Energy Payback Period Research Articles

Adaptable pathway to net zero carbon: A case study for Techno-Economic & Environmental assessment of Rooftop Solar PV System

Several countries have a critical need to enhance their electricity production to satisfy the tremendously increasing energy demand and to minimize the black outs. Due to scarcity of fossil fuels and degrading environment, rooftop Solar Photovoltaic (SPV) can be a suitable renewable alternative of green and clean energy. In this paper, due to the techno-economic, environmental and social benefits of Solar PV, the modelling and planning of a solar PV plant to fulfil the energy demand of an academic building is carried out. The analysis is done including all the financial and environmental aspects considering recent market prices and future price escalation. A Modified Greedy Search based optimal planning of the SPV to minimize grid dependence considering load variation pattern with its assessment analysis for an academic building is proposed in this research work. The various financial parameters that affect the feasibility of Solar PV plant i.e., energy payback period, grid dependency, rate of investment return, economic payback period, rate of escalation with actual cost of electricity, annual maintenance cost, depreciation and taxation are considered and evaluated. The environmental factors related to the generation from Solar PV i.e., CO2 emission reduction and carbon credit are also included in analysis. The results obtained for the proposed Solar PV plant shows that the energy payback period is 8 years and IRR with depreciation and taxation is 21% (approx.) with net CO2 mitigation of 1199 tCO2 during the useful life span (25 years) of the plant.

Influence of Donated Pair of Electrons by a Nitrito-Group Ligand on the Solid-State Properties of Lead Sulfide Thick Films

In general, thick and thin films are developed to provide special properties that range from electrical properties, optical, mechanical and chemical properties that can satisfy the needs for specific applications in technology. Lead sulfide (PbS) is an example of such films. Lead sulfide thin films have been synthesized on glass substrates. Some of the advantages of PbS thin film in olar cell applications include low material consumption, shorter energy payback period, large area modules, monolithic integration, tuneable material properties, low-temperature processes, and transparent modules. PbS thin films help also help in preventing corrosion of metallic parts of many devices. They are also used to offer protection against wear in moving parts. Materials such as jewelry, wrist watches, and knives are often coated to avoid corrosion. For deposition of PbS thin films, lead acetate is used as lead precursor and for sulfur source thiourea, has been was used in many studies.in this study, three samples of lead sulphide thick films were deposited on microscope glass slides at varying nitrito-group ligand concentrations at room temperature using solution method. The nitrito group ligand has a capacity to coordinate a central metal {Pb) atom using two different sites. First, it can use the nitrogen (N) atom as donor atom (nitrito group) and the oxygen (O) as donor atom (nitrito group). Secondly, it can use a sulphur (S) atom as donor atom ( in a thiocyanate group) and nitrogen (N) atom as donor atom ( as in a isothiocyanate). The influence of nitrito-group ligand on the solid-State properties of PbS thin films deposited by chemical bath technique were investigated and characterized using UV-VIS spectrophotometer and Four-Point Probe (FPP) technique. They were analyzed graphically, and the results show that, the donated pair of electrons from the nitrito group ligand caused absorption edge to decreases towards longer wavelength region while band gap energy increase from 1.61eV to 3.71eV with increase concentration. On the sampled films, there was a consistent increase in the sheet resistance and electrical conductivity as the concentration of Nitrito-group ligand increases.

The Impact of Glazing Types and Window-to-Wall Ratios on Energy Consumption in Semi-arid, Mediterranean and Arid Climates

A reduction in energy consumption and energy efficiency improvement in buildings have become one of the main objectives in national and international energy policies. In an optimization process, and in order to find the most influential parameters to achieve net zero energy, several ameliorations need to be made to residential buildings. In this paper, two measures are discussed; the effects of locally available glazing types and window-to-wall ratios, tested under three different Algerian climates; semi-arid, Mediterranean and arid-climate. For the purpose of calculating energy use intensity savings, optimal values and payback periods for each of the mentioned measures the building information modelling software Autodesk Revit® and the energy simulation plugin Sefaira have been used. According to the findings, double glazing with Argon has the greatest potential for lowering the energy use intensity, whereas the window-to-wall ratios has a significant effect on the energy consumption of buildings in the studied climates, and the optimal ratio for a given orientation varies according to the type of glazing used. Moreover, very high payback periods were found compared to other countries, and only a few studied variables could be achieved with profitability. This paper is helpful for professionals who are responsible for decision-making during the design process of energy-efficient residential buildings.

