Forgot Password?
Home arrow GreeniacsGuides arrow Energy arrow High Efficiency Heating
Written by Elizabeth Jones   
Share |
Tuesday, 30 October 2012

High Efficiency Heating

Cold days are upon us as autumn sets in. Are you wondering whether you can weather another winter of high heating costs? Is it time for a new furnace? In most homes, heating is the largest energy expenseóit accounts for 35-50% of annual energy bills in the colder parts of the United States.1 Even if your furnace isnít that old, upgrading to a higher efficiency system might really pay off. The following guide will help you to determine whether high efficiency heating is a good option for your home or business.

BENEFITS FOR THE ENVIRONMENT: Switching to a high efficiency heating system can save a great deal of energy. The less energy we use to heat our homes, the less carbon emissions and greenhouse gases are released into the atmosphere, and the less we contribute to global climate change .

BENEFITS FOR YOUR WALLET: High efficiency heaters can pay for themselves in just a few years and can start generating return for many more years after that. If you can afford to put in some money now, you will start getting lower utility bills immediately!

TIME AND EFFORT: Medium. Doing your due diligence to find the best high efficiency heater for your home can seem overwhelming. However, there are a number of online resources you can use to assess your options. Plus, most contractors are now very familiar with these newer products.

Step 1: Determine the general efficiency of your current furnace
The best furnaces on the market today have efficiencies upwards of 97 percent. In contrast, most standard furnaces installed in the last 20 years have an efficiency that is less than 85%.2 This means that even though your current furnace may have an expected lifetime of 25 years, it could still pay off to replace it before it fails. Certainly if your furnace or boiler is more than 20 years old, itís time to call a contractor. According to the American Council for an Energy-Efficient Economy, you should also consider a replacement if your system is:
  • An old coal burner that was at one point switched over to oil or gas.
  • An old gas furnace without an electronic ignition. If your furnace has a pilot light, it was probably installed prior to 1992 and has an efficiency of about 65% (yikes!).
  • An old gas furnace without vent dampers or an induced draft fan. Dampers and fans limit the amount of heated air that is wasted through release up the chimney when the heating system is off.3
Old vs. new heating system
Old vs. new heating system.4

Step 2: Conduct a detailed study of the efficiency of your current furnace
If you are still on the fence about whether you should look into a new furnace, the easiest thing to do is to hire a home performance or heating contractor5 who can perform a detailed audit of your existing system. In some cases it may be most cost effective to spend your money to improve wall and window insulation, repair ductwork, or tune up your system.6 You may also be able to upgrade your furnace by cleaning it, resealing your ductwork, or replacing your pilot light with an electronic ignition. More maintenance tips are available at the U.S. Department of Energy website. You can also read this guide to insulating your home which will help you save on your energy costs year-round. Another thing to consider when thinking about investing in a new furnace is whether there are ways to reduce the amount of time you will need to use your furnace. Turn down that thermostat and snuggle up in a warm sweater with your sweetie!

This is a 1940s poster encouraging tenants to use their heater less to help aid the war effort
This is a 1940s poster encouraging tenants to use their heater less to help aid the war effort.7


Step 3: Calculate Your Return on Investment
The easiest back-of-the-envelope calculation you can make to see if a new heating system will pay off is a payback period calculation. Obtain last yearís fuel bills from your gas utility company. Multiply last yearís bills by 20 percent, then divide that total into $3,000 Ė the average cost of buying and installing a new system.8 The total you come up with is an estimate of the number of years it will take you to get back your investment and start saving outright. Also keep in mind that if natural gas prices go up, this will shorten the payback time.

To determine the return on investment, figure out approximately how much it will cost to install a new system. Use the table below to calculate the amount of money you can save every year with a more efficient system.
  • First, find the horizontal row corresponding to your current, old systemís AFUE. AFUE is the annual fuel utilization efficiency, the thermal efficiency measure of combustion equipment like furnaces, boilers, and water heaters.
  • Next, choose the vertical column corresponding to the proposed, new systemís AFUE.
  • The number at the convergence of the chosen row and column is the projected dollar savings per hundred dollars of existing fuel bills.


