scholarly journals Mathematical modeling and optimization of tri-generation systems with reciprocating engines

2010 ◽  
Vol 14 (2) ◽  
pp. 541-553 ◽  
Author(s):  
Mirko Stojiljkovic ◽  
Mladen Stojiljkovic ◽  
Bratislav Blagojevic
Keyword(s):  
Mathematical Model ◽  
Energy Savings ◽  
Optimization Procedure ◽  
Electrical Energy ◽  
Primary Energy ◽  
Optimal Operation ◽  
Electrical Heating ◽  
Heating And Cooling ◽  
Operational Optimization ◽  
Reciprocating Engines

Tri-generation systems are used to simultaneously produce electrical, heating, and cooling energy. These systems are usually more efficient than conventional systems for separate production and have smaller distribution losses since they are often located closer to the consumer. For achievement of the best technical and/or financial results, tri-generation plants have to be properly, i. e. optimally designed and operated. Operational optimization is used for short term production planning, control of tri-generation systems operation and as a part of design level optimization. In this paper an approach to operational optimization of tri-generation plants with reciprocating engines is presented with the following mathematical model. It is also explained how this algorithm might be embedded in some larger optimization procedure. In this approach, the importance of the part load performance of different units of the tri-generation systems is emphasized, especially of co-generation unit, i. e. engine generator set and thus it relies on manufacturers' data and is characterized with relatively high level of details examined. Mathematical model is based on the equipment performance based constraints and demand satisfaction based constraints with the possibility to add more equations if appropriate. Objective function for optimization is benefit-cost function. Optimal operation regimes for typical days for each month are obtained and analyzed. Impact of electrical energy price on pay-back period and primary energy saving is analyzed. Primary energy savings are determined and compared to maximal value that could be obtained.

Technical and Tariff Scenarios Effect on Microturbine Trigenerative Applications

2004 ◽  
Vol 126 (3) ◽  
pp. 581-589 ◽  
Author(s):  
Stefano Campanari ◽  
Ennio Macchi
Keyword(s):  
Energy Savings ◽  
Optimization Procedure ◽  
Operating Mode ◽  
Primary Energy ◽  
Environmental Benefits ◽  
Time Step ◽  
Simulation Code ◽  
Heating And Cooling ◽  
Target Energy ◽  
Micro Turbine

The paper considers the use of gas fired micro turbine generators (MTG) for trigeneration (combined production of electricity, heating, and cooling) applications in tertiary buildings. The importance of the adopted MTG technology is investigated, showing that the high electrical efficiency levels achievable by future advanced ceramic MTGs would improve dramatically the economic competitiveness of the application, as well as the primary energy savings and environmental benefits. Calculations are performed by the simulation code TRIGEN, capable of optimizing the plant operating mode in each time step and integrating the results over the entire year. The requirement of a “target” energy saving index on the optimization procedure is also addressed.

Energy Consumption and Technical Potential of Energy Saving in a Hospital

2008 ◽  
Author(s):  
S. Okamoto
Keyword(s):  
Energy Saving ◽  
Energy Demand ◽  
High Efficiency ◽  
Hospital Setting ◽  
Electrical Energy ◽  
Primary Energy ◽  
Electrical Heating ◽  
Public Network ◽  
Heating And Cooling ◽  
Cogeneration System

This paper describes a study starting from an analysis of typical energy demand profiles in a hospital setting followed by the feasibility study of a cogeneration system (CGS). The concept is a future autonomous system for the combined generation of electrical, heating and cooling energy in the hospital. The driving cogeneration units are two high-efficiency gas engines; this is used to produce the electrical and heat energy. Gas engine is used as a driving unit because of high needs for electrical and heating energy. The natural gas-fuelled reciprocating engine is used to generate 735kW of power. In our case electrical energy will be used only in the Hospital. A deficit in electricity can be also purchased from the public network. The generated steam will be used to drive three steam-fired absorption chillers and delivered to individual consumers of heat. This system is capable of doing simultaneous heating and cooling. No obstacles were recognized for the technical feasibility of CGS. The average ratio between electric and thermal load in the Hospital is suitable to make CGS system operate. A feasibility analysis performed for a non-optimized CGS system predicted a large potential for primary energy saving.

