[1] Department of Industrial Engineering, University of Florence, Firenze FI,50134, Italy
[2] Instituto Universitario de Investigación CIRCE, Fundación CIRCE, Universidad de Zaragoza, Zaragoza,50009, Spain
[3] Research Centre for Energy Resources and Consumption (CIRCE), Zaragoza,50018, Spain
[4] Reykjavik Energy, Bæjarháls 1, Reykjavík,110, Iceland