Answer:
The energy follows the concept of thermodynamics and cannot violate it. The energy can neither be created nor be destroyed, it is already present in the nature. The energy can be converted into the different forms.
The researcher claims that plant can produce twice energy as it harnesses from its environment. This is not possible as it works against the laws of thermodynamics. The second law of thermodynamics is violated here as the energy transform but it gets wasted more and more. The randomness of the system increases in the universe.