By using "renewable" energy sources, we are in fact depleting the Earth from one form of energy (wind, solar, ...), producing some work (mechanical, thermal, chemical, electrical, ...) and, usually, dissipating heat. There are some directly affected climate processes. For example, if you cover a big area with solar panels, the ground does not get heat up, which can have an effect in water reservoirs or whatever.
So, this is happening when we use renewable resources. I assume we can agree on this.
But there are a couple of caveats:
- probably the scale at which we are currently affecting the environment with renewable energy sources is reaaally small, specially compared to the effect that non-renewable energy sources have. But anyway, exponential growth based on renewable energy sources will at some point start having a big effect on climate too. This is probably very far way, and we can probably compensate for this somehow (terraforming Earth, so to say). As long as we are using up a small fraction of the sun energy, we have room for maneuver. An even then, nuclear energy can help further, so the ultimate limit is the amount of matter we have at our disposal.
- it is difficult to say how Earth adjusts to this tampering: is it able to dissipate the heat produced by human processes (not talking about CO2 here)? Is it able to absorb more sun radiation, since the "equilibrium situation" has been affected? I mean, if we "slow down the wind" with a wind-turbine, maybe there is a new complementary process which takes care of putting sun energy in the wind again.