I don’t know about you, but, when I feel the need for some extra comfort, I head to the bath tub. I know I’m not alone. There isn’t much that a good soak can’t wash away. If you’re feeling blue, or frustrated, or just exhausted, a few minutes with some bubbles, soothing music and a good book can make you a new person.
But, how hot is too hot? When it comes to water, you may find the numbers surprising. Most households use about 170L of water per day. That’s a heck of a lot of water! On top of that, most people’s hot water tanks are set much too high. If you can’t run your hand under the water without hurting, it’s too hot. Experts recommend 120F to prevent injury, but, 112F is hot enough to kill bacteria, and eliminate dirt. Your water should feel pleasantly warm, not hot.
Your hot water tank runs between 3 and 5 hours per day. Newer models aren’t quite as inefficient, but you get the picture. You’re heating a lot of water, and it just waits around until it’s needed. Not the most economical approach.
Water heating makes up about 20-25% of the typical natural gas use in a gas heated house in our type of climate. Lowering the temperature setting can cut your overall natural gas use by 5-6%. On a regular heating bill, that can be $20 or so a month. Not bad! |
Turning down the temperature setting of a storage tank water heater from 140F to 120F will save some energy, but nowhere near the 25% stated (except maybe in the case where absolutely no hot water is actually ever used), and nowhere near $20/month in any typical single home situation. Our own total monthly cost for gas consumed in the summer (for water heating and cooking, when the furnace does not run) is about $35. There is no way simply turning the water heater temp down 20F could/would cut that bill by over half. Turning down the temperature reduces "standby loss" - the heat lost by the water sitting in the tank (which is insulated), whether or not hot water is being used. The savings will have little relation to how much hot water is used. On a typical electric water heater, the monthly savings from a 20F tank temp reduction would more likely be in the range of 25 kWh. For a gas water heater, it would more likely be in the range of 5 Cubic metres.
ReplyDelete