When can I use "since"?

[Tate]

Hello,
I don't quite understand when I can use preposition "since" to give reason for something. In the examples below I wanted to use "since" but it was replaced with "because" by the editor. I can understand nothing. Can you clarify the usage of "since"? Thank you very much.
1. But in this case, it would be incorrect to compare them (since) because small and large plants are oriented towards different customers and occupy different economy sectors.
2. Because (since)interest in the nuclear power is growing in the developing countries, activities in this area are reviving in many countries (USA, Japan, South Korea, China etc.).
3. Unfortunately, this plant was never commissioned (since) because the local population protested against it.

[Rover_KE]

Welcome to the board, Tate.

There's nothing wrong with your use of since.

A different editor wouldn't have turned a hair.

Rover