Alternative Energy - what kind of impact?

There have been a few posts about alternative energy sources lately that have gotten me to wondering…

Some of the most popular renewable energy sources (or at least the ones the media likes to talk about) are solar, wind, and tidal. Each of these is supposed to be a good clean source of energy.

I understand that energy can’t be created, just converted from one form to another. Which means that in the case of the three sources listed above we’re taking some energy away from somewhere when we harvest sunlight, wind, or tides.

So I’m wondering what impact that loss of energy will have on the environment and/or climate?

For example, I read somewhere recently that an area 1/5 the size of Texas would, if covered in modern windmills, meet the entire energy needs of the US. But if we’ve got that many windmills taking energy from the wind, I imagine that there is considerably less wind on the leeward side of the wind farm. I would imagine that this would impact the local climate.

I imagine that stealing solar energy or tidal energy would also impact the local environment.

So far, only a very small percentage of our energy budget is from these three sources, and I’m sure that any impact has been small enough as to be virtually unnoticed, but what if we were to get all of our energy from one of these sources? Would the impact then be measurable?

Or have I somehow got my physics wrong?

For the most part it ends up as a recycling merry go round. Convert sunlight to heat water to heat your house to eventually end up back in the atmosphere. Harvest all the various kinds of natural energy, use it, and it eventually ends up back in the atmosphere.
Swapping BTU’s for Amps. to BTU’s etc.