Quiz: What You Don't Know About Home Heating


Photograph by Ilya Naymushin, Reuters

You know enough to come in out of the cold, but how much do you really know about the energy spent to keep people warm?

How much of the world's energy use is for generating heat?

  • 27 percent
  • 37 percent
  • 47 percent
  • 57 percent

Demand for heat dominates world energy consumption, far higher than transportation, which accounts for just 27 percent.

The hypocaust was a central heating system used in ancient Rome's public bathhouses. A continuously burning fire channeled heat into an open space beneath the bathhouse floor. What do today's engineers believe was the system's main drawback?

  • Carbon monoxide risk
  • Chance of floor collapse
  • Inadequate heat distribution
  • Connecting it to city aqueducts

Engineers believe deadly fumes easily would have escaped into the main room from the subfloor. However, the principles of the hypocaust are at work in today's water-circulating radiant floor heating systems.

Benjamin Franklin invented the mid-room cast iron furnace that became popular for heating homes throughout America and Europe in the late 1700s. What was the flaw with the original design?

  • It vented smoke from the bottom.
  • It required more wood than a wall fireplace.
  • The heat dissipated too quickly.
  • It created a home fire hazard.

The Franklin stove was an efficiency breakthrough that generated heat in all directions and provided warmth even when the fire went out, but fellow Philadelphian David Rittenhouse made the critical improvement of adding a chimney to the design to vent smoke.

Before the forced air systems that are typical today, steam heating was common in homes and apartments. Heat circulated from the basement on the simple principle that steam rises. But a banging sound often came from steam radiators. Why?

  • Rapid expansion of heated air
  • Clogged radiator air vents
  • A radiator that is tilted
  • Mineral build-up in the pipes

Among the many issues with this inefficient system is that floors get warped beneath radiators, causing them to tilt in a way that prevents proper water drainage. When the system heats up, steam passing through the trapped water causes banging.

What is the most prevalent method of home heating today in the United States?

  • Oil
  • Natural Gas
  • Steam
  • Electricity

Nearly 60 percent of homes in the United States are heated with natural gas, making it the most popular residential heating fuel.

Which of these appliances would a home in Japan be most likely to use for heat?

  • Geothermal heat pump
  • Kerosene space heater
  • Natural gas furnace
  • Hydronic radiant floor system

Room space heaters are far more typical in Japan than centralized systems, and kerosene is a popular fuel.

Russia's spending to heat homes is double that of fellow Arctic nation, Canada, in terms of energy “intensity” (heat consumed per unit of GDP). This is due to many factors, EXCEPT FOR:

  • Russia has colder average temperatures than Canada.
  • Soviet planners forced large numbers of homes to be located in the coldest regions of the country.
  • People in parts of Russia typically open their windows in winter to vent warm air.
  • At least one quarter of heat generated is lost in Russia's city heating distribution systems.

Canada has colder average temperatures, but its people live in the nation's warmer areas. Russia's energy waste is equal to all the energy consumed in France, but the nation recently has embarked on an efficiency drive.

Geothermal heat pumps, which channel the Earth's natural heat into the home, are among the most efficient heating technologies available. They are currently being installed in about 2 percent of new U.S. homes. What percentage of homes in Sweden have them?

  • 10 percent
  • 20 percent
  • 30 percent
  • 40 percent

Sweden's “technology procurement program” in the 1990s—aimed at developing reliable, efficient, and affordable heat pumps—jump-started the market, making this nation a world leader in this energy-efficient technology for the home.

What is the Annual Fuel Utilization Efficiency (AFUE) rating on the most efficient home furnace or boiler you can buy?

  • 80
  • 90
  • 95
  • 97

Some natural gas furnaces (and a handful of oil models) achieve super-high efficiency by condensing the water vapor produced in combustion, and using the heat from this condensation. In the more common 80 AFUE furnaces, 20 percent of the fuel goes up the chimney as exhaust.

In operating a central home heating system, what causes lost energy—and wasted money?

  • Dirty air filters
  • Leaky ductwork
  • A fan that operates longer than it needs to
  • All of the above

Although they need much less maintenance than old steam systems, oil-fired furnaces should be tuned and cleaned annually, gas-fired systems every two years, and heat pumps every two or three years to cut heating costs and ensure safe operation.





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