The current Teleporter needs 3million Eu for every Teleport, which is much, but for far distances understandable. But what if you want (for whatever Reason) a Teleporter which teleports you just 50 blocks away? Well then 3million Eu is really much. So heres my Suggestions:
Make the Teleporters Energy usage depends on the distance. As example:
Teleporter 1 is at x= 100 y=70 z=100 and teleporter 2 is at x=600 y=65 z=300
So the math is:
Differenc of T1 x and T2 x=600-100=500 distance for x
Same for z and y which would be z=200 and y=5 together that is 500+200+5 =705 distance. If lets say the Teleporter needs 1.000 EU for each distance point. So it would be 705.000 EU (of course the amount per distance point can be changed due to balance).
I dont know much about Coding but i think this isnt hard to make because computing is all about Numbers and Maths.
Alternative is could be a system like:
0-100 Distance = 200.000 EU 101-300 = 500.000 Eu ...
Well the exact Numbers are up to you but i think you got ma Idea.
Edit: Sry, wasn't informated. My suggestion is useless delete or so.