Energy Advisor Blog

Fact or Fable: R-22 Insulation Saves Twice That of R-11?

Tech Resources, Inc. - April 2011

Key Points:

• Adding insulation can reduce energy costs.
• Doubling R-value does not double the energy savings.
• Caulking and sealing joints to reduce air leakage are excellent ways to reduce energy costs.

All insulation is rated according to its resistance to heat flow (thermal resistance), measured in units of R-value in the United States. The inverse of thermal resistance is conductance, referred to as the U-value (U = 1/R), which in the United States is measured in units of BTU/square foot-Fahrenheit hour. Whereas R-value is intuitively easier to understand (the higher the R-value, the better the insulating properties), U-value is more useful in calculations because it describes the actual amount of heat that will move through the material for each degree Fahrenheit difference in temperature from one side of the material to the other. R-values of different components can be added (all the different layers of a wall, for example). U-values cannot be directly added.

Total R-value = 7 + 7 + 7 = 21

Total U-value = 1/(7 + 7 + 7) = 1/21 = 0.048

If you were to improve the roof insulation from R-7 to R-21, for example, you could cut the energy losses through the ceiling by 65% with the higher R-21 value (1/21 versus 1/7 U-value or 0.05 versus 0.14).  Therefore, the overall energy bill for the heating season would be reduced by about 23 percent (65 percent of 35 percent), and can be estimated based on the square footage of the newly insulated building. This is because roughly 45 percent of a typical building’s energy loss is through the walls; 35 percent is lost through the roof; and the balance is lost through windows, doors, cracks and so forth. The myth persists that if R-11 insulation in your house saves heat and money then R-22 insulation saves twice as much and R-44 walls double your savings again. The energy (and money) you save by adding more insulation diminishes quickly. Starting with an R-value of zero, every doubling of units in R-value cuts the amount of heat loss through the wall or ceiling by about half, as shown in Figure 1. The amount of heat escaping through the walls or ceiling soon becomes so tiny that adding more insulation is almost pointless.

Permission to use this article has been granted by Tech Resources, Inc.
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Smart Grid - Helping You Take Control of Your Energy Use

Meghan McGuire Denlinger- February 2011

Perhaps you saw a scarecrow dancing in a substation during a Super Bowl commercial, read a magazine, or spoke to a friend recently and heard a new term called the “Smart Grid.” Sounds like a new kind of computer game, if you ask me. In short, the term Smart Grid has been used to describe recent improvements and upgrades to what is ambiguously known to the average electric consumer as “the grid” – that is, all of the infrastructure including generating plants, transmission lines, substations, distribution lines, switches, meters, etc. that are responsible for delivering reliable electricity to our homes.

There are many benefits to improving the grid, but from a consumer’s perspective, all we want is for the lights to be on when we need them, the water to be hot when it’s time for a shower, and the television and computer to turn-on when we want to use them. If it weren’t for the fact that I work in the utility industry, I personally would probably have no interest in learning about what the Smart Grid can do for me. Just keep the lights on and I’m happy. But, seeing as my job is to help educate our membership about how to use energy more efficiently, I think it is important for everyone to understand the basics, and if nothing else, understand how the Smart Grid can help you to save energy and money.

Right now, when you receive your electric bill, you are paying for energy that has already been used. This makes it very difficult to be pro-active if there is in fact an item in your home using more energy that it should or to change your habits to use less energy in a month where there is a rate increase. By employing Smart Grid technology, Pioneer is working to soon offer you the option of pre-payment in addition to online access to your energy use information. If you choose, it can be as simple as paying $200 to your account and having access to an in-home display or online portal that allows you to watch on a daily, or perhaps hourly basis, as the items in your home consume energy and chip away at your $200 payment. No more waiting a month to discover that your well pump is broken or the emergency heat has been stuck on for your heat pump or geothermal furnace. Parents can now help their kids see the monetary consequences of leaving lights, TVs, games, and computers on in real-time. And for the enginerds (read “engineer + nerds”) out there, we want to give you all the data you could ever dream of having to do your own home energy evaluation.