Performance study of an active solar water curtain heating system for Chinese solar greenhouse heating in high latitudes regions

Thermal preservation and heat storage performance cannot be fully realized in the traditional design of the Chinese solar greenhouse (CSG) north wall. To increase greenhouse thermal efficiency and maximize solar energy utilization, researchers have divided greenhouse into the independent solar heating system as well as the independent north wall heat preservation system. The wall-mounted solar heating system used water as a medium with the characteristics of chemical stability, liquidity preference and high specific heat capacity for heat transport and storage have been developed. To explore and create a better suitable greenhouse thermal environment, we proposed an active solar water curtain heating system with a non-woven fabric liner between the two-layer polyethylene film coated with black water-based paint. The greenhouse heating load was estimated based on energy balance theories during the nighttime and the water mass for heat transfer was calculated. Field tests were carried out to verify theories and investigate the thermal performance of the system. The average heat collection ratio was about 80.1 % and 63 % of the stored heat was released at night with the 3.6 °C improvement in interior air temperature and 6.6 % reduction in interior air relative humidity. The heating COP of the system was 12.5 on average and the energy saving rate was 92 %. Besides, the greenhouse with the solar heating system can save energy consumption cost about 348 USD yr−1 as the cost of solar heating system can be repaid in 1.4 years. The system combined the energy balance method to design with more efficient thermal performance, energy conservation, utilization of solar energy and affordable payback period thereby creating a suitable thermal environment in the Chinese solar greenhouse, which is recommended for practical application.

Numerical and environmental analysis of post constructive application of PCM coatings for the improvement of the energy performance of building structures

In recent years, the post-constructive application of phase changing materials (PCMs) as coating to improve the thermal behavior of buildings, is gaining more ground. The question that arises concerns the required properties that these materials should have under different environmental conditions, in order to achieve optimal energy savings. Another issue concerns the overall evaluation of PCMs, considering sustainability assessment practices, a fact which is often neglected in PCM studies. This work investigates the post-constructive use of different PCM coatings under diverse environmental conditions, as well as for different structural elements. In the context of this work, a validated finite elements numerical model is utilized, as well as Life Cycle Assessment practices, for the holistic determination of the optimal application conditions of PCM coatings. The work examines the application of PCM coatings in 8 different structural elements, for diverse meteorological conditions in Europe, for all major buildings’ orientations. Life Cycle Assessment is also employed to determine the overall environmental performance of the investigated structural elements. In certain cases, the study revealed that PCM implementation can contribute to energy savings, varying from 0.24 up to 29,84 [kWh/m2a] and energy payback periods from 0.81 to 19.40 years. The purpose of this study is to provide informed answers with regard to the post-constructive application of PCM in existing structures for the energy upgrade of buildings.

Experimental and thermodynamic analysis of solar air dryer equipped with V-groove double pass collector: Techno-economic and exergetic measures

• Thermodynamic model and experimental validation of v-groove solar dryer. • Optimum flow rate of air within the collector was obtained for maximum efficiency. • SEC was 3.01 kWh/kg at 0.041 kg/s with 59% energy saving for apple drying compared with electricity driven heating. • Sustainability indices of the solar air collector and dryer are 1.50 and 1.047 respectively. • Energy payback period for the system is less than 1 year. Optimised solar air dryers, in terms of efficiency and performance, can solve some major concerns in the agro-industrial processing sector. Solar air dryers can reduce the large share of energy costs of a final product and can provide sustainable energy in rural areas where access to energy is often limited. In this study, a pilot scale v-groove double pass solar air collector has been analysed thermodynamically with real time solar radiation and mass flow rate (0.021-0.061 kg/s) inputs and validated experimentally in terms of first and second law efficiencies. Performance of the process was assessed using experimental drying measures including final moisture content, drying rate and exergy efficiency for drying of Pink Lady apples. Energy payback time and specific energy consumption were calculated to reveal the techno-economic value of the system. The maximum thermal efficiency of the collector was observed to be 88.8% at 0.061 kg/s having exergy efficiency of 6.6% which shows an efficient sourcing for the operation. In terms of the performance of the dryer, mass flow rate of 0.041 kg/s offers a higher moisture removal. Specific energy consumption (SEC) was 3.096 kWh/kg. Thermodynamic model was validated with matching experimentation with acceptable RMSE for the range of investigated measures. Energy payback period time calculated by the embodied energy of the system was obtained to be 0.78 years which implies that the system is capable of addressing a large capacity drying if it is to be scaled-up.

