The Inalienable Right– Hot Water


Whether by means of a furnace coil, electric tank, gas fired tank, tankless (see last post) heater, or other device, every American home is expected to supply enough hot water to: bathe every member of the household at least once a day to his/her satisfaction, run two loads of laundry through an automatic washer, operate the dishwasher at least one cycle, and supply hot water at each tap for the washing of hands/dishes/faces/toothbrushes.

Hot water needs run from 15 to 30 gallons per day per person, accounting for about 30% of a household’s energy consumption. Other major energy factors include heat, appliances and lighting. Few other developed countries require as much hot water per person as we do. Daily hot water usage in the UK is app. 11 gallons. The only country that uses more hot water, indeed more energy, per capita is the United Arab Emirates.

Energy is also still deceptively cheap in the USA. Most Europeans pay two to three times our cost for transportation and home convenience fuel. And we, resistant to new technologies like solar hot water, point-of-use hot water heaters, and heat-recovery of waste water, are using rather primitive equipment to heat up our precious showers.

But federal and state tax credits, depending upon where you live, can defray more than half the cost of new, more efficient equipment. The missing factor is our motivation to move forward technologically, embrace conservation until it becomes chic, and face up to the realpolitik of energy. It’s never been more cost-effective and patriotic to pursue alternative and renewable energy sources and equipment, but you do have to take the long view. The last solar hot water system I installed is calculated to pay the owners back in 10-12 years. Not many Americans are willing to wait that long to begin saving money on energy. Indeed, most of us don’t expect to be living in our present homes in ten years.

A feature of your home life that consumes 30% of your total energy budget deserves a second and then a third look. We’ll chew on this some more when next we meet. Until then, time your showers…….

It’s a Tankless Job


If I could give up the cruddy puns, I’d have more readers. As it is, the two of you are most welcome, and I salute your tolerant natures. The contraption shown at left is called a “tankless water heater.” This one is fired by propane, although we could show you electric or oil-fired models, and even a few that use wood. The idea is simple, but simple ideas are always hell for engineers. Water enters cold, leaves hot enough for American bath and kitchen use, and not much energy goes up the flue, if you believe the labels.

Compared to the electric tank that sits in my basement, the tankless heater is a marvel of efficiency. A crafty heat exchanger exposes the water to the gas flames/electric elements such that heat transfers at efficiency ratios up to 95%. My electric tank operates at closer to 85% due to various factors, mostly standby (idle) heat loss from the tank. 

The tankless heater sits cold, or barely warm, until you turn on the shower/faucet/dishwasher/laundry/jacuzzi. A flow switch alerts the unit that water is demanded, and the btus begin to flow immediately. A delay attends the operation of the heater, during which you run water, wasting a bit, and wait for the hot stuff. Usually fifteen to thirty seconds is enough. Then, as long as you continue to demand hot water continuously, the heater can produce as much as you can use, within limits.

Properly sized, the tankless heater will serve one point of use or several in your house. You calculate the capacity by the number of occupants and their habits. Teenagers count as a small village each. Old men like me are no big problem. Can I run the dishwasher while showering? Shall I operate the clothes washer and the dishwasher at the same time? There are easy formulas to help you get this right in one go.

The capacity for heating water in one pass is a thing that separates the tigers from the kittens. Electric tankless units are generally of smaller capacity, and two or more are installed in series to raise water to the desired temperature as it traverses the multiple heat exchangers. Propane or natural gas heaters are more aggressive, and usually one correctly sized heater will serve an average house. Only Republicans, to date, have been willing to accept the risks of the nuclear option, but they say the water is always hot. And wood burners can easily adjust the intensity of their heating plants by adding more logs/pellets/kindling to keep the heat exchanger cooking. The Waltons’ method, of course, was technically tankless, involving multiple pots hung over the fireplace and carried to the big washtub where a dirty Walton waited to be scalded clean.

We spent the last week at a “resort” (weathered 80 year old shacks perched on the dunes) on Cape Cod. The single modern convenience, besides a rather sluggish flush toilet (more on that topic only by request) is copious hot water supplied by propane-fired tankless heaters. Crank the shower control, wait a good half-minute, temper a bit with cold, and step in for the best shower you can get at any price. Yes, the shower’s  indoors; and it’s also outdoors— your choice. The blunt simplicity of the amenities is only meant to enhance your appreciation of the stunning views of sea, sand, birds, seals, whales (!), and well-fed tourists only capturable through wide-angle lenses. No, I won’t tell you where it is: they don’t advertise, and the waiting list stretches years in front of hopeful vacationers. Elitism has many faces.

