Lecture 8 – Energy Hubs and Aggregation Flashcards
What is an energy hub?
The Energy Hub (EH) concept is a promising option for optimal management of MES and achieving a comprehensive model for sustainable energy systems. It is the place where the production, conversion, storage and consumption of different energy carriers takes place.
What is a Smart energy hub (SEH)?
EH located in a smart grid that is equipped with smart meters for both electricity and natural gas networks using appropriate communication infrastructures.
Why is the optimal performance of multi-energy systems (MES) good?
• Optimal performance of multi-energy systems (MES) can lead to technical, economic, and environmental advantages
− Higher system reliability
− Lower operating costs, fuel consumption, and emissions of the system
• Successful performance requires an integrated management framework that can manage the various components of the system optimally
In what ways can energy hubs be a main part of future energy networks?
− Can provides a great opportunity for energy production, conversion and storage in such coupled infrastructures for system planners, operators and prosumers to move towards more energy-efficient and flexible systems
− Can be seen as local concentrated set of energy infrastructure
− Can be implemented in different dimensional range from a single household up to an entire city model
− Integrating different energy carriers in an energy hub helps system operator to maximize social welfare in a greater optimization space
− Can enable energy users to flexibly switch the energy sources with accordance to different energy prices
− Converting different energy carriers to other forms provide accumulation of larger amount of renewable energy and reuse of them in the future
− Total operational costs can be substantially reduced and a large amount of investments costs could be saved
What are the main functions of energy hubs?
• Integration of various energy sources: by combining different energy inputs like solar, wind, biomass, natural gas, and electricity
• Energy conversion: means converting one form of energy to another, for instance, using natural gas to generate electricity or heat
• Energy storage: energy can be store in different forms (e.g., batteries for electricity, thermal storage for heat) at input and output to ensure a reliable supply
• Energy management: the hub should optimize the use of available energy resources to meet demand efficiently and sustainably, often through advanced control and monitoring systems
• Distribution and supply: the effective and efficient distribution of energy to various end-users, which could include residential, commercial, and industrial sectors should be ensure
What is the problem related to resources in conventional energy systems?
Significant loss of primary energy in conventional energy systems, due to:
− The low efficiency of energy production from thermal power plants
− Losses related to transmission and distribution of energy in the hierarchical structures
How can EH help sole the problem related to resources?
EH models requiring moving towards the increased use of sustainable and clean energy sources, such as renewables, especially in the form of distributed energy resources (DER)
Why are DERs important in EH to solve issues regarding resources?
• DERs as power generation systems near the consumption site, result in lower energy costs, reduced transmission and distribution losses and higher energy efficiency.
• DERs with the ability of using different technologies such as micro gas turbines, and renewable technologies
How are DERs used in relation to conversion and transmission?
DER (e.g., electric machines, gas turbines, internal combustion engines, fuel cells, thermo-electric converters, pumps, transformers, inverters, and heat exchangers) are used to modify the input carriers and getting them to a quality and quantity level and mode that is usable in the output.
What are the possible types of input to output connections in EH models?
− Direct connections: typically used to convey an energy carrier to the output without conversion or change in its quality.
− Conversions: converters are used to convert energy carriers to other types for use in the output.
In what sectors are energy hubs applied?
- residential
- commercial
- industrial
Why are energy hubs needed in the residential sector?
• Consumption of a significant part of the produced energy in each country
• Considerable energy losses due to:
≡ Extensive distribution and long transmission networks
≡ Poor management of consumption by consumers
≡ The lack of controllable residential loads and low efficiency of the equipment
What are the solutions to the problems with the residential sector?
• Raising energy prices due to the resource constraints, increasing energy demand, and markets deregulation – need for increasing energy efficiency
• Possible increase of energy efficiency – Home energy management system (HEMS) as solution
Why are energy hubs used in the commercial sector?
• Operational optimization of CHP units in the commercial buildings
• Efficiency improvements such as successful participation in the DSM programs critical for efficient energy consumption and environmental impact reduction:
≡ Technological efforts such as energy audits
≡ The culture and behavioral training of the occupier
≡ Building energy management system (BEMS)
• Modeling and realizing BEMS in the commercial sector
Why are energy hubs used in the industrial sector?
• Largest primary energy consumer
• Possible efficiency improvements:
≡ Technical and technological improvements
≡ Policy making and behavioral training: government policies to encouraging industry
owners to improve their efficiency
≡ Industry Energy Management System (IEMS): integrating management to determine the energy consumption when and where needed
≡ Benefiting from energy-saving methods such as CHP, waste heat recovery, DSM participation, and integration of RES