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.

A Case Study of Energy Saving by Cogeneration System in 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 ◽  
Cogeneration System

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 cogeneration system (CGS) under an energy service company (ESCO) project. The CGS 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 will be 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 CGS. The average ratio between electric and thermal loads in the hospital is suitable for CGS system operation. An analysis performed for a non-optimized CGS system predicted a large potential for energy savings.

Technical and Tariff Scenarios Effect on Microturbine Trigenerative Applications

2003 ◽  
Author(s):  
Stefano Campanari ◽  
Ennio Macchi
Keyword(s):  
Energy Savings ◽  
Optimization Procedure ◽  
Operating Mode ◽  
Primary Energy ◽  
Environmental Benefits ◽  
Time Step ◽  
Simulation Code ◽  
Heating And Cooling ◽  
Target Energy ◽  
Micro Turbine

The paper considers the use of gas fired Micro Turbine Generators (MTG) for tri-generation (combined production of electricity, heating and cooling) applications in tertiary buildings. The importance of the adopted MTG technology is investigated, showing that the high electrical efficiency levels achievable by future advanced ceramic MTGs would improve dramatically the economic competitiveness of the application, as well as the primary energy savings and environmental benefits. Calculations are performed by the simulation code TRIGEN, capable of optimizing the plant operating mode in each time step and integrating the results over the entire year. The requirement of a “target” energy saving index on the optimization procedure is also addressed.

scholarly journals KAJIAN SUMBER ENERGI PADA PENGOLAHAN KELAPA SAWIT MENJADI CRUDE PALM OIL (CPO) DI PT. ALNO AGRO UTAMA SUMINDO OIL MILL, BENGKULU UTARA

AGROINTEK ◽  
2017 ◽  
Vol 11 (2) ◽  
pp. 75
Author(s):  
Lukman Hidayat ◽  
Fitri Electrika Dewi Surawan ◽  
Arga Harianda Lumban Raja
Keyword(s):  
Technical Efficiency ◽  
Palm Oil ◽  
Energy Savings ◽  
Energy Analysis ◽  
Electrical Energy ◽  
Primary Energy ◽  
Initial Energy ◽  
Total Efficiency ◽  
Crude Palm Oil ◽  
Energy Needs

Increasing demand for Crude Palm Oil (CPO) as the vegetable oil was causing the industry to cultivate palm oil increased, so that the energy required to produce CPO also increased. The purpose of this study is to identify the type, source and calculate the amount of energy needs, calculate the level of efficiency and energy savings opportunities. Stages of the research are  initial energy analysis, a detailed energy, and energy analysis in processing systems. Based on the research results, to produce each kg of CPO processing capacity of 60 ton TBS / hour with a recovery rate of 20.59% of primary energy needs of 16.200679 MJ / kg. Real boiler efficiency of 45.69%, the real efficiency of the turbine was 94, 86%. Turbine efficiency  to generate electrical energy by 1.09%, the technical efficiency of 66.80% turbines, diesel generators technical efficiency of 47.25%, the technical efficiency of electric motors by 59.37%.  The total efficiency  of  electricity  use by 4,75%, the efficiency of diesel estate of 1.379% and the efficiency of the use of steam at 93.77%. Energy can be saved by 0.0442 MJ / kg with a description of human powered energy of 0.0004316 MJ / kg, energy electrical energy by .04372 MJ / kg. While energy can be stored on the excess energy to fuel biomass boiler was 1.45 MJ / kg

scholarly journals Heat pump systems: A mini review

2021 ◽  
Vol 4 (2) ◽  
pp. 73-81
Author(s):  
Mohammad Omar Temori ◽  
František Vranay
Keyword(s):  
Heat Pump ◽  
Electricity Consumption ◽  
Cost Savings ◽  
Electrical Energy ◽  
Primary Energy ◽  
Heat Pumps ◽  
Coefficient Of Performance ◽  
Heating And Cooling ◽  
Ground Source ◽  
Reduce Electricity Consumption

