scholarly journals An Innovative Solar-Biomass Energy System to Increase the Share of Renewables in Office Buildings

Energies ◽  
2021 ◽  
Vol 14 (4) ◽  
pp. 914
Author(s):  
Valeria Palomba ◽  
Emiliano Borri ◽  
Antonios Charalampidis ◽  
Andrea Frazzica ◽  
Sotirios Karellas ◽  
...  
Keyword(s):  
Energy Demand ◽  
Residential Buildings ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Energy System ◽  
Hot Water ◽  
Biomass Energy ◽  
Office Buildings ◽  
Adsorption Chiller ◽  
Intervention Measures

Increasing the energy efficiency of residential and non-residential buildings is a crucial point towards the development of the sustainable cities of the future. To reach such a goal, the commonly employed intervention measures (for instance, on facades and glass) are not sufficient and efforts in reaching a fully renewable energy generation are mandatory. In this context, this paper discusses the applicability of a system with solar and biomass as the main energy sources in different climates for heating, cooling, domestic hot water and electricity generation in office buildings. The energy system includes solar thermal collectors with thermoelectric generators, a biomass boiler, a reversible heat pump/organic Rankine cycle and an adsorption chiller. The results showed that the system can operate with a share of renewables higher than 70% for all energy needs, with up to 80% of the overall energy demand supplied only by solar and biomass sources even in the northern locations.

Thermodynamic and Performance Study of Solar Regenerative Organic Rankine Cycle System for Use in Residential Micro-Combined Heat and Power Generation

2019 ◽  
Author(s):  
Wahiba Yaïci ◽  
Evgueniy Entchev
Keyword(s):  
Power Generation ◽  
Energy Demand ◽  
Waste Heat ◽  
Residential Buildings ◽  
Electrical Power ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Combined Heat And Power ◽  
Energy Sources ◽  
Performance Study

Abstract A continued increase in both energy demand and greenhouse gas emissions (GHGs) call for utilising energy sources effectively. In comparison with traditional energy set-ups, micro-combined heat and power (micro-CHP) generation is viewed as an effective alternative; the aforementioned system’s definite electrical and thermal generation may be attributed to an augmented energy efficiency, decreased capacity as well as GHGs percentage. In this regard, organic Rankine cycle (ORC) has gained increasing recognition as a system, which is capable for generating electrical power from solar-based, waste heat, or thermal energy sources of a lower quality, for instance, below 120 °C. This study focuses on investigating a solar-based micro-CHP system’s performance for use in residential buildings through utilising a regenerative ORC. The analysis will focus on modelling and simulation as well as optimisation of operating condition of several working fluids (WFs) in ORC in order to use a heat source with low-temperature derived from solar thermal collectors for both heat and power generation. A parametric study has been carried out in detail for analysing the effects of different WFs at varying temperatures and flowrates from hot and cold sources on system performance. Significant changes were revealed in the study’s outcomes regarding performance including efficiency as well as power obtained from the expander and generator, taking into account the different temperatures of hot and cold sources for each WF. Work extraction carried out by the expander and electrical power had a range suitable for residential building applications; this range was 0.5–5 kWe with up to 60% electrical isentropic efficiency and up to 8% cycle efficiency for 50–120 °C temperature from a hot source. The operation of WFs will occur in the hot source temperature range, allowing the usage of either solar flat plate or evacuated tube collectors.

scholarly journals The study of a seasonal solar CCHP system based on evacuated flat-plate collectors and organic Rankine cycle

2020 ◽  
Vol 24 (2 Part A) ◽  
pp. 915-924
Author(s):  
Guangtao Gao ◽  
Jing Li ◽  
Jingyu Cao ◽  
Honglun Yang ◽  
Gang Pei ◽  
...  
Keyword(s):  
Flat Plate ◽  
Thermal Efficiency ◽  
Residential Buildings ◽  
Lithium Bromide ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Hot Water ◽  
Outlet Temperature ◽  
Average Output ◽  
Autumn And Winter

