The Disadvantage of Solar Energy #3 is discussed on this page. Cadmium, which can be lethal to the environment is used in the production of solar energy panels.
The future disposal of exhausted solar panels will eventually be a Disadvantage of Solar Energy if the issue is not addressed before they reach the end of their life.
Currently many PV panels contain cadmium.
Cadmium is a metal that resembles zinc on many levels but lacks zinc's beneficial properties. Occurring naturally in only small amounts on the earth it is mostly a by product of smelting certain metals.
Leaching into eco systems through landfills and
A known carcinogen, cadmium is also the cause of "itai itai" disease which translates to english as "pain pain" disease.
Because cadmuim takes an extremely long time to break down it accumulates and builds up in eco systems and in biological specimens (like people).
In the human body Cadmium interferes with the absorption of important minerals.
Inhalation causes breathing and kidney problems frequently leading to death from
renal (kidney) failure.
When ingested (in sufficient quantities) it immediately damages the body's filters (kidneys and liver) rendering a body unable to filter toxins. A body cannot live long without functioning filters.
Solar Power is a good thing and we can make it even better by addressing issues before they become lethal.
Tons of solar panels have been installed on roofs worldwide. Residential solar power systems that are functional now shouldn't need replacement until they reach about 40 years of age. Plenty of time to produce a plan to ensure the safe disposal or reintegration of the cadmium.
While the cadmium is enclosed in a solar panel there is little concern of either inhaling or ingesting it. But, eventually there will be tons and tons of PV panels that need to be replaced and by then we'd better have a good idea about how to safely dispose of or recycle the cadmium.
To prevent the cadmium from entering our eco system, take retired solar panels to a recycling center or hazardous waste facility.