Have you bought an Energy Star qualified appliance? Or an energy efficient heat furnace or air conditioning unit recently? The sticker says it’s energy efficient and give you statistics on how many Kilowatt Hours. per Year the appliance will use and how much it will cost. But how do you know for sure?
The answer is an Energy Monitor that will allow you to track your energy use in real time. Take for instance, the Blue Line PowerCost Monitor which can be easily installed on your electric meter outside the house. Once fastened, the sensor reads the amount of electricity that is being consumed real-time and wirelessly transmits the information to a hand held display unit. You track energy consumption by hour, day, week, month.
So back to the question of how do you know if you new energy star qualified appliance or HVAC unit really is as efficient as they say. To compare, you would take a baseline usage with the old appliance e.g. for an hour.
Then you would take the usage statistics with the new appliance. Make sure it a like for like comparison. The PowerCost Monitor should be accurate to with 5% of the actual usage. We recently had an HVAC contractor purchase the Blue Line Monitor so that he could demonstrate to his customers the before and after energy usage. The proof is in the pudding.