SummaryThe outlook for the extensive use of hydro‐electric power in the minerals industries presents a confused picture. In some areas in Canada hydro power is so abundant and so cheap it will defy competition for some time to come. In other areas, some of them critical mining areas, the low cost of hydro power is offset by limitations of size, convenience, and reliability. The latter areas seem to hold promise for more versatile sources of power such as diesel or nuclear.Diesel costs in these regions, however, are quite high. In large portions of northern Canada diesel power generating costs run well above 20 mills and, when full accounting is made for capital costs, the total may well run into the 3040 40‐mill range or even higher.Nuclear power which offers convenience above all, and freedom from fuel supply problems, appears to have excellent prospects in these regi