First of all for those who may not know what electromagnetism is: the interaction of electric currents or fields and magnetic fields. What this means is that with certain metals you can conduct electricity though them to create a magnetic field.
Here is a simplified visual to help explain.
(http s://higgshunters.files.wordpress.com/2014/11/electromagnet.jpg)
Now if you may have already heard about engines that apply this area of physics you're probably already being a skeptic and saying perpetual motion engines are always going to be science fiction. True, as it stands they are. But that's not what this is. Instead what we have with electromagnetic engines is the release of potential energy created by the push and pull of the magnets. This is how you can have more output energy than input.
Current designs can be integrated into existing engines with only some modifications to engine blocks (see rough model below).
(http://sekouindustries.com/)
With a design like this you have a permanent magnet fixed in between 2 alternating magnets (see below for clarity).
(http://sekouindustries.com/)
The system operates on the same premise as current piston and crankshaft setups. Yet with this design you acquire a half stroke engine. For those who don't understand what a stroke is, it is the number of times a piston goes from top to bottom or vice versa. Current engines are 4 stroke, 1 down to pull gas into the chamber, 2 to compress it, 3 during the ignition and expansion of the gasoline, and 4 to expel the fumes out. So what does this mean for a half stroke you may ask? Using a half stroke means you get power out when the piston goes top to bottom and then back. Due to the alternating magnets each one will have a force exerted on it by the permanent magnet. The polarity of them will depend on the poles of the permanent magnet and the direction you want the piston to move.
As for making electromagnetic engines the future of energy, its possible to make each house independent or on a micro grid. Unfortunately that fact alone is why it will most likely not happen on the wide scale. But the technology is out there and available to people to learn more about as well as try to create for themselves.
If you like this post and wanna see more Science and Technology posts, drop me an upvote and or a comment with another topic you'd like to see me talk about. Another thing I am going to start doing is taking requests for things people would like to see made into a 3D model. Feel free to drop requests in the comments or shoot me a DM in steemit.chat 
~Tex