Use Of Renewable Energy Sources Research Articles

Renewable energy sources and storage batteries for electrification of Russian decentralized power supply systems

The use of renewable energy sources (RES) and storage batteries (SB) in decentralized power systems is a cost-effective way to supply power to consumers. In this case, storage batteries are one of the most important system components. The significance of storage batteries is conditioned by a stabilizing effect obtained at generation from RES that are defined by stochastic oscillating functions. However, it is worth noting that storage batteries also improve the cost-effectiveness of such systems by reducing consumption of diesel fuel. This is particularly noticeable at night when load is the least and the use of diesel generators is inefficient. One of the most important points is the determination of potential internal processes of aging and breakdowns that occur in storage batteries during operation. The use of a tested model for categorization of storage batteries according to the operating conditions makes it possible to take account of these factors at the stage of a system design. The paper presents a detailed analysis of decentralized power supply system Verkhnyaya Amga. The focus is made on the cost-effectiveness of a combined use of RES with storage batteries, annual saving of diesel fuel, operating parameters. The research reveals hidden problems that represent various uncertainties that affect greatly the economic and operation parameters of the system.

The Consumption of Renewable Energy Sources (RES) by the European Union Households between 2004 and 2019

The paper provides the analysis of fuel and energy transition in households sector and its sustainable development in the period 2004–2019. The main purpose of the paper is to determine the development trends in the use of renewable energy sources (RES) in the EU countries household sector in 2004–2019, to recognize the state of development and functioning of the studied area as well as to indicate their successes and shortcomings in observed reality. The article employs the results of Energy balance sheets from Eurostat. The research entity were households from 28 European Union countries, with particular emphasis on households from Poland and selected neighboring countries. The research subjects there were different sources of renewable energy used by households, i.e., solar thermal system, geothermal technologies, primary solid biofuels, charcoal, biogases, blended biogasoline, blended biodiesels, ambient heat (heat pumps). To achieve the research objective a number of statistical measures ands methods, including cluster analysis and linear trend indicator applied. In the analyzed 16 years, an absolute and relative increase in the use of RES in the household sector was noticed. Taking into account the specificity of using RES in households, 6 clusters of countries were distinguished. In Poland, it was noted that there was a significant increase in the use of RES in households, with stagnation in the use of non-renewable energy sources, such as, for example, hard coal.

Using MCDM Methods to Assess the Extent to which the European Union Countries Use Renewable Energy

Abstract Energy security is one of the basic tasks carried out by individual countries. It is of great socio-economic and political importance and constitutes the basis for independent development of both economies and groups of countries. Access to adequate resources of affordable and environmentally neutral energy in the production process is the basis for sustainable energy development. Therefore, an important element of sustainable energy is its environmental neutrality. Currently, this condition is fulfilled to the greatest extent by energy produced from renewable energy sources (RES). Renewable energy development is taking place all over the world, but the European Union (EU) is a definite leader. In its energy policy, the importance and role of RES in the energy production structure has been growing systematically for many years. Introduced regulations and energy strategies caused member states to take extensive actions to achieve the set targets for RES. However, the large diversity of the EU countries makes this process occur with different intensity. Thus, it was justified to conduct research to assess the level of renewable energy use in the EU countries in a 15-year perspective (2004-2019). The research was based on a set of 4 indicators characterizing the use of renewable energy in the EU countries by means of the WASPAS method (from the group of MCDM methods). The results showed that a high level of RES use in the whole studied period was found in Sweden, Austria, Latvia and Finland, and a low level, for 2004, was found in Cyprus, Luxembourg and Malta, and for 2019 – in Luxembourg and Malta.

School Managers Perceptions towards Energy Efficiency and Renewable Energy Sources

