@Electric_Magic it sounds like there's something wrong with your steam set up. You should be able to make some kind of power if everything was working properly. Clutch slippage is also very important too. The final clutch before the generator needs to be somewhere around 0.40-0.55 to keep from having too much drag on the flywheels. Mass of the flywheels is also important, I find the 3x the mass of the generator is important for producing a lot of power consistently.

I'm really unsure why it produces such a steady output, I feel like i have or have had all the same things on mine, and i've made 1200 swatts so far but only for a second before it tapers back to zero

Sure just be sure to link what you've made with it in the comments. I'd love to see what you make!

Can I use it?

This is just an electrical generator.

Is this an electrical generator? or just an Engine?