- •Energy Saving Technologies Riga Technical University
- •Content
- •Introduction 10
- •1. Energy Saving Technologies in generation, conversion of electrical energy 11
- •Executive summary
- •Introduction
- •1.Energy Saving Technologies in generation, conversion of electrical energy
- •1.1.Cogeneration
- •1.1.1.Introduction
- •1.1.2.Performance indices of cogeneration systems
- •1.1.3.Types of cogeneration systems
- •Comparison of Fuel Cell Systems [12].
- •1.1.4.Distributed energy resources
- •Characteristics of cchp Systems [15].
- •References
- •1.2.Smart metering concept
- •1.2.1.Introduction
- •1.2.2.Communication concept of smart metering
- •1.2.2.1.Customer domain
- •1.2.2.2.Critical infrastructure energy domain
- •1.2.2.3.The utility business market communication domain
- •1.2.2.4.Third parties services - data analysis
- •Ip service provider’s domain
- •1.2.3.Wireless sensor networks in smart metering
- •1.2.3.1.Main characteristics of wireless sensor networks
- •1.2.3.2.Examples of application of wireless sensor networks
- •1.2.4.Security issues
- •1.2.5.The future of smart metering
- •1.3. Energy from biomass
- •1.3.1. Biomass resources
- •Yeld of Som Biomass Types [2].
- •Yield of Agricultural Residues [2].
- •1.3.1.Biomass conversion technologies
- •Characteristics of Solid Biofuels and their Effects.
- •Ultimate Analysis of Different Solid Biofuels (Dry Basis) [5, 6, 7].
- •Proximate Analysis of Solid Biofuels (Dry Basis) [5, 6, 7].
- •Characteristics of Compacted Biomass [2].
- •Higher Heating Value of Solid Biofuels [8, 9, 10].
- •Composition of Biomass Ash [5, 13].
- •Types of Biomass Furnaces [14].
- •Heat Capacity of Combustible Gas [17].
- •Contaminants in Combustible Gas: Problems and Cleanup Methods [17].
- •Syngas Quality Parameters.
- •Operating Parameters of Pyrolysis Processes.
- •1.4.Energy Storage
- •1.4.1.Introduction
- •1.4.2.Classification of energy storage technologies
- •Types of Energy Storage Technologies and Their Applications [2].
- •1.4.3.Characteristics of energy storage techniques
- •1.4.4.Direct electric storage
- •1.4.5.Electrochemical energy storage
- •1.4.6.Mechanical energy storage
- •The response time of sudden changes in electrical demand for power plants [5].
- •1.4.7.Thermal energy storage
- •Physical Properties of Sensible Energy Storage Media [7, 8]
- •Commercial Phase Change Materials which can be Used for Heat Storage in the Buildings [10].
- •Properties of Some Phase Change Materials Produced by eps Ltd, uk [11].
- •Properties of Some Phase Change Materials Produced by teap Energy, Australia [11].
- •Properties of some phase change materials (paraffins) produced by the Rubitherm GmbH Germany [11].
- •Chemical Storage Materials and Reactions [8].
- •Main Characteristics of Energy Storage Materials [8].
- •References
- •1.5.Waste heat recovery
- •1.5.1.Characteristics of waste heat
- •Sources of waste heat at high-temperature range [2].
- •Sources of Waste Heat at Medium-Temperature Range [2].
- •Sources of Waste Heat at Low-Temperature Range [2].
- •1.5.2.Waste heat recovery systems
- •Waste Heat Recovery Systems [3].
- •Heat Exchangers Characteristics.
- •References
- •1.6.Energy Saving Technologies of the Thermochemical Conversion of Biomass and lignocarbonaceous Waste
- •1.6.1.Introduction
- •1.6.2.Pyrolysis
- •1.6.3.1.2 Torrefaction
- •1.6.4.1.3 Fast pyrolysis
- •1.6.5.1.4. Flash and ultra-rapid pyrolysis
- •1.6.6.1.5. Solar driven pyrolysis
- •1.6 Pyrolizer types
- •1.7.Gasification
- •1.8. Poly-generation of heat, power and biofuel
- •1.9.Design of renewable energy systems for small (local) consumers - description of a software for design and examples of design exercises.
- •1.9.1.Introduction.
- •1.9.2.A software for design renewable energy systems.
- •1.9.3.Description of the polysun platform
- •1.9.3.1.Polysun modules
- •1.9.3.2.User Interface
- •1.9.3.2.1.Menu bar
- •1.9.3.2.2.Icon bar
- •1.9.3.2.3.Managing the project.
- •1.9.3.2.4.Project tools
- •1.9.4.Creating a project
- •1.9.4.1.Design steps of the simple solar system.
- •1.9.4.2.Design steps of the pv system.
