scholarly journals A Numerical Pinch Analysis Methodology for Optimal Sizing of a Centralized Trigeneration System with Variable Energy Demands

Energies ◽  
2020 ◽  
Vol 13 (8) ◽  
pp. 2038 ◽  
Author(s):  
Khairulnadzmi Jamaluddin ◽  
Sharifah Rafidah Wan Alwi ◽  
Khaidzir Hamzah ◽  
Jiří Jaromír Klemeš
Keyword(s):  
Fuel Consumption ◽  
Energy Demand ◽  
Energy System ◽  
Industrial Applications ◽  
Illustrative Case ◽  
Pinch Analysis ◽  
Pressurized Water ◽  
Heating And Cooling ◽  
Energy Demands

The energy and power sectors are critical sectors, especially as energy demands rise every year. Increasing energy demand will lead to an increase in fuel consumption and CO2 emissions. Improving the thermal efficiency of conventional power systems is one way to reduce fuel consumption and carbon emissions. The previous study has developed a new methodology called Trigeneration System Cascade Analysis (TriGenSCA) to optimise the sizing of power, heating, and cooling in a trigeneration system for a Total Site system. However, the method only considered a single period on heating and cooling demands. In industrial applications, there are also batches, apart from continuous plants. The multi-period is added in the analysis to meet the time constraints in batch plants. This paper proposes the development of an optimal trigeneration system based on the Pinch Analysis (PA) methodology by minimizing cooling, heating, and power requirements, taking into account energy variations in the total site energy system. The procedure involves seven steps, which include data extraction, identification of time slices, Problem Table Algorithm, Multiple Utility Problem Table Algorithm, Total Site Problem Table Algorithm, TriGenSCA, and Trigeneration Storage Cascade Table (TriGenSCT). An illustrative case study is constructed by considering the trigeneration Pressurized Water Reactor Nuclear Power Plant (PWR NPP) and four industrial plants in a Total Site system. Based on the case study, the base fuel of the trigeneration PWR NPP requires 14 t of Uranium-235 to an average demand load of 93 GWh/d. The results of trigeneration PWR NPP with and without the integration of the Total Site system is compared and proven that trigeneration PWR NPP with integration is a suitable technology that can save up to 0.2% of the equivalent annual cost and 1.4% of energy compared to trigeneration PWR NPP without integration.

A Case Study of Energy Saving by CCHP Technology in a Hospital

2010 ◽  
Author(s):  
S. Okamoto
Keyword(s):  
Energy Demand ◽  
Energy Savings ◽  
High Efficiency ◽  
Hospital Setting ◽  
Electrical Energy ◽  
Electrical Heating ◽  
Public Network ◽  
Heating And Cooling ◽  
Energy Demands

This paper describes a study that starts with an analysis of typical energy demand profiles in a hospital setting followed by a case study of a CCHP system. The CCHP idea is of an autonomous system for the combined generation of electrical, heating, and cooling energy in a hospital. The driving units are two high-efficiency gas engines that produce the electrical and heat energy. A gas engine meets the requirement for high electrical and heating energy demands; a natural gas-fuelled reciprocating engine is used to generate 735 kW of power. In our case, the electrical energy was used only in the hospital. A deficit in electricity can be covered by purchasing power from the public network. Generated steam drives three steam-fired absorption chillers and is delivered to individual heat consumers. This system can provide simultaneous heating and cooling. No technical obstacles were identified for implementing the CCHP. The typical patterns for driving units of CCHP were decided by the hourly energy demands in several seasons throughout the year. The average ratio between electric and thermal loads in the hospital is suitable for CCHP system operation. An analysis performed for a non-optimized CCHP system predicted a large potential for energy savings and CO2 reduction.

