The report describes some experiments related to the project Ekodrive, TA ČR TA0103012, which concerns with fuel consumption optimisation under condition of keeping the recommended speed. During control, a speeding risk can occur if designed control leads to a vehicle speed that is higher than speed limit. This problem is solved by switching to an additional (non-optimal) regulator and/or by using a deterministic logic control block whenever a speed limit overrun is predicted. Here, an alternative approach is proposed which uses an original controller only but the optimality criterion is extended by one terms that penalises vehicle speed increments.