scholarly journals Back Analysis of a Horizontal Geothermal Plant Implemented in a Wine Production Process

2021 ◽  
Vol 14 (1) ◽  
pp. 157
Author(s):  
Claudio Alimonti ◽  
Gabriele Pecci
Keyword(s):  
Peak Power ◽  
Back Analysis ◽  
Thermal Response ◽  
Primary Energy ◽  
Green Energy ◽  
Operating Conditions ◽  
Wine Production ◽  
Energy Technologies ◽  
Refrigeration Unit ◽  
Geothermal Plant

The Salcheto winery has undertaken a process of reduction of its primary energy consumption and the implementation of green energy technologies. They adopted solar photovoltaic, wood biomass, and geothermal energy sources. A horizontal ground source heat exchanger (GSHE) plant is used to cool a part of the pressed grapes and control the wine production temperature. The goal of this work was to investigate some technical issues of the plant and to increase the efficiency of the whole system. The first step was the evaluation of the actual operating conditions of the GSHE plant, by performing a thermal response test. The results allowed us to find the thermal diffusivity of 3.5 × 10−7 m2/s, and the calculation with the IGSHPA standard indicated a cooling performance of about 6 kW. A survey during the harvest highlighted a peak power of 6 kW. Therefore, to improve the plant, some modifications were proposed and analyzed. In the new layout, the geothermal plant serves the condenser of the refrigeration unit, allowing cooling of the all production lines, instead of only one. The peak power was evaluated as 32 kW, and the GSHE can fulfil this, up to 18 kW. For higher power, the evaporative tower will supply the remainder, covering a maximum of 45%. Furthermore, the refrigeration unit may cover the cooling requirements of the entire residential and office building, without other plant improvements.

Comparison of Wind Tunnel Airfoil Performance Data With Wind Turbine Blade Data

1992 ◽  
Vol 114 (2) ◽  
pp. 119-124 ◽  
Author(s):  
C. P. Butterfield ◽  
George Scott ◽  
Walt Musial
Keyword(s):  
Wind Tunnel ◽  
Wind Turbine ◽  
Peak Power ◽  
Unsteady Aerodynamics ◽  
Leading Edge ◽  
Operating Conditions ◽  
Performance Data ◽  
Horizontal Axis Wind Turbine ◽  
Force Coefficients ◽  
Basic Fluid

Horizontal axis wind turbine (HAWT) performance is usually predicted by using wind tunnel airfoil performance data in a blade element momentum theory analysis. This analysis assumes that the rotating blade airfoils will perform as they do in the wind tunnel. However, when stall-regulated HAWT performance is measured in full-scale operation, it is common to find that peak power levels are significantly greater than those predicted. Pitch-controlled rotors experience predictable peak power levels because they do not rely on stall to regulate peak power. This has led to empirical corrections to the stall predictions. Viterna and Corrigan (1981) proposed the most popular version of this correction. But very little insight has been gained into the basic cause of this discrepancy. The National Renewable Energy Laboratory (NREL), funded by the DOE, has conducted the first phase of an experiment which is focused on understanding the basic fluid mechanics of HAWT aerodynamics. Results to date have shown that unsteady aerodynamics exist during all operating conditions and dynamic stall can exist for high yaw angle operation. Stall hysteresis occurs for even small yaw angles and delayed stall is a very persistent reality in all operating conditions. Delayed stall is indicated by a leading edge suction peak which remains attached through angles of attack (AOA) up to 30 degrees. Wind tunnel results show this peak separating from the leading edge at 18 deg AOA. The effect of this anomaly is to raise normal force coefficients and tangent force coefficients for high AOA. Increased tangent forces will directly affect HAWT performance in high wind speed operation. This report describes pressure distribution data resulting from both wind tunnel and HAWT tests. A method of bins is used to average the HAWT data which is compared to the wind tunnel data. The analysis technique and the test set-up for each test are described.

scholarly journals Calculation algorithm for operating parameters of steam-compressive chilling machine with adsorptive chillling unit