Impact of air barriers application in LCA and LCC of naturally ventilated dwellings in mild climate regions

Assessing singular elements that constitute the air barrier of a building envelope is quite unfeasible in Life Cycle Assessment (LCA). The study of these solutions through this particular scope is often overlooked. Two major aspects contribute to it: the complexity of the relationships between elements and the reduced embodied impact of these materials in the overall construction or retrofitting works. This work uses LCA and Life Cycle Costing (LCC) to study the viability of applying two envelope air barrier solutions in dwellings with excessive air change rates and equipped with different heating systems. The application of air barrier solutions resulted in average energy consumption savings in urban terrain, almost half of those in rural terrain during the heating season. Environmental performance and life cycle costs revealed mechanically (MECH) fastened air barriers to outperform fluid (FLUID) applied ones. The median annualized cost of adopting a FLUID solution was almost four times that of a MECH solution. Dwellings equipped with electric radiators ranked first in the shortest average Energy Payback Period (EPP) and the highest average Reference Service Life (RSL) savings. With the current analysis, the adoption of MECH solutions is recommended, independently of the heating system the dwelling is equipped with.

Exergoeconomic and environmental impact evaluation of wind energy assisted hybrid solar dryer and conventional solar dryer

Exergoeconomic analysis is one of the basic methods that clearly reveal the energy cost analysis of a system. The analysis of environmental impact, on the other hand, is the based factor that detects energy payback time and CO2 reduction according to the amount of energy contained in a system. In this study, a wind energy assisted hybrid solar dryer (WASD) was developed, tested in both simple conventional solar dryer (CSD) and WASD modes, and exergoeconomic and environmental impact assessments were examined for these two modes. While the required electrical energy for the WASD mode was obtained from the wind energy, on the other hand, the necessary electrical energy for the CSD mode was required from the grid electricity. According to the exergoeconomic analysis results, it was detected that the fan was the basic component that needed improvement in both situations. With respect to the environmental impact analysis, the energy payback periods for WASD and CSD modes were determined as 1.36 and 0.62 years, respectively. Moreover, the data obtained revealed that the WASD mode was approximately 50% more advantageous in terms of energy and drying efficiency compared to the CSD mode.

Investigation of exergy-energy and environ-economic performance parameters of active indirect solar dryer for pineapple drying without and with energy storage unit

The quality, quantity and availability of energy, the environmental impact, and the economic importance (4E) of a forced convection indirect solar dryer without (setup-1) and with thermal energy storage (TES) system (setup-2) were analyzed during the drying pineapple. Once the tests were finished in setup-1, setup-2 was adopted by integrating with a system having paraffin as a TES unit. The temperature, velocity, and mass data were recorded to evaluate the 4E parameters. The collector and drying efficiency for setup-1 and setup-2 were 67.04, 66.97 % and 7.23, 10.84 %, respectively. Setup-2 was better in activation energy and specific energy consumption. The average exergy efficiency of collector and dryer for setup-1 and setup-2 were 2.33 and 2.12 % and 34.66 and 57.07 %, respectively. Other exergy parameters like inflow, outflow, and loss for collector and dryer and sustainability indicators like waste energy ratio, improvement potential, the environmental impact factor, and sustainability index were enhanced in setup-2. CO2 emission, mitigation, and credit were improved in setup-2. The energy payback period for setup-1 and setup-2 was 1.503 and 1.831 years, while the corresponding economic payback period was 1.41 and 0.93 years in 35 years, respectively. Setup-2 performed better than setup-1 based on the estimated parameters.

Application of concatenated stepped solar still system (CS4) for RO-waste-water purification: an experimental study.

This experimental study investigates the capability of a concatenated stepped solar still system (CS4) for RO-waste-water purification by assessing its thermo-enviro-economic aspects. In order to confirm the supremacy of CS4, a simple stepped solar still system (S5) of equivalent basin area (0.75 m2) is fabricated and tested. The experiments are conducted on CS4 and S5 simultaneously at different flow rates for comparison. The productivity of CS4 is observed to be 24.7 % higher than that of S5; thus, its pollutant removal efficiency is better. As compared to S5, CS4 is found to be more sustainable, economical, and better in terms of distillate production and thermal and exergy efficiencies which are optimum at 50 ml/min. The distillate production, thermal efficiency, and exergy efficiency of CS4 at 50 ml/min flow of RO-waste-water are 2.8 kg/day, 33.80%, and 1.93%, respectively. The second and third units in CS4 work in active mode that increases the solar energy utilization by 34.19% at optimal flow rate. The CO2 mitigation capability of CS4 is 8.89 tons and its distillate production cost is $0.021. At optimum flow rate, its energy and economic payback periods are evaluated as 199 and 483 days, respectively.

