Residential PV Research Articles

Tecno-economic evaluation of residential PV systems under a tiered rate and net metering program in the Dominican Republic

This article presents a study of the profitability of Residential Photovoltaic Systems (RPVS), through a techno-economic model based on the Net Metering Program (NMP) and tiered rate in the Dominican Republic (DR). This work seeks to identify profitable investment options in RPVS according to the level of monthly consumption of customers and the effect of the Tax Credit (TC). The methodology consists of maximizing the Net Present Value (NPV) to obtain the Payback Time (PBT) and the Internal Rate of Return (IRR). Without TC, the IRR was from 9.0 % to 23.0 % and the PBT was from 9.91 to 4.46 years for Average Monthly Electricity Consumed (AMEC) of 242 kWh and 1594 kWh respectively. At all levels of electricity consumption chosen, surplus generation at the end of the year was required to maximize the NPV; the numerical simulation showed oversized RPVS in relation to the energy demanded, between 25 % and 84 %. To maximize NPV, the lowest installed capacity was 3.28 kWp due to the increase of LCOE on RPVS for low consumption customers.

Driving on Sunbeams: Interactions Between Price Incentives for Electric Vehicles, Residential Solar Photovoltaics and Household Battery Systems*

I discuss how electric vehicles (EVs) link transportation externalities to the regulations that govern our electricity markets. Specifically, I contrast the consequences of the incentives faced by joint EV and residential PV adopters under a system of monthly net metering to those under a system of instantaneous metering with feed‐in tariffs and behind‐the‐meter own consumption. I also discuss how, even within Australia, households under new solar PV contracts and early adopters under legacy contracts face very different private costs of operating EVs, which have environmental and congestion implications. I briefly discuss how these incentives interact with the profitability and environmental benefit of household battery systems. Finally, I comment on how these short‐term incentives are likely to evolve in the longer run transition to a much cleaner grid and warn about the potential negative distributional impacts of using purchase subsidies to accelerate the adoption of these technologies.

Reconfigured Photovoltaic Model to Facilitate Maximum Power Point Tracking for Micro and Nano-Grid Systems

PV systems are a popular energy resource, prevalent worldwide; however, shade faults manifested in PV systems limit its power conversion efficiency. The occurrence of multiple power peaks and their location are highly uncertain in PV systems; this necessitates the use of complex maximum power point tracking algorithms to introduce high voltage oscillations. To address this issue, a new reconfigurable PV array to produce a global maximum power point (GMPP) algorithm close to the Voc regions was introduced. This enables the use of a simple Perturb and Observe (P&O) algorithm to easily track GMPP. For reconfiguration, a simple 5 × 5 PV array is considered, and a new physical relocation procedure based on the position square method is proposed. Performance of the proposed reconfiguration model is tested for four various shade events and its row current evaluations are comprehensively analyzed. Furthermore, evaluations of fill factor, mismatch loss, and power loss are quantitatively compared against Dominance Square and TCT schemes. Since the power enhancement is ensured in a reconfigurable PV array, the fixed reconfiguration is tailored to suit residential PV and microgrid systems. For MPP evaluations, hardware demonstrations are performed with a lab scale prototype model developed with a PV simulator and a DC–DC power electronic interface. The I–V characteristics of conventional and reconfigured models are programmed into the simulator and the use of the hill climbing algorithm is validated. To analyze the voltage and power oscillations with MPP tracking, the PSO algorithm is also tested for two test patterns and its results are comprehensively studied.

