Microsoft builds Hohm, a new energy-monitoring system

Months after Google rolled out its PowerMeter energy-monitoring service, Microsoft has unveiled Hohm, its own free service designed to let you access, analyze, and optimize energy use through links to utilities and vendors of energy-efficient products and services.

"If you break up the energy-consumption sector in the Untied States, you'll see residential is the most underserved," says Troy Batterberry, Microsoft Hohm's product unit manager. "Commercial and industrial sectors have had the ability to hire experts to help them drive down energy costs, but most residential users haven't had an easy-to-use, inexpensive tool to help them do the same thing."

The service, a beta version of which launched on July 6, takes its name from home and ohm, the unit of electrical resistance. "We wanted a short name with a unique spelling so users could find it very quickly via Web searches—but it's also a nod to the electrical-engineering profession," Batterberry says. I guess Hohm sounds better than Holt (home and volt), Hampere (home and ampere), Hurrent (home and current), or Hatt (home and watt).

If you have a Windows Live ID, you can use your existing login to access Hohm; otherwise, you need furnish only your Zip code and e-mail address to gain access. After joining, you'll get a screen with a pie chart showing the average breakdown of energy consumption in your area, based on information Microsoft has licensed from the Lawrence Berkeley National Laboratory and the U.S. Department of Energy.

And if you're a customer of one of Hohm's four current utility partners—Seattle City Light, Puget Sound Energy, the Sacramento Municipal Utility District (PDF), and Xcel Energy (PDF)—you'll get a comparison of how your annual energy costs rate against other homes in the area.

Weekend Project: Tune up your air conditioning

If you haven't done it already, now's the time to get your air conditioning tuned up and installed for summer. Use these tips from Consumer Reports and RepairClinic.com to ensure peak air-conditioning performance when the mercury rises. And if you're in the market for new air conditioning, read "Financial Incentives Could Make Air Conditioners a Hot Buy."

Window, Portable, and Through-the-Wall Air Conditioners
Clean or replace filter(s). Remove the filter(s) and vacuum off debris. You can wash a dirty filter in warm, soapy water; be sure it's completely dry before you reinstall it. (Some filters are washable but check the user manual for care recommendations.) If a filter is damaged or deteriorated, replace it. (Take an old one with you to the store to ensure you buy the right model and size.) If you can't find the specific replacement filter you need, buy filter material and cut it to fit. Clean the filter once a month during cooling season.

Vacuum the coils. Vacuum any debris from the indoor and outdoor coils with an upholstery-brush attachment before you install a room air conditioner. Take care not to damage or deform the soft fins. Specially designed fin combs work much better than screwdrivers at straightening out bent fins.

Then remove the unit's cover and use soft brush or a can of compressed air to remove dirt from the inside of the coils and the bottom of the air conditioner.

Install and seal the unit(s). Air conditioners installed in a shady spot could run up to 10 percent more efficiently, according to the U.S. Department of Energy. Seal the perimeter of the installed unit with new weather stripping, if needed. Also, secure the unit so that a burglar can't push it in and, more important,  so that it can’t fall out of the window and injure someone.

Avoid "short cycling." Wait 10 minutes after shutting off the unit to restart it. This allows the pressure in the refrigeration system to equalize and will prolong the life of your air conditioner.

Central Air Conditioning
Call in a pro. Have a licensed professional perform key maintenance tasks, including changing all filters, cleaning and flushing the coils, draining the pan and drainage system, and vacuuming the blower compartments. The contractor should also check that the system is properly charged with refrigerant, that there are no leaks, and that all mechanical components are working properly. As with a room air conditioner, replace disposable filters regularly. Check them monthly and replace if dust and debris have completely coated the filter.

Insulate ductwork. Ensure that ducts throughout the system are sealed and insulated—up to 30 to 40 percent of your cooling energy can be lost through leaks or heat when uninsulated ducts pass through uncooled spaces like attics and garages.

Perform seasonal checks. During the season, keep vegetation at least two feet away from the unit. Clean the grills and filter(s) monthly and replace the latter as needed. Clear debris and dirt from condenser coils and check for blockages in the pipe that drains condensed water from the indoor unit.

Use a programmable thermostat. Proper use of a programmable thermostat can reduce your cooling costs by up to 20 percent. Also consider adding a ceiling fan, which will allow you to set your thermostat to a higher temperature. And find more ways to cut your cooling costs.—Gian Trotta | e-mail | Twitter | Forums | Facebook Essential information:

Essential information: Our latest report on air conditioning (story and ratings available to subscribers) covers split-ductless systems and portable air conditioners and includes reliability information on brands of central air conditioning.