FEASIBILITY ANALYSIS OF A PHOTOVOLTAIC/BATTERY ENERGY STORAGE HYBRID SYSTEM: AN HOURLY ESTIMATION BASED APPROACH AND A REAL LIFE CASE STUDY

2017 ◽  
Vol 12 (3) ◽  
pp. 54-68 ◽  
Author(s):  
Fehmi Görkem Üçtuğ ◽  
Vedat Can Baltalı
Keyword(s):  
Energy Storage ◽  
Energy Demand ◽  
Real Life ◽  
Electricity Consumption ◽  
System Size ◽  
Battery Energy Storage ◽  
Heating And Cooling ◽  
Weather Changes ◽  
Battery Energy

This study has been undertaken to develop a consumer-oriented feasibility method for a hybrid photovoltaic (PV)-battery energy storage (BES) system by analyzing a real life house in Istanbul, Turkey, as a case study. The hourly electricity demand of the house was estimated by carrying out a detailed survey of the life style and daily habits of the household. No algorithm of any kind was used for the estimation of the energy demand with the exception of relating the lighting requirement to the daylight hours and the heating and cooling requirements to the seasonal weather changes. The developed method estimates the annual demand with an overall error of 8.68%. The net grid dependency and the feasibility of the PV-BES system was calculated for different combinations of PV and BES system sizes. It was found that when the maximum available roof area is used for PV installation and when the BES system size is increased, it is possible to achieve almost zero net grid dependency, and it is estimated that houses that are in regions with more abundant solar radiation and/or with lower annual electricity consumption, can reach zero net grid dependency. However, the feasibility indicator, which is the payback period, turned out to be no less than 25 years in any of the scenarios. The reasons for the infeasibility are the high prices of PV and BES systems as well as the current restriction in the regulations in Turkey, which prevents BES system owners from participating in unlicensed energy generation schemes and selling excess electricity back to the grid. In order to overcome this situation, regulations should be updated to allow BES system owners to benefit from feed-in-tariff schemes, thereby increasing the popularity of both PV and BES usage in Turkey.

scholarly journals Joint Analysis of Cost and Energy Savings for Preliminary Design Alternative Assessment

2020 ◽  
Vol 12 (18) ◽  
pp. 7507
Author(s):  
Carlo Iapige De Gaetani ◽  
Andrea Macchi ◽  
Pasquale Perri
Keyword(s):  
Energy Demand ◽  
Alternative Assessment ◽  
Energy Savings ◽  
Life Cycles ◽  
Decision Makers ◽  
Joint Analysis ◽  
Energy Demands ◽  
Design Alternatives ◽  
The Impact

The building sector plays a central role in addressing the problem of global energy consumption. Therefore, effective design measures need to be taken to ensure efficient usage and management of new structures. The challenging task for designers is to reduce energy demands while maintaining a high-quality indoor environment and low costs of construction and operations. This study proposes a methodological framework that enables decision-makers to resolve conflicts between energy demand and life cycle costs. A case study is analyzed to validate the proposed method, adopting different solutions for walls, roofs, floors, windows, window-to-wall ratios and geographical locations. Models are created on the basis of all the possible combinations between these elements, enriched by their thermal properties and construction/management costs. After the alternative models are defined, energy analyses are carried out for an estimation of consumption. By calculating the total cost of each model as the sum of construction, energy and maintenance costs, a joint analysis is carried out for variable life cycles. The obtained results from the proposed method confirm the importance of a preliminary assessment from both energy and cost points of view, and demonstrate the impact of considering different building life cycles on the choice of design alternatives.

scholarly journals Towards Green and Smart Seaports: Renewable Energy and Automation Technologies for Bulk Cargo Loading Operations

2021 ◽  
Vol 25 (1) ◽  
pp. 650-665
Author(s):  
Robert Philipp ◽  
Gunnar Prause ◽  
Eunice O. Olaniyi ◽  
Florian Lemke
Keyword(s):  
Energy Demand ◽  
High Energy ◽  
Port Development ◽  
Cargo Handling ◽  
Energy Demands ◽  
Maritime Operations ◽  
Research Gap ◽  
High Share ◽  
Smart Port

