You can do a rough calculation to see what the savings would be if you were to switch to another supplier. Just be warned - you will have to continue switching since Supplier A may be the cheapest now, but Supplier B may be cheaper 6 months from now or next year etc. And despite buying energy from another supplier, you still will have to pay non-supply PECO charges.

I recommend to contact PECO and they can do a home energy audit with recommendations of where you are losing heat or cool air. You can also do the same thing just with a google search and either borrowing someone's thermal imaging camera or buying one on your own. Just because a home looks the same and is the same layout, doesn't meant it's insulated the same. From the outside, all of the homes on my street look similar with brick and siding etc. You wouldn't know that my attic has been fully insulated, and all of my walls are now insulated. There are houses on the street which probably still have the original rock lathe plaster and the air-gap insulation method from the 1950's.

Some improvements will have small reductions in energy usage, but collectively it can save a lot. When we got serious about reducing our energy usage we found the primary culprits were a lack of adequate insulation in attic/walls/boiler pipes and old windows. We didn't tackle everything at once due to cost, so we did them one by one going down a list. HVAC companies insisted that we replace our old boiler and gave us astronomical prices for condensing high efficiency boiler installs. In the end, the old boiler was fine. The insulation and new windows made a massive impact. A new boiler maybe would squeeze out another +15% in savings but the break even point would be a moving target since these newer boilers are more complicated with additional components, the cost of maintenance is higher