Porsche to go super hybrid

70 mph on the electric engine alone

Porsche has announced plans to develop a Porsche Cayenne hybrid that will be 25 percent more fuel efficient than a conventional Cayenne. More interesting, however, the hybrid Cayenne will be able to cruise on pure electricity up to 70 mph. Toyota hybrid vehicles, for example, can only drive in all-electric mode up to around 30 mph.

So, what is Porsche's secret? I wish I knew.