Plans to combat global warming generally assume that continued use of coal for power plants is unavoidable for at least several decades. Therefore, starting as early as 2020, forecasters assume that carbon dioxide emitted by new power plants will have to be captured and stored underground, to cut down on the amount of global-warming gases in the atmosphere. Yet, simple as the idea may sound, considerable research is still needed to be certain the technique would be safe, effective and affordable.

What can we infer from the third paragraph?