## 3 State of Technology  
In the following, the state of technology for the ACHP system using ammonia-water mixture as working fluid will be examined based on the experimental work carried out. The experiments conducted until 1994 were comprehensively discussed by [PERSON] (1997) [21] with an update of experiments until 2001 by [PERSON] (2005) [44]. Based on these results, Table 1 presents an updated overview of conducted experimental investigations. Figure 3: Simplified comparison of the described ACHP cycles in a ln p–1/T diagram (adapted from [PERSON] (1997) [18]). \begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline
**Author** & **Year** & **Cap.** & **T\({}_{\text{center}}\)** & **T\({}_{\text{stst}}\)** & **\(\Delta\)T\({}_{\text{stst}}\)** & **COP** & **Compressor** & & & & \\
**(Location)** & **Year** & **[kW]** & **[\({}^{\circ}\)C]** & **[\({}^{\circ}\)C]** & **[K]** & **[\({}^{\circ}\)]** & **Design** & & & & \\ \hline \multicolumn{10}{c}{**ACHP with single-stage solution circuit**} \\ \hline
**[PERSON] et al.** & 1983 & 15 & 24 & 59 & n/a & 4.9 & oil, recip. & n/a & n/a & [45] \\
**(Romania)** & 1983 & 4500 & 36 to 30 & 45 to 55 & 16.9 & 2.6 & dry, recip. & dry, recip. & s+t & Shell/tube horizontal & Shell/tube horizontal & [46, 47] \\
**Munic, Scheuermann** & 1984 & 160 & 60 to 45 & 25 to 78 & \(-\)5.6 & 11.3 & oil, recip. & Shell/tube horizontal & Shell/tube horizontal & [88] \\
**(Germany)** & 1987 & 15 & 40 to 15 & 40 to 70 & 28.1 & 4.3 & dry, recip. & s+t & Shell/tube vertical & Shell/tube vertical & [49] \\
**Munic** & 1989 & 1000 & 95 to 95 & 115 to 115 & 20.0 & 9.1 & dry, recip. & s+t & Shell/tube vertical & Shell/tube vertical & [50] \\
**(Germany)** & 1989 & 1000 & (const.) & (const.) & (const.) & & s+t & Shell/tube vertical & Shell/tube vertical & [51] \\
**Rane et al.** & 1989 & 7 & 15 & 45 & n/a & 3.7 & dry, recip. & s+t & Shell/tube vertical & Shell/tube vertical & [51] \\
**(USA)** & 1989 & 6 & 48 & 48 to 100 & n/a & 2.1 & oil, recip. & & & & \\
**Bakasas, Grandum** & 1999 & 60 & 48 & 48 to 100 & n/a & 2.1 & oil, recip. & Corrugated PHE & Corrugated PHE & [22] \\
**(Norway)** & 2001 & 13.5 & 42 to 27 & 42 to 57 & 15.2 & 3.7 & oil, recip. & Corrugated PHE & Corrugated PHE & [52] \\
**(North Ireland)** & 2003 & 27 & 43 to 35 & 60 to 72 & 27.0 & 4.3 & oil, twin screw, s+t & Corrugated PHE & Corrugated PHE & [53] \\
**(Germany)** & 2004 & 300 & 50 to 15 & 50 to 85 & 36.9 & n/a & oil, recip. & & & & \\
**(Norway)** & 2005 & 47 & 50 to 17 & 50 to 93 & 38.7 & 2.4 & oil, recip. & & & & \\
**([PERSON] et al.** & 2011 & 650 & 48 to 38 & 48 to 87 & 22.8 & 4.5 & oil, recip. & & & & \\
**(Norway)** & 2013 & 10 & 50 to 30 & 50 to 90 & 28.9 & 3.0 & oil, recip. & & & & \\
**(Republic of Korea)** & 2014 & 7.3 & 50 to 30 & 50 to 81 & 25.1 & 2.7 & s+t & Corrugated PHE & Corrugated PHE & [54] \\
**([PERSON] et al.** & 2019 & 40 & 59 to 49 & 50 to 60 & 1.0 & 2.5 & oil, twin screw, s+t & Corrugated PHE & Corrugated PHE & [56] \\
**(Germany)** & 2021 & 940 & 67 to 60 & 73 to 95 & 20.1 & 5.9 & oil, recip. & & & & \\
**(Norway)** & & & & & & & & & & \\ \hline \end{tabular}
\end{table} 
Table 1: Overview of experimental investigations on ammonia-water absorption-compression heat pump cycles.