The installation of residential photovoltaic systems: Impact of energy consumption behaviour

Numerous electricity consumers tend to start consuming energy excessively after installing a photovoltaic system. In Jordan, almost all residential PV systems are grid connected and operate by net-metering agreements. Therefore, an increase in consumption after the installation of PV systems can result in a huge overload on the national electric grid. The challenge this presents is to find a specific level of comfort that will also protect the environment by saving energy. This paper examines the effects of residential photovoltaic systems on energy consumption and determines whether an increase or decrease occurs after installing these systems. This research was conducted to tackle the excessive energy consumption that occasionally occurs after installing renewable energy systems, especially in the residential sector in Jordan, and ascertains whether a pattern exists in the increase or decrease. Local energy consumption data within the period between 2016 and 2020 for 150 households in the governorates: Irbid, Ajloun, Al-Mafraq, and Jerash, as well as the municipality of Ar-Ramtha, were sampled after installing residential photovoltaic systems. Several attempts to correlate the results with key factors are also presented, the purpose of which is to limit some of these to reduce energy consumption after installing residential photovoltaic systems. The results indicate that 88% of households experienced a uniform increase in energy consumption after installing residential photovoltaic systems across the four governorates and the municipality. An average 41% increase in energy consumption was found with results varying across all studied areas but all exhibiting an overall incremental increase. Furthermore, the average share of self-consumed energy out of the total energy generated by PV systems was found to be 27.7% for the studied population, indicating the need of regulatory interactions to alleviate the pressure on the national electric grid, and to ensure the maximum benefits for PV systems’ installers.

Centralized peer-to-peer transactive energy market approach in a prosumer-centric residential smart grid environment

Transactive energy trading, control, and management have gained much importance, receiving significant interest from both industry and academia. As a result, new strategies for its development and implementation are emerging. Prosumage, which combines household loads with solar PV and battery storage systems, has been presented as an effective technique for facilitating the integration of renewable energy sources while reducing distribution grid stress. Therefore, this paper proposes a grid-connected prosumer-centric residential smart community that uses cooperative game theory to exchange, regulate, and plan surplus energy generated by distributed energy resources (DERs) with the other neighbouring prosumers with energy deficits. The energy community considered in this work comprises ten identical prosumers (residential load, solar PV, and battery storage system), an energy community manager, and an energy retailer, all of whom are linked as a group to a distribution grid. The proposed market model seeks to examine the economic benefits of such renewable sources participating in centralized transactive energy trading. A centralized approach is adopted in the transactive energy trading among the ten proactive prosumers and the power grid through an energy community manager that administers trading activities inside the energy community. An optimization model is proposed in the centralized transactive energy trading market to optimize the financial benefits of rooftop solar PV-battery systems. The proposed model will not only optimally exchange, plan, and regulate the community domestic load, but it will also minimize total energy costs, increase system operation efficiency, and reduce system operating stress and carbon emissions.

Technoecologies of Solar Commoning: Activating the Immanent Potentials of Solar Infrastructure, Practices and Affect

In the context of accelerated climate crisis this article investigates the energetic-political possibilities of solar energy in the Czech Republic. In the absence of solar cooperatives, the article examines residential PV installations and a ground-mounted solar mono-plantation as a terrain for possible commoning. It proposes technoecologies as a framework and tool to not only focus on what solar infrastructure brings together, but also what is left out or disarticulated in specific arrangements but can be seen as infrastructure’s productive “limits” that entail possibilities for differential inclusion, regeneration, and care. Ethnographic technoecological analysis shows how unexpected plant growth within the plantation points to multispecies refuges transforming the electric monoculture, and how electrical rewiring could connect PV arrays to households in multiple occupancy buildings (paneláky) in ways that enable new forms of sharing and joyful squandering of electricity in times of energy abundance.

Economics and policy implications of residential photovoltaic systems in Italy's developed market

This work quantifies the economic advantage of a 110% versus a 50% subsidized tax deduction for installing new residential PV systems in Italy using net present value as an indicator. The results show that the percentage of self-consumed energy significantly impacts the profitability of these systems. The break-even point analysis identifies the values at which profitability occurs depending on different policy scenarios. In addition, it is pointed out that in some contexts, the economic benefits to the state are greater than those to the consumer in the scenario involving a different selling price.

