission power and zero-voltage switching condition, controllable power quality of the NCL, lower scene transformation and production costs. Finally, the correctness and effectiveness of the proposed DCES topology and its control have been validated by both simulation and experimental results.

Residential Rooftop Photovoltaic Adoption Using a Sequential Mixed Methods Approach in Qatar

Global warming and climate degradation are critical global issues that influenced the rise of renewable energy sources adoption. Photovoltaic systems are the predominant sustainable and renewable energy source option, which can be deployed on top of residential rooftops on a large scale. However, the success of residential rooftop photovoltaic system adoption depends on multiple barriers, such as public acceptance and perception, market readiness, and supportive governmental policies. While most studies focus on either the customer perception or the market penetration aspects, this study aims to use a combinational approach. Through a mixed method approach, the goals of this study are to: (1) Complete a quantitative analysis on customer acceptance and perception of rooftop photovoltaic systems; (2) Perform a qualitative analysis on the potential of residential rooftop photovoltaic market penetration and the extent of supportive governmental policies; (3) Utilize the mix method approach results to answer adoption hypothesis. A few countries already have strong residential rooftop photovoltaic applications; however, many countries are still at an early stage of photovoltaic system adoption, where this study can be useful. This research uses Qatar as a prime case study in developing the study framework.

Grid Parity of Residential Building Rooftop Solar PV in India

Rooftop solar photovoltaic(PV) installation in India have increased in lastdecade because of the flat 40 percent subsidy extended for rooftop solarPV systems (3 kWp and below) by the Indian government under the solarrooftop scheme. From the residential building owner’s perspective, solar PVis competitive when it can produce electricity at a cost less than or equalgrid electricity price, a condition referred as “grid parity”. For assessing gridparity of 3 kWp and 2 kWp residential solar PV system, 15 states capitaland 19 major cities were considered for the RET screen simulation by usingsolar isolation, utility grid tariff, system cost and other economic parameters.3 kWp and 2 kWp rooftop solar PV with and without subsidy scenarioswere considered for simulation using RETscreen software. We estimate thatwithout subsidy no state could achieve grid parity for 2kWp rooftop solarPV plant. However with 3 kWp rooftop solar PV plant only 5 states couldachieve grid parity without subsidy and with government subsidy number ofstates increased to 7, yet wide spread parity for residential rooftop solar PV isstill not achieved. We find that high installation costs, subsidized utility grid supply to low energy consumer and financing rates are major barriers to gridparity

Simulating the Diffusion of Residential Rooftop Photovoltaic, Battery Storage Systems and Electric Cars in Italy. An Exploratory Study Combining a Discrete Choice and Agent-Based Modelling Approach

Rooftop solar photovoltaic (PV) systems could significantly contribute to renewable energy production and reduce domestic energy costs. In Italy, as in other countries, the current incentives generate a modest annual increase after the generous fiscal incentives that kick-started the PV market in the 2008–2013 period. Several factors are, however, at play that can speed up the installation process, such as the improvements in PV technology at declining prices, the increased availability of battery-storage (BS) systems, the growing use of electric appliances, the uptake of electric cars, and the increased environmental awareness. We integrate two research methodologies, discrete choice modeling and agent-based modeling, to understand how these factors will influence households’ decisions regarding PV and BS installations and how agents interact in their socioeconomic environment. We predict that in Italy, given the preference structure of homeowners, the continuing decline in costs, and the social interaction, 40–45% of homeowners will have PV or PV and BS installed by 2030, thanks to the existing investment tax credit policy.

Community Battery Storage Systems Planning for Voltage Regulation in Low Voltage Distribution Systems

The regulation of the grid voltage within operational limits becomes increasingly challenging as residential photovoltaic (PV) adoption rises. Therefore, this study proposes a method for the efficient planning of multiple community battery energy storage systems (BESS) in low voltage distribution systems embedded with high residential rooftop PV units. A bi-level optimization method based on a Neural Network Optimization Algorithm is developed to regulate the voltage in grid-connected solar PV. Since BESS characteristics are crucial for the reliable operation of the distribution networks, the objective of the bi-level optimization problem is to optimally place and operate BESS collectively at a distributed system level. The charging/discharging protocol of the batteries management system is obtained utilizing linear programming that minimizes the daily voltage signal. Simulations were carried out on a modified IEEE low voltage test feeder to examine the impact of PV integration and BESS installation on the voltage profile. Experimental results show the efficacy of the proposed method in enabling the utility to determine the optimal location, capacity, and number of BESS in the distribution system to keep the network voltage magnitude within acceptable bounds. In addition, results demonstrate that the network topology, load profiles, and amount of PV power highly influence the BESS characteristics.

