Table 2 Literature search

“Document Title”:(smart OR intelligent) AND (energy OR electricity OR heat*) AND (solution OR product OR technology OR service)

IEEE Xplore

137

acmdlTitle:(+(smart intelligent) + (energy electric heat) + (solution product technology service))

ACM Digital Library

66

TI (smart OR intelligent) AND (energy OR electric OR heat) AND (solution OR technology OR product OR service)

EBSCO

32

(TI = ((smart OR intelligent) AND (energ* OR electric* OR heat*) AND (solution* OR technolog* OR product* OR service*)))

Web of Science

26

(smart OR intelligent) AND (energy OR electric OR heat) AND (solution OR technology OR product OR service)

Science Direct

21