Hi @mhherr
I think you’ll find that heating the water on your range top won’t really save you electricity. It will save you time though. Just one of those things when you’re dealing with thermodynamics - it’s going to take the same amount of energy to heat that water, regardless of the source.
The time savings is still nice. I use an electric kettle in conjunction with my Anova when I want to get my water to a high temp quickly (think creme brulee! 
).