Range on current T600s is 120 miles at a constant 60 mph on a level highway, or 100 miles at 70 mph. One must deduct from that for hills, acceleration, etc.

We believe that a range meter showing % of battery remaining is the best method of displaying remaining range. Many OEMs try to predict the remaining range based on past driving habits. This is a very inaccurate way to figure range remaining, as past driving may have little to do with the planned driving ahead.

We recommend keeping in mind that you have roughly one mile of range at 70 mph for every % showing on your battery state of charge indicator. You can then deduct from that for hills, accelerations, and higher speeds.

For our production cars, we plan to offer 4 range options. They would be for 60 to 240 miles in 60-mile increments. Since the battery pack is a large part of the cost of a Tango, one can size it to meet one’s daily commute needs. The battery pack can also be switched out easily in the future for one with longer or shorter range if one's needs change.

Ideally, the battery pack will be rented, with the battery manufacturer responsible for the battery life rather than the Tango owner or lessee. The amortized cost of the battery pack and the electricity to charge it will be less than the cost petrol alone. Battery cost is roughly $5,000 per 60 miles of range. In order to have the lowest cost per mile, the battery should be sized appropriately. If one purchases or rents a battery that has twice the range of a typical commute, the cost of battery and electricity will be substantially less than the cost of gasoline.