Shower Duration Cost Calculator

How much money goes down the shower? How do you know? Until you see utility bill, odds are you didn’t give it much thought. It’s an abstraction; buried deep in a multi-line-item statement.

Turn the handle off. Step out of the warm shower and wash away the day. But each minute under the showerhead come with a price tag.

How Much Does Your Shower Cost?

Here’s how that price tag gets calculated: You pay a certain rate for both energy and water. You use a certain amount of each. And you has to heat some of your water, which takes yet more energy. Everyone assumes a shower is cheap. They don’t really know the number, so they guess. A shower isn’t necessarily cheap. When you break down numbers, the math changes.

The first variable is flow rate. Some older shower heads spew out as much as three gallons a minute. That’s twenty-four gallons in an eight-minute shower. Big deal. Take an eight-minute shower. How many gallons does that equate to? Twenty-four with the old head, twelve with the new. Half the water. Plug in the time and the actual flow rate into the calculator, and it will do math for you, saving you the guesswork on volume conversions.

Water isn’t free. You’re paying for both the water itself as well as the sewer charge. And the sewer charge is frequently directly related to how much water you’re using. More water used = more sewer fees paid. The cost doubles. Often people ignore the sewer side of things. They see the water fee and they assume that’s all there is to it. There isn’t.

Oh yeah, then there’s all the heat. That’s when it gets expensive. Raising temperature of cold inlet water so you can take a comfortable shower requires energy. Natural gas or electric resistance doesn’t matter; it’s still just physics. To do this, you must consider how much of the cold inlet water need to be heated, and what the temperature of the cold inlet water actualy is. In winter, ground water will be close to freezing. In summer, it may be sixty degrees. The lower the temperature of the cold inlet water, the greater amount of energy needed to raise it to the temperature of a comfortable shower.

The calculator considers the temperature differential as well as your desired hot mix percentage. If you mix water in such a way that 60% of the water flowing through your pipes comes straight out of the hot water heater, and only 40% is cold inlet water, then you’re heating that 60% of the total volume of water. It use the principles of thermodynamics to estimate the number of therms (if using natural gas) or kilowatt-hours (if using electricity) necessary to get warm water out of your faucet. It also takes into account efficiency of your heater.

Efficiency is how well a heater performs. In other words, it’s an efficiency rating. So if you have a heater with a specific efficiency rating, a tankless unit has its own efficiency rating as well because it heats water on demand. However, a tank heater will lose it heat into the air. But it’s all about frequency. Sure, an occasional shower is no big deal. But three showers daily for a family of four are another story. And those add up in a hurry.

Let’s look at the cumulative effect here: What does a 20 cents-per-shower expense mean? Not much. But times it by thirty (days). Times that by twelve (months). Times that by four (people). What do you have now? That’s a pretty large expense, on par with running your fridge. See the reference table on the page. It helps show how various household habits scale.

Frequency vs. Duration. You’ll be surprised what a couple of minutes off a shower can save. Replace that high-flow showerhead with a low-flow one, and you’ll save even more. But there is a catch. A low-flow head can feel wimpy. Some folks adjust with longer showers. That’s counterproductive. The point is to lower overall heat and overall water usage. If you want to save money, an effective shower is a fast one, not a long luxurios soak.

Maybe the showerhead doesn’t spritz where you like. Perhaps you’re used to having lots of pressure. But amount saved in your bank account is very real.

And this thing helps you compare: It allows you to run through the numbers on how much it costs to keep doing what you’re doing now vs. It shows what it would cost to do something different and more efficient. It doesn’t tell you what to do. It simply presents the numbers. You decide.

Wasted water is wasted energy. It’s quiet. You don’t see it seeping from somewhere. You don’t smell it when it evaporates into the air or flows down the drain. You still pay for it. And it becomes a lot more interesting when you know what it costs. Because when you understand what parts make up that cost, you start seeing the shower differently. Water isn’t all there is. There’s also heated water. There’s water being brought to you and flushed away. There’s a price tag on that.

When you know what it is, you have the power to decide whether to change your ways. You can decide whether to upgrade the fixtures. Or decide whether to live with the price. Just do so with your eyes open. Next time you get in the shower, consider the gallons. Consider the heat. And then get out.