Abstract: Lighting of buildings is costly in terms of electric power, and in view of this, disclosure is made of apparatus and method for comparison of electric power usage with incandescent or HID, high intensity discharge, lighting source compared to an alternate lighting source, such as fluorescent tube lights, to give the same or adequate light reading on a light meter as attained by an incandescent or HID, high intensity discharge light source then measuring the ampere reading at the same voltage of each lighting source to determine the KW demand to further determine lowest lighting cost, which then in effect will equate to a virtual power plant, which can be a considerable saving of cost and reduction of atmospheric pollution.