10km is about right. That's was commute to school back then. It's more about getting the engine up to operating temperature. The bare minimum threshold needs to be reached before the engine will shut off (and thus complete its warm-up cycle) but it won't be near the preferred temperature. Nevertheless, I wouldn't worry too much about it. 10km is sufficient. Read this if you're interested to know the details. It's for the 2nd generation Prius so some of the computer logic might be slightly different but the basic concept is the same. The Five Stages of Prius Hybrid Operation | PriusChat
Cheers for the info that link is very interesting! 1 question we have 1 garage at home and normally the wifes car stays in there as she has the nicer car. Does a hybrid battery last longer if it is kept inside a garage? Or is it my turn to use the garage??
The Hybrid Battery already lives in a Garage [also known as the passenger compartment] , it is tucked snugly into bed under the rear seat The day that you get snow in South Auckland ,would be more of a concern [along with Hell freezing over]