So, if you hear us mention “Smart Grid” in the future, know this – it is a tool that can be used to help you understand and thus manage your energy use if you take the time to understand it. We will still work to make sure we keep the lights on, but we can help you learn how to use energy more wisely, too.

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Heat Pump Water Heaters

Alice Camp of CRN - January 2011

New Heat Pump Water Heaters May Signal Rebirth of an Energy-Saving Technology

Cold showers aren’t a pleasant way to start the day, and hot water plays a hefty role in cooking and cleaning too. As a result, water heating has become the second largest user of energy in an average home, accounting for approximately 20 percent of residential energy consumption.

To save energy, consumers have wrapped water heaters in blankets or wrapped hot water pipes in insulation. While those practices should continue, a new type of water heating product is entering the market, promising to lower energy consumption and save consumers money.

Heat pump water heaters, while not a new technology, are experiencing a rebirth. A handful of small companies produced units in the 1980s and 1990s. But random failures and other issues (such as the need for utilities to install special electric service to power the devices) soured consumers on the technology.

In addition, many electric cooperatives offered (and still offer) load management programs that depended on briefly shutting off standard electric resistance water heaters (which can store hot water for many hours) as a way to cut electric use during times of peak demand when power prices skyrocket. These programs, in turn, helped cooperatives keep electric bills affordable. Heat pump water heaters, unfortunately, could not be used in these efforts.

Now, some major water heater manufacturers and other appliance companies have entered the market with a new and improved generation of heat pump water heaters. Many electric cooperatives, including Pioneer in conjunction with Buckeye Power, are currently testing these products for possible deployment in their service territories — a critical step in determining whether they will really help consumers save energy and trim electric bills.

How they work

Heat pump water heaters come in two types. The more expensive “integrated” model replaces an electric resistance water heater with one that combines a heat pump with a storage tank. The second version adds a heat pump unit to an existing electric water heater.

In both versions, a heat pump circulates a refrigerant, which absorbs heat from surrounding air before it passes through a compressor to maximize heat output. Essentially, heat drawn from the air transfers to water in the tank.

While a heat pump water heater can produce most of the hot water a family requires, a backup electric resistance element in the tank takes over when outside air becomes too cold or when consumers need extra hot water. In summer, cool exhaust air can be released into the vicinity where the heat pump water heater is located, assisting home cooling, or it can be returned outside via ducts.
Because a heat pump water heater uses electricity to move, rather than generate, heat, it consumes roughly half the electricity of a conventional electric resistance model. This efficiency qualifies integrated heat pump water heaters for an Energy Star rating, a first for electric water heaters.

But this added efficiency comes with a high price tag. Integrated units sell for $1,400 to $2,000 — more than twice the cost of standard electric resistance water heater. Depending on your cooperative’s electric rate and the installed cost of a heat pump water heater, including any financial incentives, payback for the purchase can take as little as three years. In areas with low electricity rates and limited financial incentives, though, the payback period can be much longer.

Heat pump water heaters are most efficient in warm and damp climates. Homes in those regions also benefit from the appliances’ cooling and dehumidifying features.

A heat pump water heater needs space of at least 10 feet square to ensure adequate air exchange. An open basement, a utility room or — in some areas — a garage will work.

Noise becomes another consideration when deciding where to place a unit. While conventional electric resistance water heaters operate quietly, most heat pump water heaters boast noise levels similar to window air conditioners.

Heat pump water heaters are not a universal option. Residents in colder climates will see decreased performance during winter. In the Pacific Northwest, for instance, if the heat pump is designed to work at ambient air temperatures of 45°F or higher, the water heater’s electric element will operate whenever air temperatures drop below that level, reducing energy savings.

To learn more, visit www.energystar.gov and search for heat pump water heaters.

