What is a word for a person who uses resources to the maximum?
Solution 1:
Frugal
characterized by or reflecting economy in the use of resources ~ Dictionary.com
By being frugal, he's able to make his box of pencils last a very long time.
Economical
avoiding waste or extravagance; thrifty: ~ Dictionary.com
He is economical by nature. He can make a box of pencils last a year.
Solution 2:
thrifty
ˈθrɪfti
adjective
1. using money and other resources carefully and not wastefully.
he had been brought up to be thrifty and careful
(oxforddictionaries.com)