Existing System AFUE

New/Upgraded System AFUE

55%

60%

65%

70%

75%

80%

85%

90%

95%

50%

$9.09

$16.76

$23.07

$28.57

$33.33

$37.50

$41.24

$44.24

$47.36

55%

----

$8.33

$15.38

$21.42

$26.66

$31.20

$35.29

$38.88

$42.10

60%

----

----

$7.69

$14.28

$20.00

$25.00

$29.41

$33.33

$37.80

65%

----

----

----

$7.14

$13.33

$18.75

$23.52

$27.77

$31.57

70%

----

----

----

----

$6.66

$12.50

$17.64

$22.22

$26.32

75%

----

----

----

----

----

$6.50

$11.76

$16.66

$21.10

80%

----

----

----

----

----

----

$5.88

$11.11

$15.80

85%

----

----

----

----

----

----

----

$5.55

$10.50

90%

----

----

----

----

----

----

----

----

$5.30



Annual Estimated Savings for Every $100 of Fuel Costs by
Increasing Your Heating Equipment Efficiency Assuming the Same Heat Output9

For example, letís assume that the AFUE of your present heating system is 65%, and you plan to install a new high efficiency system with an AFUE of 90%. Your projected savings is $27 per $100 of fuel costs. This means that if your annual fuel bill is $1,300, then your yearly savings will be approximately $27 x 13, or $351. Your return on investment will be the quotient of your first year savings divided by the installed cost. In the example above, the ROI = $351 ų $2,500 = 0.14 = 14%.

Step 4: Pick a Furnace
Furnace retrofits are fuel-specific. This means that if you do plan to replace your furnace, you should check out the following, fuel-specific retrofit information guides: When choosing a furnace, remember that the more efficient your new furnace, the more money you will save in the long run. ENERGY STAR furnaces are a good bet. ENERGY STAR certified furnaces sold in the southern portion of the U.S. are up to 12% more efficient than standard models; ENERGY STAR certified gas furnaces sold in the northern half of the U.S. are up to 16% more energy efficient than baseline models; while oil furnaces are up to 4% more energy efficient than baseline models.10 The bottom line is that if a new energy efficient furnace will pay for itself in 5 to 10 years and you can afford the upfront cost, both you and the environment will benefit in the long run!11
Browse all Greeniacs Guides Browse all Greeniacs Guides        Browse all Greeniacs Articles
_______________________________________________________________________________

1http://aceee.org/consumer/heating
2http://www.energystar.gov/index.cfm?fuseaction=find_a_product.showProductGroup&pgw_code=FU
3http://aceee.org/consumer/heating
4http://energy.gov/energysaver/articles/furnaces-and-boilers
5http://aceee.org/consumer/how-choose-contractor
6http://aceee.org/consumer/heating
7http://www.treehugger.com/slideshows/energy-policy/12-great-posters-when-turning-down-thermostat-and-preparing-winter-was-patriotic-act/
8http://bennettsheetmetal.socialtract.com/2011/09/01/is-it-time-to-replace-your-furnace-do-the-math/
9http://energy.gov/energysaver/articles/furnaces-and-boilers
10http://www.energystar.gov/index.cfm?fuseaction=find_a_product.showProductGroup&pgw_code=FU
11http://www.treehugger.com/renewable-energy/the-value-of-a-high-efficiency-home-furnace.html




Add your comment
RSS comments

Only registered users can write comments.
Please login or register.

Click here to Register.  Click here to login.

Last Updated ( Tuesday, 30 October 2012 )

SEARCH GREENIACS.COM

Green Facts

  • A steel mill using recycled scrap reduces related water pollution, air pollution, and mining wastes by about 70%.

