Home Energy TechTips

For the most part, the behavior that defines how we consume energy is based on habits and routine.  Except for a monthly correspondence with our local utility, we remain largely out of touch with the cost of our behaviors.  How would our usage habits change if we were faced with more frequent information regarding our energy consumption?  Do we even care?  Would the conspicuous placement of the display on a residential energy management system motivate us to change?

Several months ago, Newport posted a Featured Technology update on Residential Energy Management Systems.  In the update, we included a quote from a senior-level executive at an electrical systems contractor who, when asked about the effect of these types of products on consumption habits, said, “If you can see [your energy use] on a display, people take a real interest in lowering demand.” 

So, think about the rapidly changing digits on a gas pump as you fill up your car at the station on the corner.  As the cost appears to rise at a seemingly exponential rate relative to the gallons you’ve pumped, you’re face-to-face with timely feedback on your usage habits. 

Remember pumping gallon after gallon of gas into your car at $4.25 per?  Can you recall the feelings of disgust as you realized how much it cost you to ‘fill-up’? 

Consider this:

Would the magnitude of those feelings been the same if you were allowed to drive for a month without incurring any cost, only to be billed for your use of gasoline shortly after a one-month billing cycle had passed? 

For some people, maybe so.  But for the rest of us, definitely not. 

To better evaluate the potential for more timely (and more frequent) feedback to change household consumption of energy, Newport went out and found what the academic world had to offer.  We’ve highlighted only the most important points in this edition of the Home Energy Tech Tips Blog.

To start, the studies recognize feedback as what is known as a consequence intervention.  You use the energy and then you’re provided with information based on your use.  This as opposed to antecedent interventions which would include a homeowner participating in a goal setting exercise or obtaining a home energy audit. 

One study found that as compared to a variety of antecedent and consequence interventions, feedback was the most successful at motivating households to reduce energy use.  Most important was the fact that the more frequent the feedback became the more effective it was observed to be.  How effective?  A separate study found that feedback strategies can reduce consumption by as much as 15%.

With the continuous or at least more frequent feedback strategy having widespread success at providing the impetus for households to change their consumption habits, it’s worth noting how the feedback should be presented.  One researcher suggested providing homeowners with the average usage for a similar size household in a similar size home.  The purpose of this is that people have a tendency toward social norms.  If seeing the usage of other households convinces them that the norm is conservation, then this could lead them to change their own consumption habits.  Meanwhile, other studies provided support for information that is stated in terms of cost, instead of more technical jargon like BTU’s or kWh’s. 

What is particularly important about using dollars as a metric to measure usage was a finding that noted the combination of goal-setting and frequent feedback as being an especially effective approach.  It would seem rather obvious that most households would set their goals in dollar terms, not kilowatt hours. 

The research on the value of more frequent feedback as a means to encourage households to reduce their energy consumption is compelling.  Check back soon for Part II of Newport’s series on Household Energy Use.  In this next edition, we’ll discuss reduced energy usage in terms of using energy less vs. using it more efficiency.

Newport recently attended the Alliance to Save Energy’s 2010 Great Energy Efficiency Day - which showcased panels including Members of Congress, federal, state, and local government officials, and many of the nation’s top energy efficiency advocates.  Panel topics focused on energy efficiency related stimulus funds, transportation energy and transit oriented development, and technology solutions in energy efficient buildings. 

During a panel on energy efficiency technologies, Steven Hilton of Meritage Homes, the Chairman of the Energy Committee for the Leading Builders of America discussed the group’s top three priorities which included the adoption and implementation of a nationally-recognized, home energy rating standard and label “such as the U.S. Department of Energy (DOE) EnergySmart Home Scale.”  The EnergySmart Home Scale or E-Scale is currently used by DOE’s Builders Challenge program - a voluntary home energy labeling initiative that helps builders market energy efficiency in their homes. 

More information can be found at www.buildingamerica.gov/challenge.  The support of the nation’s largest builders shows the quickly rising popularity of the E-Scale as national leaders debate the possibility of home energy labeling on a broader scale.  The EnergySmart Home Scale relies on the on a nationally recognized  industry standard - developed by RESNET - for home energy ratings that follows strict rules related to third-party verification, which is vital to the credibility of any rating label.

Miscellaneous electrical loads (MEL’s) correspond to the use of devices that do not result in the heating, cooling, water heating, or lighting of the home.  The consumption of energy by MEL’s can be difficult to reduce because of the diversity of their use.  In fact, each MEL will only consume a small amount of energy, but the problem is that their use has proliferated as the popularity of home electric products has become more widespread. 

MEL’s typically include energy consumption by a home’s television, computer, microwave, alarm system, or pool pump / heater.  The energy used by garage-door openers, coffee makers, door bells, vacuum cleaners, and clock radios (among many others) can also be categorized as an MEL. 

