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Shelter: Heating and Cooling

Harnessing Energy

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The human body likes to stay at a uniform temperature—typically, a little more than 98 degrees, according to Harvard Medical School—and deviating too much from that can cause trouble. If an environment gets so cold that a person’s body temperature drops below 95 degrees, hypothermia can cause slowed breathing, gradual loss of motor skills, and eventually death. In an extremely hot environment, where the body rises about 104 degrees, the result can be heat stroke, which can be fatal as well.

But even if you don’t encounter extreme conditions, run-of-the-mill cold weather can threaten weaker, more vulnerable members of your community, such as infants and the elderly, as this Centers for Disease Control and Prevention web page explains. Ditto for heat waves; here’s a Scientific American article on the effects of excessive heat on human health.)

So no matter how hardy you think you are, you’re going to need a way to keep your shelter warm in the winter and cool in the summer. Additionally, unless you relish ice-cold showers in January, you’re going to probably want to have a way to heat your water supply as well. But don’t worry, because there are multiple heating and cooling options at your disposal.

  • Design Your Shelter for Thermal and Energy Efficiency. Adequate insulation, for example, can help protect you against both heat and cold, and cut down on your energy needs as well. From the New Zealand website Wanakahomestead, here’s a primer on designing a sustainable home with optimal thermal efficiency.
  • Install a Wood Stove. If a source of firewood is nearby, Hunt favors using a wood stove. “Wood really is the best renewable resource out there for heating your home and your water,” He explains. “That’s what the Amish do.” Check out Woodheat.org, the website of the nonprofit Wood Heat Organization, for useful how-to guidance on how to pick a stove and use it for heat.
  • Utilize the Sun.  You’ve probably been thinking of solar energy as a way to generate electricity, butwith the right design, you also can collect solar heat and store it, and then utilize it to heat your home in cold weather. But you need to do know about how to properly orient windows and set up a distribution mechanism. Here’s a U.S. Department of Energy website that explains how passive solar heating works. And one good option for heating water is to have a passive solar water heater. Hunt offers a caveat: It’s still necessary to pump the water, which requires additional energy. For a more detailed explanation of the technology, consult the how-to manual Solar Water Heating, by Bob Ramlow and Benjamin Nusz.
  • Biodiesel for Heat. Utilizing vegetable oil to heat your home may seem like a far-out idea, but according to this Mother Earth News article on the subject, you can run an old-fashioned oil-fired boiler on biodiesel fuel mixed with with some tinkering. Here also is a Wired article on the promise of biodiesel for home heating. The best part is that you can actually grow the raw material to make the fuel yourself. An acre of sunflowers, for example, yields about 102 gallons of biodiesel fuel.
  • Resort to Old-Fashioned Technology to Keep Cool. It may come as a shock to those of us alive in the 21st Century, but there was a time when people lived in extremely hot places such as Arizona and Nevada without central air conditioning, or even those ineffectual little window units. From Fiscalgeek.com, here’s a detailed, picture-laden how-to guide on how to build a “swamp cooler,” which uses evaporation to cool a room.
  • Propane is an Option. An on-demand propane-fueled water heater, which only burns fuel when a prepper actually needs it for showers, cooking or washing, is another option, according to Hunt.

If You Only Do Three Things:

  • Make sure your shelter has a lot of insulation.  That will help keep you warm in the winter and cool in the summer.
  • Get a wood stove.  Burning wood  is a tried-and-true method of staying warm.
  • Think about installing a solar water heater. Hunt notes that the ability to take a warm shower can be a morale-maintainer, even in trying circumstances.


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1 comments
Thomas Anderson
Thomas Anderson

Very good overview.  I would recommend that anyone designing an efficient shelter become familiar with the different types of heat transfer -- conduction, convection, and radiation.  All three of these must be controlled.  High-density closed-cell spray foam is excellent for all three, especially when combined with a foil radiant barrier.