68. major impediment to the use of solar-powered products is the cost of solar energy and
that, given a choice, consumers would prefer products powered by solar energy over
those powered by energy derived from coal or oil. On the face of it, this assumption
seems acceptable; but it may be that there are other factors besides cost that make solar
energy less desirable than other forms of energy.
      In conclusion, this argument is convincing. To strengthen the argument additional
evidence indicating consumer preference for solar-powered products over products
powered by conventional forms of energy would be desirable.