What Is an adjective meaning using minimum of resources?

Here are some adjectives that mean using a minimum of resources, depending on the specific nuance you're looking for:

General:

* Economical

* Efficient

* Thrifty

* Frugal

* Minimalist

* Spartan (implies a basic, austere style)

More specific:

* Resource-efficient

* Cost-effective (focuses on financial resources)

* Energy-saving (focuses on energy resources)

* Sustainable (emphasizes long-term impact and resource conservation)

* Lean (used in business contexts to describe a company or operation that runs with minimal resources)

The best adjective for you will depend on the context and the specific kind of resource you are referring to.