Excessive energy consumption has become a worldwide issue in today's design and manufacturing industry. An energy estimation framework that could later be used to integrate with CAD/CAM systems is in demand. This research develops a novel pattern to estimate energy consumptions. The pattern involves a software energy estimation framework and various software energy computational tools. Using this pattern, energy can be calculated by an energy estimation framework which can be attached with diverse energy computational tools. These computational tools can be designed for any purpose to calculate energy consumptions during a product life-cycle and for various manufacturing processes. The framework involved in this pattern features to be domain independent and flexible so that it will be expandable for different manufacturing domains and customizable for users. Details for developing such pattern are presented. Interaction between the framework and its computational tools is also discussed. With help of this pattern, energy estimation framework and energy computational tools can interact smoothly, and the development of computational tools can be extended or expanded for any purpose. Knowledge engineers who exert to integrate knowledge into computer systems can interpret domain-specific knowledge and share their expertise to improve the framework. The framework also assists users who have little knowledge about energy computations to estimate energy consumptions during the design stage, leading to products with reduced energy.