Abstract In 2018, 4.1 billion tonnes of freight and 437 million passengers passed through the 1200 European ports. This dimension of geographically concentrated activities is the rationale that ports are characterised by a high-energy demand and a high share of emissions. Driven by a growing awareness for a cleaner environment, a stronger focus on sustainability and intensified environmental regulations, ports are forced to take responsibility when it comes to environmental issues. As a response, in recent studies, the concept of ‘green ports’ emerged. Simultaneously, in the context of digitalisation, the term ‘smart ports’ has received growing attention in the latest scientific discussions, too. Since an important driver towards greener maritime operations is linked to digitalisation, we argue that digital efforts in ports should next to the automation of inherent logistics processes also contribute to reducing the emissions and energy demands. Previous studies have primarily concentrated on the automation of container handling operations. Hence, there exists a research gap concerning the automation of bulk cargo handling operations in ports. Thus, this study addresses the question of how to automate the dry bulk cargo loading operations in the frame of a green and smart port development. The developed case study refers to the seaport of Wismar, whereby the results show that the digitalisation and greener port operations can be successfully aligned. Overall, this study extends the discussion on green and smart port development, while it contributes to the scientific literature by proving that both conceptual ideas can be achieved in the operating business.

scholarly journals Integration of Reversible Heat Pumps in Trigeneration Systems for Low-Temperature Renewable District Heating and Cooling Microgrids

2019 ◽  
Vol 9 (15) ◽  
pp. 3194 ◽  
Author(s):  
Urbanucci ◽  
Testi ◽  
Bruno
Keyword(s):  
Low Temperature ◽  
Carbon Dioxide Emissions ◽  
Energy Demand ◽  
Water Distribution ◽  
District Heating ◽  
Energy System ◽  
Heat Pumps ◽  
Energy Technologies ◽  
Heating And Cooling ◽  
Viable Solution

District heating and cooling networks based on trigeneration systems and renewable energy technologies are widely acknowledged as an energy efficient and environmentally benign solution. These energy systems generally include back-up units, namely fossil-fuel boilers and electric chillers, to enhance system flexibility and cover peak energy demand. On the other hand, 4th generation district heating networks are characterized by low-temperature water distribution to improve energy and exergy efficiencies. Moreover, reversible heat pumps are a versatile technology, capable of providing both heating and cooling, alternately. In this paper, the integration of reversible heat pumps as single back-up units in hybrid renewable trigeneration systems serving low-energy micro-district heating and cooling networks is investigated. A detailed modeling of the system is provided, considering part-load and ambient condition effects on the performance of the units. Size and annual operation of the proposed system are optimized in a case study, namely a large office building located in Pisa (Italy), by means of a genetic algorithm-based procedure. A comparison with the conventional trigeneration system is performed in terms of economic and environmental perspectives. Results show that the integration of reversible heat pumps is an economically viable solution capable of reducing by 7% the equivalent annual cost, increasing the installed power of renewables up to 23%, and lowering by 11% carbon dioxide emissions, compared to the energy system with conventional back-up units.

scholarly journals Impact of Shape Factor on Energy Demand, CO2 Emissions and Energy Cost of Residential Buildings in Cold Oceanic Climates: Case Study of South Chile

2021 ◽  
Vol 13 (17) ◽  
pp. 9491
Author(s):  
Manuel Carpio ◽  
David Carrasco
Keyword(s):  
Co2 Emissions ◽  
Shape Factor ◽  
Energy Demand ◽  
Architectural Design ◽  
Residential Buildings ◽  
Thermal Transmittance ◽  
Energy Demands ◽  
Oceanic Climate ◽  
The Impact

