This little 3700 powers why sump pump with ease when we lost power but it's main use is to power my espresso van! She runs everything from start up without pause allowing me to run Kei.Cup smoothly. It's quite enough to not disturb my customers over much. If I had followed the calculators I'd have a larger generator. I'm happy I took a chance on this little guy. In fact, I think it's still larger then I needed!