Global economic growth is accompanied by increased energy demand, thus conventional fuels such as coal, oil and gas, which are the primary energy sources, are gradually being depleted. At the same time, the combustion of conventional fuel for energy production causes serious adverse effects on the environment and contributes to climate change due to the emitted greenhouse gases. For the above reasons, most of the developed and developing countries especially during the last decades, have introduced various incentives for the greater penetration of renewable energy sources (RES) in all sectors of the economy. Concerning the building sector, several measures have been adopted, including the promotion of energy efficiency and energy saving. A significant proportion of the building stock are the school buildings where students and teachers spend a significant proportion of their daily time. Teachers' attitudes and views, especially the school unit managers concerning the use of RES in schools, are important in the effort to rationalize and control energy use. This study was conducted through a structured questionnaire applied to a sample of 510 school managers in Greece's primary and secondary education. The school unit managerial role for the case of Greek schools is performed by the school principal who has both administrative and educational duties. Statistical analysis included the application of Friedman's test and hypothesis test on questions concerning school manager environmental perceptions and energy-saving habits. According to the results, Greek school managers have a high degree of environmental sensitivity, since 97.6 % agreed or strongly agreed that the main concern should focus on energy saving. Furthermore, 71% of the respondent reported to have good knowledge on solar energy, followed by 64% on wind energy while only 34% are knowledgeable on biomass. Almost all the respondents (99%) agreed that it is important to provide more RES-orientated education through the taught curricula. Concerning energy saving behaviour, around 90% reported that they switch off the lights when leaving the classroom and they close the windows when the air-condition is operating. Hypothesis tests revealed a relationship between the school managers' ecological beliefs, the energy saving habits in the school environment, and the recognition of the importance of environmental education. Conclusions highlighted the need to intensify environmental education programs in the school environment concerning RES in schools. This will lead to a higher level of environmental awareness of both teachers and students and therefore to a more dynamic behaviour towards the effort to “greenify” the school environment.

Economic aspects of perennial energy crops cultivation

Purpose. On the example of miscanthus and willow, to carry out an economic assessment of the efficiency of perennial bioenergy plants cultivation; to calculate the amount of compensation, which will reduce the payback period of investments into establishing the plantations. Methods. Field, laboratory, calculation. Results. The total input for the first three years of growing perennial bioenergy plants is as following: 80 900UAH/ha for miscanthus and 43 900 UAH/ha for willow. Meanwhile, the income from the sale of biomass during this period is only 22 000 UAH/ha for miscanthus and 24 000 UAH/ha for willow. Therefore, in order to ensure that the plantation payback does not exceed 3 years, it is necessary to provide compensation in the amount of about 60 000 UAH/ha for miscanthus and 20 000 UAH/ha for willow, which should be paid once in the year of the plantation establishment. Without such compensation, payback of miscanthus and willow plantation will be 7 and 6 years, respectively. If only the costs of planting material (rhizomes or cuttings) are compensated, the payback period of the plantations will be more than 4 years. Conclusions. The development of renewable energy sources (RES) should be considered as an important factor in raising the level of energy and economic security of Ukraine and reducing the anthropogenic impact of power production on the environment. Now, Ukraine has created a favourable legal and regulatory framework for the production and use of RES. Given the favourable soil and climatic conditions, the most promising type of RES for Ukraine is bioenergy, which is based on the feedstock of tailored bioenergy plants. In order to reduce the payback period of the investments in the establishmentof perennial bioenergy plantations, it is necessary to provide compensation for planting material and fertilizers in the following amounts: 60 000 UAH/ha for miscanthus and 20 000 UAH/ha for willow.

A COMPREHENSIVE ENERGETIC, EXERGETIC AND HEAT TRANSFER ANALYSIS OF A SOLAR ORGANIC RANKINE SYSTEM

Environmental concerns have been motivating the use of renewable energysources to meet sustainable requirements. In this context, concentrated solarpower driven by organic Rankine cycles has been classified as an up-andcomingtechnology to generate energy under low and moderate temperatures.In order to have a better understanding of the availability and utilization of thisenergy resource, the purpose of the present study is to perform acomprehensive energetic, exergetic and heat transfer analysis of a 200 kWsolar organic Rankine cycle through the presentation of the energy and exergyefficiencies and losses for each component; the exergy destruction at all stagesof the process; and the heat transfer behavior along the receiver. The thermalmodel was developed in Engineering Equation Solver and validated withliterature data. The solar collector was operated with Therminol 66 and theworking fluid employed in the power block was cyclohexane. The energeticefficiencies achieved in the solar field, power block, and overall system were64.97; 21.36; and 13.87 %, respectively. Considering the exergetic efficiencies,they were 27.37; 54.45; and 14.89 %, respectively. The solar resource variationshowed that the higher DNI value, the better the system performance.