Alice Clamp is a technology writer for the Cooperative Research Network. The mission of the Cooperative Research Network is to monitor, evaluate and apply technologies that help electric cooperative utilities control costs, increase productivity and enhance service to their consumer-members.

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Helpful Hints In Selecting Windows

Ted Riethman & Meghan McGuire Denlinger- October 2010

Windows aren’t just holes in your house to see the world through anymore, but can be a very attractive addition to any home. When selecting windows for a home there are a few things you need to pay attention to, so you get the most energy efficient units for the home. Windows are less resistant to heat flow compared to the walls, ceiling and floors in your home, meaning they will allow more outward heat flow in the winter and more inward heat flow in the summer.

Even though windows typically comprise a small surface area of a home they can significantly contribute to heat loss and gain in a home. Selecting the most efficient windows for your budget can make a difference in the overall comfort and operation of the home’s heating and cooling system.

Men and women tend to take a different approach to window selection and must weigh the pros and cons of window appearance, required maintenance, how they open and how they are installed. All are important aspects of window selection, but how do you know if they are energy efficient?

Where do you look for indicators of energy efficiency on a window? The National Fenestration Rating Council (NFRC), www.nfrc.org, has developed a window rating system based on the whole window performance. There should be a label located on the window showing the rating of the window. The label should have the U-factor rating, solar heat gain coefficient rating (SHGC) and visual transmittance (VT), as well as the Energy Star label, if it qualifies.

Windows are not rated by R-value like wall insulation, but by U-factor. The U-factor is the reciprocal of the R-value (R=1/U). The larger the U-factor the greater the heat flow through the window, therefore a lower U-value equals a higher and better R-value. The U-factor should read .35 or lower to get the best results. Solar heat gain coefficient rating (SHGC) relates to how well a product blocks passive solar gain to the interior of the home, which is especially important in heating dominated climates. This number is expressed between 0 and 1; as the rating gets closer to 1, more solar heat is transmitted into the home. You must be careful not to get the number too high or it will negatively affect the cooling load of your home. Visible transmittance (VT) is the optical property of the window and does not affect the heating and cooling loads of the home. This number changes based on the type of glazing placed on the window. This feature is rated between 0 and 1; as the number gets closer to 1, it lets through more visible light which in turn can affect how fast colors fade/change on furniture and carpets. The ENERGY STAR® label ensures the window is energy efficient and has met certain U.S. Department of Energy and Environmental Protection Agency energy performance criteria, making it easy for consumers to make cost effective decisions.

When selecting windows, do your homework, talk to building contractors, check out literature and visit websites to get all the correct information.

If you think your windows are the reason for your high energy bills, first make sure they were put in correctly by checking to see they are completely insulated around the rough opening of the window. This may require removing some trim but the majority of homes in our region have little to no insulation or the proper caulking needed to seal the frames of the window. This is often what causes a drafty feeling around the window openings. Because windows are such alarge investment when it comes to replacement, making sure they are installed and insulated properly can go a long way in resolving comfort issues.

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Crawlspaces - To Vent or Not to Vent?

Meghan McGuire Denlinger- June 2010

For home-owners looking to make cost-effective energy efficiency improvements in their homes, often all they need to do is look under their feet. After two years of investigating crawlspaces that are 10 years old to 100 years old, my experience has shown that most homes with first floor comfort issues, indoor air quality problems, and high energy bills often have wet, poorly insulated crawlspaces. The good news is that comfort, healthy air, prolonged building durability, and energy savings can be achieved. The bad news is that there isn’t one approach that will work for every home based on the variables of exterior moisture sources, location and type of heating systems and water heaters, and moisture content and possible degradation of building materials.

