One or two cents about this:
First, it's a question about efficiency. We can never convert hundert percent of any type of energy into usable energy. The second law of thermodynamics (I think, maybe the first one though, thermodynamics never was my strong point) forbids this.
Secondly it's a question about reliability. If our energy source is dependent on weather (which it is for now) we cannot solely rely on it. Of course, if we, say, would have solar panels or something just about everywhere on the planet, we could harvest solar light all the time, somewhere is always day and somewhere it will most likely always be sunny. The next questions in this hypothetical scenario would be about energy storage and transport. And here we will enter the question of efficiency again. We could build huge solar parks in African deserts, if we wouldn't have the sand problem, and try to get all that excess energy to Europe where it's needed. But the how to get it there is a huge problem. And ways to efficiently and effectively store energy are more or less limited too.
Thirdly it's about resources. Now I have no idea whatsoever what materials we need in solar panels and with what processes and kind of waste they're produced and how much energy that takes, but this definitely needs to be considered. It's like with e-mobility. The environment does not really win if the production of an e-car produces more waste and stuff than a petrol car produces in its ten years of usage. Hypothetically, I have no idea how this relation stands in reality.
Fourthly we have to consider also where the energy usually goes. If we would convert all the solar energy into electric energy and from that into artificical light and heat, what happens with the processes that are usually fuelled by the solar light? Here again, have I no idea about what's what, so I can't answer the question, but it does need to be considered. Just like with wind energy we need to consider what's happening with the weather if we take considerable energy out of the wind. Same goes with tidal and geothermal energy. I understand that a lot of sun light simply gets reflected on the atmosphere anyway, and if we could us that part somehow, then this would be no problem at all, but here we again get the transport problem if we ignore the cost and effort problems of how to get solar panels up there.