The demands of cooling, heating and electricity in residential buildings are varied with seasons. This article presented a seasonal solar combined cooling heating and power (CCHP) system based on evacuated flat-plate collectors and organic Rankine cycle. The heat collected by evacuated flat-plate collectors is used to drive the organic Rankine cycle unit in spring, autumn and winter, and drive the double-effect lithium bromide absorption chiller in summer. The organic Rankine cycle condensation heat is used to yield hot water in spring and autumn, whereas supply heating in winter. The system thermodynamic performance was analyzed. The results show that the system thermal efficiency in spring, autumn and winter, ?sys,I, increases as organic Rankine cycle evaporation temperature, T6, and evacuated flat-plate collectors outlet temperature, T2, decrease. The maximum ?sys,I of 67.0% is achieved when T6 = 80?C and T2 =100?C. In summer, the system thermal efficiency, ?sys,II, increases first and then decreases with the increment of T2. The maximum ?sys,II of 69.9% is obtained at T2 =136?C. The system output performance in Beijing and Lanzhou is better than that in Hefei. The average output power, heating capacity, hot water and cooling capacity are 50-72 kWh per day, 989-1514 kWh per day, 49-57 ton per day and 1812-2311 kWh per day, respectively. The system exergy efficiency increases from 17.8-40.8% after integrating the organic Rankine cycle unit.

scholarly journals Multi-Country Analysis on Energy Savings in Buildings by Means of a Micro-Solar Organic Rankine Cycle System: A Simulation Study

Environments ◽  
2018 ◽  
Vol 5 (11) ◽  
pp. 119 ◽  
Author(s):  
Alessia Arteconi ◽  
Luca Del Zotto ◽  
Roberto Tascioni ◽  
Khamid Mahkamov ◽  
Chris Underwood ◽  
...  
Keyword(s):  
Thermal Energy ◽  
Energy Demand ◽  
Energy Use ◽  
Energy Savings ◽  
Organic Rankine Cycle ◽  
Cost Savings ◽  
Rankine Cycle ◽  
Primary Energy ◽  
Operational Cost ◽  
The North

In this paper, the smart management of buildings energy use by means of an innovative renewable micro-cogeneration system is investigated. The system consists of a concentrated linear Fresnel reflectors solar field coupled with a phase change material thermal energy storage tank and a 2 kWe/18 kWth organic Rankine cycle (ORC) system. The microsolar ORC was designed to supply both electricity and thermal energy demand to residential dwellings to reduce their primary energy use. In this analysis, the achievable energy and operational cost savings through the proposed plant with respect to traditional technologies (i.e., condensing boilers and electricity grid) were assessed by means of simulations. The influence of the climate and latitude of the installation was taken into account to assess the performance and the potential of such system across Europe and specifically in Spain, Italy, France, Germany, U.K., and Sweden. Results show that the proposed plant can satisfy about 80% of the overall energy demand of a 100 m2 dwelling in southern Europe, while the energy demand coverage drops to 34% in the worst scenario in northern Europe. The corresponding operational cost savings amount to 87% for a dwelling in the south and at 33% for one in the north.

scholarly journals Experimental investigation of domestic micro-CHP based on the gas boiler fitted with ORC module

2016 ◽  
Vol 37 (3) ◽  
pp. 79-93 ◽  
Author(s):  
Jan Wajs ◽  
Dariusz Mikielewicz ◽  
Michał Bajor ◽  
Zbigniew Kneba
Keyword(s):  
Energy Demand ◽  
Electricity Generation ◽  
Electric Energy ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Future Generation ◽  
Working Fluid ◽  
Ethanol Vapour ◽  
System User ◽  
Generation Unit

AbstractThe results of investigations conducted on the prototype of vapour driven micro-CHP unit integrated with a gas boiler are presented. The system enables cogeneration of heat and electric energy to cover the energy demand of a household. The idea of such system is to produce electricity for own demand or for selling it to the electric grid – in such situation the system user will became the prosumer. A typical commercial gas boiler, additionally equipped with an organic Rankine cycle (ORC) module based on environmentally acceptable working fluid can be regarded as future generation unit. In the paper the prototype of innovative domestic cogenerative ORC system, consisting of a conventional gas boiler and a small size axial vapour microturbines (in-house designed for ORC and the commercially available for Rankine cycle (RC)), evaporator and condenser were scrutinised. In the course of study the fluid working temperatures, rates of heat, electricity generation and efficiency of the whole system were obtained. The tested system could produce electricity in the amount of 1 kWe. Some preliminary tests were started with water as working fluid and the results for that case are also presented. The investigations showed that domestic gas boiler was able to provide the saturated/superheated ethanol vapour (in the ORC system) and steam (in the RC system) as working fluids.