The increase in energy consumption that occurs in the residential sector implies a higher consumption of natural resources and, therefore, an increase in pollution and a degradation of the ecosystem. An optimal use of materials in the thermal envelope, together with efficient measures in the passive architectural design process, translate into lower energy demands in residential buildings. The objective of this study is to analyse and compare, through simulating different models, the impact of the shape factor on energy demand and CO2 emissions depending on the type of construction solution used in the envelope in a cold oceanic climate in South Chile. Five models with different geometries were considered based on their relationship between exposed surface and volume. Additionally, three construction solutions were chosen so that their thermal transmittance gradually complied with the values required by thermal regulations according to the climatic zone considered. Other parameters were equally established for all simulations so that their comparison was objective. Ninety case studies were obtained. Research has shown that an appropriate design, considering a shape factor suitable below 0.767 for the type of cold oceanic climate, implies a decrease in energy demand, which increased when considering architectural designs in the envelope with high values of thermal resistance.

scholarly journals Optimization of Modernization of a Single-Family Building in Poland Including Thermal Comfort

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2925
Author(s):  
Bernard Zawada ◽  
Joanna Rucińska
Keyword(s):  
Thermal Comfort ◽  
Energy Demand ◽  
Primary Energy ◽  
Separate Analysis ◽  
Negative Consequences ◽  
Single Family ◽  
Heating And Cooling ◽  
Energy Demands ◽  
Modernization Process ◽  
The Impact

The impact of thermal comfort demand on the renovation process was carried out on an optimization basis for the thermo-modernization process of an exemplary single-family home located in Warsaw. The verified TRNSYS simulation program was used to generate a set of variants of building modernization solutions. This variants set was used afterwards as a database for optimization. The analysis performed includes the internal air temperature, indicators of thermal comfort (PPD), and annual energy demand for heating and cooling, and investment costs of modernization building. The results indicated the importance of analyzing various variants of building modernization solutions. Performing modernization without analyzing its effects can have positive as well as negative consequences, e.g., achieving a significant reduction in the primary energy demands at the expense of the deteriorated thermal comfort of users. It was shown that separate analysis of indicators leads to completely different solutions and should not be recommended during modernization of single-family buildings.

scholarly journals OPTIMISATION OF BUILDING ENERGY SYSTEM TECHNOLOGY CONFIGURATION USING MULTI-CRITERIA DECISION MAKING METHODS / DAUGIAKRITERIŲ METODŲ TAIKYMAS RACIONALIAM PASTATO ENERGETINĖS SISTEMOS TECHNOLOGIJŲ DERINIUI NUSTATYTI

2013 ◽  
Vol 5 (4) ◽  
pp. 410-422 ◽  
Author(s):  
Rasa Džiugaitė-Tumėnienė ◽  
Milena Medineckienė
Keyword(s):  
Decision Making ◽  
Energy Demand ◽  
Energy System ◽  
Building Energy ◽  
Optimal Decision ◽  
Multi Criteria Decision Making ◽  
System Technology ◽  
Exponential Weighting ◽  
Building Energy System

This article presents the evaluation and optimization algorithm of the building energy system. Two main objectives have been achieved: the optimal configuration of the building energy system has been defined, which minimizes the use of non-renewable sources and reduces the environmental impact of the building. Energy demand for the house has been simulated employing DesignBuilder software. Five configurations of technologies for the building energy system have been chosen and simulated applying Polysun software in order to define the seasonal energy efficiency of the generators of each configuration. Multi-criteria decision making methods SAW (Simple Additive Weight), COPRAS (COmplex PRoportion ASsessment) and MEW (Multiplicative Exponential Weighting) have been used for finding the optimal decision on this case study. Article in Lithuanian. Santrauka Pateikiamas mažai energijos vartojančio gyvenamojo namo energetinės sistemos vertinimo ir optimizavimo algoritmas. Šio tyrimo metu, siekiant nustatyti racionalų realiai pritaikomą pastato energetinės sistemos technologijų derinį, įgyvendinti du pagrindiniai tikslai: parinktas derinys, kurį taikant maksimaliai išnaudojami atsinaujinantieji energijos ištekliai ir sumažinamos sistemos išmetamų CO2 dujų emisijos. DesignBuilder kompiuterine programa atliktas energinis modeliavimas pastato energijos reikmėms nustatyti. Esamam gyvenamajam namui parinkti penki energetinės sistemos technologijų deriniai. Atliktas derinių modeliavimas Polysun programa, nustatytas kiekvieno derinio generatoriaus sezoninis energinis efektyvumas. Įvairiapusiškai racionaliam sprendimui priimti buvo taikyti daugiakriterio vertinimo metodai: SAW (Simple Additive Weight), COPRAS (COmplex PRoportion ASsessment) ir MEW (Multiplicative Exponential Weighting).

