Project highlights Advanced Thermal Management

SoC4PCM

AI-Based Acoustic State-of-Charge Detection for Latent Heat Storage Systems

Latent heat storage systems (PCMs) play a critical role in enabling the efficient use of fluctuating renewable energy sources such as solar and wind. However, accurately determining their state of charge (SoC) remains a significant technical challenge: during the phase change process, the temperature of a PCM remains nearly constant, making conventional temperature-based measurement methods ineffective.
The SoC4PCM project addresses this challenge with an innovative acoustic approach. Short ultrasonic pulses (chirps) are transmitted through the storage tank from the outside. Because sound propagates differently in solid and liquid phases, both the signal transit time and reflection patterns vary depending on the material’s current melt fraction.
An AI-driven analytics system interprets these acoustic signals to reconstruct the spatial distribution of solid and liquid regions across the entire storage volume. Based on this information, the system determines the state of charge with high precision.
The trained model operates entirely stateless, calculating the SoC directly from real-time acoustic input—without requiring historical operating data. The ultrasonic sensors are mounted non-invasively on the exterior of the storage tank using adhesive or magnetic fixtures, allowing seamless integration into both new and existing systems without structural modifications.
Initial testing has demonstrated an accuracy of over 97%. The calculated state of charge can be directly integrated into higher-level energy management systems or heating control units, enabling optimal utilization of storage capacity while minimizing energy losses.

This technology is suitable for a wide range of applications, including building energy systems and industrial thermal storage processes.

Funding body: BMWE, funding code: KK5654703CM4
Duration from: February 1, 2025 to January 31, 2027

ELa

Energy-saving glaze with stabilized silver nanowires for transparent low-e wall coatings

The aim of the project is to develop a transparent, low-emissivity (low-e) energy-saving glaze based on stabilized silver nanowires. This glaze can improve the insulation performance of buildings by up to 25% with virtually no change to the visual appearance of the color, by significantly reducing heat radiation from wall surfaces due to its low emissivity. For this purpose, the glaze is specifically applied to the interior side of exterior walls (exposed concrete, plaster, etc.), particularly in older buildings.
The resulting product, which is to be marketed in the future under the name HeiQ Xpectra by the project partner HeiQ RAS AG, received the “German Sustainability Award 2026” for products in the Climate Transformation field. The award recognized its “[…] ability to make a significant contribution to energy savings and emission reductions with minimal material use and effort […]”.

Funding body: BMFTR, funding code: O3DPS12O8A
Duration from 01.09.2024 to 28.02.2026

White surfaces on facades and roofs, as often found in southern countries, heat up little during the day when exposed to sunlight.

PaRaMetriC

Passive radiation cooling

Almost 20 % of the global electricity consumption is caused by cooling systems. As the demand for cooling is expected to grow tenfold by 2050, improving the efficiency of cooling systems plays a critical role in addressing the global climate challenge.
Passive Radiative Cooling (PRC) materials, which can dissipate heat into the surrounding as thermal radiation (especially through the atmospheric infrared window between 8 µm and 13 µm) have recently emerged. Hence, the EU-project PaRaMetriC (Metrological Framework for Passive Radiative Cooling Technologies) aims to develop a comprehensive metrological framework with standardized performance indicators and testing protocols to enable comparable evaluation of their cooling performance on-site and the determination of potential energy savings that could derive from the deployment of such technologies.

EU funding code: 21GRD03 PaRaMetriC
Duration from 01.10.2022 to 30.09.2025
The project 21GRD03 PaRaMetriC receives funding from the European Partnership on Metrology, co-financed by the European Union's Horizon Europe Research and Innovation Programme and from the Participating States.

Hi-TRACE

Industrial process optimization through improved metrological methods for determining thermophysical properties. Many industries, such as aerospace, power generation, and glass and ceramics, operate equipment at temperatures above 1500 ºC. In order to optimize these processes, improve energy efficiency and increase competitiveness, new, more temperature-resistant materials are being developed for which precise knowledge of the relevant parameters under the operating conditions is necessary. The aim of the project is therefore to create a metrological infrastructure to provide traceable measurement data of thermophysical properties such as temperature Tf, contact resistance Rc, thermal diffusivity a, heat capacity Cp and emissivity up to 3000 ºC.
This includes the development of highly accurate reference equipment, new measurement techniques, reliable calibration methods, validated uncertainty budgets, and traceable reference materials for the high-temperature range for the determination of thermal and infrared optical properties as well as for the non-contact recording of the adhesion properties of coating systems.

EU funding code: 17IND11 - Hi-TRACE
Duration from 01.07.2018 to 31.12.2021
This research was funded by EMPIR program co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation program (funding code 17IND11 - Hi-TRACE).