Buzzword: Cool Roof

What it means. Never heard of a "cool roof"? Abandon your visions of an overhyped hipster-filled rooftop bar or eatery in an edgy, funky neighborhood. A cool roof, simply put, is a roof designed to reflect sunlight. Since the roof stays cooler, less heat is transferred to the building below, resulting in a cooler building and energy and money savings.

Why the buzz? U.S. Secretary of Energy Steven Chu recently made headlines when he was in London to attend a symposium on climate change. He said that painting all roofs white or light colors could help significantly reduce the amount of energy used to cool buildings.

But this idea is about not only the color of a roof but also its solar reflectance (SR) and thermal emittance (TE), which are rated on a scale of 0 to 1, with 1 being the most reflective or emissive. The Cool Roof Rating Council trade group says it rates products based on their initial values and after three years of weather exposure. The cool-roof concept is to use reflective coatings or materials. So a cool roof could be made of clay or concrete tiles or other materials suitable for a climate along with coatings in a range of colors that are designed to reflect the rays of the sun. The photo shows a home with MCA clay roof tiles in Riverside, California.

Cool roofs lower the surface temperature of a roof by up to 100*F, according to the California Energy Commission, which estimates that cool roofs can trim cooling costs by 20 percent on average in California. The CRRC estimates the average energy savings are 7 to 15 percent of cooling costs.

But the U.S. Department of Energy says that reflective roofs don't work in all situations, and the biggest benefits are reaped in hot, sunny climates where air conditioning is used frequently. Homes in shady spots or those with well-insulated attics might not see significant benefits. Cool roofs can also increase heating costs in the winter. To figure out how much energy you'll save, use the DOE's cool-roof calculator.

If you are considering a cool roof, find out whether the materials qualify for a federal tax credit and request a manufacturer's certification statement. You could receive a 30 percent tax credit (up to $1,500) for the material costs if the roof is installed this year or next. Also look online for rebates from utility companies.—Kimberly Janeway | e-mail | Twitter | Forums | Facebook

Essential information: Check out our June 2009 report on roofing and July 2009 report on air conditioning (available to subscribers), stay cool without sky-high energy bills, and read about ceiling fans.

Financial incentives could make air conditioners a hot buy

If you need new air conditioning, the higher-efficiency models you'll find in stores combined with some financial incentives might make this a good time to buy.

Before you shop, use the information below and check out our latest report on air conditioning, which includes coverage of split-ductless systems and portable air conditioners and updated reliability data for central air conditioning (report and ratings available to subscribers). And watch our video buying guide (below).

Window and Through-the-Wall Air Conditioners
Available incentives: The Database of State Incentives for Renewables & Efficiency lists 67 utilities in 20 different states that offer rebates on Energy Star-qualified air conditioners. Rebates vary from $15 to $150. They're generally more generous for higher-Btu machines and in the Sun Belt. Window air conditioners don't qualify for federal tax credits. Six states also offer sales tax holidays on Energy Star appliances. Watch for manufacturer rebates and store sales and don't be shy about haggling.

"We're not only trying to save the customer money but also hold down peak demand so we you don't have to build new power plants," says Ed Clark, director of communications for Austin, Texas-based Austin Energy. "Our average customer uses 46 percent of their annual electricity usage from June to September."

Why replace? If your air conditioner is more than nine years old, it might make sense to replace it. The latest Energy Star-qualified models use about 25 percent less power than ones made before late 2000. The U.S. Department of Energy estimates you'll save an average of $75 in energy costs over the appliance's lifetime. Use our free online calculator to determine how big an air conditioner you need.

Split-Ductless and Central-Air Systems
Available incentives: Some of the split ductless models we tested (like the one shown) have a seasonal energy-efficiency ratio (SEER) above 16, which qualifies them for a 30 percent a federal tax credit. Labor is included, but the credit is capped at $1,500.

Utilities in 26 states have rebate programs for split ductless and central-air systems with a SEER between 14 and 17. And 30 states also offer low-interest loans for a split-ductless or central-air system.

Why replace? New central-air-conditioning systems are 20 to 40 percent more efficient than those made a decade ago. Also, repairing an older systems can be expensive. However, if your system is in good condition, you'd be better off sealing leaks in the system and insulating any ductwork that passes through uncooled spaces. These improvements can save you up to 40 percent of your cooling bill.

