Yes the non-NAV version has a power flow diagram as well, but as Orcrone tried to point out in his reply it's not as informative as the NAV version. To quote him from one of his previous postings (under the "Upgrade to Nav Sys" thread, I believe):

[...] Also, the NAV version gives you more info. The energy consumption on the non-NAV just shows an engine, battery and wheels. It will show when the battery and/or the engine is driving the wheels. It will show when regen is charging the battery. But it won't show when the engine is recharging the battery. The NAV system will show a minute by minute breakdown of FE. It will show a minute by minute breakdown of battery regen. It has a resettable FE display that will hold your 'best' FE.