The Pressure is on
in Heat Storage
We have our sights firmly set on making carbon capture a viable option and increasing the efficiency of compressed air energy storage. We are also promoting improved and more flexible heat storage management in point-of-use cogeneration systems.
Compressed air energy storage system - Collecting and storing offshore energy in the form of compressed air
University of Nottingham, School of Mechanical, Materials and Manufacturing Engineering
Central to this concept is the view that storing energy in the form of compressed air in large flexible containers (‘energy bags’) at considerable depths on the sea bed is technically feasible, economically attractive and environmentally friendly.
This project makes the first step towards an integrated offshore system con-sisting of compressed air storage devices and renewable energy production. As a result it has been possible to considerably reduce the negative effects on the power system on land, which are due to unforeseen fluctuations. The re-search activity includes the following work packages: Designing and develop-ing the flexible underwater container, developing heat exchangers for the best possible utilisation of the heat generated during compression and the use of floating heat storage devices and additional equipment (‘thermal top-up’). This is followed by the expander configuration and system simulations as well as an evaluation of cost-effectiveness.
Central to this concept is the view that storing energy in the form of compressed air in large flexible containers (‘energy bags’) at considerable depths on the sea bed is technically feasible, economically attractive and environmentally friendly.
This project makes the first step towards an integrated offshore system con-sisting of compressed air storage devices and renewable energy production. As a result it has been possible to considerably reduce the negative effects on the power system on land, which are due to unforeseen fluctuations. The re-search activity includes the following work packages: Designing and develop-ing the flexible underwater container, developing heat exchangers for the best possible utilisation of the heat generated during compression and the use of floating heat storage devices and additional equipment (‘thermal top-up’). This is followed by the expander configuration and system simulations as well as an evaluation of cost-effectiveness.
New compressed air storage plant - Isobaric adiabatic gas and steam compressed air storage plant
Institute for Heat and Fuel Technology, Technische Universität Braunschweig (Brunswick Technical University)
Energy storage systems are essential for the operation of supply networks. Their importance is increasing due to the use of renewable forms of energy.
This project studies new ways of improving compressed air storage systems, which are supplied with wind energy at times of oversupply and supply elec-tricity to the system during times of demand. The planned compressed air storage power station is operated on an isobaric or almost isobaric basis. To further increase the level of efficiency, researchers use a heat storage system and a combined cycle gas and steam turbine unit.
The compressed air storage power station studied here has the option of be-ing operated conventionally and also works when there is a lack of wind power and the storage systems are empty. This reduces downtime and the investment portion of costs in the energy prices. Fundamental thermodynamic questions about the best design of the plant and the heat storage system are studied in the project just as much as how to best integrate the storage power station in a network made up of existing storage systems.
Energy storage systems are essential for the operation of supply networks. Their importance is increasing due to the use of renewable forms of energy.
This project studies new ways of improving compressed air storage systems, which are supplied with wind energy at times of oversupply and supply elec-tricity to the system during times of demand. The planned compressed air storage power station is operated on an isobaric or almost isobaric basis. To further increase the level of efficiency, researchers use a heat storage system and a combined cycle gas and steam turbine unit.
The compressed air storage power station studied here has the option of be-ing operated conventionally and also works when there is a lack of wind power and the storage systems are empty. This reduces downtime and the investment portion of costs in the energy prices. Fundamental thermodynamic questions about the best design of the plant and the heat storage system are studied in the project just as much as how to best integrate the storage power station in a network made up of existing storage systems.
Control system for CHP plants - Innovative heat storage management for micro CHP plants
Institute for Energy Economy and Application Technology, Technical University Munich
In the case of combined heat and power (CHP) systems, the processes of taking energy from and feeding energy into the grid can only be controlled to a limited extent. Innovative heat storage management can break the link between heat production and demand at CHP plants.
The controlled operation of CHP modules enables a steady gas demand and power generation adapted to the network load, which is not possible with the previous systems and impairs their cost-effectiveness. Multifunctional heating systems consist of a CHP module, heat storage system and a peak load boiler. Theoretical load profiles are first designed for the plants based on typical days and tested in practice using non-linear influencing factors. The control system can impress feedback controls on the CHP module, thus safeguarding the developed storage management system. The results represent future load profiles of electricity and natural gas. Finally the profiles developed are evaluated. A defined supply area is used to show up feedback effects from multifunctional heating systems on the supply network.
In the case of combined heat and power (CHP) systems, the processes of taking energy from and feeding energy into the grid can only be controlled to a limited extent. Innovative heat storage management can break the link between heat production and demand at CHP plants.
The controlled operation of CHP modules enables a steady gas demand and power generation adapted to the network load, which is not possible with the previous systems and impairs their cost-effectiveness. Multifunctional heating systems consist of a CHP module, heat storage system and a peak load boiler. Theoretical load profiles are first designed for the plants based on typical days and tested in practice using non-linear influencing factors. The control system can impress feedback controls on the CHP module, thus safeguarding the developed storage management system. The results represent future load profiles of electricity and natural gas. Finally the profiles developed are evaluated. A defined supply area is used to show up feedback effects from multifunctional heating systems on the supply network.
Gas mixtures as basis - Equation of state for combustion gases (EOS-CG) and combustion gas-like mixtures
Chair of Thermodynamics, Ruhr University Bochum (Ruhr-Universität Bochum)
Like electricity storage, carbon capture and storage (CCS) is seen as a key technology for reducing greenhouse gases. Both technologies require exact fluid property models.
At high pressure, state variables of gas mixtures and complicated phase equi-libriums have to be accurately calculated. Researchers focus on developing a data model for chemical media, which is sufficiently accurate for all relevant mixtures, temperatures and pressure ratios. As a starting point, the GERG 2004 equation of state is used as an internationally agreed standard for the chemical substance properties of natural gases. The applicability is analysed for mixtures and states that are typical for compressed air storage power sta-tions and CCS processes. The application of the fluid property model is tested in typical simulation programs and the influence on process calculations studied.
Like electricity storage, carbon capture and storage (CCS) is seen as a key technology for reducing greenhouse gases. Both technologies require exact fluid property models.
At high pressure, state variables of gas mixtures and complicated phase equi-libriums have to be accurately calculated. Researchers focus on developing a data model for chemical media, which is sufficiently accurate for all relevant mixtures, temperatures and pressure ratios. As a starting point, the GERG 2004 equation of state is used as an internationally agreed standard for the chemical substance properties of natural gases. The applicability is analysed for mixtures and states that are typical for compressed air storage power sta-tions and CCS processes. The application of the fluid property model is tested in typical simulation programs and the influence on process calculations studied.