Transportation of Thermal Energy Utilizing Thermal Energy Storage Technology (Annex 18)

A key component in a sustainable energy system is to be able to use thermal energy from various sources at a consumer located at a distance from theses sources. For this purpose, the thermal energy has to be transported from one place to another. This could be achieved by using thermal energy storage technology. Depending on the distance, the storage medium could either be pumped through pipelines or for longer distances the TES itself could be transported on a truck or a train. The crucial properties of the TES for the technical and economical feasibility are the storage capacity per volume and weight and the possible charging and discharging power, which affects the possible number of storage cycles per time.

If you want to read the complete proposal click - here - 130 kB .

If you are interested to participate in such an Annex, or if you have related topics, applications or projects which should be included in the formulation of this new Annex, please contact the Operating Agent Victoria Martin at the Royal Institute of Technology, Stockholm, Sweden.

A kick-off workshop has taken place in November 14. – 15. in Bad Tölz, Germany, the first workshop and experts meeting was held in in Tokyo/Japan on November 14th to 15th 2006. Information about these meeting can be found here . The next experts meeting and workshop will be held in Bordeaux on March 28 – 30 2007. For more information and registration please contact Victoria Martin .

The Annex 18 homepage can be found here .


Optimised Industrial Process Heat and Power Generation with Thermal Energy Storage (Annex 19)

Previous activities in the IEA Implementing Agreement “Energy Conservation through Energy Storage” has achieved significant progress in thermal energy storage technologies for energy savings and for reduction of peak demand of energy in buildings and in advancing the prospects of cooling with TES technologies.
The potential for thermal energy storage and regenerative heat transfer for the industrial process heat sector for efficient energy utilisation, heat recovery and storage of high temperature waste heat as well as the need for energy storage for power generation based on new conversion techniques and renewable energy resources (RES) is a concern of several national and international research strategies. Both areas are directed to applications and processes at high temperature. In this context “High Temperature” is defined to be higher than 120 °C as required for comfort heating and where water cannot be applied as heat transfer fluid.

If you are interested to participate in such an Annex, or if you have related topics, applications, materials or techniques which should be included in the work program of this new Annex, please contact rainer.tamme@dlr.de . For general information regarding the procedure to join the IEA ECES implementing contact hauer@muc.zae-bayern.de .

First workshop was organized in Stuttgart on April 4th 2007. For further information please contact Rainer Tamme , the Operating Agent of Annex 19.

If you want to read the complete proposal click - here - 115 kB .

Sustainable Cooling with Thermal Energy Storage (Annex 20)

Renewable and natural energy sources, main components of sustainable energy systems, can only be made continuously available to users through thermal energy storage (TES). In addition to heating TES provides several flexible alternatives for cooling systems. Recent discussions on topics like global warming and heat waves have brought attention once again to energy efficient cooling systems utilizing renewable energy sources. Cooling demand has already been increasing due to the evolving comfort expectations and technological development around the world. Climate change has brought additional challenges for cooling systems designers. New cooling systems must use less and less electricity generated by fossil fuel based systems and still be able to meet the ever increasing and varying demand.

If you want to read the complete Annex text click - here - 118 kB .
A kick-off workshop was organized in Nice, France on June 23, 2004 following the "Cooling Buildings in a Warming Climate" Forum. The minutes of this Annex 20 workshop can be downloaded - here - 88 kB .

The Appendices of the pro memoria can be on the Annex 14 homepage . The concept of the Annex 20 is given in Appendix 2. The first experts meeting and workshop will be in Nagoya, Japan on the 14. – 16. of September. The next experts meeting and workshop will be held in Ankara, Turkey, on November 27 – 28.

The Annex 20 homepage can be found here .