STATE POLICY OF KAZAKHSTAN ON IMPLEMENTING OF RENEWABLE ENERGY SOURCES IN TEXTILE INDUSTRY COMPANIES

The article discusses the mechanisms of state support for the development of renewable energy sources (RES) in the Republic of Kazakhstan. The authors consider the prospects of using solar energy in the textile industry. The analysis revealed that the level of organization of work in companies in the field of energy conservation and energy efficiency of production depends on the following factors: timely observation of the current power supply and possible future energy potential; development and implementation of energy-effective measures; use of RES with purpose of saving energy resources. According to the authors, the dominance of electric and thermal forms of energy in the cost structure leads to a loss of competitiveness of the company's products in the textile industry. The article considers the transition to combined generation of electric and thermal energy in textile industry companies using renewable energy sources. The calculation of the energy saving coefficients of electric and thermal energy produced by the authors proved the possibility of reducing the cost of textile products by introducing renewable energy sources. The results of the assessment, based on the construction of a correlation and regression model, showed the economic efficiency of using renewable energy in the textile industry, while the authors recommend paying special attention to state regulation of tariffs and the auction price for renewable energy. Keywords : renewable energy sources, solar energy, textile industry. JEL Classifications: Q42, Q48, L60 DOI: https://doi.org/10.32479/ijeep.10659

ABOUT THE EXPEDIENCY OF USING ELECTROCHEMICAL STORAGES IN POWER SUPPLY SYSTEMS FOR NON-TRACTION CONSUMERS OF RAILWAYS FROM RENEWABLE ENERGY SOURCES

This paper focuses on the problem of analyzing expediency of using electrochemical storages in power supply systems for non-traction consumers of railways from renewable energy sources (RES). It is quite obvious that RES implementation in any national industry as a proper distributed energy source is too problematic if there is no possibility to accumulate it in good supply. The aim of this paper is to select the most appropriate electrochemical storage device for power systems for non-traction consumers of railways from RES. The methodology of research is based on modern methods of computational mathematics, statistics and information analysis using modern computer technology. Consequently, the analysis helps conclude that batteries are the most preferable for power lines. That especially concerns railway mains with RES use since the batteries have the best power characteristics.

Da li je pravo vreme za izgradnju velike solarne elektrane u Srbiji?

According to almost all estimates, significant investments in new renewable energy sources in Serbia are needed. Serbia has economically viable potentials of renewable energy sources (RES) (solar energy, wind energy, hydropower, biomass energy, geothermal energy, etc.), so the structure of the production mix in the electricity system should increasingly be based on renewable sources. In this paper, an attempt is made to answer the following questions: does Serbia need new production capacities, does Serbia need new production capacities from RES, and finally, which of the RES would be the most suitable at the moment? The paper assesses whether this is exactly the right moment to accelerate the process of energy transition in Serbia, as well as the opportunity to ensure a more sustainable growth and development through a faster transition to RES. It starts from the fact that increasing the production of electricity from RES, together with measures to increase energy efficiency and decarbonize energy production and consumption, is the backbone of the energy transition and at the same time the essence of Serbia's commitments by joining the Energy Community and accepting international climate agreements. The paper assumes that by increasing the efficiency of the energy sector and use of RES, European policy goals can be achieved in Serbia and that energy sector can be positioned as an engine of stability and sustainable economic development. Secondary effects will lead to increased sustainable employment, reduced public debt and increased competitiveness of the sector. Therefore, the energy transition should be seen as a development opportunity. The construction of large RES plants, especially large solar power plants in Serbia and joining the EU Green Deal, is certainly a signal that Serbia is well on its way to developing a modern, environmentally friendly, competitive and regionally integrated energy system. This will trigger the necessary investments in the modernization of the energy sector and enable the attraction of foreign direct investments. Achieving this vision requires decisive political action at the national and regional levels. Solar projects have the lowest levelized costs of produced kWh of electricity, they are the fastest to implement and they have the least environmental and social impact. Also, large installed capacity can be achieved through a series of large and medium-sized projects that would be territorially distributed in order to reduce the simultaneity of production.

An Appropriate Wind Model for The Reliability Assessment of Incorporated Wind Power in Power Generation System

The use of renewable energy sources (RES) by many power grids companies around the world has increased significantly in recent years. The trend towards the use of RES is mainly due to ecological problems and rising fuel prices related to conventional power generation. Wind power is an approved source for power generation among renewable sources that makes a positive contribution to the global, social and economic environment. Today, wind turbine generator (WTG) is a mature, abundant, and eco-friendly power generation technology, and much of the electricity demand is supplied by wind. However, the uncertain nature of wind speed poses a variety of challenges for the planning and operation of power systems. One of the problems in increasing wind power can be seen in terms of assessment of power system reliability. This paper presents a reliability assessment model of power generation systems (PGS), including WTG, by using an analytical method. The presented model in this paper applied to the Roy Billinton Test System (RBTS). The methodology and results presented in this paper are intended to provide useful information to planners or developers seeking to assess the reliability of PGSs, including WTG.