Determining the influencing factors in the residential rooftop solar photovoltaic systems adoption: Evidence from a survey in Qatar

Renewable energy sources have developed rapidly, decreased in cost, and proven to have the potential to limit global warming. Renewable energy in the form of solar energy can be collected through decentralized rooftop solar systems. Solar energy development in Qatar is still at an early stage. The abundance of solar radiation, high GDP, and plentiful access to rooftop spaces make rooftop photovoltaic (PV) systems suitable. Unfortunately, the early development and adoption of residential rooftop solar PV systems are expected to face numerous constraints. This paper investigates the factors that impact the residential rooftop solar photovoltaic adoption in Qatar. Through analyzing the response of a general public sample, we hope to prove the hypothesized factors by aiming at testing their solar systems knowledge and awareness. The result of the study will provide insights on how the public perceives solar panels, along with factors the government needs to address to ensure successful public adoption of residential solar rooftop systems in Qatar.

The role and benefits of residential rooftop photovoltaic prosumers in Brazil

With the declining costs of photovoltaics (PV), a recent and widespread uptake of residential rooftop PV is underway in Brazil and many other sunbelt countries. Electricity consumers produce some or all their energy and become prosumers = producers + consumers. We present a method to evaluate the role and benefits of residential rooftop PV to prosumers and show a case-study using one of the 1250 PV-powered households in the “Celesc PV Bonus Project”, promoted by the local distribution utility Celesc to demonstrate our method in Florianópolis-Brazil. The methodology was divided into five principal stages: (i) Solar resource at the site; (ii) PV system performance indicators; (iii) Consumption profiles; (iv) CO2 emissions avoided and; (v) Comparative analysis between the individual PV rooftop case study with the average of PV households in the Florianópolis region. From the utility's perspective, the annual electricity consumption was reduced by 18% after PV integration. From the prosumer's perspective, the total annual consumption increased by 8%. However, the annual reduction in electrical utility expenses was 54%. The adoption of rooftop PV in residential households in Brazil was demonstrated to be advantageous, and payback times are still on a downward trend due to the continuing price reductions experienced by the PV technology.

Residential rooftop PV power generation to support cooling loads and national targets in Saudi Arabia

Saudi Arabia (SA) has a high per capita electricity consumption, predominantly supplied from fossil fuels. The residential sector accounts for about 50% of total electricity consumption with approximately 70% of which is used for air-conditioning (AC) loads. This research investigates the role of rooftop photovoltaic (PV) systems to displace cooling loads, hence reducing residential electricity demand. Daily and annual electrical demands were monitored in a villa in Jeddah, and a range of PV systems were modelled to determine their ability to support AC and other household loads. Seasonal performance data of such systems were compared to monitored load variations to understand variability and yields. The monitored electrical demand of the villa was in the range 66-167 kWh/day which was used to estimate the required PV systems’ capacities. The results indicate that PV systems in the range 2-10 kWp present significant shortfall to support the full demand. However, a 15kWp system was found to meet the daytime total loads. These results indicate that appropriately sized rooftop PV-systems can shave-off peak air-conditioning loads. The paper discusses the importance of utilising building integrated PV in such applications in SA, and highlights the need for dissemination at scale through country wide policy framework.

