When I connect an EnderIO capacitor directly to the steam turbine it will pull >10k rf/t from the turbine. Didn't see this behavior using Immersive Engineering cables or the cables from Industrial Renewal.
Tried connecting the turbine to an industrial battery bank using EIO conduits with the same result. No problem with IE or IR cables here either.

I think it's because the EnderIO conduit mechanics of both extracting and inserting energy in the same conduit at the same time. The turbine is meant to have it's buffer extracted only, but EnderIO conduits also attempts to inject energy into the buffer system, which would cause a positive feedback loop providing unlimited free energy. As long as you don't use EIO conduits, the bug would cease to exist. We had this issue in one of the modpacks, so we just removed the conduits entirely to prevent bug exploitation.

You could confirm this by telling EIO conduits to not insert energy into the buffer. If I had used steam turbines by now I'd also try to confirm that suspicion.