Thermal Response Test for Underground Thermal Energy Storages (Annex 21)

Thermal Response Test (TRT) is a measurement method to determine the heat transfer properties of a borehole heat exchanger and its surrounding ground in order to predict the thermal performance of a ground-source energy system. The two most vital parameters are the effective thermal conductivity of the ground and thermal resistance within the borehole. These measurement results are important for proper BTES design but also for commissioning and failure analysis. This method has significantly supported the rapid spreading of BTES systems and the introduction of this technology in “new” countries.

The overall objectives of Annex 21 are to compile TRT experiences worldwide in order to identify problems, carry out further research and development, disseminate gained knowledge, and promote the technology. Based on the overview, a TRT state of the art, new developments and further work are studied.

Official members of Annex 21 are currently: Canada, Finland, Germany, Italy, Japan, Korea, Sweden, Norway, The Netherlands, Turkey and Spain. Further, the following countries participate as observers: Argentina, Austria, Belgium, China, Switzerland and USA. Five experts meetings were held so far. The Annex will expire at the end of 2010.

For the complete objectives click - here - 48 kB .

If you are interested to participate in this Annex, or if you have related topics, publications, applications or projects which could be included in the work of this Annex, please contact Manfred Reuß

Applying Energy Storage in Ultra-low Energy Buildings (Annex 23)

Sustainable buildings will need to be energy efficient well beyond current levels of energy use. They will need to take advantage of renewable and waste energy to approach ultra-low energy buildings1. Such buildings will need to apply thermal and electrical energy storage techniques customized for smaller loads, more dis-tributed electrical sources and community based thermal sources. Lower exergy heating and cooling sources will be more common. This will require that energy storage be intimately integrated into sustainable building design. Many past appli-cations simply responded to conventional heating and cooling loads. Recent re-sults from low energy demonstrations, distributed generation trials and results from other Annexes and IAs such as Annex 37 of the ECBCS IA, Low Exergy Sys-tems for Heating and Cooling need to be evaluated. Although the ECES IA has treated energy storage in the earth, in groundwater, with and without heat pumps and storing waste and naturally occurring energy sources, it is still not clear how these can best be integrated into ultra-low energy buildings capable of being rep-licated generally in a variety of climates and technical capabilities.

Energy storage has often been applied in standard buildings that happened to be available. The objective was to demonstrate that the energy storage techniques could be successfully applied rather than to optimize the building performance. Indeed the design of the building and the design of the energy storage were often not coordinated and energy storage simply supplied the building demand what-ever it might be.

Responsible for this proposal of a new Annex is Fariborz Haghighat .

If you want to read the complete proposal click - here - 93 kB .

Material Development for Improved Thermal Energy Storage Systems
(Annex 24)

For the performance of thermal energy storage systems their thermal energy and power density are crucial. Both criteria are strongly depending, beside other factors, on the materials used in the systems. This can be the storage medium itself, but also materials responsible for the heat (and mass) transfer or for the insulation of the storage container.

After a number of thermal energy storage technologies have reached the state of prototypes or demonstration systems a further improvement is necessary to bring theses systems into the market. The development of improved materials for TES systems is an appropriate way to achieve this. The material solutions have to be cost effective at the same time. Otherwise the state of the existing technologies can not be brought closer to the market.

The world wide R&D activities on novel materials for TES applications are not sufficiently linked at the moment. A lot of projects are focusing on the material problems related to their special application and not towards a wider approach for TES in general. The proposed Annex should help to bundle the ongoing R&D activities in the different TES technologies.

If you want to read the complete proposal click - here - 34 kB

For more information contact Andreas Hauer .