There is much debate among building science gurus over best practices in insulating and air sealing crawlspaces, but here are some of the items that remain consistent: 

1. A passively “vented” crawlspace, while built in accordance with local building codes, is typically cold in the winter and moist and possibly moldy in the summer. Relying on Mother Nature to remove warm moist air in the summer typically leads to condensation on ductwork, mold growth, and a damp smell in crawlspaces. Improperly sealed vents in the winter can lead to uncomfortable floors, frozen plumbing, and wasted energy. Sealed and insulated crawlspaces or “mini-basements^a” have been tried and tested in many climates and typically result in improved comfort, prolonged durability of building materials, and improvement in indoor air quality.
2. Is the crawlspace dry? If there is standing water under the house when there is rain, this probably means the drainage around the house needs to be addressed. Causes of bulk moisture accumulation can be attributed to poorly installed or disconnected downspouts, insufficient grading of the soil away from the foundation, and clogged, crushed, or missing drainage at the foundation. If you opt to dig up the outside of the foundation to improve damp proofing and drainage, then the most cost-effective approach is to insulate the exterior^b of the crawlspace at the same time (assuming this is a block or poured wall). Search for a borate-treated foam board, or have the foam treated to deter pests, then cover with a protective coating such as flashing, fiber cement board, parging, treated plywood, or membrane material. If you have an older home with a rubble foundation wall^c, sprayed polyurethane foam applied to the exterior and protected by a stiff metal flashing is the only exterior option. Check with your local building code to see if clearance needs to be left for termite inspection.
3. Are there any atmospheric or “natural” draft heating or water heating appliances in the home? A crawl space with atmospheric or “natural” draft equipment should not be sealed^d. Ideally, any fuel-fired furnaces or water heaters in a closed crawl space should be of a “direct vent” or “two-pipe” design, meaning that all air for combustion is piped directly from outside into the appliance and all combustion exhaust gases are piped directly from the appliance to outside. Changing the air-tightness of a home with atmospherically drafting appliances can unintentionally change pressures in the building and lead to dangerous CO back-drafting of these appliances. Ideally, only sealed-combustion, high efficiency heating and water heating systems should be used in homes pursuing high levels of air-tightness.
4. Regardless of how the crawlspace is insulated, you should install a sealed polyethylene barrier on the ground that continues up the wall to eliminate moisture from the ground migrating into the crawlspace. Seams should be taped, and care should be taken to cover areas around columns and corners that typically get ignored. A poured slab is also a more costly but more durable option.
5. Similar to a basement, insulating and air sealing the rim joist/band board^e is a must. Sprayed polyurethane foam installed by a contractor or rigid foam cut to fit each rim pocket and secured with one part foam or caulk is best practice. Using fiberglass batts encourages mold or rot because moisture migrates behind the fiberglass and condenses on the cold rim joist in the winter.
6. Are mechanical systems and ductwork located in the crawlspace? If yes, it is most cost effective to insulate the crawlspace walls therefore bringing all of this equipment, including plumbing, into the conditioned space of the house. Essentially you create a mini-basement. Attempt to achieve R-13 with foam insulation board securely attached to the walls with a combination of adhesive and/or mechanical fasteners. Or hire a contractor to install closed-cell spray foam on the interior wall. Check your local building codes to see if a fire barrier is required. If so, DOW-Thermax is a fire rated foam board available by request at your local home improvement store or lumber yard.
7. Communicate with you local code official early on in the game. While creating an unvented crawlspace is by no means new technology, it is a somewhat new practice to our region. Your code official may need help understanding your overall goals and how these goals will help improve the durability, safety, and efficiency of your home. Remember, a crawlspace is just a mini-basement, and we don’t leave the windows open in our basements!
8. Test for radon after all work has been done. A radon mitigation strategy may need to be installed.

