- •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
1.6.5.1.4. Flash and ultra-rapid pyrolysis
Flash pyrolysis is the process in which the reaction time is of only several seconds or even less. The heating rate is very high. This requires special reactor configuration in which biomass residence times are only of few seconds. Two of appropriate designs are entrained flow reactor and the fluidized bed reactor. Flash pyrolysis of any kind of biomass requires rapid heating and therefore the particle size should be fairly small, i.e., approximately 105–250 µm [5].
Flash pyrolysis is of the following types:
flash hydro-pyrolysis: Hydro-pyrolysis is flash pyrolysis done in hydrogen atmosphere at a pressure up to 20 MPa;
rapid thermal process: It is a particular heat transfer process with very short heat residence times (between 30 ms and 1.5 s). It is done at temperatures between 400 and 950 oC. Rapid de-polymerization and cracking of feed stocks takes place. Rapid heating eliminates the side reactions whereby giving products with comparable viscosity to diesel oil;
solar flash pyrolysis: Concentrated solar radiation can be used to perform flash pyrolysis. The solar energy can be obtained through devices like solar towers, dish connectors, solar furnaces, etc.;
vacuum flash pyrolysis: In this process, pyrolysis is done under vacuum. It limits the secondary decomposition reactions, which in its turn gives high oil yield and low gas yield.
The vacuum facilitates the removal of the condensable products from the hot reaction
zone. This prevents further cracking and further re-condensation reactions [5].
Table 4. Product yield with temperature from flash pyrolysis of mixed wood waste [11]
Temperature (oC) |
Char (wt%) |
Liquid (wt%) |
Gases (wt%) |
400 |
24.1 |
65.5 |
10.2 |
450 |
21.4 |
65.7 |
11.1 |
500 |
18.9 |
66.0 |
14.6 |
550 |
17.3 |
67.0 |
14.9 |
550 |
16.7 |
67.8 |
15.7 |
550 |
17.1 |
66.2 |
15.2 |
Table 4 reports temperature influence in the range of 400 to 550 oC on products yield from flash pyrolysis of mixed wood waste in a fluidized bed reactor. It is seen that liquid increased marginally where as significant increase in gas yield was observed. Char quantity decreased, as the temperature is increased.
A summary of experimental data presented in [5] evidences that there is a temperature optimum around 500 oC corresponding to maximum liquid yield from flash pyrolysis of all studied biomass.
Ultra-rapid pyrolysis involves extremely fast mixing of biomass with a heat carrier solid, resulting in a very high heat-transfer and hence heating rate. A rapid quenching of the primary product follows the pyrolysis, occurring in its reactor. A gas–solid separator separates the hot heat-carrier solids from the non-condensable gases and primary product vapours, and returns them to the mixer. They are then heated in a separate combustor. Then a non-oxidizing gas transports the hot solids to the mixer (see Figure 13a). A precisely controlled short uniform residence time is an important feature of ultra-rapid pyrolysis. To maximize the product yield of gas, the pyrolysis temperature is around 1000 °C for gas and around 650 °C for liquid [4].