If you're tired of the hassle of installing air conditioners but don't have room to run ducts, consider a split-ductless system. The units we recently tested provided excellent cooling performance and were much quieter than window-mounted air conditioners. Prices have also fallen in the last few years. We tested models ranging from $1,000 to $1,200 that could cool an average room. To cool multiple rooms, you'll need multiple evaporators (the fan and cooling coil unit mounted in each room). Each evaporator requires its own condensing unit outdoors, though some brands offer models that can connect to several evaporators. All this equipment can make the cost climb quickly so it typically makes the most sense to install a central system when cooling the entire home.—Gian Trotta | e-mail | Twitter | Forums | Facebook

Essential information: If your local utility rebate is taxable (you'll get a Form 1099 from the utility), then you can put in for the full cost of the air-conditioning system. If the rebate is not taxable, then you have to subtract the rebate amount from the total cost of the system before you figure out your federal tax credit.

Negligible cooling nets Cool Surge portable air cooler a Consumer Reports Don't Buy judgment

You can buy a decent small window air conditioner for as little as $140, as we found in our July 2009 report on air conditioning (available to subscribers). Or you can spend more than twice that amount—$298—for the Cool Surge portable air cooler (shown), which promises to cool an average-sized room "up to ten degrees" using the same energy as a 60-watt lightbulb. (Watch our exclusive video, below.)

The Cool Surge might sound appealing when you consider the roughly 500 watts needed to run even a small air conditioner. Ohio-based Fridge Electric LLC, which markets the Cool Surge, has even offered a two-for-one deal in full-page ads in The New York Times and other newspapers. But our tests show that when it comes to cooling a room, the Cool Surge is likely to disappoint you at any price.

The Cool Surge is essentially an evaporative cooler (also known as a swamp cooler) that bases its cooling claims on a concept thousands of years old. The unit's reservoir holds about a gallon of water and two reusable ice packs like the kind that go into lunch boxes and picnic baskets. The chilled water wets a curtain inside, and a fan moves air through it much the way a breeze would blow air through moistened fabric centuries ago. No compressor, no condenser, no refrigerant gas.

Could that ancient principle cut it in today's "average" room? Consumer Reports tested two samples of the Cool Surge in the same lab we use to test air conditioners. At just over 200 square feet, our test room is actually a tad smaller than the roughly 227-square-foot living room in a typical new home, and, therefore, should be easier to cool. We controlled conditions around the room to simulate an 85°F dry summer day with a relative humidity of just 57 percent.

As we found, the phrase "up to" in Cool Surge's cooling claims does some heavy lifting: Our string of sensors showed the device failed to appreciably lower the room's overall temperature during a four-hour test.

We also tested the Cool Surge at an even drier, desertlike setting of 25 percent relative humidity, again, at 85°F. Even in these conditions, which are suitable for an evaporative cooler, we measured a mere 2 degrees of cooling during the four-hour test.

Because of its negligible cooling in our tests, we've given the Cool Surge portable air cooler our Don't Buy: Performance Problem judgment. (The Cool Surge has a built-in heater with a faux fireplace; we didn't test its heater nor did we test this product for safety.)

Confusing pricing policies and complaints about companies associated with Cool Surge also left us cold. The Cool Surge debuted in 2008 and was originally promoted by Universal TechTronics. The same company is a division of Heat Surge, which markets the Heat Surge Roll-n-Glow Electric Fireplace—also known as the Amish heater—and pushed a "free" DTV converter box that ultimately cost nearly $100 when you added in the mandatory warranty and shipping and handling fees.

We ordered the two Cool Surge units that we evaluated online and paid $298 for each, with no shipping charge. But when we later called the Web site's order line anonymously, we were told we'd have to pay $49 per unit for shipping, or nearly $100 if we had opted for the company's two-for-one offer. Another call using a different number listed in a Cool Surge newspaper ad yielded yet another price of $148 per unit—plus $49 shipping—for versions with "slight cosmetic damages." The two-for-one offer had apparently ended.

The Better Business Bureau warned consumers about Universal TechTronics' "misleading advertising campaign" for the DTV converter and gave the company an unsatisfactory rating based on its pattern of complaints. While the BBB says it has no complaints against Fridge Electric LLC, that company shares the same Canton, Ohio, address as Heat Surge.

A label on the Cool Surge units we evaluated referred to both Universal TechTronics and Heat Surge (shown). And when we checked the box, it listed all three names: Universal TechTronics, Heat Surge—and Fridge Electric.

We found no problems with the Amish heater in our evaluations earlier this year. But our research found that the Ohio Attorney General's Office had 55 complaints against Heat Surge that included the product and its marketer.

