Related Experiment Video
Updated: Aug 18, 2026

A Modeling and Simulation Method for Preliminary Design of an Electro-Variable Displacement Pump
Published on: June 1, 2022
Energy intensity of computer manufacturing: hybrid assessment combining process and economic input-output methods
1United Nations University, 53-70 Jingumae 5-chome, Shibuya-ku Tokyo, Japan. Williams@hq.unu.edu
Abstract:
The total energy and fossil fuels used in producing a desktop computer with 17-in. CRT monitor are estimated at 6400 megajoules (MJ) and 260 kg, respectively. This indicates that computer manufacturing is energy intensive: the ratio of fossil fuel use to product weight is 11, an order of magnitude larger than the factor of 1-2 for many other manufactured goods. This high energy intensity of manufacturing, combined with rapid turnover in computers, results in an annual life cycle energy burden that is surprisingly high: about 2600 MJ per year, 1.3 times that of a refrigerator. In contrast with many home appliances, life cycle energy use of a computer is dominated by production (81%) as opposed to operation (19%). Extension of usable lifespan (e.g. by reselling or upgrading) is thus a promising approach to mitigating energy impacts as well as other environmental burdens associated with manufacturing and disposal.
Related Concept Videos
Electrical Energy
Mechanical Efficiency of Real Machines
However, in reality, no machine can be truly ideal, and all of them experience some...
Power in a Three-Phase Circuit
Conservation of Energy in Control Volume
For steady flow systems, the time derivative of the stored energy becomes zero since there is no energy accumulation within the control volume. This simplifies the energy equation to:
Introduction to Partial Derivatives