In this work, a mini review of heat pumps is presented. The work is intended to introduce a technology that can be used to income energy from the natural environment and thus reduce electricity consumption for heating and cooling. A heat pump is a mechanical device that transfers heat from one environmental compartment to another, typically against a temperature gradient (i.e. from cool to hot). In order to do this, an energy input is required: this may be mechanical, electrical or thermal energy. In most modern heat pumps, electrical energy powers a compressor, which drives a compression - expansion cycle of refrigerant fluid between two heat exchanges: a cold evaporator and a warm condenser. The efficiency or coefficient of performance (COP), of a heat pump is defined as the thermal output divided by the primary energy (electricity) input. The COP decreases as the temperature difference between the cool heat source and the warm heat sink increases. An efficient ground source heat pump (GSHP) may achieve a COP of around 4. Heat pumps are ideal for exploiting low-temperature environmental heat sources: the air, surface waters or the ground. They can deliver significant environmental (CO2) and cost savings.

Energy Saving by ESCO (Energy Service Company) Project in Japanese Hospital

2009 ◽  
Author(s):  
S. Okamoto
Keyword(s):  
Energy Demand ◽  
Energy Savings ◽  
High Efficiency ◽  
Hospital Setting ◽  
Electrical Heating ◽  
Public Network ◽  
Service Company ◽  
Heating And Cooling ◽  
Energy Service ◽  
Energy Service Company

This paper describes a study starting from an analysis of typical energy demand profiles in a hospital setting followed by the case study of a cogeneration system (CGS) by an ESCO (Energy Service Company) project. The concept is a future autonomous system for the combined generation of electrical, heating and cooling energy in the hospital. The driving cogeneration units are two high-efficiency gas engines; this is used to produce the electrical and heat energy. Gas engine is used as a driving unit because of high needs for electrical and heating energy. The natural gas-fuelled reciprocating engine is used to generate 735kW of power. In our case electrical energy will be used only in the Hospital. A deficit in electricity can be also purchased from the public network. The generated steam will be used to drive three steam-fired absorption chillers and delivered to individual consumers of heat. This system is capable of doing simultaneous heating and cooling. No obstacles were recognized for the technical feasibility of CGS. The average ratio between electric and thermal load in the Hospital is suitable to make CGS system operate. An analysis performed for a non-optimized CGS system predicted a large potential for energy savings.

scholarly journals Effects of implementation of co-generation in the district heating system of the Faculty of Mechanical Engineering in Nis

2010 ◽  
Vol 14 (suppl.) ◽  
pp. 41-51 ◽  
Author(s):  
Mladen Stojiljkovic ◽  
Mirko Stojiljkovic ◽  
Bratislav Blagojevic ◽  
Goran Vuckovic ◽  
Marko Ignjatovic
Keyword(s):  
Natural Gas ◽  
Energy Savings ◽  
Boiler House ◽  
District Heating ◽  
Electrical Energy ◽  
Heating System ◽  
Primary Energy ◽  
District Heating System ◽  
Heating Systems ◽  
District Heating Systems

Implementation of co-generation of thermal and electrical energy in district heating systems often results with higher overall energy efficiency of the systems, primary energy savings and environmental benefits. Financial results depend on number of parameters, some of which are very difficult to predict. After introduction of feed-in tariffs for generation of electrical energy in Serbia, better conditions for implementation of co-generation are created, although in district heating systems barriers are still present. In this paper, possibilities and effects of implementation of natural gas fired cogeneration engines are examined and presented for the boiler house that is a part of the district heating system owned and operated by the Faculty of Mechanical Engineering in Nis. At the moment, in this boiler house only thermal energy is produced. The boilers are natural gas fired and often operate in low part load regimes. The plant is working only during the heating season. For estimation of effects of implementation of co-generation, referent values are taken from literature or are based on the results of measurements performed on site. Results are presented in the form of primary energy savings and greenhouse gasses emission reduction potentials. Financial aspects are also considered and triangle of costs is shown.

Sign in / Sign up

Export Citation Format

Share Document