Numerical Study of a Micro Gas Turbine Integrated With a Supercritical CO2 Brayton Cycle Turbine

2018 ◽  
Author(s):  
Fabrizio Reale ◽  
Vincenzo Iannotta ◽  
Raffaele Tuccillo
Keyword(s):  
Gas Turbines ◽  
Waste Heat ◽  
Numerical Study ◽  
Organic Rankine Cycle ◽  
Energy Systems ◽  
Rankine Cycle ◽  
Energy System ◽  
Small Scale ◽  
Brayton Cycle ◽  
Integrated Energy System

The primary need of reducing pollutant and greenhouse gas emissions has led to new energy scenarios. The interest of research community is mainly focused on the development of energy systems based on renewable resources and energy storage systems and smart energy grids. In the latter case small scale energy systems can become of interest as nodes of distributed energy systems. In this context micro gas turbines (MGT) can play a key role thanks to their flexibility and a strategy to increase their overall efficiency is to integrate gas turbines with a bottoming cycle. In this paper the authors analyze the possibility to integrate a MGT with a super critical CO2 Brayton cycle turbine (sCO2 GT) as a bottoming cycle (BC). A 0D thermodynamic analysis is used to highlight opportunities and critical aspects also by a comparison with another integrated energy system in which the waste heat recovery (WHR) is obtained by the adoption of an organic Rankine cycle (ORC). While ORC is widely used in case of middle and low temperature of the heat source, s-CO2 BC is a new method in this field of application. One of the aim of the analysis is to verify if this choice can be comparable with ORC for this operative range, with a medium-low value of exhaust gases and very small power values. The studied MGT is a Turbec T100P.

Meanline Analysis and CFD Study of a Radial Inflow Turbine With Vaneless Distributor for Low Temperature Organic Rankine Cycle

2020 ◽  
Author(s):  
M. Deligant ◽  
S. Braccio ◽  
T. Capurso ◽  
F. Fornarelli ◽  
M. Torresi ◽  
...  
Keyword(s):  
Energy Demand ◽  
Waste Heat ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Operating Conditions ◽  
Low Grade ◽  
Heat Sources ◽  
Turbine Wheel ◽  
Good Efficiency ◽  
Low Grade Heat

Abstract The Organic Rankine Cycle (ORC) allows the conversion of low-grade heat sources into electricity. Although this technology is not new, the increase in energy demand and the need to reduce CO2 emissions create new opportunities to harvest low grade heat sources such as waste heat. Radial turbines have a simple construction, they are robust and they are not very sensitive to geometry inaccuracies. Most of the radial inflow turbines used for ORC application feature a vaned nozzle ensuring the appropriate distribution angle at the rotor inlet. In this work, no nozzle is considered but only the vaneless gap (distributor). This configuration, without any vaned nozzle, is supposed to be more flexible under varying operating conditions with respect to fixed vanes and to maintain a good efficiency at off-design. This paper presents a performance analysis carried out by means of two approaches: a combination of meanline loss models enhanced with real gas fluid properties and 3D CFD computations, taking into account the entire turbomachine including the scroll housing, the vaneless gap, the turbine wheel and the axial discharge pipe. A detailed analysis of the flow field through the turbomachine is carried out, both under design and off design conditions, with a particular focus on the entropy field in order to evaluate the loss distribution between the scroll housing, the vaneless gap and the turbine wheel.

scholarly journals Experimental Investigation on Performance of an Organic Rankine Cycle System Integrated with a Radial Flow Turbine

Energies ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 724 ◽  
Author(s):  
Lisheng Pan ◽  
Huaixin Wang
Keyword(s):  
Radial Flow ◽  
Cooling Water ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Hot Water ◽  
Outlet Temperature ◽  
Generation Efficiency ◽  
Operation Parameters ◽  
Condensing Pressure ◽  
Isentropic Efficiency

An experimental method is used to investigate the performance of a small-scale organic Rankine cycle (ORC) system which is integrated with a radial flow turbine, using 90 °C hot water as a heat source. The considered working fluids are R245fa and R123. The relationship between cycle performance and the operation parameters is obtained. With constant condensing pressure (temperature), the outlet temperature of the hot water, the mass flow rate of the hot water and the evaporator heat transfer rate increase with increasing evaporating pressure. Turbine isentropic efficiency decreases and transmission-generation efficiency increases with rising evaporating pressure. In the considered conditions, the maximum specific energy is 1.28 kJ/kg, with optimal fluid of R245fa and an optimal evaporating temperature of 69.2 °C. When the evaporating pressure (temperature) is constant, the outlet temperature of the cooling water increases, and the mass flow rate of the cooling water decreases with increasing condensing pressure. Turbine isentropic efficiency increases and transmission-generation efficiency decreases with the rise of condensing pressure. In the considered conditions, the maximum specific energy is 0.89 kJ/kg, with optimal fluid of R245fa and an optimal condensing temperature of 29.1 °C. Turbine efficiency is impacted by the working fluid type, operation parameters and nozzle type.

