Periodic Reporting for period 2 - THERMOBAT (A Ferrosilicon Latent Heat Thermophotovoltaic Battery)
Periodo di rendicontazione: 2023-06-01 al 2024-11-30
The availability of cost-effective energy storage technologies with durations from 10 h to several days is key for variable renewable energy sources to become major contributors to electricity generation. In upcoming years, battery prices are expected to remain too high, with energy storage as heat emerging as a cheaper and more promising solution. Even if there is an efficiency penalty in converting heat back to electricity, the low cost of heat storage is a big advantage, especially because this conversion is not always necessary, since heat accounts for about 50% of global energy demand.
Latent heat thermophotovoltaic batteries allow for much lower cost than state-of-the-art electrochemical batteries and can provide both heat and electricity on demand, which make them attractive for grid-scale, long-duration energy storage, and distributed dispatchable cogeneration. This project will develop the first latent heat thermophotovoltaic battery and will demonstrate the technology in a relevant environment for combined heat and power dispatchable generation.
Latent heat thermophotovoltaic batteries allow for much lower cost than state-of-the-art electrochemical batteries and can provide both heat and electricity on demand, which make them attractive for grid-scale, long-duration energy storage, and distributed dispatchable cogeneration. This project will develop the first latent heat thermophotovoltaic battery and will demonstrate the technology in a relevant environment for combined heat and power dispatchable generation.
Objective 1: New route for manufacturing FeSiB PCMs from raw and waste materials at cost lower than 3 €/kWh
This objective is being addressed in WP2. More than 100L of FeSiB have been produced using cheap raw materials. Moreover, the Si, B and Fe resource mapping has been elaborated, which is key to understand the cost of the manufacturing of this new PCM.
Objective 2: 100 kWh Heat Storage Box with > 1 MWh/m3 withstanding > 100 thermal cycles
This objective is being addressed in WP2. Small scaled sealed crucibles incorporating protective coatings have been developed. Experiments have confirmed the capability of 100 thermal cycling. Next step is to corroborate that this result is reproducible and can be extrapolated to larger scale sealed crucibles.
Objective 3: 1 kW TPV generator with an efficiency > 20 % and power density > 1 W/cm2 at 1200ºC
This objective is being addressed in WP3. A Germanium TPV cell have been developed with an efficiency of 11.2% and a power density of 1.4 W/cm2 under a graphite emitter at 1544ºC. Simulations suggest that efficiencies approaching 20% are attainable in practice. The first TPV module of 100 W electrical power capacity has been developed.
Objective 4: A 100 kWh LHTPV demonstrator with electric-RTE > 10 % and global-RTE > 70%
This objective is being addressed in WP4. During the first year of the project, the electric furnace was developed. Also, a new cooling approach has been developed and investigated experimentally. This new approach addresses some relevant safety issues of the original design. Moreover, the innovative character of this solution adds value to the technology, as it may generate new intellectual property rights not previously anticipated in the DoA. The different components are being integrated in the furnace.
This objective is being addressed in WP2. More than 100L of FeSiB have been produced using cheap raw materials. Moreover, the Si, B and Fe resource mapping has been elaborated, which is key to understand the cost of the manufacturing of this new PCM.
Objective 2: 100 kWh Heat Storage Box with > 1 MWh/m3 withstanding > 100 thermal cycles
This objective is being addressed in WP2. Small scaled sealed crucibles incorporating protective coatings have been developed. Experiments have confirmed the capability of 100 thermal cycling. Next step is to corroborate that this result is reproducible and can be extrapolated to larger scale sealed crucibles.
Objective 3: 1 kW TPV generator with an efficiency > 20 % and power density > 1 W/cm2 at 1200ºC
This objective is being addressed in WP3. A Germanium TPV cell have been developed with an efficiency of 11.2% and a power density of 1.4 W/cm2 under a graphite emitter at 1544ºC. Simulations suggest that efficiencies approaching 20% are attainable in practice. The first TPV module of 100 W electrical power capacity has been developed.
Objective 4: A 100 kWh LHTPV demonstrator with electric-RTE > 10 % and global-RTE > 70%
This objective is being addressed in WP4. During the first year of the project, the electric furnace was developed. Also, a new cooling approach has been developed and investigated experimentally. This new approach addresses some relevant safety issues of the original design. Moreover, the innovative character of this solution adds value to the technology, as it may generate new intellectual property rights not previously anticipated in the DoA. The different components are being integrated in the furnace.
The key innovations fo the project are: 1) novel ferrosilicon-based PCMs that can be produced from low cost raw materials, 2) a crucible concept that can contain the PCM and widsthand a large number of thermal cycles, 3) a TPV cell and generator that efficiency converts heat into electricity, and 4) the complete LHTPV battery that can store surplus of renewable electricity and produce heat and electricity on demand. So far, most of the results have been obtained regarding the first three items. Moreover, we have started a working group to define an strategy for the upscaling and commercialization involving the key industrial actors.