2020 ◽  
Vol 8 (2) ◽  
pp. 3-9
Author(s):  
E.A. Belyanovskaya ◽  
◽  
G.M. Pustovoy ◽  
A.I. Sklyarenko ◽  
M.P. Sukhyy ◽  
...  
Keyword(s):  
Silica Gel ◽  
Thermal Energy ◽  
Sodium Acetate ◽  
Operating Conditions ◽  
Energy Utilization ◽  
Coefficient Of Performance ◽  
Adsorptive Capacity ◽  
Operating Parameters ◽  
Adsorption Refrigeration ◽  
Refrigeration Unit

The work is focused on the development of an effective algorithm for calculating the operational characteristics of a steamcompressive chilling machine with an adsorptive chilling unit, which involves a cold box, an adsorber, an evaporator and a condenser, water being used as a refrigerant. An algorithm for calculating the operating parameters of the adsorptive chilling unit has been developed, which includes the determination of the cooling capacity of the steam compressor refrigeration unit, the heat load on the condenser, the power consumed by the compressor, the coefficient of performance of the steam compressor refrigeration unit, as well as the calculation of the mass of water, the mass of the adsorbent, the refrigerating capacity, the coefficient of performance of the adsorptive chilling unit and the coefficient of useful energy utilization of a steam compressive chilling machine with an adsorption chilling unit. The chilling capacity and the coefficient of performance of the adsorption chilling unit are estimated under the operating conditions of a typical steam compression chilling machine. The crucial factors affecting the efficiency of the adsorptive chilling unit are analyzed. It has been established that the chilling capacity, the coefficient of performance of the adsorption refrigeration module and the energy efficiency of the installation are determined by the thermal load on the condenser, and, therefore, by the mass of water that is desorbed and evaporated. The coefficient of performance of the adsorption chilling unit and the efficiency of the steam compressor chilling machine with the adsorptive chilling unit are estimated to be 0.878 and 4.64. The criteria for the selection of adsorbents for the adsorption module are analyzed. The temperature of regeneration is determined by the temperatures in the condenser, and the limit adsorption affects the mass of the adsorbent and the size of the adsorber. A comparison of the efficiency of adsorptive chi l l ing uni t based on silicoaluminophosphates and composite adsorbents «silica gel – sodium acetate» is carried out. The prospects of using composites «silica gel – СН3СООNa» are shown. The optimal composition of the composite was established, which corresponds to the minimal size of the adsorber, (80% sodium acetate and 20% silica gel). The prospects of using adsorptive conversion of thermal energy for utilization of low-potential thermal energy during the operation of steam compressive chilling machine are shown. Keywords: adsorptive conversion of heat energy, composite adsorbent, steam compressive chilling unit, adsorption, adsorptive capacity.

Examining the barriers and motivators affecting European decision-makers in the development of smart and green energy technologies

2018 ◽  
Vol 198 ◽  
pp. 417-429 ◽  
Author(s):  
Mehmet Efe Biresselioglu ◽  
Marie Nilsen ◽  
Muhittin Hakan Demir ◽  
Jens Røyrvik ◽  
Gitte Koksvik
Keyword(s):  
Green Energy ◽  
Decision Makers ◽  
Energy Technologies ◽  
Barriers And Motivators

3-E Analysis of a Heat Pump Driven by a Micro-Cogenerator

2005 ◽  
Author(s):  
Maurizio Sasso ◽  
Raffaello Possidente ◽  
Carlo Roselli ◽  
Sibilio Sergio
Keyword(s):  
Heat Pump ◽  
Thermal Energy ◽  
Primary Energy ◽  
Operating Conditions ◽  
Environmental Benefits ◽  
Test Facility ◽  
Cooling Mode ◽  
Simplified Approach ◽  
Wide Range ◽  
Network Losses

