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- EXTRA EDITION
All homeowners want to save money on their energy bills, which is why they are often intrigued by gadgets, additives, and one-off products that claim to offer significant methods to cutting energy usage. These products are appealing because they usually cost significantly less than taking the whole-house approach to saving energy, which may involve adding insulation, sealing ductwork, and upgrading heating and cooling equipment.
But HVAC professionals warn that, in many cases, these products do nothing more than separate homeowners from their hard-earned money. As Jordan Goldman, LEED AP/CPHC, engineering principal, ZeroEnergy Design, Boston, noted, “The focus needs to be on upgrading the building envelope — that’s where the biggest benefits are going to be. There is no singular fix. Homeowners shouldn’t fall for magic bullets and anything that seems too good to be true.”
Barriers to Energy Savings
Some think radiant barriers can fall into the magic bullet category, and believe those who sell them often exaggerate how much money they can save the average homeowner. According to Oak Ridge National Laboratory, for homes with uninsulated air conditioning ductwork in the attic in the Deep South (such as Miami and Austin, Texas), radiant barriers could potentially reduce utility bills by as much as $150 per year. However, if there are no ducts or air handlers in the attic, the savings range from about $20 per year in Miami to $5 per year in Baltimore.
As can be seen in Table 1, the most significant energy savings are realized when a radiant barrier is combined with more extensive retrofits such as improving the ductwork and adding insulation. And, in colder climates, their benefits are negligible to nonexistent, said Hal Smith, co-owner, Halco Energy, Phelps, New York. “Selling radiant barriers in my area is an absolute scam because, in my climate, they do no good. Companies have come through here claiming their radiant barriers — which are nothing more than glorified aluminum foil — will hold heat in the house, but that’s not true. There are radiant barrier products that do work somewhat, but they have to be installed properly and in the right climate.”
Unfortunately, radiant barriers are often not installed properly, and homeowners do not experience the promised energy savings. “A radiant barrier can be effective, but most of the ones we see are not properly installed, and the reason we are called out to the home is because it had little or no impact on comfort or energy use,” said Jerry Unruh, owner, ABC Cooling and Heating, Fresno, California.
Regardless, homeowners remain susceptible to advertising claims that radiant barriers are a good way to cheaply add R-value to a home’s walls and roofs, said Goldman. “But, the painful truth is you need thickness in order to add R-value. There’s no magic material that is going to add R-20 in a ½-inch layer. If the HVAC equipment is in an uninsulated attic, the best thing to do is to enclose the ductwork and all the equipment within the conditioned envelope, and that’s going to have a much bigger benefit than any single product like a radiant barrier.”
Brian Butler, project manager, Savilonis Construction, Natick, Massachusetts, agrees, noting that while radiant barriers have a “thin veneer of legitimacy,” a better approach is to design homes with the ducts inside the thermal boundary in the first place. “While duct leakage in this scenario could result in poor distribution and subsequent occupant discomfort, which could lead to higher thermostat settings to satisfy the demand, the total energy demands would still be a whole world away from the losses experienced with ducts installed in uninsulated attics.”
Another supposedly energy-saving product that Smith takes issue with is the power factor correction device. These devices are advertised as being able to reduce the amount of current drawn from power lines while simultaneously providing the necessary amount of current to appliances inside the house. But, according to the National Institute of Standards and Technology (NIST), they don’t work.
“When the companies rolled into town offering these devices, we decided to test them in-house,” said Smith. “We set up motors in our shop and had them run for days on end, metering them with and without the device. At the end of the day, the device didn’t make any difference in the power consumed. It can be very confusing, because they can be made to look like they work. But what we found after we tested it is that the device really didn’t reduce the utility bill.”
Attic fans are also advertised as energy-saving devices, but in some cases, they can actually drive up energy costs rather than reduce them. Attic fans are intended to cool hot attics by drawing in cooler outside air from attic vents (soffit and gable) and pushing hot air to the outside. But, according to Energy Star, if an attic has blocked soffit vents and is not well-sealed from the rest of the house, these fans will suck cool conditioned air up and out of the house and into the attic. This will use more energy and make the air conditioner work harder, which will increase utility bills in the summer.
The bottom line, said Goldman, is that if something seems too good to be true, it usually is. “In all segments of the efficiency market, there are a whole lot of products being marketed to do things they flat out don’t do. Manufacturers and marketers are seeing an opportunity to capitalize on the wave of enthusiasm for energy efficiency and green design and sell products to an otherwise uninformed target audience.”
The only way to make customers aware of the dubious nature of these products is for contractors to start educating customers about retrofits that can truly make a difference on their energy bills. “People want to believe the cheap fix is going to do great things, but it never works out that way,” said Smith. “Before we make any improvements, we do an energy audit, which includes blower door testing, combustion appliance testing, and using a thermal imaging camera to detect leaks. Depending on the results of the energy audit, we can offer a range of solutions to fix the problems. But we don’t know what those are until we test.”
If customers still believe these products work as advertised, Unruh suggests they look to the state of California, which does not recognize most of the aforementioned products as significant energy-saving upgrades. “In fact, they aren’t even available in our software to model them,” said Unruh. “The only way to guarantee energy savings is to do an energy audit, so we are able to see exactly where the home is using and losing the most energy. Then we can offer whole-house solutions that actually improve the home’s comfort as well as save energy. In other words, there is no guess work.”
Homeowners who cannot be convinced to invest in an energy audit should still be educated about real ways they can save energy so they don’t fall prey to advertising claims. “If customers have a couple of hundred bucks to spend, they should be encouraged to change out their incandescent light bulbs and buy a programmable thermostat,” said Goldman. “And changing their behavior is free — they can shut off the lights, turn off the cable box when it’s not in use, and only run their washing machines or dishwashers when they have a full load. These are very commonsense things that aren’t common sense for a lot of people.”
Still, some homeowners will continue to believe that buying a singular product will result in significant energy savings. “There is not just one cool gadget that is ever going to be a game changer — houses are too complicated for that,” said Butler. “Dialing down a home’s energy consumption in a meaningful way requires planning, measuring, verifying, and attention to details. Unfortunately, scams are easier to advertise than blower door tests, so don’t expect such ‘remedies’ to disappear any time soon.”
Publication date: 8/18/2014