I haven't run either unit on the TI, but have operated the evolve
in both the drivewell (Pro Angler and Outback) and rudder (Outback) position. I've also operated it in several modes -- as a sole power source, in combination with pedaling, sailing and all three simultaneously. The performance characteristics of the evolve
followed the same pattern with both boats, only at a slightly different speed. The TI should follow suit here, but at higher speed.
Before getting into a discussion on performance, lets look briefly at a couple of ergonomic issues. From a physical point of view, the evolve
would seem to have a couple of critical advantages. 1. It can stow in the forward hatch when not in use. Where would you store the Torqeedo when not in use? How would you mount it and where (looks like it comes as a transom mount) 2. The evolve
operates remotely from your seat whereas the Torqeedo appears to require operation at the motor itself. If this is true, the Torqeedo 1003 might be impractical on the TI, regardless of power.
Now lets look at performance. A general guideline in kayak boat speed is that it every half knot increase in speed approximately doubles the power requirement. So if the Torqeedo 1003 has twice the power of the evolve
, it would be a mistake to think you'll gain much speed, and operating in such a fashion will reduce your range dramatically. Looking at the following graph, you'll see this was borne out with both the PA and Outback:
First note the greatly different power requirements and ranges at different speeds. The Outback range varied between 3.3 and 24.5 miles in the power-only mode, reaching a point of diminishing returns quickly above 4 MPH.
Note also, the power curve for the Pro Angler is almost identical. It runs about .1 to .2 MPH slower than the Outback for the same power input. You might expect the TI performance to mirror these at perhaps 1 to 1.5 MPH faster (depending on weight, configuration and environmental conditions)
Here's the result of an experiment from another forum member:
Because I had already made a 2 motor bracket for my Outback, I couldn't help but try using both 30lb thrust trolling motors. I took my GPS with me so I could record my speed. With both motors running on high (5th speed) the best my empty Qutback could manage was 4.6 - 4.7 mph. Next I tried using only one motor and the speed was 4.3 - 4.4 mph. Obviously, using 2 motors would deplete the battery twice as fast as one and I only gained a couple of tenths at best over using a single 30lb trolling motor.
In looking at range parameters with the TI, it's realistic to note that an electric motor is one of only three power sources. Operating your electric motor concurrently with sail and/or pedal power has an enormous impact on range and/or a modest impact on speed if desired. The scenario where two Mirage Drives and a sail all fail is extremely unlikely. The chart above will at least give you some clues as to what to expect using hybrid power (blue line compared with the green line).
Bottom line is, twice the power will not give you any additional speed without reducing your range accordingly. Doubling your battery storage will double your range at the same speed. Changing your speed strategy and/or running the electric motor along with another available power source can have a greater effect on your range than battery capacity.
This may not answer your question entirely, but hopefully it will give you some points to ponder in deciding between the Torqeedo 1003 vs evolve