Revisiting energy used to manufacture a desktop computer: hybrid analysis combining process and economic input-output methods

摘要

Using hybrid assessment that combines process and economic input-output methods, the total energy and fossil fuels used in producing a desktop computer with 17-inch CRT monitor are estimated at 7,320 Megajoules (MJ) and 290 kg respectively. This indicates that the network of industries for manufacturing computers is energy intensive: the ratio of fossil fuel use to product weight for a computer is 12, an order of magnitude larger than the factor of 1-2 for many other manufactured goods. In contrast with many home appliances, life cycle energy use of a computer is dominated by production (83%) as opposed to operation (17%). The yearly life cycle cost of owning a computer is about 3,000 MJ/year, half again that of a refrigerator, a much larger appliance that uses far more electricity in operation. The short lifespan of computers and the variety of computing needs of users suggests that extension of lifespan, for example by promptly reselling to users who need less computing power, is a promising approach to mitigating environmental impacts.