A coaster type that's often overlooked in RCT2 is the powered coaster! A powered coaster is a coaster type which you can find in many real parks, where the train is propelled by motors inside the vehicles! You can usually recognize these coasters quite easily, because most of the time they have contacts on the track for the coaster to take electricity from, and usually there's a friction track on top of the track for a wheel to grip on to. Also, their layouts usually don't have any big hills, but usually consist of shallow slopes and helixes. Some of these rides, like Dragen at Legoland Billund also have a dark ride section!

In Rollercoaster Tycoon, the powered coaster is represented by the Powered Mine Ride! It is a train type where the train will automatically speed up until it has a speed of around 50 kmh! This coaster type is mostly made for families. For the layout of the ride, you should probably stick to shallow hills and helixes, and most of the ride thrills will probably come from the scenery you place around the ride, and interaction with paths or other rides! This is probably a perfect coaster type if you want to make a spooky park for Halloween! Some quick tips:

You can use diagonal track to stretch out your hills and make the angle less steep!
You can put the coaster in shuttle mode to make it reverse at a dead end! Be sure to put some brakes before the dead end though, or else the stop will be very sudden!
Trains for these rides can be very long, real ones usually have around 10 vehicles!
Most of the times, these rides will do several laps around the track.
You can control the speed of the train with brakes, chain lifts, or by changing the speed of the front vehicle with the ride vehicle editor plugin!