Inconsistencies in belief and practice – even the experts don’t always agree: 

1. Your code official may want the crawlspace to be vented even after it is sealed. Adding a supply duct dedicated to the crawlspace is one way of “venting” this space and helping to keep it dry. However, some building scientists argue that this is wasted energy and doesn’t need to be done. If you choose to pressurize the crawlspace, make sure the walls are insulated and not the floors.
2. Insulate the floor with fiberglass. Typically gravity is not your friend with this insulation method, and over time you end up with insulation laying on the ground and not helping keep heat from escaping through your floors. Yet, this method of insulating is still one of the most popular methods. One leading building scientist argues that adding insulation to floor joists^f keeps heat from the first floor from warming and thus drying floor joists, and eventually leads to water droplets forming on the exposed surface of insulation and the floor joists. While wood can withstand some wetting, typically wood + water = mold = decay, especially wood containing glues like OSB.
3. Leave a space for termite inspection. Some say yes, some say no. One Pioneer member called a pest control company to ask, and that representative said termites like rotten wood. Keep the wood dry, and you shouldn’t have to worry about termites.

^a Lstiburek, Joseph. “BSI-009: New Light in Crawlspaces.” www.buildingscience.com, 2009/05/22.
^b Building America, US Department of Energy. “Builders and Buyers Handbook for Improving New Home Efficiency, Comfort, and Durability in the Cold and Very Cold Climates.” www.buildingamerica.gov, 2005/08.
^c John Krigger & Chris Dorsi.  The Homeowner’s Handbook to Energy Efficiency. Saturn Resource Management, Inc., 2008.
^d Advanced Energy. “Closed Crawl Spaces: An Introduction for the Southeast.”www.crawlspaces.org, 2005.
^e Building Science Corporation. “Info-408: Critical Seal (Spray Foam at Rim Joist).”www.buildingscience.com, 2009/09/18.
^f Lstiburek, Joseph. “BSI-009: New Light in Crawlspaces.” www.buildingscience.com, 2009/05/22.

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Prioritizing Energy Savings Investments

Meghan McGuire Denlinger- May 2010

With energy prices on the rise, it seems everywhere you turn you can find a list of “100 things you can do to save energy.” However, if you are ready to take some bigger steps to save energy in your home, a general rule of thumb is the bigger the usage, the bigger the savings. That is to say, hunting down and addressing the biggest energy usages in your home generally will have the biggest return on your investment. The question remains, where should you begin a home retrofit project?

First and foremost, you will want address indoor air quality and health and safety issues. If your basement is constantly wet, understand that if you choose to do any air sealing you could have a potential mold issue. Addressing foundation leaks, re-grading soil away from your home, installing a French drain, and/or making sure your downspouts direct moisture away from the home are top priority.

Next, plan on addressing the building shell. Make an appointment with your cooperative’s Energy Advisor to set up a blower door test. Using this diagnostic tool, along with an infrared camera, the Energy Advisor will help to identify where energy to heat and cool your home is escaping through air leaks and insufficient insulation. In our climate, strategic insulating and air sealing are the most effective methods for saving energy.

Once you’ve stopped the leaks in your home, consider replacing an inefficient HVAC system. If you have an old system that is rated 70% to less than 92% efficient, you have the potential to save 20-25% on your heating usage by replacing that system with one that is 92% or more efficient. The most efficient mechanical method of heating and cooling a home in our climate is with a geothermal heat-pump system. With efficiencies as much as 300%, it’s like receiving $3.00 worth of energy out-put for every $1.00 of energy input. However, due to the high installation costs, geothermal is a better option for homeowners that live in homes with large heating and cooling loads, and if the homeowners plan to stay at a location for 5-10 years. Also take the time to check out your duct work. Do you know if your duct work is located in the conditioned or unconditioned part of your home, and if it is located in an unconditioned part such as an attic, is it sealed and insulated?