The following includes tips for how to reduce the energy usage from MEL’s:

• Plug devices into a power strip. This will make it easier to disconnect or turn-off the products when they are not in use. Many home electronic products still draw substantial amounts of energy even in their ’stand-by’ or ‘ready’ modes.
• Take an inventory of your home electric devices. Are there ones that are always plugged in but hardly ever in use? Consider doing away with such products.
• When looking for new household products, pay special attention to those that have earned the Energy Star. These products have met strict guidelines set forth by the EPA and the U.S. DOE for energy efficiency.
• Install an energy feedback device which will report your home’s real-time energy usage. This will allow the home’s energy usage to become more transparent. In turn, you can become more active in managing and reducing your home’s energy usage from MEL’s.

The importance of reducing MEL’s in the home is underscored by the fact that energy consumption by these products adds to the cooling load of the home.  In other words, these devices give off heat that is then retained within the building envelope and, in a warm-temperature climate, represents an additional burden to the home’s cooling system.

Click here to check out Newport’s recent piece on Advanced Telemetry’s Residential Energy Management System in its Featured Technology section.  As noted above, the value proposition associated with these products is that the homeowner is more likely to curtail their energy wasting habits if the cost of these habits is made available to them in real time.

An unvented attic assembly effectively incorporates the home’s attic into the building envelope.  This type of attic assembly serves as an alternative to vented attic assemblies that leave the attic space outside the building envelope and are forced to vent the absorbed heat back outside the structure.

Take a look below to see a list of the Pro’s and Con’s of an Unvented Attic Assembly. 

PROS: 

• Prevention of Mold and Mildew:

By containing the HVAC system and related duct work within the building envelope, there is a reduction in the potential for condensation. Temperatures in vented attic space can become quite high and in certain climates the air can be rather humid as well. As a result, any cool surface in the attic will develop condensation. The moisture from condensation brings with it the potential for mold and mildew.

• Greater Energy Efficiency:

As stated above, when the HVAC system and related duct work are located outside the building envelope, they may be exposed to high temperatures and humid air. This serves to decrease the efficiency of the HVAC system. The effect is that additional energy usage is required for the system to function at a particular level.

• Longer Useful Life of the HVAC System:

The useful life of the system will be increased by allowing the HVAC system to operate in a location that has a lower air temperature and humidity level than if it was placed outside the building envelope.

• No Roof Leaks Due to Ice Blockage:

In colder climates, if the attic ventilation system is not working properly, the snowpack on the roof will melt and reform as ice. This ice can cause blockages which may result in roof leaks. Unvented attic assemblies that use an air impermeable insulation will significantly increase the roof’s ability to maintain a temperature below freezing on its surface.

CONS:

• Problems with Asphalt-Shingle Roofs:

On a roof with asphalt shingles and an unvented attic assembly, the temperature of the shingle will be higher than if the shingles rested upon a vented attic. The effect of the increased temperature is that the life of the asphalt shingles can be reduced by about fifteen-percent. This would result in a several year reduction in the service life of a home’s asphalt shingled roof. The warmer the climate, the larger the reduction of the service life of the asphalt-shingle.

• No Way to Vent Moisture, Should it Occur:

Given the fact that an unvented attic assembly does not contain any ventilation, there would be no way for the space to vent away condensation or other moisture should it somehow become present in the attic space.

An insulated spray foam product is commonly used to create the most effective air tight building envelop.  Click here to check out Newport’s Featured Technology piece on the LD-R-50 from Icynene and see what the next generation of high performance insulation is all about.

Newport’s Phil Sapone recently attended the 2009 Greenbuild International Conference at the Phoenix Convention Center in Phoenix, Arizona.  This year’s event featured over 1,800 exhibit booths displaying the latest and most innovative green building products. 

ThermaCote being applied to a residential building

A product of particular interest from the event is called ThermaCote.  ThermaCote is a fluid applied ceramic insulating coating which serves as a highly effective radiant heat barrier.  When applied, the coating provides an insulation value equivalent to that of common insulation types, but with a much thinner coating.  Furthermore, ThermaCote is water resistant, has sound deadening capabilities, and boasts a zero flame spread. 

Highlights of ThermaCote’s properties include its ability to act as a vapor barrier, water sealant, air sealant, thermal barrier, or thermal blocker.

 ThermaCote is also able to eliminate or reduce:

ThermaCote can be used to seal the envelop of any residential structure to minimize the amount of conditioned air loss.  It can be applied to either the interior or exterior walls to eliminate thermal bridging.  It can also be used to coat exposed piping to keep the heat in or to eliminate condensation.  Another application involves spraying the ThermaCote on the underside of a residential attic to dramatically reduce the attic temperature in warm weather months while helping to minimize heat loss during the winter months.  ThermaCote is capable of adhering itself to wood, metal, fiberglass, rubber, asphalt shingle, plastic, or masonry finishes.

