1 Subjects: “...energy efficiency index...”

2 Subjects: “...energy efficiency...”

3 Subjects: “...power conversion efficiency (PCE)...”

4 Subjects: “...energy efficiency...”

5 Subjects: “...environmental efficiency...”

6 Subjects: “...high energy efficiency...”

7 Subjects: “...efficient operation...”

8 Subjects: “...surface efficiency of the process...”

9 Subjects: “...efficiency...”

10 Subjects: “...efficiency...”

11 Subjects: “...energy efficiency...”

12 Subjects: “...energy efficiency...”

13 Subjects: “...tsunami efficiency...”