Social network and villagers’ willingness to adopt residential rooftop PV products: A multiple mediating model based on TAM/PR theory

Facing the promise of “carbon neutrality” and “carbon peak”, China’s vast rural areas will be the main front of energy conservation and emission reduction in the future. From the perspective of social capital, this paper combined TAM and perceived risk theory to construct a hypothesis model. Based on 617 rural survey data, structural equation model was used to reveal the influencing factors of the willingness to adopt residential rooftop PV products in rural China. The results show that: 1) social network has a significant impact on the willingness of villagers to adopt rooftop PV products. 2) Perceived usefulness, perceived ease of use and perceived risk play multiple mediating roles. 3) The parallel mediating effect of villagers’ perceived risk on the relationship between social network and adoption intention is much higher than the other two paths. 4) The chain mediating effect of perceived risk and perceived ease of use on the relationship between social network and villagers’ adoption intention is much higher than the other two paths. This study provides rich policy implications for rural renewable energy promotion and energy transition in China and other developing countries.

Implications on EROI and climate change of introducing Li-ion batteries to residential PV systems

In this study, we investigate the sustainability aspect of residential PV installations combined with batteries — with a focus on EROI (Energy Return On Invested Energy) and CO2 reduction potential. We pay special attention to situations where an excess of photovoltaic power generation is not allowed to be fully fed into the distribution grid and has to be (partly) curtailed. To this extent, we estimate the impact of residential solar batteries in three different European countries: Switzerland, Norway, and Spain. The combined EROI (PV coupled with battery) was shown to be greater for all battery sizes up to 30 kWh compared to a scenario where excess PV production would be curtailed, with Spain’s EROI almost doubling from around 8 for the case of no battery to 15 for an 18 kWh battery. For Switzerland and Norway, the EROI is improving by about 50% to 11 and 9, respectively, with the ideal size being smaller at 12 kWh. Optimal battery sizes were also calculated for different curtailment thresholds, which are set to increase in the coming years due to higher PV penetration in national power grids. Residential solar batteries were demonstrated to be a viable addition in all geographical settings from a Net Energy Analysis point of view. When considering CO2-equivalent emission reduction potential of a PV plus battery system, the local grid’s CO2 intensity is decisive, increasing the benefit in countries such as Spain and Switzerland, but worsening overall impacts in Norway for oversized batteries.

Energy and economic potential for photovoltaic systems installed on the rooftop of apartment buildings in Jordan

Photovoltaic systems installed on building rooftops can assist in reducing the issue of increasing electricity demand and simultaneously meeting the demand for environmentally sustainable energy systems. Despite the challenges facing Jordan's energy sector and the necessity of incorporating renewable resources to mitigate the effects of climate change and growing electricity demands, no one has yet analyzed the electricity output and economic viability of installing PV systems on the rooftops of apartment buildings in Jordan under different climate zones. Accordingly, this study aims to determine whether installing PV systems on apartment building rooftops in Jordan's various climate areas would be economically feasible and determine the potential power generation from such systems over their lifetime (25 years). Polysun simulation software is utilized to calculate electricity production, and a comparison method is used to assess the electricity consumption and production, and to compare the economic viability based on a payback period and net present value indicators under different tariff schemes. Scenarios are different in the tilt angles, azimuth angles, space between arrays, and accordingly different capacity and installation areas. The results indicated that electricity production from PV systems installed on the rooftops of apartment buildings can cover in the best scenario (Azimuth 90° and −90°, Tilt: 7°), depending on the location of the buildings, from 76% to 86% of their current electricity use and 25%–29% over 25 years. The Payback period (PBP) in the same case is between 3.8 and 4.6 years under different tariff schemes, which consider reasonable. While the net present value (NPV) is between 62,000$ and 77,500$ under different tariff schemes. According to the findings, residential PV systems are a practical choice for Jordan's energy management.

