The phrase "feasible alternative" means a possible solution or choice that is practical and achievable. It refers to an option that is realistic and can be successfully carried out. Full definition
We DO recognize the challenge here, but we are also painfully aware of the lack of feasible alternatives. (dotearth.blogs.nytimes.com)
The government will still support projects featuring high - efficiency technologies if «no other economically feasible alternative exists» or that utilize carbon capture technologies. (greentechmedia.com)
It is as if more or less feasible alternatives wait in the wings to challenge the present interpretation. (newscientist.com)