solution for energy raw material is not disturbing human food supply

between the energy raw material their are
disturbing food supply for human other between
that is
 cassava
 wheat flour
banana
sorghum
rice
cane sugar
red sugar
dates

then how a solution so as not to interfere human food supply needs
the researches began researching the new source of energy 
other betweeen
alga biofuel 
 wood biofuel
plastic oil(oil making from plastic