For the purpose of Chapter 70 the following words shall be construed to mean as follows:

(1) A kilowatt hour shall be deemed and considered to equal one thousand watts, or the energy resulting from an activity of one kilowatt continued for one hour, which equals about one and one-third horsepower hours;

(2) The word watt shall be construed to mean the practical unit of electric power, activity, or rate of work equivalent to 107 ergs or one joule per second, or approximately one seven-hundred-forty-sixth of a horsepower.