Life Cycle Assessment of Wind Turbine in Turkey

This article aims to assess life cycle analysis of a wind turbine in Turkey regarding production, transport, construction, operation, and disposal processes in terms of energy and environment. In this context, a 2-MW three-bladed horizontal axis wind turbine has been selected. Two different scenarios have been studied which comprises wind turbines using Al-Conductor and Cu-Conductor cables. Although the cost of Al-Conductor cables is low, their joule losses are higher. The life cycle assessment of a wind turbine includes production, transportation, construction, operation and disposal, and the energy has been generated in its operation time (selected as 20 years). Iron, cast iron, steel, copper, aluminum, and oil have been sent to a recycling facility and the composite materials has been sent for incineration at the end of its life. The energy payback period has been calculated as 10 months in both scenarios and the embodied energy is 2858.2 MWh and 2830.3 MWh for wind turbine using Al-Conductor and Cu-Conductor cable during its lifetime, respectively. Air emission and wastewater production have been calculated to assess environmental impacts (global warming, acidification, eutrophication, etc.) whose consequence provides an evaluation of the life cycle assessment of a wind turbine. For example, global warming is 14.44 and 15.24 g CO2 eq./kWh for wind turbine using Al-Conductor and Cu-Conductor cable, respectively. As a result, the life cycle analysis of the wind turbines has been evaluated and compared regarding two different scenarios according to the definition of ISO 14040 standard throughout its life from production to disposal.

Energy, exergy, economic and environmental (4E) assessments of a tea withering trough coupled with a solar air heater having an absorber plate with Al-can protrusions

Green tea leaves are dried partially at low temperatures (withered) after harvest. The present study evaluated the energy, exergy, economic and environmental aspects of a solar energy based laboratory-scaled tea withering trough. The trough was coupled with a solar air heater having an absorber plate protruded with waste Al-cans. The temperature within the trough was maintained around 35 °C. The airflow rates considered were 0.03, 0.04 and 0.05 kg/s. The maximum thermal efficiencies computed for the SAH for these mass flow rates were 52.58% at solar radiation of 747 W/m2, 63.65% at 760 W/m2 and 59.25% at 753 W/m2. The exergy efficiencies of the SAH and the withering trough were obtained within (1.41–3.56)%, (1.59–4.51)%, (1.33–4.24)%, and (32.36–72.69)%, (50.59–91.16)%, (37.50–85.62)% respectively. The economic and energy payback periods of the withering trough were computed as 0.90 and 1.26 years. The carbon credit earned was estimated within (145.25–581)$ for a lifetime of 20 years.

Hybrid Model of Solar and Wind Energy for Powering Street Lights: Feasibility Study

Sultanate of Oman is targeting to implement renewable energy sources thirty percent of total energy sources within 2030. In line with the strategic plan, the hybrid model of solar and wind energy based highway lights is proposed on the Muscat highway. An attempt will be made to utilize the wind energy being generated through the movement of vehicles on the highway to change it to electrical energy to power the highway lights. Since the amount of electricity generated depends on the vehicle speed, wind direction, velocity and the placement of vertical axis wind turbines on the highway. In order to overcome the fluctuation of electricity generation, a hybrid model of solar and wind energy is proposed.to generate the maximum required electricity and provide continuous supply. As a first step in this research, the techno economic analysis has been carried out to evaluate the performance parameters such as energy production, capital expenditure, payback period and return of investment. As per the analytical model the payback period is approximately 3.2 years and the return of the investment of 221% are expected over the 10 year period The proposed next step in the research is to install hybrid model of PV solar cells and VAWTs on the median of the Muscat highways between As Seeb and Al Ruwi to see the potential to augment the electricity generation from the vehicle induced turbulence on the natural wind.