Towards a dramatic reduction in the European Natural Gas consumption: Italy as a case study

In recent months, gas prices have reached unprecedented levels, hurting the European economy and exacerbating energy poverty conditions. This paper deals with investigating measures for a rapid reduction in the Italian natural gas (NG) consumption. The aim is to assess and quantify energy, economic, social and environmental impacts of different strategies to be implemented promptly. Several solutions, such as utility and residential PV systems, Wind plants, biomethane, green hydrogen and heat pumps, have been analysed. Different implementation levels of such solutions have been simulated in combination with each other by means of the MATLAB Toolbox for EnergyPLAN. The NG Abatement Cost (NGAC) has been calculated. That indicator allows an immediate evaluation of economic benefits comparing it with current and future NG spot prices and potential import alternatives. The NGAC of the best strategies is between 40 and 70 €/MWh depending on the amount of achieved savings. Less than 80 billion in total investment leads to a NG reduction of 75 TWh/year at an average abatement cost of about 70 €/MWh. That entails an employment impact of 640,000 temporary jobs and 30,000 permanent jobs along with an emission reduction of 21.5 MtCO2/year. Under the highest implementation of such measures, future average NG spot prices higher than 50 €/MWh allow to reduce GHG emissions implying decarbonisation costs lower than 80 €/tCO2. Furthermore, three Carbon Abatement Cost curves by changing the NG prices have been elaborated. The findings of this work show how current high NG prices can be an opportunity to speed up the transition process towards decarbonised energy systems.

Roles of diffusion patterns, technological progress, and environmental benefits in determining optimal renewable subsidies in the US

In this paper we develop an integrated model to identify optimal subsidy schedules for clean energy technologies that maximize social benefits less subsidy costs. The model uses historical cost, adoption, and emissions data and accounts for both environmental and technological progress benefits of the subsidy. An alternative analytical model is also presented to analyze key technological features affecting subsidy design. We focus on three important factors in determining the social benefits of subsidizing the use of clean energy technology: the price (or cost) sensitivity of adoption, induced cost reductions through learning, and environmental benefits. We quantify how distinct profiles of these three factors result in qualitatively different optimal subsidy plans for utility wind and residential solar power in 13 electricity grid regions in the US. Results show that optimal subsidy schedules for utility wind depend on the region, starting at $20–60/MWh, and are roughly constant over time. In contrast, optimal residential solar subsidies either decline over time (starting from $8–70/MWh) or are not desirable (subsidy of zero). The results imply that the optimal subsidy for utility wind is justified mainly through the direct environmental benefits, unlike residential solar PV in which the subsidy is primarily justified by indirect technological progress benefits.

How prices guide investment decisions under net purchasing — An empirical analysis on the impact of network tariffs on residential PV

Within the regulation of net purchasing, investment incentives for residential PV depend on the remuneration for grid feed-in and the consumption costs that households can save by self-consumption. Network tariffs constitute a substantial part of these consumption costs. We use postcode-level data for Germany between 2009 and 2017 and exploit the regional heterogeneity of network tariffs to investigate whether they encourage to invest in PV installations and evaluate how the nonlinear tariff structure impacts residential PV adoption. Our results show that network tariffs do impact PV adoption. The effect has increased in recent years when self-consumption has become financially more attractive, and the results confirm the expectation that PV investments are driven by the volumetric tariff. Policy reforms that alter the share between the price components are, thus, likely to affect residential PV adoption. Further, with self-consumption becoming a key incentive, price signals can effectively support the coordination of electricity demand and supply in Germany.

Comparative Efficiency and Sensitivity Analysis of AC and DC Power Distribution Paradigms for Residential Localities

The new millennium has witnessed a pervasive shift of trend from AC to DC in the residential load sector. The shift is predominantly due to independent residential solar PV systems at rooftops and escalating electronic loads with better energy saving potential integrated with diminishing prices as well as commercial availability of DC-based appliances. Comprehensive sensitivity analysis considering the real load profile is missing in the present body of knowledge. In order to fill that gap, this paper is an attempt to include a comprehensive sensitivity analysis of the DC distribution system and its simulation-based comparison with its AC counterpart, considering the real load profile. The paper uses the Monte Carlo technique and probabilistic approach to add diversity in residential loads consumption to obtain an instantaneous load profile. Various possible scenarios such as variation of standard deviation from 5% to 20% of mean load value, PV capacity variation from 1000 W to 9000 W, and variation in power electronic converter (PEC) efficiencies are incorporated to make the system realistic as much as possible maintaining a fair comparison between both systems. The paper concludes with the baseline efficiency advantage of 2% to 3% during the day for the case of the DC distribution system as compared to the AC distribution system.