The cogeneration, or the combined production of electric (and/or mechanical) and thermal energy, is a well established technology, which has important environmental benefits and it has been noted by the European Community as one of the first elements to save primary energy, to avoid network losses and to reduce the greenhouse gas emissions. In particular, the study will be focused on the micro-cogeneration process with micro-combined heat and power system, or MCHP (electric power output ≤ 15 kW), which represents a valid and interesting application of this technology applicable, above all, to residential and light commercial users. This paper presents the Energy, Economic and Environmental (3-E) analysis of a natural gas-fired MCHP in combination with an electric heat pump (EHP). The 3-E analysis of the MCHP/EHP begins with the results of a detailed experimental activity developed in a test facility [1] for a wide range of conditions. Two operating conditions were simulated: a heating mode with co-production of electric and thermal energy, and a cooling mode with co-production of electric, thermal and cooling energy (tri-generation). The annual operating performance, also based on the typical features of the Italian market, is also discussed with a simplified approach.

scholarly journals The globalization of the world coal market – contradictions and trends

2019 ◽  
Vol 123 ◽  
pp. 01044 ◽  
Author(s):  
Yevheniia Sribna ◽  
Olena Trokhymets ◽  
Ihor Nosatov ◽  
Iryna Kriukova
Keyword(s):  
Developed Countries ◽  
World Market ◽  
Coal Industry ◽  
Green Energy ◽  
Energy Technologies ◽  
The World ◽  
The Usa ◽  
Coal Market ◽  
Coal Supply ◽  
State Subsidies

The article describes the global coal market as the ratio of demand and supply depending on the development of energy technologies in the historical section. The continental specificity of coal mining is given. The basic world exporters and importers of coal and their role in the sale of energy fuels are analyzed. The key coal producing countries are China, India, the USA, and Australia. The largest consumers of coal products are China, India, Japan and Korea. There are unconditional leaders in the export coal market: Indonesia and Australia. In addition, a comparison of large coal companies and their share in the world market is presented. The features of coal supplies are analyzed in accordance with international rules (Incoterms), which regulate the rights and obligations of the buyer when conducting international trade, as well as determine the moment of transfer of risks from the seller to the buyer. The following supply bases were characterized: FOB (Free On Board), FAS (Free Alongside Ship), CIF (Cost Insurance and Freight), DAP (Delivered At Place), FCA (Free Carrier) etc. Trends in the logistics component of the global coal industry are revealed. Logistic of coal supply chains in comparison with other energy fuels and their features are disclosed. The problem of profitability of mines and their effectiveness is presented. Assessment of the environmental components of coal use in industry and energy is analyzed. It was noted that on the background of the trend to protect the environment and promote renewable energy, coal is becoming less popular in developed countries. This trend is further exacerbated by state subsidies for green energy.

Green Energy Prospects

2015 ◽  
Vol 6 (3) ◽  
pp. 1-20 ◽  
Author(s):  
S. Filippov ◽  
N. Mikova ◽  
A. Sokolova
Keyword(s):  
International Organizations ◽  
Quantitative Methods ◽  
Technology Development ◽  
Green Energy ◽  
Climate Mitigation ◽  
Scientific Publications ◽  
Qualitative And Quantitative ◽  
Qualitative And Quantitative Methods ◽  
Energy Technologies ◽  
Global Problems

The transition of energy systems moving from non-renewable fossil-nuclear to renewable sources is a key challenge of climate mitigation and sustainable development. Green energy technologies can contribute to solutions of global problems such as climate change, growth of energy consumption, depletion of natural resources, negative environmental impacts, and energy security. In this article the prospective directions of technology development in green energy are studied and analyzed using a combination of qualitative and quantitative methods. Qualitative research involves participation of key experts in the field of green energy, while quantitative analysis includes collecting and processing data from different information sources (scientific publications, patents, news, Foresight projects, conferences, projects of international organizations, dissertations, and presentations) with a help of Vantage Point software. In addition, key challenges for green energy as well as its relationships with other technological and non-technological areas are identified and briefly described on the basis of expert and analytical results.

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