It looks like those sparks can pack quite a punch. Instead of just setting a chunk of iron near the spark, this time I punched a hole in the middle of an ingot so that it could spin like a propeller, and then set it down near the spark.
A single spark on a reasonably small amount of red rock spun that heavy chunk of ingot for a good long time.
So I’m thinking I can use this to power a rail system.
The biggest problem will probably be that the rails where the electricity is running will have to be much more conductive than iron, especially if I want them to do things like go up hill.
On the other hand, even on relatively flat land it looks like a medium amount of red rock should be enough to move a cart a reasonably long distance, even if I build the cart out of iron.
(And let’s face it, an iron cart of reasonably thin walls is going to be more durable and possibly lighter than its counterpart in wood. Less kaboom from the giraffe-corgis.)