What are the environmental, social, and economic costs of solar energy?
That depends on the type of “solar energy” you are using.
“Social costs” may be impossible to define in terms of energy sources. Economically all sources of solar energy are still more expensive than many alternatives. Solar concentration for heating water for steam electrical generation requires a large area. Solar photo-electric cells also require more space, but may be co-sited on existing buildings.
Photoelectric cells are constantly improving, but as yet they still incur a very large negative environmental cost due to the highly toxic materials used in their manufacture, as well as the energy required to manufacture them.
Reducing “fossil fuel” use and carbon dioxide production is an environmental positive, but that needs to be evaluated with respect to the other detrimental impacts their use entails.
“Passive Solar” energy can improve the environmental impact of building heating, but it cannot replace the existing heating methods for the desired level of comfort. Drying clothes in the sun is an age-old method (I still use it exclusively) that reduces the negative impacts from the use of heated dryer systems.