## 3 Thermochemical Heat Storage: Description of Materials and Processes
### Thermochemical Heat Storage Systems
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Project Name/Institution** & & **Description** & **Storage System** \\ \hline \multirow{8}{*}{SWEAT 1/ECN [229] (2004)} & \multirow{8}{*}{\(\bullet\)} & Solid sorption storage for cooling purposes. & \multirow{8}{*}{Na\({}_{2}\)5/H\({}_{2}\)O} \\  & \(\bullet\) & T\({}_{\rm c}\) = 15–25 \({}^{\circ}\)C & \\  & \(\bullet\) & T\({}_{\rm d}\) = 77–86 \({}^{\circ}\)C & \\  & \(\bullet\) & Thermal power measured in discharging mode & \\  & \(\circ\) & 0.5–0.7 kW & \\  & \(\bullet\) & Thermal power measured in charging mode 1.2 kW. & \\  & \(\circ\) & Solid sorption storage for cooling and & \\  & \(\bullet\) & heating purposes. & \\ MCES 2 [242] (2004) & \(\circ\) & T\({}_{\rm c}\) = 65 \({}^{\circ}\)C & \\  & \(\circ\) & T\({}_{\rm d}\) = 80–95 \({}^{\circ}\)C & \\  & \(\circ\) & Storage energy density 8 MJ/kg. & \\  & \(\bullet\) & Storage system for heating purposes & \\  & \(\bullet\) & T\({}_{\rm c}\) = 25 \({}^{\circ}\)C & \\ MODESTORE [141; 307] & \(\bullet\) & T\({}_{\rm d}\) = 88 \({}^{\circ}\)C & \\ (2006) & \(\bullet\) & Thermal power measured during discharging mode & \\  & \(\circ\) & 0.5 kW & \\  & \(\bullet\) & Thermal power measured during charging mode 1 kW. & \\  & \(\circ\) & Solid sorption storage for heating and & \\  & & cooling purposes. & \\ SOLAR-STORE [278] (2008) & \(\circ\) & T\({}_{\rm c}\) = 35 \({}^{\circ}\)C & SrBr\({}_{2}\) with expanded \\  & \(\circ\) & T\({}_{\rm d}\) = 80 \({}^{\circ}\)C & natural graphite \\  & \(\circ\) & Heating density power 47–49 kWh/m\({}^{3}\) & \\  & \(\circ\) & Cooling density power 27–36 kWh/m\({}^{3}\) & \\  & \(\bullet\) & Solid sorption storage for heating and & \\  & & cooling purposes. & \\ SOLAR-STORE [278] (2008) & \(\bullet\) & T\({}_{\rm c}\) = 35 \({}^{\circ}\)C & \\  & \(\bullet\) & T\({}_{\rm d}\) = 80 \({}^{\circ}\)C & \\  & \(\bullet\) & Heating power 60 kW & \\  & \(\bullet\) & Cooling power 40 kW & \\  & \(\circ\) & Solid sorption storage for waste heat & \\  & & industrial recovery & \\ Fraunhofer [136] (2012) & \(\circ\) & T\({}_{\rm c}\) = 30 \({}^{\circ}\)C & Zeolite/CaCl\({}_{2}\) \\  & \(\circ\) & T\({}_{\rm d}\) = 9–200 \({}^{\circ}\)C & \\  & \(\circ\) & Heat storage capacity 0.54–0.79 MJ/kg & \\  & \(\bullet\) & Storage system for dwellings & \\ E-hub/Project [190] (2012) & \(\bullet\) & T\({}_{\rm c}\) = 85–88 \({}^{\circ}\)C & Zeolite \\  & \(\bullet\) & Heat density power 164 W/kg. & \\  & \(\circ\) & Lab-scale prototype for space heating & \\ E-hub/Project [189] (2014) & \(\circ\) & T\({}_{\rm c}\) = 20–30 \({}^{\circ}\)C & Zeolite 5A \\  & \(\circ\) & T\({}_{\rm d}\) = 80–120 \({}^{\circ}\)C & \\  & \(\circ\) & Storage energy density 0.045 GJ/m\({}^{3}\) & \\  & \(\bullet\) & Solid sorption system for space heating and domestic & \\ COMTES 3 [309] (2015) & \(\bullet\) & T\({}_{\rm d}\) = 75 \({}^{\circ}\)C & Zeolite 13 XBF \\  & \(\bullet\) & Storage energy density 0.4 CJ/m\({}^{3}\) & \\  & \(\circ\) & Liquid sorption system for diurnal storage & \\ COMTES [163] (2015) & \(\circ\) & T\({}_{\rm d}\) \(>\) 50 \({}^{\circ}\)C & NaOH/H\({}_{2}\)O \\  & \(\circ\) & Power output approximately 1 kW & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Example of prototypes of closed systems for thermochemical storage.