- •1.9.5.Result analysis and reports
- •1.9.5.1.The results of simulation
- •1.9.5.2.Reports
- •1.9.6.Literature
- •Conclusion
- •2.Energy Saving Technologies in transmission, distribution of electrical energy Energy Cost and Power Loss Minimization in Distribution Networks with Distributed Generation
- •Introduction
- •2.1.Opf problem formulation for distribution networks
- •2.1.1.Objective function
- •2.1.2.Constraints
- •Dg units modeling for optimal power flow
- •Opf Solution Using Multi-objective Genetic Algorithm
- •Opf Solution Using Gravitational Search Algorithm
- •2.2.Dc transmission systems
- •3. Energy Saving Technologies: in industry
- •3.1. Electric Motors
- •3.2. Electrical Drives
- •3.1.Waste heat utilization technologies
- •Introduction
- •1 Sources of waste heat
- •2 Main definitions used for heat waste assessment
- •3 Using of waste heat for heating and hot water supply. Equipment for using of industrial waste heat
- •3.1 Closed-circuit schemes of waste heat utilization
- •3.2 Opened-circuit schemes of waste heat utilization
- •Indirect Contact Condensation Recover
- •4. Utilization of low-temperature heat waste
- •4.1 Heat pumps
- •Common types of industrial heat pumps
- •4.2 Applications of heat pumps in drying process
- •4.2.1 Closed-cycle mechanical heat pumps for lumber drying
- •4.2.2 Evaporation - open-cycle mechanical vapour compression (mvc) for sugar solution concentration
- •4.2.3 Thermo-compression for paper-dryer flash steam recovery
- •4.3 Heat pumps working fluids
- •5 Using of waste heat for power generation
- •5.1 The opportunity for waste heat to power generation
- •5.2 Applicable Technologies
- •5.3 Applications
- •Using of combustible waste
- •7 Economic efficiency analysis of heat waste utilization
- •4.Energy Saving Technologies: in public and private sector
- •4.1.Building: fundamental physical processes in buildings and building envelopes. Reduction of heat losses. Heating and conditioning. Heat pumps.
- •5.Supercapacitors
- •Viesturs Brazis
- •5.1.Supercapacitor energy storage
- •5.1.1.Introduction
- •5.1.2.Supercapacitor design
- •5.1.3.Supercapacitor energy storage systems
- •5.1.4.Simulation of supercapacitor energy storage system
- •5.1.5.Ess scaling
- •5.1.6.Conclusions
- •5.1.7.Tasks
- •References
- •5. Standartisation and legal bases on existing Energy Saving Technologies
- •5.2.Introduction
- •5.3.Legistlative base mandatory for eu Member states
- •5.4.Legistlative base non - mandatory for eu Member states
- •5.5.Eu supported actions for development of Energy Saving Technologies
- •5.6.Iso 50001 - Energy management
- •5.7.Conclusions
- •References
3.2 Opened-circuit schemes of waste heat utilization
These systems are usually used for low-temperature heat waste utilization. Much industrial waste heat is in the lowtemperature range. For example, combustion systems such as boilers frequently use recovery technologies that exhaust gases at around 150°180°C. Meanwhile, large quantities of waste heat can be found in industrial cooling water and cooling air.
In the case of combustion exhaust gases, substantial heat can be recovered if water vapor contained in the gases is cooled to lower temperatures. Minimum temperature limits around 120150°C are frequently employed in order to prevent water in the exhaust gases from condensing and depositing corrosive substances on the heat exchanger surface. However, cooling the flue gas further could significantly increase heat recovery by allowing the latent heat of vaporization to be recovered. This latent heat comprises a significant portion of the energy contained in exhaust gases. Technologies that can minimize chemical attack while cooling exhaust gases below the condensation point can achieve significant increases in energy efficiency via recovering the latent heat of evaporation. If gases are cooled from 150°C to 60°C, then the facility can obtain a 3% efficiency increase. Cooling gases further 38°C captures a portion of the latent heat and can provide an 11% efficiency increase.
Lowtemperature heat recovery faces at least three challenges:
corrosion of the heat exchanger surface: As water vapor contained in the exhaust gas cools, some of it will condense and deposit corrosive solids and liquids on the heat exchange surface. The heat exchanger must be designed to withstand exposure to these corrosive deposits. This generally requires using advanced materials, or frequently replacing components of the heat exchanger, which is often uneconomical;
large heat exchange surfaces required for heat transfer: Heat transfer rates are a function of the thermal conductivity of the heat exchange material, the temperature difference between the two fluid streams, and the surface area of the heat exchanger. Since lowtemperature waste heat will involve a smaller temperature gradient between two fluid streams, larger surface areas are required for heat transfer. This limits the economics of heat exchangers;
Finding a use for lowtemperature heat. Recovering heat in the lowtemperature range will only make sense if the plant has a use for lowtemperature heat. Potential enduses include domestic hot water, space heating, and lowtemperature process heating. Other options include using a heat pump to “upgrade” heat to a higher temperature to serve a load requiring higher temperatures.
Technologies are available that can cool gases below dew point temperatures to recover lowtemperature waste heat. Options include deep economizers, indirect contact condensation recovery, direct contact condensation recovery, and recently developed transport membrane condensers. Commercialization has been limited due to high costs and because facilities lack an enduse for the recovered heat. When facilities lack an enduse for waste heat, some have found other means for recovery, including heat pumps and lowtemperature power generation. These technologies are also frequently limited by economic constraints.
Deep Economizers
Deep economizers are designed to cool exhaust gas to 65°C71°C and to withstand the acidic condensate depositing on its surface. Designs include the following options:
installing a “throwaway” section on the cold end of the economizer. The tubing in the cold end will degrade over time and will need to be repeatedly replaced. The frequency of replacements will depend on the flue gas composition and the material of construction;
designing the economizer with stainless steel tubes. Stainless steel can withstand acidic gases better than the mild steel typically used in construction;
using carbon steel for the majority of the heat exchanger, but using stainless steel tubes in the cold end where acidic deposits will occur;
using glasstubed heat exchangers (mainly for gasgas applications such as air preheaters);
using advanced materials such as Teflon.