Surplus Heat Management using Advanced TES for CO2 mitigation (Annex 25)

The world’s total energy supply is 136500 TWh/year whereas the energy use is approximately 94000 TWh/year (IEA Key Statistics, 2008). By inspecting these figures, one can see that close to 1/3 of the world’s energy supply is “wasted” in energy conversion. In reality, the number is even larger, perhaps as much as 50%, since for example the tank-to-wheel efficiency of engine driven transportation is only 20%, and boiler efficiencies seldom are above 90%. From a sustainability perspective, increasing the efficiency in many energy conversion processes is crucial. As the demand for energy increases in all sectors, and all over the world, waste heat management will be a cost-effective way of securing the supply of energy and power while mitigating the emissions of CO2. Such management is most effectively done in cases where the waste heat flow are large, like industrial processes, or in cases where the value of increases waste heat utilization is large, like in the vehicles and transporting goods sector. Recent advances in compact thermal energy storage has encouraged this initiative to explore solutions where waste heat management can be enhanced, facilitated and even enabled by integrating thermal energy storage technology.
The general objective of this Annex is to identify and demonstrate cost-effective strategies for waste heat management using advanced TES. New knowledge will be generated with regards to:

  1. The potential for advanced TES to minimize process waste heat through better process integration, enabling the use of waste heat for internal heating demands or cooling demands (via heat driven cooling).
  2. The potential for advanced TES to cost-effectively increase waste heat driven power generation in industrial applications.
  3. The potential for advanced TES to enable external use of heat from industrial-scale processes through effective thermal energy distribution.
  4. The potential for advanced TES to increase the utilization of waste heat in vehicles like on-board cooling and minimization of cold-start.
  5. The potential for advanced TES to increase the use of waste cooling (e.g., the large cooling potential associated with LNG regasification) and free cooling for comfort cooling applications.

Thus, a sub-goal of this proposed annex is to really dig into the waste heat utilization issue from a very broad perspective, and show the great potential for using advanced TES towards reaching a resource efficient energy system where waste heat (and cold) is minimized. This has a good potential for attracting a large number of participants from a variety of disciplines and levels of R&D (basic research to commercial systems).

If you are interested in this new Annex activity, please contact Luisa Cabeza .

Electric Energy Storage: Future Energy Storage Demand (Annex 26)

The future of electricity network involves a massive penetration of unpredictable renewable energies. For insuring network stability as well as for maximizing the energy efficiency of such networks, storage is a key issue. Up to now, the integration of renewable energies did not take into account the demand side and was performed in a “fit and forget” way. The optimum evolution in an economic perspective is in the future to have an integration that is respecting the needs. One solution – beneath demand side management and grid extension – is the use of energy storages. The main purpose of adding energy storage systems in the electricity grid is to collect and store overproduced, unused energy and be able to reuse it during times when it is actually needed. Essentially the system will balance the disparity between energy supply and energy demand. Worldwide between 2% and 7% of the installed power plants are backed up by energy storage systems (99% pumped hydro systems). The future demand of energy storage devices is actually unknown. Only the main influence factors on this demand are known.
The overall objective of this task is to develop a method or approach to calculate the regional energy balancing demand and to derive regional storage demand rasterizing the area and taking into account that there are competitive technical solutions. This objective can be subdivided into ten specific objectives:

  • To rasterize the whole area to typical small self-similar elements,
  • to identify and characterize typical fluctuating energy demand for different elements which stands for different regions and grid situations (e.g. intermeshing),
  • to identify and characterize typical fluctuating energy production (wind, PV) for different elements which stand for different regions and renewable energy potential (e.g. wind velocity),
  • to identify and characterize typical conventional energy production (gas turbine, nuclear power plant) for different elements which stand for different regions and conventional energy production,
  • to reduce different grid structures to a fistful typical systems and to simulate their inner intermeshing and their exterior connectivity (transport, import, export),
  • to derive balancing demand for each typical region,
  • to derive energy storage demand as a share of the total balancing demand, taken into account that the most successful economic solution will be realized,
  • to develop a method or model to transfer these results to other countries and regions,
  • to assess the technical and economical impact of energy storages on the performance of the energy system, and
  • to disseminate the knowledge and experience acquired in this task.

A secondary objective of this task is to create an active and effective research network in which researchers and industry working in the field of electric energy storage can collaborate.

If you are interested in this new Annex activity, please contact Christian Doetsch .

If you want to read more about the planned activities, please click - here - 266 kB .