Bottom line: Buy an effective air conditioner if you want to cool a room; click here for the latest Ratings (available to subscribers). Or consider a fan if you want to save energy and feel cool from the blowing breeze; 20-inch models cost as little as $20 and use roughly 80 watts on their low setting—barely more than the 73 watts we measured for the Cool Surge on high.—Bob Markovich and Tod Marks | e-mail | Twitter | Forums | Facebook

Is there a link between central air conditioning and chronic disease? A new study hints at one

Think air conditioning, and you're likely to connect this modern amenity with the comfort it provides on scorching summer days. "The Relationship of Housing and Population Health: A 30-Year Retrospective Analysis," in the April 2009 issue of Environmental Health Perspectives, makes a different connection, suggesting a link between central air conditioning and chronic disease. The study connects the dots between the National Health and Nutrition Examination Survey (NHANES) and the Census Bureau's American Housing Survey (AHS).

(Note: Acting Surgeon General Steven K. Galson, M.D., M.P.H., on June 9 released "The Surgeon General's Call to Action to Promote Healthy Homes." Download a PDF of the call to action: Surgeon General Call to Action Healthy Homes 6-9-09.)

One key housing trend identified in the AHS is the increase in central air conditioning; in 2002, nearly 60 percent of U.S. households had a central-air-conditioning system, up from approximately 15 percent in 1972. In that same 30-year time period, the NHANES reveals how asthma rates more than doubled, from 3.4 percent to 7.8 percent, and the average body mass index climbed from 24.9 to 27.7; a BMI of 25 and above is considered overweight; 30 and above, obese. (See the charts, right and below.)

The study authors acknowledge that various risk factors contribute to weight gain and respiratory problems as well as other health issues, but they make a good case that air conditioning and heating are at least partially to blame. For one thing, there's the lifestyle impact. "The increase in central air conditioning and its associated improved thermal comfort could provide an incentive for people to remain indoors and thus exercise less and/or to exert less energy through lower metabolic rates," they wrote.

As for indoor-air quality, the authors contend that central-air systems "increase air velocities and resuspension of particulate matter" and reduce fresh-air introduction, since "windows that would otherwise be open in the warm months are more likely to be kept closed in the presence of central air conditioning." They also observe that air conditioning and closed windows can help reduce pollen and dust mite-inducing humidity in some environments.

Any broad-stroke study such as this one will have its caveats and counterarguments. The study's authors point out that television and junk food also contribute to changes in health. But this analysis takes the discussion of housing and health relationships beyond lead-based paint and other familiar hazards, especially as they relate to disadvantaged groups. Do the study's findings mean you should jettison your air conditioning? Probably not. But they're a good reminder that you should:

Maintain your forced-air system. If you have central air, change the system filter when it's dirty, maybe about once a month or so, to prevent dust from accumulating on the evaporator fins and being dispersed throughout the house. If your home has window air conditioners, clean the filters once a month. And during heating season, replace furnace air filters monthly.

Ventilate adequately. Exhaust fans in the kitchen, bathroom, and laundry area are best at expelling combustion gases, odors, and excessive moisture, which can breed mold and other allergens. In a temperate climate, turning off the AC and opening the windows on cool days can also help ventilate, provided there's not a pollution or pollen advisory in effect. Install a whole-house fan to expel hot indoor air and bring in fresh, cooler outdoor air when the weather is mild.

Exercise regularly. Good cardiovascular health not only keeps weight down but can also help prevent several chronic diseases, including hypertension and type 2 diabetes. During summer months, limit outdoor activity to before 10 a.m. and after 4 p.m. Review these additional tips for staying safe in the sun and read our latest report on sunscreens (available to subscribers).—Daniel DiClerico | e-mail | Twitter | Forums | Facebook

Essential information: Read our latest report on air conditioning and cooling your home (available to subscribers), which includes ratings of 29 window air conditioners and brand reliability of 11 central-air-conditioner manufacturers. And learn more about air purifiers and indoor air.

Home content in the July 2009 issue of Consumer Reports

With summer on the way, the July 2009 issue of Consumer Reports has all the information you need on keeping cool and saving energy and money, as well as articles on washers and dryers, laundry detergents, and deck stains. (Note that some reports and ratings are available only to subscribers.) Some highlights from the issue: 

Air conditioning
The video (right) shows how we test window-mounted and portable air conditioners and split-ductless systems. You'll also find brand repair history for central air conditioning. Don't forget about ceiling fans, which can help you beat summer heat and enhance the performance of your air conditioning.

Washers and dryers
An excellent washer or dryer used to cost $900; now you can take home a top-rated washer and dryer for about that same amount. Read our report on the latest laundry equipment and find out how to choose the right model for your home. We also tested Affresh to see how well it reduced the smell and mold that plague many front-loading washers.

