Since we have both the new Tesla 691HP dual motor all wheel drive Model S P85D as well as the previous 416HP single motor rear wheel drive P85 available for testing we decided to do a quick drive of mixed city and highway driving to compare the efficiency of the two.

During our 12.2 mile drive with both cars side by side driving normally with no hard accellerating or launching the P85 was clearly using less energy. Before the test both cars were charged to 100% with the P85D having a rated ranged of 243 miles and the P85 having a rated range of 254 miles.

Distance: 12.2 miles, city and highway

P85: 4.0 kWh (326 Wh/mi)

P85D: 4.7 kWh (388 Wh/mi)

For this short drive the P85 was about 15% more efficient than the P85D. This is interesting data since Tesla initially stated that the P85D would have 20 miles of range MORE the P85, then revised the numbers to 20 miles LESS than the P85. We’ve also heard there will be a software update from Tesla to address this issue by disabling the front motor when it’s not needed. Check out the pictures below for the data under “Since Last Charge”.