  • Recycling 1 million laptop computers can save the amount of energy used by 3,657 homes in the U.S. over the course of a year.

  • A laptop consumes five times less electricity than a desktop computer.

  • Current sea ice levels are at least 47% lower than they were in 1979.

  • 77% of people who commute to work by car drive alone.

  • A tree that provides a home with shade from the sun can reduce the energy required to run the air conditioner and save an additional 200 to 2,000 pounds of carbon over its lifetime.

  • States with bottle deposit laws have 35-40% less litter by volume.

  • Turning off the tap when brushing your teeth can save as much as 10 gallons a day per person.

  • Glass can be recycled over and over again without ever wearing down.

  • Plastic bags and other plastic garbage thrown into the ocean kill as many as 1,000,000 sea creatures every year.

  • Recycling for one year at Stanford University saved the equivalent of 33,913 trees and the need for 636 tons of iron ore, coal, and limestone.

  • American workers spend an average of 47 hours per year commuting through rush hour traffic. This adds up to 23 billion gallons of gas wasted in traffic each year.

  • An aluminum can that is thrown away instead of recycled will still be a can 500 years from now!

  • A single quart of motor oil, if disposed of improperly, can contaminate up to 2,000,000 gallons of fresh water.

  • Washing your clothes in cold or warm instead of hot water saves 500 pounds of carbon dioxide a year, and drying your clothes on a clothesline six months out of the year would save another 700 pounds.

  • Americans use 100 million tin and steel cans every day.

  • One recycled aluminum can will save enough energy to run a 100-watt bulb for 20 hours, a computer for 3 hours, or a TV for 2 hours.

  • You will save 100 pounds of carbon for each incandescent bulb that you replace with a compact fluorescent bulb (CFL), over the life of the bulb.

  • Americans throw away more than 120 million cell phones each year, which contribute 60,000 tons of waste to landfills annually.

  • Due to tiger poaching, habitat destruction, and other human-tiger conflicts, tigers now number around 3,200óa decrease in population by about 70% from 100 years ago.

  • The World Health Organization estimates that 2 million people die prematurely worldwide every year due to air pollution.

  • Refrigerators built in 1975 used 4 times more energy than current models.

  • Shaving 10 miles off of your weekly driving pattern can eliminate about 500 pounds of carbon dioxide emissions a year.

  • You will save 300 pounds of carbon dioxide for every 10,000 miles you drive if you always keep your carís tires fully inflated.

  • Nudge your thermostat up two degrees in the summer and down two degrees in the winter to prevent 2,000 pounds of carbon dioxide from entering the atmosphere.

  • In California homes, about 10% of energy usage is related to TVs, DVRs, cable and satellite boxes, and DVD players.

  • Less than 1% of electricity in the United States is generated from solar power.

  • 82 percent of greenhouse gas emissions in the U.S. come from burning fossil fuels.

  • Youíll save two pounds of carbon for every 20 glass bottles that you recycle.

  • For every 38,000 bills consumers pay online instead of by mail, 5,058 pounds of greenhouse gases are avoided and two tons of trees are preserved.

  • Bamboo absorbs 35% more carbon dioxide than equivalent stands of trees.

  • Recycling aluminum saves 95% of the energy used to make the material from scratch.

  • If every U.S. household turned the thermostat down by 10 degrees for seven hours each night during the cold months, and seven hours each weekday, it would prevent nearly gas emissions.

  • Recycling 100 million cell phones can save enough energy to power 18,500 homes in the U.S. for a year.

  • Every week about 20 species of plants and animals become extinct.

  • Rainforests are being cut down at the rate of 100 acres per minute.

  • In the United States, automobiles produce over 20 percent of total carbon emissions. Walk or bike and you'll save one pound of carbon for every mile you travel.

  • Americans throw away enough aluminum to rebuild our entire commercial fleet of airplanes every 3 months

  • It takes 6,000,000 trees to make 1 year's worth of tissues for the world.