Laundry detergents
Our latest report identified good high-efficiency (HE) and green detergents that cost as little as 17 cents per load of laundry. One CR Best Buy is specially formulated for cold water. It could save you up to $80 a year in detergent over the pricier brands and up to $60 a year in energy costs.

Deck stains
If our recent post on using a pressure washer helped you clean your siding or deck, you can finish the job by choosing the right deck stain. Our June 2009 report on exterior stains included some finishes that worked well on multiple outdoor surfaces. For this month's report, we've added ratings of nine more popular stains specifically formulated for decks.—Gian Trotta | e-mail | Twitter | Forums | Facebook

By the Numbers: Energy-related carbon-dioxide emissions declined in 2008

5.802 billion

Metric tons of carbon-dioxide emissions from fossil fuels generated in this country in 2008, down from 5.967 billion metric tons of carbon dioxide in 2007, according to new preliminary estimates from the Energy Information Administration. The 2.8 percent decline is the largest the EIA has measured since it has tracked CO₂ emissions. It's worth noting that even with this decline, since 1990, total U.S. energy-related CO₂ emissions have climbed by 15.9 percent.

The recession has been a major factor in the emissions reduction, as economic activity in this country has fallen off and demand for oil slackened. (Oil-related emissions slid by 6 percent year over year.)

Residential CO₂ emissions fell by 1.1 percent in 2008. Even though heating degree-days rose by 5.6 percent last year, the summer was cooler than in 2007, resulting in a cooling-degree-days drop of 8.7 percent.

Want to keep limit your own energy use? Check out our buyer's guide to air conditioning, use our calculator to determine how big an air conditioner you need, learn how to keep your cooling costs down this summer,  and read up on ceiling fans, portable air conditioners, and split-ductless AC systems.

Q&A: Should I install a whole-house fan?

I'm considering adding a whole-house fan at my home. How do they work, and in what parts of the country is it smart to use one?

Whole-house fans cool your home by pulling in cool air from open windows and exhausting warm/hot air through the attic and roof. (The illustration from the U.S. Department of Energy shows how these fans work.) They're ideal in areas with low humidity levels and typical nighttime temperatures below 75°F during the summer. Prices range from $200 to $800, and it's best to hire a pro to do the installation.

We recommend you choose a large-capacity fan, which will make less noise running at a low speed than a small fan will operating at high speed. Be sure the contractor installs the fan with rubber or felt gaskets to dampen noise.

Whole-house fans require an opening between the living space and the attic, but that opening can allow cold air to infiltrate your living space in winter. So if you live in a cold-weather climate, install an airtight insulated cover over the opening to prevent heat loss—and higher utility bills—during the winter. e-mail | Twitter

Essential information: Use our buyer's guide to air conditioning and read up on portable air conditioners, split-ductless cooling systems, and ceiling fans. And find out how to keep cool for less this summer. For more on whole house fans, download this PDF from the DOE: Whole-house fans.

Q&A: What is "split ductless" air conditioning?

I've been reading about "split ductless" air conditioning. What is it? And is it a good alternative to central air conditioning?

Split ductless is a smart way to add air conditioning to a limited number of multiple rooms without having to open up walls to install ductwork—as you would with a central-air system—or install and remove multiple window units each year.

Split-ductless systems have an exterior condenser and an indoor evaporator unit that houses the cooling coil, a fan, and controls, to which you can add indoor blowers. (The condenser and the evaporator blowers are connected by electric wires and tubing, through which the refrigerant circulates.) Some models are designed to have two or more evaporators connected to one condenser unit. Each evaporator blower is mounted high on the interior wall of the room or area you want to cool. You control the units with a remote control. Since you might have multiple units, you can save energy by zone cooling your home, as you might do with window air conditioners. A Mitsubishi Mr. Slim evaporator blower is shown.

For our upcoming report on air conditioning, we tested three split-ductless systems with single indoor evaporator units; the systems cost $1,000 to $1,200 each. All did an excellent job cooling and were much quieter indoors and out than window air conditioners; indeed, on the low setting they were barely audible.

Split ductless is more expensive than window or portable air conditioners (professional installation is recommended) but is less expensive than central air if you are cooling only a few rooms. However, if you are looking to cool the majority of your home, a central-air-conditioning system is probably a more cost-effective choice.

Look for complete coverage of air conditioning, including window, portable, and split ductless, in the July 2009 issue of Consumer Reports (online and on newsstands in June).

Essential information: Figure out what size air conditioner you need by using our free calculator and save money while staying cool this summer