Newport’s Matt Evans and Phil Sapone recently attended the 2009 Remodeling Show at the Indiana Convention Center in Indianapolis.  The event attracted thousands of remodelers, replacement contractors, general contractors, custom builders, and other home improvement professionals to Indianapolis to interact with product manufacturers in almost every major product category. 

Right now, there is significant opportunity in the marketplace for remodelers.  As homes become older, and energy costs continue to rise, products that offer homeowners the ability to address their aging homes in an energy efficient manner will be in high demand. 

Examples of some products from the show that are relevant to this point include the following:

Alligator HYBRID SIP Room Additions are high performance building panels used in walls, floors, and roofs for residential building and remodeling.  While typical SIP panels are made by sandwiching a core of rigid foam plastic insulation between two structural skins of oriented strand board (OSB), the Alligator HYBRID SIP Room Additions are manufactured with a special closed cell EPS foam sandwiched between Alligator Board panels rather than OSB.  The Alligator Board is made from a special material comprised mainly of magnesium.  The HYBRID panels provide high levels of insulation and are extremely airtight.  This translates to a reduction in the amount of energy required to heat and cool a home. 

Green Fiber Blow-in Natural Fiber Insulation is a natural product made from 85% recycled paper fiber.  The insulation can be used over existing cellulose, fiber glass, or mineral wool insulation.  This natural fiber insulation fills all gaps and voids which reduces infiltration and convection - each primary causes of heat loss in a home.  Green Fiber insulation is also two to three times denser than comparable fiber glass batts, which helps keep the home warmer in the winter and cooler in the summer. 

Reflectix, Inc. is the world’s largest manufacturer of reflective insulation.  Reflectix’s insulation is a reflective insulation consisting of two outer layers of 96% reflective material, bonded to two layers of heavy gauge polyethylene bubbles.  Within a home, Reflectix products can be laid in an attic, crawl space, masonry wall, beneath radiant floor wood joists, and on a regular wall.  The resulting impact on a home’s energy efficiency can be substantial.

Newport staff led a tour of DOE Builders Challenge-certified homes at the recent EEBA conference in Denver.  Featured homes were “Solar Harvest,” built by Eric Doub of Ecofutures, his personal residence in Boulder with an impressive negative 3 HERS rating and a duplex by Sean Smith and Company in Denver’s Washington Park neighborhood with a 37 HERS score.  Following the tour, the two builders joined Tom Wade of Artistic Homes for a classroom discussion at the conference on marketing Builders Challenge homes.

The picture above shows Eric Doub of Ecofutures Building Inc. standing next to his panel box showcasing the negative 3 HERS score shown on the Builders Challenge label.

The picture to the left shows Ed Pollock from DOE’s Building Technologies Program congratulating Sean Smith of Sean Smith & Co. LLC.

Also at EEBA, Newport staff facilitated a discussion of the status of DOE’s Building America program and led a workshop on a recent high performance home project for the New York State Energy Development Authority.

Proper outdoor maintenance of a heat pump includes monitoring the angle at which the unit rests.  The heat pump unit should be relatively level without more than ten-degrees of tilt.  It is important to keep the unit level so that all of its parts are able to remain properly lubricated.  If the heat pump is out of level, oil may become trapped in certain areas of the motor which means that other areas of the motor will be deprived of the lubricant.  Parts that are under lubricated will work less efficiently and the unit will need to use more energy to operate effectively. 

In addition, if the unit is not level, liquid could make its way into the compressor.  The compressor is designed to compress air, not fluid.  Over time, this reduces the efficiency of the unit, requiring it to use more energy to function at the desired level.  Finally, heat pump units that are not level could place stress on refrigerant lines running between the home and the unit.  Lines under this type of stress are susceptible to breaking. 

In order to ensure that the heat pump is level, the following steps can be adhered to: 

• Prior to each heating season, set a carpenters’ level across the top of the heat pump. Measure for any tilt by the heat pump from left to right and then turn the level ninety-degrees to determine if the heat pump is exhibiting any tilt from front to back.
• If the heat pump is titled at some angle according to the level, it is easier to adjust the level of the pad on which the heat pump rests, instead of the level of the heat pump itself.
• Begin by lifting the side(s) that is below level with a pry bar or other useful tool. You can then build up the ground beneath it with small stones or variation of crushed rock.

Having some sort of small stones or crushed rock at the base of the unit is preferable to placing the structure on a dirt / grass base.  This is because the stones or crushed rock allow for proper drainage around the heat pump and correspondingly prevents the unit from tilting or sinking.

In addition to making sure the heat pump is level, check to see that the unit is stable and does not wobble.

The picture here shows a heat pump from a high performance home built by Belmonte Builders.  The energy saving features of this home were selected by Newport Ventures and allowed the home to obtain a HERS Index of 91.4.  To learn more about this home please read the following case study.