uneconomicaladjective
also uneconomic uk/ˌʌniːkəˈnɒmɪkəl/ususing too much money or too many resources and unlikely to make a profit:
Ethanol producers are seeing their profit margins squeezed and production may well become uneconomical.
(it is) uneconomical to do sth With oil prices high, companies have been returning to reserves that were uneconomical to extract during the years of low prices.