A framework to estimate the large-scale impacts of energy community roll-out

The gradual enactment of legislation for energy communities in individual European countries has increased the public awareness of these novel concepts. While the establishment of individual, isolated energy communities is unlikely to have any far-reaching effects, it is presumed that the large-scale roll-out will indeed significantly impact different stakeholders. Since the diffusion of energy communities is expected to gain momentum within the next years, this study aims to provide a framework to assess the impact of a large-scale roll-out of solar-PV based energy communities. This nine-step framework provides guidance for determining the number of buildings per type and roof tilt, assessing the usable rooftop area for PV installation and realistically installed PV capacities, estimating the number of future residential PV systems based on renewable expansion plans, determining the shares of buildings to be equipped with PV systems, setting up model energy communities, and upscaling. The nine-step framework is not only described theoretically but also applied to Austria as a case study. Thereby, specific focus is put on Austria's rural areas and thus the single-family building stock. Results indicate the impact of a large-scale roll-out of renewable energy communities on participants' electricity bills, electricity suppliers' sales, and grid operators revenues due to reduced grid tariffs for inner-community electricity transfer. The ability to determine the future impacts of energy community roll-out supports stakeholders in their proper planning towards an energy landscape that includes energy communities.

Life cycle assessment (LCA) of a battery home storage system based on primary data

While the market for battery home storage systems (HSS) is growing rapidly, there are still few well-modelled life cycle assessment (LCA) studies available for quantifying their potential environmental benefits and impacts. Existing studies mainly rely on data for electric vehicles and often lack a thorough modelling approach, especially regarding the peripheral components. This paper presents a full cradle to grave LCA of a Lithium iron phosphate (LFP) battery HSS based on primary data obtained by part-to-part dismantling of an existing commercial system with a focus on the impact of the peripheral components. Additionally, alternative battery chemistries (Sodium ion battery (SIB) and two lithium nickel manganese cobalt oxides, (NMC811,and NMC622) are investigated under the consideration of the same periphery. This approach allows a comprehensive comparison between present and emerging cell chemistries that can be potentially considered for an HSS.The total greenhouse gas emissions of the HSS are 84 g CO2eq/KWh of electricity delivered over its lifetime in a residential PV application, or 31 g CO2eq/KWh over lifetime when excluding the use-phase impact. The peripheral components contribute between 37% and 85% to the total gross manufacturing impacts of the HSS, depending on the considered cell chemistry and the impact category. Especially the inverter plays an important role, and its impacts are significantly higher than those obtained when using the standard ecoinvent dataset, indicating that the contribution of power electronics might often be underestimated when using this dataset. In terms of cell chemistries, the considered SIB turns out to be not yet competitive with LIB chemistries due to its lower energy density and lifetime, but might become so when reaching similar lifetimes.

What's driving solar energy adoption in Brazil? Exploring settlement patterns of place and space

The energy transition is forcing power systems to face exceptional transformations, with the rise of the distributed generation systems, and the urge of prosumers. This paper aims to investigate the influence of settlement patterns on residential photovoltaic adoption in Brazil, under a cross-section structure, using the Poisson Pseudo Maximum Likelihood estimator. Other key drivers are also included as control variables in the analysis. I benefit from a rich dataset of economic, social, housing, and environmental variables for 310,120 census sectors. Variables such as rural/urban dummies or population/housing density, used in previous papers to test for association between settlement patterns and residential PV adoption poorly represent the real relationship between these dimensions. The results of this paper ratify a U-shape relationship between urbanization degree and household solar power uptake. Satellite areas in the surroundings of great urban centers are more likely to present households equipped with photovoltaic systems in Brazil. Besides, the number of housing units, average income, solar resource potential, gender, education, ethnicity, age, housing type, and housing size play an important role in the explanation of the dynamics of household photovoltaic adoption. Policy design must take into consideration these effects in order to democratize photovoltaic home uptake.