A Techno-Economic Comparative Study of a Grid-Connected Residential Rooftop PV Panel: The Case Study of Nahr El-Bared, Lebanon

Lebanon suffers from daily electricity shortages. The country has paid much attention to renewable energy sources, particularly solar, to gradually replace conventional energy. Installing a photovoltaic (PV) system becomes increasingly attractive for residential consumers due to the rising electricity tariff rates while it reduces the dependency on domestic power generators. No known study has dealt with the investigation of potential grid-connected rooftop PV systems with various sun-tracking modes and PV technologies in Nahr El-Bared, Lebanon. Consequently, the main objective of the current paper is to investigate the feasibility of a 5kW grid-connected PV system of various technologies (mono-crystalline silicon and poly-crystalline silicon) and sun-tracking modes including fixed tilt and 2-axis systems for rooftop households in Lebanon. The Nahr El-Bared camp was the case study was of the paper. RETScreen Expert software was used to evaluate the techno-economic performance of the proposed systems. The results show that the annual electrical energy from a fixed 5kW PV panel tilted at an optimal angle ranged from 8564.47kWh to 8776.81kWh, while the annual electrical energy from the PV tracking system was within the range of 11511.67-12100.92kWh. This amount of energy output would contribute significantly to reduce the energy shortage in the country. A typical household was selected to establish a load profile and load supply during both grid availability and outage periods. The highest energy consumption that can be covered by the PV systems was recorded during the spring and summer seasons. Also, the average energy production cost ranged from 0.0239 to 0.0243$/kWh for all the proposed systems. It was concluded that a 5kW grid-connected rooftop PV system could be economically justifiable. Finally, this study tried to increase the awareness about utilizing PV sun-tracking systems and the feasibility of small-scale grid-connected rooftop PV systems in the selected regions. The results of this research can help investors in the energy and building sectors.

Bundling residential rooftop photovoltaics with energy efficiency upgrades: does it really pay off?

Using data from a survey of solar adopters in the USA, the present paper examines the effect of adding insulation on electricity bill savings. We identify whether solar adopters added insulation to their house close to the time of rooftop photovoltaics (PV) installation as a bundling strategy, and examine whether such decisions are correlated with higher electricity bill savings. We find that only 7% of solar adopters in the sample ended up bundling their PV installation with additional insulation. About 58% of solar adopters in the sample have not added insulation at all. The evidence in the present study suggests that solar adopters who choose the bundling strategy have larger, older houses, located in counties with higher electricity prices than those adopters who did not add insulation at all. Results show that while all solar adopters who choose the bundling strategy have a higher average dollar amount of savings, only those with high initial bills end up with a higher percentage of savings. The results of the present study provide some insights into the energy decision-making of households and provide some input for policies focused on combining renewable energy with efficiency standards.

Increasing electric vehicle hosting capacity and equality for fast charging stations using residential photovoltaics in medium‐ and low‐voltage distribution networks

To achieve broad installation of electric vehicles (EVs), it is important to deploy fast EV charging stations at many points without distribution network reinforcement. This study develops a methodology for evaluating the hosting capacity for fast EV charging loads under medium‐ and low‐voltage (MV and LV) distribution networks with bus‐voltage and line‐current constraints; hence, the promising combination of fast EV charging and rooftop photovoltaic (PV) generation in distribution networks is analyzed. In particular, on a sunny day, the active power output supplied by rooftop PVs can be used to mitigate the voltage drop problem for end‐use residential customers. On a cloudy day, even though the active power output is smaller, the residual inverter capacities of rooftop PVs can be used to generate reactive power from those systems. In addition, in order to evaluate the spatial equalization of the EV hosting capacity at fast charging stations, an equalization factor of the spatial distribution is proposed, which is obtained as a percentage of the EV hosting capacity in the equally maximized case over that in the simply maximized case. The equalization factor can be improved from approximately 33 to 70% using the active and reactive power outputs from residential rooftop PVs. © 2019 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Assessment of economic benefits of battery energy storage application for the PV‐equipped households in Finland

Significant growth in residential solar photovoltaic (PV) installations and the ongoing decline in battery costs have increased interest in household solar battery energy storage projects in Finland in recent years. Among various potential applications, considerable attention is drawn to the use of the battery energy storage system (BESS) for the purpose of the households’ self-consumption enhancement. This study presents the results of a techno-economic study of the LiFePO4-based battery storage added to residential roof-top PV installations in Finland to maximise self-utilisation of on-site solar energy generation. Using a comprehensive DC model of BESS, the battery charge and discharge levels under the typical household load and PV production conditions are simulated. The estimates of the average retail electricity prices are used to assess the value that the customer-sited solar battery storage can provide to the household end-users in Finland. The economic attractiveness of the battery storage projects is evaluated considering the present and forecasted BESS costs and the electricity tariff levels in Finland and the conditions for profitable operation of the solar energy storage systems are determined.