a
Princeton Environmental Institute, Princeton University, Guyot Hall, Washington Road, Princeton, USA
E-mail: elarson@princeton.edu
;
Fax: +1 609 258 7715
;
Tel: +1-609 258 4966
b
Department of Information Technology, Politecnico di Milano, via Ponzio 34/5, 20133 Milano, Italy
c
School of Energy and Power Engineering, North China Electric Power University, Beijing 102206, China
d
Department of Energy, Politecnico di Milano, via Lambruschini 4, 20156 Milano, Italy