What type of quarry are you using, and how big is your reactor (power and fuel usage)? As well, how are you processing your yellorium ore?
In my Infinity world I built a medium-sized reactor and powered a Speed III Ender Quarry in a Mystcraft flat age (normal ore density) with it, along with the rest of my base and ore processing, and I ended up raking in a pretty massive surplus even before I converted it into active cooling (I did have other power generation but it was less than 10% of the total power).
If you are running a deficit I suspect that either the Direwolf20 pack nerfs Big Reactors more than Infinity does, your reactor design is inefficient, or your quarry is using significant less power than the total your reactor is producing (either due to you having other even larger consumers or if you are storing all the excess energy).
The other option I would recommend is bees, since they produce renewable yellorium for free (once you obtain the bees, set up the apiaries and automate them, most likely with pipes). Unlike a quarry, you never have to touch the bees once set up properly. On the other hand, Ender Quarries don't seem to have a limit for the quarry area. Mark off a 1024x1024 area and even a Speed III Ender Quarry will run for several real-life days, yielding hundreds of thousands of yellorium ingots. A passively cooled reactor that is reasonably designed and sized to power the Speed III quarry (~30kRF/t) will take several real life months to consume that yellorium, so there's no rush to reset the quarry when it does finish. Convert it to actively cooled and build turbines and you'll be able to power whatever toys you can think of with the same reactor.
For example, in my world, I sized my Big Reactor such that, when passively cooled, peak efficiency is reached at around 70% control rod insertion, producing 30kRF/t with less than 2mb/t of yellorium. When converted to active cooling, that changes to 15B/t of steam, but you can then pull the control rods out and get close to the 50B/t limit off of 5mb/t of yellorium. With ludicrite turbines that comes up to roughly 700kRF/t. A Speed III Ender Quarry (consumes ~30kRF/t) should be pulling up enough yellorium to theoretically run more than a dozen of these guys, assuming my numbers are right. That's over 8000kRF/t of production off of a 30kRF/t quarry + processing line.