Atom Search Optimization Algorithm for Allocating Distributed Generators in Radial Distribution Systems

In recent years the use of renewable energy sources (RES) by many power grid companies worldwide has increased significantly. The trend towards RES use is mainly due to environmental issues and rising fuel prices associated with conventional electricity generation. This paper introduces a hybrid approach to find the optimal location and size of distributed generations (DG) in the radial distribution system (RDS). The proposed approach is based on the atom search optimization (ASO) technique to calculate the optimal allocation of DGs and power loss sensitivity (PLS) index to obtain the best buses for DGs installation in RDS. The presented approach is applied to IEEE 33-bus RDS to increase voltage profile and minimize the power losses. The results obtained prove that the developed approach can be highly effective in integrating DG into RDS compared to many other methods in the literature.

Energy benchmarking in educational buildings in the city of Kragujevac - possibilities for energy efficiency improvement

The implementation of energy efficiency measures and use of renewable energy sources in educational buildings can significantly contribute to reducing energy consumption, but also to CO2 emissions in the entire public sector. The paper shows the comparison of energy consumption indicators for 61 elementary school buildings which have previously been divided in 12 groups, according to the period of construction and size, based on the national typology called TABULA, as the first step of further study on how to use the renewable energy sources. The aim of this paper is to use the energy benchmarking process to select representative facilities which are suitable for applying renewable energy sources, for their further energy efficiency improvement. Indicators of annual specific electricity consumption and CO2 emissions per unit area [kWh/m2] and per user [kWh/user] were calculated. After that, from two groups (in which the highest electricity consumption and CO2 emissions are 68.37% and 74.53% of the total consumption/ emissions), one representative facility was selected.

Energy Clusters as a New Urban Symbiosis Concept for Increasing Renewable Energy Production—A Case Study of Zakopane City

One of the priority lines of action in Poland is to increase energy production from renewable energy sources (RESs). Based on the “Poland’s national energy and climate plan for the years 2021–2030”, Poland aims to achieve 21%–23% of RES share in gross final energy consumption by 2030. While coal is still the most important source of energy, new technological and organisational solutions for increasing RESs are being tested and implemented. Therefore, the creation of energy clusters based on the idea of urban and industrial symbiosis was first proposed by the Ministry of Energy in 2016. To date, there are 66 clusters in different regions in Poland, but only a few of them are active and innovative. One of them is located in the city of Zakopane, a mountain resort, which attracts about 3 million tourists annually and has developed the wide-ranging use of geothermal sources for energy supply and recreation. The paper aims to analyse the impact of the creation of energy clusters on the city’s development, including economic, social, and environmental aspects. The “willingness to pay” (WTP) method was used to calculate the impact of air pollution on Zakopane and to compare it with the Polish average to estimate the significance of the transformation to RESs in this tourist city. The results from the studies are as follows: health cost per capita in Zakopane is between 252.07 and 921.30 euro. The investigations presented can be the basis for recommendations in strategic documents in the field of regional development and environmental protection, especially on the use and promotion of urban symbiosis for increasing use of RESs.

Renewable Energy Sources as a Development Opportunity for Peripheral Areas

Summary Subject and purpose of work: The subject of this analysis and evaluation is the use of renewable energy sources in Poland, particularly in the Lubelskie Voivodeship, as a peripheral region. The purpose of this paper is to identify the role and evaluate the scale and effects of using renewable energy sources (RES), as well as the availability and absorption of financial resources for RES promotion. Materials and methods: The data were obtained from the Office of the Ruda-Huta Commune, the Regional Operational Programme Department of the Marshal Office of the Lubelskie Voivodeship in Lublin and the Department of European Funds of the Ministry of Energy, as well as Statistics Poland (GUS) and the literature on the subject. Results: In Poland the proportion of energy from renewable sources to the total primary energy generated increased in 2012-2018 from 11.73% to 14.46%. A new phenomenon, which has been highly significant for the development of this sector, is the use of innovative, small-scale technologies of energy generation from renewable sources, which created the foundations for the growth of a citizens’ energy sector, based on the initiative of the citizens and their communities. The use of RES contributes to reduced expenditures on the purchase of energy carriers and constitutes an effective method of implementing plans for developing a low-carbon economy and reducing low-stack emissions. Conclusions: The continuing disparities between the regions point to the need for active structural intervention to maintain economic, social and territorial cohesion, particularly in areas which are considered peripheral and have a very low GDP per capita. One of the preferred directions should be to support the use of RES.