Policy assistance for adoption of residential solar PV in India: A stakeholder-centric approach for welfare optimization

This paper presents a comprehensive analysis of the consumer-centric business model for rooftop solar PV installations in India. We explore areas where potential policy interventions may be introduced to improve collective stakeholder benefits and incentivize more domestic consumers to adopt rooftop solar power generation in their premises. The proposed policy framework optimizes Feed-in Tariff (FiT) rates, PV capacities and Average Billing Rates (ABRs) towards maximizing stakeholder benefits. The stakeholders considered are the consumers/prosumers and the utility. Case studies with three residential prosumers of different demand and generation profiles are presented. The models for utility profit and prosumer savings are developed, and a multi-objective problem is formulated with FiT, generation capacity (as a function of demand) and ABR as decision variables. The pareto-optimal front is identified for prosumer and utility benefits and suitable points with reasonable tradeoffs are selected based on sensitivity analysis of the impact on collective welfare. The suitability of prevailing tariff and FiT rates of two Indian utilities namely, MSEDCL and TATA POWER, Delhi are studied, and their impact on prosumer savings and utility profits is brought out. The workflow to fix tariff, FiT and local PV capacities in active residential distribution systems is devised, providing the policymakers an effective decision-making tool.

Techno-Economic Analysis of Grid-Connected PV Battery Solutions for Holiday Homes in Sweden

Grid-connected PV battery systems for private homes are becoming increasingly popular in many countries, including Sweden. This study aimed to evaluate the techno-economic feasibility of such distributed, grid-connected PV battery systems for single homes at a Swedish holiday location. It was especially of interest to investigate the impact of demand charges, as they are frequently introduced by utilities in Sweden and are also common in popular winter sport regions. Grid-connected PV battery systems were sized and optimized based on their net present cost. Load patterns, incentives, demand tariff structures and electricity price variation were used to study the sensitivity of the obtained results. Grid-connected residential PV battery systems were found to be equally profitable compared to grid-connected PV systems without batteries when demand charges were applied. When the load profiles had peak loads throughout the whole year and the batteries were large enough sized to shave many peaks, grid-connected PV battery systems had slightly higher profitability than grid-connected PV systems without batteries. The total savings also depended on the actual rate of demand charge. The good profitability we found greatly depends on the current state incentives for these systems in the form of tax credits for surplus electricity and investment costs. Removing the tax credit for surplus electricity would reduce the savings generated by a grid-connected PV system without batteries significantly more than for grid-connected PV systems with batteries.

Rooftop solar PV and the peak load problem in the NEM's Queensland region

Over the period 2016–2021 Australia's National Electricity Market (NEM) experienced an investment supercycle comprising 24,000 MW of renewables. One of the more intriguing aspects of the supercycle was a partial shift of investment decision-making from utility boardrooms to households – rooftop solar PV comprised 8000 MW of the 24,000 MW total. In NEM regions such as Queensland, take-up rates have now reached 41.8% of households, currently the highest take-up rate in the world. There is a distinct mismatch between residential peak demand and solar PV output, which tends to suggest any peak load problem will be exacerbated. When the contribution of rooftop solar PV is abstracted to the power system level these results reverse. The partial equilibrium framework of Boiteux (1949), Turvey (1964) and Berrie (1967) has historically been used to define the optimal plant mix to satisfy demand growth. In this article, their partial equilibrium framework is used to define conventional plant ‘dis-investment’ in the presence of rising rooftop solar PV and utility-scale renewables in an energy-only market setting. Queensland's 4400 MW of rooftop solar displaces 1000 MW of conventional generation in equilibrium, 500 MW of peaking plant and somewhat counterintuitively, 500 MW of baseload coal plant – falling ‘minimum system demand’ being a driving factor. The NEM's energy-only market and its $15,000/MWh price cap proves tractable through to a 50% renewable market share, but relies critically on frictionless coal plant divestment and bounded negative price offers.