The results of the LCA (Life Cycle Assessment) analysis of electric cables revealed that over the full life cycle，cables cause greater CO₂ emissions when they are being used to conduct electricity than when they are manufactured. This CO₂ results from the generation of extra power necessary to make up for transmission losses. The only way of reducing these transmission losses，and hence CO₂ emissions， is to increase the size of the copper conductor as well as to raise voltages from 100V to 200V. The estimations based on the IEC standard showed that the life cycle cost of CV-T cables can be minimized by increasing the conductor siz e by a factor of two on average. Assuming that the CV-T cables used in Japan are entirely replaced in 20 years，the conductor size increases were found to reduce power loss by 35 GkWh per year，which corresponds to the capacity of four to five 1.1 MkW power stations. The replacement will also reduce CO₂ emissions by an unexpected 14.8 million tons per year，or as much as 1.17 % of the total CO₂ emissions in Japan of 1,261 million tons per year. Finally， authors have found out that these conductor size increases are more effective measure for CO₂ emissions reductions than the voltage raising to 200V.

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As the flame-retardants for eco-wise and cables synthesis-Mg（OH）₂ have been used widely. However this synthesis-Mg（OH）₂ is less ecological and costly，because a lot of energy are consumed in the synthesis process. This time, author has tried to replace synthesis-Mg（OH）₂ with natural-Mg（OH）₂，and has succeeded in improving the characteristics of natural-Mg（OH）₂ by crushing original stones to extremely small pieces and coating fatty acid onto those surfaces by dry method. And，by the detailed experimental results, it is clarified that the performance of the compound with natural-Mg（OH）₂ is nearly equivalent to that of the compound with conventional synthesis-Mg（OH）₂. In the next place，author has found out that it is possible to reduce the quantity of Mg（OH）₂ which is necessary to keep the compound flame retardant，by adding small quantity of red phosphorus. And also，it was verified by the LCA analysis that a lot of CO₂ emissions can be cut down by replacing synthesis-Mg（OH）₂ with natural-Mg（OH）₂ and reducing the quantity of Mg（OH）₂ by half. Additionally，author has made sure that the PH₃ gas from red phosphorus are harmless to the health，by researching the literature on that subject.

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