The Potential of RES in the Reduction of Air Pollution: The SWOT Analysis of Smart Energy Management Solutions for Krakow Functional Area (KrOF)

Health impacts and a decrease in the quality of life caused by air pollution is a major problem worldwide. Krakow is one of the most affected cities in the EU by air pollution mostly caused by burning solid fuels in households’ furnaces. It is considered that the most effective remedies would be adequate spatial planning solutions and application of low-emission sources including renewable energy sources (RES). This article draws from the analysis of the use of RES as a means for reducing harmful emissions in Krakow Functional Area (KrOF). The inventories of renewable energy sources and systems were compiled by the authors as a part of the EU project “Smart Edge—Sustainable Metropolitan Areas and the Role of The Edge City”. Using the data from the inventories, a SWOT analysis has been carried out to identify factors that determine the smart management of the RES potential, particularly the decisions of households on the transition towards RES. The results of the analysis have shown that many actions have been taken at the national, regional, and local levels but the greatest influence bear the solutions initiated and implemented at the communal level. The conclusion is that legislative regulations should be combined with locally tailor-made instruments. The proposed method of analysis can be applied in other metropolitan areas as a diagnostic procedure supporting action planning to solve air-quality problems caused by distributed emission sources.

Designing a logo for renewable energy sources with public participation: Empirical evidence from Greece

This contribution looks into logos as a powerful designing tool which can promote the implementation of Renewable Energy Sources (RES) policy. Given the lack of universal logo which would communicate the RES-derived products and services effectively, we initially explored the public’s emotions, thoughts, perceptions, images, experiences, beliefs and attitudes towards RES and non-RES through their design illustration. Experts decoded a total of 769 RES and 737 non-RES designs of four different sample groups ranging from the less informed children to well-informed engineers, and defined the design variables of a RES logo. On the basis of these design guidelines, professional designers created 60 RES logos. Besides, 432 participants randomly selected evaluated the logos on a score scale from 1 to 6. Interdisciplinary, cross-cultural and semiotic analysis of the winner logo revealed that in order to promote the RES use, a logo should be of round shape; present a sense of movement; convey a clear positive message; embed natural elements in the composition of the image with various hues of green, white and yellow-orange colours; include visually acute, religious and cultural symbols, and carry connotations of personal and social responsibility. This is the first attempt of designing a RES logo with public participation.

Solar PV and Biomass Resources-Based Sustainable Energy Supply for Off-Grid Cellular Base Stations

Due to the technological revolution and higher user data demand, the telecommunication industry is expanding at an exponential rate. Fulfilling the increasing demand of energy for the rising cellular networks has become a great challenge to the network operators because of the limited reservation of fuel energy sources and the growing concern about global warming. Energy harvesting (EH) from renewable energy sources (RES) has become an overwhelming initiative to minimize energy deficiency and carbon footprints. This paper investigates the feasibility of solar photovoltaic (PV) and biomass resources based hybrid supply systems for powering the off-grid Long Term Evolution (LTE) cellular macrocell base stations (BSs) in Bangladesh focusing the technical, economic and environmental issues. In addition, the green energy sharing technique has been incorporated via a low resistive path for optimal use of RES. The proposed system has enough potential to achieve long term sustainability and reduction of pollution rates by fulfilling the future energy demand of BS. In this work, Hybrid Optimization Model for Electric Renewables (HOMER) simulation-based feasibility analysis is used to assess the optimal system, energy production, total net present cost (NPC), cost of electricity (COE) and greenhouse gas (GHG) emission depending on different system parameters. Furthermore, the performance of the network has been evaluated in terms of throughput and energy efficiency using Matlab-based Monte Carlo simulations. Results demonstrate that the proposed hybrid renewable energy powered BSs would be a reliable and longer-lasting green solution for the telecom sector while maintaining the quality of service (QoS). Finally, an extensive comparison with other systems has also been done to justify network validity.

