Green software use on HPC: Key Points

Introduction

Electricity is a proxy for carbon, so building an application that is energy efficient is equivalent to building an application that is carbon efficient.
Green software takes responsibility for its electricity consumption and is designed to consume as little as possible.
Quantifying the energy consumption of an application is a step in the right direction to start thinking about how an application can operate more efficiently. However, understanding your application’s energy consumption is not the only story. The hardware your software is running on uses some of the electricity for operational overhead. This is called power usage efficiency (PUE) in the cloud space.
The concept of energy proportionality adds another layer of complexity since hardware becomes more efficient at turning electricity into useful operations the more it’s used.
Understanding this gives green software practitioners a better insight into how their application behaves with respect to energy consumption in the real world.