Like trains? There's Steamtown RR Museum in Scranton.
Steamtown National Historic Site (U.S. National Park Service), or a neat station in Jim Thorpe (Mauck Chunk).
Certainly architecture in these areas.
I believe there is a Mining (Coal) museum in Scranton (region is/was known for them).
Can't think of any hydro plants in the area unless you go south to Lancaster.
Delaware Water Gap is nice for fresh air.
Phila has architecture, the Art Museum, Franklin Institute, and several others around center city, but watch rush hour.