scholarly journals Matching Energy Consumption and Photovoltaic Production in a Retrofitted Dwelling in Subtropical Climate without a Backup System

Energies ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 6026
Author(s):  
Sergio Gómez Melgar ◽  
Antonio Sánchez Cordero ◽  
Marta Videras Rodríguez ◽  
José Manuel Andújar Márquez
Keyword(s):  
Renewable Energy ◽  
Energy Demand ◽  
Energy Production ◽  
Residential Buildings ◽  
Hot Water ◽  
Subtropical Climate ◽  
Zero Energy ◽  
Electric Circuits ◽  
Renewable Energy Production ◽  
Zero Energy Buildings

The construction sector is a great contributor to global warming both in new and existing buildings. Minimum energy buildings (MEBs) demand as little energy as possible, with an optimized architectural design, which includes passive solutions. In addition, these buildings consume as low energy as possible introducing efficient facilities. Finally, they produce renewable energy on-site to become zero energy buildings (ZEBs) or even plus zero energy buildings (+ZEB). In this paper, a deep analysis of the energy use and renewable energy production of a social dwelling was carried out based on data measurements. Unfortunately, in residential buildings, most renewable energy production occurs at a different time than energy demand. Furthermore, energy storage batteries for these facilities are expensive and require significant maintenance. The present research proposes a strategy, which involves rescheduling energy demand by changing the habits of the occupants in terms of domestic hot water (DHW) consumption, cooking, and washing. Rescheduling these three electric circuits increases the usability of the renewable energy produced on-site, reducing the misused energy from 52.84% to 25.14%, as well as decreasing electricity costs by 58.46%.

scholarly journals A Hot Water Split-Flow Dual-Pressure Strategy to Improve System Performance for Organic Rankine Cycle

Energies ◽  
2020 ◽  
Vol 13 (13) ◽  
pp. 3345 ◽  
Author(s):  
Shiqi Wang ◽  
Zhongyuan Yuan
Keyword(s):  
Output Power ◽  
Thermal Energy ◽  
System Performance ◽  
Industrial Waste ◽  
Organic Rankine Cycle ◽  
Rankine Cycle ◽  
Hot Water ◽  
Inlet Temperature ◽  
Split Flow ◽  
Net Power Output

The organic Rankine cycle (ORC) is widely used to recover industrial waste heat. For an ORC system using industrial waste hot water as a heat source, a novel hot water split-flow dual-pressure organic Rankine cycle (SFD-ORC) system is developed to improve the performance of the ORC. The maximum net power output was selected to compare three ORC systems, including basic ORC (B-ORC), conventional dual-pressure ORC (CD-ORC) and SFD-ORC. A genetic algorithm (GA) was used to optimize the parameters to search the maximum net power output of ORCs. The maximum net output power was taken as the standard of performance evaluation. The results show that, under the same hot water inlet temperature condition, the optimal hot water outlet temperature of B-ORC is much higher than that of CD-ORC and SFD-ORC, which indicates that less thermal energy could be utilized to convert to power in B-ORC. The optimal hot water temperature at the outlet of evaporator 1 in SFD-ORC is higher than that in CD-ORC, which means SFD-ORC could make more efficient use of the high-grade thermal energy of hot water. The SFD-ORC could obtain the highest net output power under the optimal parameter conditions, followed by the CD-ORC system, while the B-ORC has the lowest net output power. Moreover, with the increase in the hot water inlet temperature, the advantage of SFD-ORC becomes increasingly obvious. When the hot water inlet temperature is 90 °C, the net output power of SFD-ORC at is 6.22% higher than that of CD-ORC. The net output power of SFD-ORC at 130 °C increases to 9.7% higher than that of CD-ORC. The SFD-ORC presents better system performance and has great engineering application potential.

Sign in / Sign up

Export Citation Format

Share Document