This is just common sense, G per watt in no way in hell is supposed to represent your total electrical usage. Be serious. Its the watts of your flower light and time it took to harvest compared to your dry weight. Everbody should be trying to cut back on there electric bill as this is common sense as well. To help cut back on electrical usage veg with cfl's. In flower make your dark period a little longer. If your that worried about your electric bill and sit down and calculate kwh then maybe you shouldnt be growing indoors or your just ocd about everything but growing your damn plant properly... Thats my opinion anyway.