This text is about the use of solar energy for human needs, and is not just about photovoltaic. And although photovoltaic is not perfect: it is quickly becoming more effective and less costly.
Photovoltaic cells are becoming less dependant on rare-earth metals (which were predicted to ruin the photvoltaic market.) Among others, the Atawater Group at Caltech has been striving to increase solar efficiency and move towards metals such as zink and copper instead of rare-earth elements like Neodymium, Europium, and Dysprosium. An added bonus of using more common metals is that environmental damage could be reduced through their recycling (which is not 100% efficient, as we will discuss later), instead of the establishment or expansion of mines.
A great thing about the energy of the sun is that it is truly given to us without any need to extract it. The only environmental problems come from how we go about extracting, or then using, this energy from the light. You need far less equipment to use sunlight directly, without first turning it into electrical power. Solar energy is only a solution, in any form, if we also concentrate on finding more efficient, and intelligent, solutions to our problems.
Photovoltaic is comparable in price to natural gas if it is integrated into a smarter system (as a utility, instead of small, levels of generation). Still, the creation, installation, and maintenance of these panels themselves costs time, resources, and energy. Photovoltaic cannot outcompete the still growing market share of coal without environmental costs being reflected in the costs of operation.
The newest technology even allows transparent solar panels, which would allow you to even give your windows the capacity to generate electricity. The space used to generate power can thus be extended without being particularly noticeable (no more noticeable than glass).
Currently, companies are sworn to uphold the pursuit of profit, so why do many industries that go against the common good get subsidies so often? The answer likely lies in lobbying and an abdication of responsibility by lawmakers. Good examples would be factory farming or giant monocultures. I am sure you could go find at least a dozen examples in less than 10 minutes, whatever country you live in, if you really wanted to. It is also a fact that China spends the most on renewable energy than any nation and is, right now, building the infrastructure for more solar power than the U.S. has at all.
The fact is that the in almost every country in the world: coal power is still a standard and central pillar of energy policy. It is cheap, and releases more than just CO2 (coal is frequently contaminated with sulfur, lead, and other heavy metals). Despite coal’s use leading to China displaying a particulate matter index of approximately 10x the World Health Organization suggests to be safe, its use has (and will likely continue to) expand in both China and across the world.
The use of technologies like a solar still for obtaining clean water, solar cooking to prepare food, and optimizing the use of solar heating, can reduce electrical energy use, and thus overall consumption and dependency. You do not need to first turn the solar energy into electricity to use it to your benefit.
Moving away from coal is of the utmost importance, and not just because a coal mine being built right now in Australia threatens the Great Barrier Reef. Instead of governments allowing its expanded use and extraction, it is advisable for them to severely tax the process and put the money in research and education: making it truly too expensive and too dirty for anyone to be interested in pursuing.