Electric power is a practical reality and has many advantages for low speed boats for use on inland waterways. It is:
Really the only downside is that recharging a battery is not quite as simple as is pouring a few gallons of fuel into the tank. But with solar recharging, that's not a problem!
The cost of an electric drive is mainly in the batteries. However the total cost is not a lot more than would be a new diesel engine. After that, it's all saving!
This is covered in more detail in our information area