At your house, the water heater can cost from $1 US to $3 US, depending upon the energy source and the equipment. If you’ve got a solar hot water system, you might be getting off VERY cheaply during these sunny warm days of summer. Pennies per day, just enough to run your pumps and sensors. Good for you. Next time we’ll revisit hot water and talk a bit about the more conventional optons.

What’s That Smell? Quick! To the Shower!

man-in-shower-blogOne of the seasonal energy features of summer is: more showers. Not so, say you? Take as many showers in cold weather as you do in summer? Well, let me tell you about my daughters. In their salad days as teenagers they took several a day between them. I, as a hard-w0rking contractor, often find myself in the rain-room more than once a day.

And the electric tank in the basement that supplies my hot water is working overtime to supply all that hot water for extra showers. So add to my energy bill for modest air conditioning comfort the expense of extra hot water for more laundry and showers. And the alternative? EEEEEEEeeeeewwww! What’s that smell? See the guy in the photo? Don’t get any closer, or you’ll receive way too much information about that person. Wait until he’s all done and dried off.

What’s Mr. Natural’s astute, energy-conscious remedy? Well. First things first. Short, tepid showers. You’re thinking, you don’t know my kids. No, I don’t know your kids. But I know how to turn down the settings on my water heater. And you can learn, too. Right here. And be extra careful if your tank is electric; use an insulated screwdriver and don’t remove the wireshield. Just follow the directions, do the upper as well as the lower thermostat, and you can become as unloved as a beginning tuba player in minutes. And keep your teenagers away from screwdrivers. Come to think of it, I’ll bet they don’t know or care where your water heater is located.

Stronger deodorant? Doesn’t instill confidence or convey that fresh clean feeling. but you can try. Hippie housefold hint no. 206: apply rubbing alcohol to your pits as you emerge from the shower, then use deodorant if you wish. Don’t try this, ladies, after you shave under there. Be warned.

And there’s what Kinky Friedman calls the “Waylon Jennings Bus Shower,” in which you splash and swab your armpits while standing at the sink. Saves water, job gets done. No fresh, clean feeling, though. Now wipe up the floor.

Between the laundry, hot water and the air conditioning, it’s hard to save an energy buck in hot weather. But you can try. Adjust your hot water heater, adjust your air conditioning thermostat, do full loads of laundry in cold water and hang the clothes in the sun to dry. Don’t waste energy pleading with your teenagers. Tell them they smell just fine.

Waste Not, Want Not? Sorry, Forget It

cooling-towers-blogIn the last post I implicitly accused you all of using too much water: you seemed to take it well. Now that you’re grumpy with me, I’m ready to take it all back. Yes, we Americans consume more water (the USGS calls it “withdrawal“) than most other countries, developed or developing (yes, China takes the biscuit, but they’ve got lots, for now). Yes, we squander lots of fresh water in our homes by flushing toilets, bathing, and washing our clothes. All true. But if the American people all stopped using water in their homes entirely tomorrow, water would still be an endangered resource for us.

  Who’s getting it all? Industry and agriculture, I’m afraid. Nor are those industries actively pursuing less water-intensive technologies, except where it suits them financially. About one sixth of all U.S. water usage is residential supply for personal use. One third of our “withdrawals” of fresh water goes toward agricultural irrigation. Good cause, actually, and it gets put on the crop and soaks into the ground, but it’s still lost water in many ways. Evaporation claims much of the water used for irrigation, and you can’t control where it comes back down. Certainly not Phoenix, where the water comes from far away in pipelines from reservoirs and evaporates to the air never to be seen again. At least not in Phoenix.

 Fully half of America’s total water usage is for industrial cooling, much of it consumed by evaporating devices called “cooling towers.”   Wherever heat needs to be removed from a process or material, evaporation, the most efficient means of heat transfer on the planet, is called into service. One pound of water, in evaporating, removes 970 BTU of heat from its surroundings. Nothing else compares, not even a cold Bud. And again, the evaporated water is lost to the immediate environment, since rain isn’t fair. Most industrial processes require the services of cooling towers, but the single most demanding industry is electric power generation, including nuclear power. Some plants use salt water, but not all.

   Don’t give up. We all need to become more aware of our consumption of fragile resources, and your water-saving strategies at home are important culturally and politically, as well as financially in your water bill. But, as in so many issues, the picture is much larger than our individual water habits, and we will have to participate in a much larger discussion to bring sanity to our national energy and resource policies. Meanwhile, be glad when your water bill shows that you’ve been conserving. It’s up to us regular folks to lead the charge, and in the greatest democracy in world history, government and industry must surely follow, hopefully in time to protect our fresh water supply from depletion.