Developing an energy informatics application for hybrid green buildings

Renewable energy sources are important in the green building for energy saving. The use of renewable energy sources needs energy management in hbyrid green buildings. By using an energy management system, the energy costs of hyrid green buildings can be systematically and regularly controlled. In other words, it provides each consumer to produce their own energy in their own building, and reduce the dependence to the central power grid. Besides, the change of electricity pricing according to hours can be seen as another parameter. The aim of this study is to develop an energy informatics application for energy management in green buildings. Resource management scenarious have been created according to regional atmospherical conditions. These scenarious were monitored via an energy source management interface. In this study, a software which have a visual interface was developed. This software conducts an energy management system for a hybrid green building which has three kinds of energy resource like utility, solar arrays and energy storage system. This software proposes an resource management system between these three types of resources.Proposed system depends on some scenarious which are interchangable according to external parameters such as; variability of the price of energy received from electric grid, seasonal factors, fullness level of the batteries were designed. In the scenarios of the electric loads, making them continuous and as cheap as possible were taken into consideration. With the developed software, it is aimed to monitor energy consumption of each scenario. Thus, an arrangement using cheap, continuous and environmentally friendly resources as possible as will be provided.

Comparative environmental life cycle assessment of electric and conventional vehicles in Lithuania

Abstract Electrification of city transport and the use of renewable energy sources (RES) in transport systems have become leading trends for sustainable transportation. Many researchers state potential environmental benefits of electric vehicle (EV) when integrating RES into production of electricity, which is needed to recharge the EV’s battery. However, it is still unclear under what electricity mix scenarios environmental advantage will be the most significant and what technologies/fuel type have a major impact on the environment. For this reason, the article presents a comparative environmental life cycle assessment (LCA) of a battery electric vehicle (BEV) and internal combustion engine vehicles (ICEVs) fuelled with petrol and diesel. Besides, LCA of BEV under different electricity mix scenarios, that are prognosticated for the years 2015–2050 in Lithuania, is assessed. The paper shows a complete life cycle, composed of “Well-to-Wheel” and “Cradle-to-Grave” analysis for conventional and electric vehicles. This study uses ReCiPe methodology including both midpoint and endpoint indicators in order to express the impact on the environment. The results at the midpoint level reveal that in terms of climate change BEVs of 2015 electricity mix generate 26 and 47% more greenhouse gas emissions than those of ICEVs fuelled with petrol and diesel, respectively. Although in 2020–2050 electricity mix scenarios oil is expected to be eliminated and the use of RES will be highly increased, ICEV-petrol is expected to be the most polluting, comparing to ICEV-diesel and BEV in 2020 and later scenarios. Similar results are revealed at the endpoint level, as ICEV-petrol has the highest environmental damage in all categories: human health, ecosystems and resources. Next comes ICEV-diesel with 28% less total environmental damage, followed by BEV of 2015 electricity mix with 42% less impact than ICEV-diesel. Finally, BEV with electricity mix of 2050 has 54% smaller impact than BEV with electricity mix of 2015.

Towards the nearly zero and the plus energy building: Primary energy balances and economic evaluations

In the construction sector, responsible for the greatest amounts of energy consumption and greenhouse gas emissions, nowadays a significant turning point in the current scenario that qualifies building approach is taking place. In recent years, the ambitious nZEB (nearly Zero Energy Building), a building with very high energy performance, in which energy saving, cost-optimal vision and user well-being are assessed in a comprehensive way, has found legislative and operational implementation. Moreover, the adoption of increasingly challenging energy targets today offers important opportunities for the energy requalification and improvement of the overall quality of the building stock, particularly in the field of renewable plants.Within this frame in the paper, as a contribution to the analysis of benefits deriving from the use of RES (Renewable Energy Sources) plants in buildings, in terms of primary energy, cost, and greenhouse gas emissions, an intervention aimed at the satisfaction of the electric demand of a residential building through a photovoltaic plant, in different configurations (grid connected, stand-alone and storage on grid) has been analysed. For each configuration, balances between energy rates (production, load, grid exchange and/or battery store/withdrawal) have been hourly assessed in order to evaluate the Net Present Cost at the end of plant life.Moreover, a yearly primary energy balance has been determined, taking into account also thermal energy required to guarantee thermal needs (provided by a methane boiler), together with produced CO2 emissions.