Table 1. Comparison of water consumption and electrical efficiency among AKL, PEM, and SOEC

Type of electrolyzer	Pure water consumption (kgH2O/kgH2)	Stack power consumption (kWh/kgH2)	System power consumption (kWh/kgH2)	References
AKL	N/A	51.30	N/A	[14]	Paper
	10.00	50.00	N/A	[21]	Commercial
	N/A	49.40	N/A	[22]	Commercial
	9.10	51.90	N/A	[23]	Commercial
	N/A	49.00	N/A	[24]	Paper
	N/A	56.50	64.00	[25]	Paper
	N/A	56.60	64.40	[26]	Paper
AKL Ave.	9.55	52.10	64.20	-
	N/A	55.60	N/A	[14]	Paper
	N/A	58.00	N/A	[24]	Paper
	N/A	56.50	66.50	[25]	Paper
	N/A	54.90	67.20	[26]	Paper
	10.00	53.20	N/A	[27]	Commercial
	N/A	55.90	N/A	[28]	Commercial
	13.00	49.90	N/A	[29]	Commercial
	N/A	54.60	N/A	[30]	Paper
PEM Ave.	11.50	54.83	66.85	-
	N/A	34.40	N/A	[13]	Paper
	N/A	39.20	N/A	[14]	Paper
	10.50	37.50	N/A	[31]	Commercial
	N/A	N/A	87.00	[32]	Paper
SOEC Ave.	10.50	37.03	87.00	-

1. System power consumption refers to the electrical power consumption that accounts for not only the stack but also the Balance of Plant (BOP) required to operate the stack.