Basically it's everything you may have been doing with Thermal Expansion before, generated via Thermal Expansion's Dynamos (the new engine type for TE). You can transmit RF via Tesseracts (which are now all-in-one per Tesseract: RF Energy, Items, and Liquids) or store the energy in the Energy Cells (like before, but with a few tiers of RF energy storage) and use those, but you need to connect to the machines with TE energy conduit to turn RF into MJ.
Several things already take RF natively as well, including MFR machines. The MFR BioFuel Generator will also output either MJ or RF (the ratio is 1MJ:10RF).
Quick example of how a Tesseract can handle a quarry now:
Touching lets it handle item transport (which goes back into my small AE system), the conduit connection is necessary to turn RF (which is produced by a battery of magmatic dynamos back at base and transmitted via the Tesseract)->MJ.
Also, if you're into steam boilers, you can use TE Steam Dynamos directly with boilers. They'll produce just like the Industrial Steam Engines in terms of throughput.