economical

using the minimum of time or resources necessary for effectiveness; "an economic use of home heating oil"; "a modern economical heating system"; "an economical use of her time"

of or relating to an economy, the system of production and management of material wealth; "economic growth"; "aspects of social, political, and economical life"

avoiding waste; "an economical meal"; "an economical shopper"; "a frugal farmer"; "a frugal lunch"; "a sparing father and a spending son"; "sparing in their use of heat and light"; "stinting in bestowing gifts"; "thrifty because they remember the great Depression"; "`scotch' is used only informally"