Abstract
Electricity consumption in the Internet, electronic network, in Japan was calculated with statistics for 1998. Methodologies to allocate the electricity consumption to each service provided by Internet were proposed. Then, electricity consumption and CO2 emissions associated with downloading 1 CD of music by Internet, especially, using dialup, were investigated. In addition, CO2 emissions associated with distributing 1 CD of music by ordinal compact disc were investigated and compared with those by Internet. CO2 emissions for downloading 1 CD of music by Internet were dependent on transmission speed, 0.79kg-CO2 if the communication speed is 64kbps (actual throughput: 51 kbps), and 0.16kg-CO2 if the communication speed is 1.5Mbps (actual throughput: 1.2Mbps). On the other hand, it was calculated that CO2 emissions for distributing 1 CD of music by ordinal compact disc was 0.33kg-CO2. CO2 emissions for downloading 1 CD of music by Internet will be reduced further with the increase in transmission speed.