Next, investigate your hot water usage. If you think you might have a hot water leak somewhere in your home, addressing this leak will have tremendous savings potential when it is found. Installing low-flow shower heads and sink aerators will help to cut back on hot water usage, along with setting your washer settings to warm or cold. Most laundry detergents are designed to work in any temperature, and colors will last longer if washed in cold water. When it comes time to replace your washer, consider a front loading Energy Star model. Some newer washers can use up to 11,000 gallons less of water per year, which means your well pump will work less and with better spin cycles that remove excess water, your dryer will have shorter drying cycles. Keep in mind that it is cost effective to replace a washer prematurely only if you have high energy or water costs, or if you do 2 or more loads of laundry per day, otherwise wait until your old unit no longer functions. Finally, consider installing a heat pump water heater to cut your hot water costs in half. While initially expensive to install and relatively new to the market, the heat pump water heaters look to be next energy efficient wave of water heating technology.

Finally, look into what is called your electric “baseload” consumption, or energy that is used for household items year round and is not affected by changes in the weather. Having a secondary old refrigerator can cost as much as $40-$200 extra per year. Switching from incandescent to CFL bulbs will cut your energy and maintenance costs for lighting by approximately 70% over the life of the bulbs. Turning off 24 hour items such as computers, lights, TVs, fans, etc. can save $10-$50 per year. Try installing timers with surge protection strips on entertainment centers and gaming systems, and you could save $50-$100 per year by eliminating the stand-by energy use of these energy vampires.

When prioritizing energy savings investments, remember that a little bit of planning can equal really big savings!

Prioritization adapted from a presentation given by Michael Blasnik at the Affordable Comfort, Inc. Home Performance Conference held in Pittsburg, April 2008.

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Grassroots Solutions to Global Issues: Energy Efficiency and Conservation is Key

Meghan McGuire Denlinger- April 2010

As Energy Advisor, I find it a bit paradoxical to try to explain the essence of my job to our members and others who have never heard of an electric cooperative. Yes, I work for an electric company, and yes, part of my job is to help people learn how to use less electricity. I challenge you to find any other company that encourages you to use less of the product that they produce or distribute. Indeed, it is our not-for-profit business model and the cooperative principles that allows us to do this. 

As a cooperative, we are dedicated to providing electricity that is affordable, reliable, and environmentally responsible. We recognize that it is hard to turn on the television, read the paper, listen to the radio, or surf the internet today without being bombarded with global issues such as climate change, severe weather events, political and social unrest, and soaring energy prices. All of these issues are truly a lot to take in over a cup of coffee in the morning. Yet, we hope we can assist you in managing your energy costs through our Energy Advisor program. In addition, we can also help support local businesses and help our members save on prescription costs with our Co-op Connections® Program.

In order to cope with global issues, I believe the best solutions are grassroots efforts. Many of you may be aware of the radio control system that Ohio cooperatives have been using to control peak demand some 30+ years. Before radio control switches and rate incentives, Ohio cooperatives were able to control peak demand by a long forgotten communication tool—the phone tree. Buckeye Power would issue a peak alert, and through land-line phone communication, members would manually and voluntarily turn off their hot water heaters until the peak had passed. The motivation for participating in this program was to help meet the needs of the cooperative by prolonging the need for constructing new peaking facilities, thus helping keep rates low – a prime example of grassroots efforts in action.

Fast forward to today where this same program is in place, except members have to do little but call and request that a radio control switch be installed on their water heater or central air unit, and we do the rest to control peak demands. Indeed, many of our processes have become automated, making everything from bill paying and outage reporting as easy as the click of a few buttons. But is all this automation enough to fend off the rise in future energy costs?

At the end of the day, your purchasing decisions and daily habits have a huge impact on the amount of energy you use, the amount of money you can save, and how your cooperative will manage its costs to provide you power. Will you unplug that extra fridge in the garage? Will you turn down the thermostat on your hot water heater to 120°F? Will you opt for a super efficient geothermal system to heat and cool your home? Will you choose the best air sealing and insulation package when you build a new home? Will you always buy Energy Star appliances? Will you switch out your incandescent light bulbs for CFL bulbs? As Energy Advisor I am here to assist you in making decisions to help manage your energy costs, and thus benefit your fellow cooperative members as well.

Email your Energy Advisor your comments.