A novel combination of absorption heat transformer and refrigeration for cogenerating cooling and distilled water: Thermoeconomic optimization

A novel cogeneration system consisting of an absorption heat transformer and refrigeration system integrated with a water desalination system is proposed, analyzed, and optimized. The cogeneration and desalination systems interacted thermally. The proposed system is flexible in producing cooling and distilled water with variable fractions. Influences on system performance are investigated of the decision parameters. A maximum value of 39 °C is achieved for gross temperature lift. Also, it is observed that the condenser temperature, which is influenced by climate conditions, affects system performance. The system performance is optimized considering such criteria as exergy efficiency, the rate of distilled water production, and total product unit cost. Depending on the criteria used for optimization, the results indicate a minimum total product unit cost of 42.6$/GJ, a maximum exergy efficiency of 27.9%, and a maximum distilled water mass flow rate of 0.53 kg/s. The minimum total capital cost rate and exergy destruction cost rate are found to be 11 $/h and 3.89 $/h, respectively. Under optimized conditions, the generator is seen to contribute the most to the total exergy destruction rate. The values of levelized cost of energy and water and payback period are 0.013 $/kWh, 9 $/m3 and 1.8 year, respectively.

Energy-exergy and environ-economic (4E) analysis while drying ivy gourd in a passive indirect solar dryer without and with energy storage system and results comparison

The energy-exergy and environ-economic (4E) analysis was conducted while drying ivy gourd in a natural convection indirect solar dryer (ISD) without and with a thermal energy storage system (TESS). The initial setup was modified with TESS by integrating a rectangular glass box holding polycarbonate tubes filled with paraffin wax. The paraffin wax was selected based on its easy availability in the market, and also the existing studies suggested that it works successfully by shortening the drying time, homogenizing the process and maintaining temperature. Mass loss, air velocity, and temperature data were recorded during experiments in both setups. The average collector and drying efficiencies of ISD were 62.56 and 61.87 (without and with TESS) and 6.62% and 13.13% (without and with TESS), respectively. The specific energy consumptions were 1.549 and 0.253 kWh/kg for without and with TESS, respectively. The exergy parameters for collector and drying cabinet such as average exergy efficiency, loss, outflow, and inflow without and with TESS were estimated. Other exergy parameters such as the ratio of waste exergy, improvement potential, sustainability index and environmental impact factor were estimated and compared for both setups. CO2 mitigation and credit were better with the TESS setup. The energy payback period of the dryer was 1.04 and 1.51 years for without and with TESS setups for a lifespan of 25 years. Comparatively, with TESS setup performed well in all the evaluated parameters.

Energy, exergy, economic and environmental (4E) analysis of passive and active-modes indirect type solar dryers while drying guava slices

The present study investigated the energy, exergy, economic and environmental (4E) analysis of passive and active mode indirect solar dryers (PMISD and AMISD) while drying guava slices in Warangal, India. The AMISD was developed by attaching a divergent duct with PMISD which consist of DC fans powered by PV panels at the entrance of the collector. The energy analysis revealed that average collector efficiency, drying efficiency and energy utilization ratio were 56.05, 5.42 and 13.27% and 65.37, 6.84 and 10.57% in PMISD and AMISD, respectively. The exergy efficiencies of the collector and drying chamber were 3.74 and 50.92% and, 2.39% and 57.03% in PMISD and AMISD, respectively. The economic analysis revealed that the payback period was noticed to be 2.24 and 1.38 years for PMISD and AMISD, respectively. The energy payback periods of PMISD and AMISD are 1.01 and 1.5 years, respectively. The CO2 emission, CO2 mitigation and maximum carbon credit earned for both the dryers were estimated at a lifetime of 35 years. The 4E analysis concluded that the performance of AMISD is higher compared to PMISD and both ISDs are economically viable and sustainable with a lower impact on the environment.

Techno-enviro-exergo-economic and water hygiene assessment of non-cover box solar still employing parabolic dish concentrator and thermoelectric peltier effect

This study was conducted to design a parabolic dish concentrator box solar still without a glass cover combined with a thermoelectric condensing duct. The parabolic set reflects the sun's rays beneath the basin and the vapor generated in the basin is sucked by a fan with variable volume flow rate into the condensing duct, which is surrounded by four thermoelectrics cooling modules. The performance of non-cover box solar still with thermoelectric is reported based on the component temperature, distilled water production, energy, exergy, energy payback period, energy production factor, economic, exergoeconomic, environmental, enviroeconomic, exergoenvironmental, exergoenviroeconomic, and water hygiene assessment. In the optimal case, in which the fan sucks the vapor at a volume rate of 300 L/min, the average winter daily cumulative distilled water, energy efficiency, and exergy efficiency were enhanced by 25.6%, 4.88%, and 1.06%, respectively, compared to the case, which the fan is off. The cost of distilled water production and the payback period in the optimal case are 0.0056 $/L/m2 and 114 days, respectively. Also, the techno-enviro-exergo-economic findings revealed that the parabolic dish concentrator box solar still with thermoelectric in terms of enviroeconomic and exergoenviroeconomic can create a financial reserve of $320.02 and $50.32, respectively. The distilled water produced by the desalination system is safe in terms of hygiene and drinking ability.

