The title is misleading.

"Throughout this period, the system remained free of harmful by-products or sediment while achieving a 99.4 percent leak-proof efficiency. Even at high power outputs, it retained 78.5 percent of its energy efficiency, proving that the design is both reliable and durable."

99.4% leak proof against material transitioning within the membranes.

78.5% energy output efficiency.

And as others have said no useful metrics tbh.