Energy Efficient Operation of University Hostel Buildings Under Indoor Environmental Quality Requirements

2012 ◽  
Vol 1 (2) ◽  
pp. 96-109 ◽  
Author(s):  
Ahmed A. Medhat A. Fahim ◽  
Essam E. Khalil
Keyword(s):  
Environmental Quality ◽  
Energy Demand ◽  
Immigrant Students ◽  
Cooling Capacity ◽  
Indoor Environmental Quality ◽  
Efficient Operation ◽  
Energy Demands ◽  
Indoor Conditions ◽  
Occupation Rate

This paper investigates the influence of Indoor Environmental Quality [IEQ] requirements associated with occupation regimes on the criterion of energy demands for Heating, Ventilating and Air-Conditioning (HVAC) central systems installed in Cairo, Egypt. This paper focuses on the effects of occupation rate profiles with IEQ thermal parameters such as air dry-bulb temperatures and local air velocities. It is applied as a case study “10-Stories Hostel of 6000 m2 built-up area” that is utilized by immigrant students that migrate to Cairo for their University studies. They are termed here in this work as Egyptian Citizens [EC]. The occupation rate schedules and operation profiles for each source of heat inside space shall be incorporated to simulate the reality. These profiles and schedules should be added to the local energy code as a guideline for designers. Although in this case study the obtained results from simulation program match the total actual energy bills, sometimes, with multi-use apartments additional factors. The effect of Effective Temperatures [ET*] (temperature for constant thermal sensations) is vital as it can lead to reduce the cooling capacity by increasing the room temperature against indoor relative humidity for the same comfort sensation. These two concepts will save on the project total energy demand, in addition to introducing new design criteria for acceptable indoor conditions.

scholarly journals Acquiring the Foremost Window Allocation Strategy to Achieve the Best Trade-Off Among Energy, Environmental, and Comfort Criteria in a Building

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3962
Author(s):  
Seyedeh Farzaneh Mousavi Motlagh ◽  
Ali Sohani ◽  
Mohammad Djavad Saghafi ◽  
Hoseyn Sayyaadi ◽  
Benedetto Nastasi
Keyword(s):  
Residential Buildings ◽  
Trade Off ◽  
The North ◽  
Heating And Cooling ◽  
Energy Demands ◽  
Building Facades ◽  
Lighting Energy ◽  
Order Preference ◽  
Comfort Criteria

The purpose of this investigation is to propose a way for acquiring the foremost window allocation scheme to have the best trade-off among energy, environmental, and comfort criteria in a building. An advanced decision-making tool, named the technique for order preference by similarity to ideal solution (TOPSIS), is utilized to find the best building amongst different alternatives for having windows on the building façades. Three conditions, namely two parallel, two perpendicular, and three façades, considered as A, B, and C types, respectively, are investigated. For each type, four possible orientations are studied. Heating, cooling, and lighting energy demands in addition to carbon dioxide equivalent emission and thermal and visual comfort are taken into account as the investigated criteria, and they are all evaluated in a simulation environment. The results show that for the modular residential buildings chosen as the case study and located in Tehran, Iran, having windows on the north and east façades is the best scheme. This alternative, which belongs to the B type, has about 40% and 37% lower heating and cooling energy demands than the C type’s foremost alternative. It is also able to provide about 10% better CO2 equivalent emission and 28% higher thermal comfort.

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