Evaluating the Effectiveness of Energy-Saving Retrofit Strategies for Residential Buildings

Most of the apartment buildings in the Republic of Kazakhstan were built more than 40 years ago. The buildings were designed according to traditional approaches and are the main consumers of thermal energy. The work aims to study various energy-efficient options for modernizing residential buildings and to quantify the actual energy savings and payback period. The paper presents the results of monitoring the energy efficiency of apartment buildings for the period before and after repairs. The results of assessing five thermo-modernization options showed that mineral wool insulation (more than 0.15 m thick) of external walls and roofs saves more than 30 Gcal/year of heat energy. Installation of double-glazed windows with insulating vinyl frame and insulating front doors saves up to 3 Gcal/year of heat energy. It was found that heat recovery ventilation with good thermal tightness of a building can reduce the consumed heat up to 21 Gcal/year. According to the results of the energy audit of the studied buildings, the best modernization options (which increase buildings' energy efficiency 3 times) were selected. A comparative analysis of calculated and actual data on Energy Consumption (EC) after buildings' renovation showed a difference of 10%. The most effective and economical method of apartment buildings' modernization with heat energy consumption of about 0.05 Gcal/m² per year was determined. The results obtained can be used in the passport of buildings and for future research in the field of housing architecture modernization.

Development of a New Residential Energy Management Approach for Retrofit and Transition, Based on Hybrid Energy Sources

The building sector contributes to a significant part of growing global energy demand. Improving the energy efficiency of the existing building stock is a crucial strategy. Adopting the best energy retrofit strategy in a specific building is a hard task due to the multitude of possible combinations of retrofit measures and the management of different renewable energy sources in the building. However, significant efforts must be made to combine envelope retrofit with renewable energy to improve the energy efficiency of existing buildings and minimize the energy payback period and greenhouse gas (GHG) emissions. It also helps to achieve a successful transition to zero fossil fuel energy for houses and an existing housing stock free of greenhouse gas emissions. This paper is based on a systematic approach, which was applied to an Algerian case study “high-rise building/housing units” that represented southern Mediterranean countries. The percentage of energy consumption was identified; moreover, the performance of on-site hybrid exploitation of renewable energy systems such as photovoltaic cells, thermodynamic panels and small wind turbines was proven. Several actors have collaborated and a range of software types have been used (3D modelling, meteorological regeneration data, energy simulation of buildings, estimation of renewable energy production and statistical analysis). As a result, the building case study has become more efficient than before, whereas the payback time was 10 years. The economic and environmental analysis highlighted that it is possible to save energy demand by up to 51–75% for heating and up to 5–32% for cooling; electricity and hot water consumption was covered at 98% and 80%, respectively, whereas associated gas emissions are reduced by up to 252 tons per building, a reduction of 91%. The model of the platform designed is multi-disciplinary, facilitating collaboration with the various stakeholders to identify directions for successful interventions in pre-established cities. It is a solid framework for future research aimed at standardizing the approach to energy retrofitting and transitioning in existing buildings and is suitable for all types of residential buildings of the southern Mediterranean region such as Algeria, Tunisia and Morocco.

Sustainability and performance analysis of a solar and wind energy assisted hybrid dryer

In this study, energy, exergy and sustainability analysis of the solar and wind energy assisted hybrid drying system were discussed. The drying process was carried out by solar dryer. Wind energy was used to provide the electrical energy required for the operation of the fan in the drying unit. So, no external energy source was required for the drying process. The main purpose of the study was to contribute to the development of an economical and environmentally friendly drying system that was operated using only two different renewable energy sources. The drying characteristics of banana slices were determined in the experiments. It was found that the exergy efficiency of the dryer was in the range of 68.04–83.89%, as a result of the experiments. The system was also examined in terms of waste exergy rate, improvement potential and environmental sustainability. The evaluations showed that the hybrid dryer had 57.7% and 21.52% higher exergy efficiency compared to other conventional solar dryers and solar assisted- hybrid dryers, respectively. Moreover, the energy payback period was determined as 1.36 years. This result clearly indicated that the system can recover the energy it consumed in approximately 38.18% shorter time compared to other solar dryers.