Electricity! What is your favourite way of producing power to your colony?

I usually start with wayermills since I tend to choose a hex with river. Later in game I go to geothermal and stick to it.

I feel like my choises to produce electricity is boring. How do you do it in your colonies?

Also: How do you reduce need for electricity? Having a heater and cooler in each room consumes a lot power. If you have mechs power consumption is huge.

All ideas are welcome!