When researching energy efficient appliances, we often turn to the recommendations of the American Council for an Energy-Efficient Economy (ACEEE). The ACEEE continues to publish helpful information about all sorts of appliances, including freezers. The ninth edition of their Consumer Guide to Home Energy Savings, published in fall 2007, contains helpful information about selecting a freezer.

The most efficient type of freezer is the chest freezer. This is because a chest freezer opens from the top, and cold air (which is heavier than warm air) does not escape easily from a chest freezer. The weight of the lid also helps to seal chest freezers tightly. Chest freezers are 10% to 25% more efficient than upright freezers.

A useful thing to know about U.S. freezers is they’re almost all manufactured by three companies: Frigidaire (owned by Electrolux), W.C. Wood (based in Canada) and Haier (based in China). Frigidaire makes freezers under the Frigidaire and Gibson names, and makes some freezers for Kenmore and GE. W.C. Wood makes freezers for Amana, Magic Chef, some units for Maytag, Danby and Whirlpool. Haier makes freezers for GE, Kenmore, some units for Maytag and Amana in addition to selling some models under its own name.

Because of the different branding, many times customer are paying a premium for a differently branded freezer. For example, Frigidaire freezers sometimes cost more than GE freezers and Maytag freezers may fetch a premium over a W.C. Wood freezer.

Recently, the US Department of Energy launched the Recycle My Old Fridge campaign that encourages Americans to recycle their old, inefficient refrigerators. The web site includes a calculator so users can determine how much energy their current refrigerator consumes, what they can save by replacing it with a new Energy Star model, and where they can take the old fridge to be recycled locally.

Here’s a look at the most efficient chest freezers currently available:

Whirlpool Chest Freezers

Whirlpool Chest Freezer: Energy Star Qualified

Whirlpools makes a very energy efficient chest freezer, model number EH151FXR (similar models are EH151FXQ or EH150FXQ). This 14.8-cubic-foot freezer is rated at 354 kWhrs per year. The average cost to run this freezer for year is $29, according to Energy Star.

Though it requires manual defrosting, it sport a number of other features including an interior light and a temperature alarm. Its key-eject lock means that the freezer can only be opened when the key is pushed in and turned — a safety feature helpful in homes with small children. Four baskets (two upper, two lower) make it easier to organize the contents — especially on the lower level.

It’s available from Amazon for $405.

Sundanzer DC-Powered Chest Freezers

Sundanzer DC Chest Freezer

The most efficient DC-powered chest freezer is the SunDanzer. This eight-cubic-foot capacity freezer has an exceptionally low energy consumption — it uses around 140 kWhr / year. It incorporates the highly efficient Danforst compressor. It also has a super-insulated cabinet that is wrapped in four inches of polyurethane. Because it runs on either 12 or 24 volts DC, the SunDanzer freezer is mostly used in off-grid homes or in remote locations, because a 75 watts solar panel and and two six-volt golf cart batteries can power the freezer.

It’s available from the Alternative Energy Store

At MetaEfficient, I evaluate appliances based on a number of factors, namely: energy efficiency, effectiveness, reliability, and price. This holds true for washing machines, because all of these factors need to be considered and weighed against each other (I’d also like to include lifecycle analysis, but  there’s no information available for washers). For raw efficiency data, one can turn to the Energy Star ratings, to work out which machines use the least amount of energy and water overall. Based on the Energy Star data, the most efficient washing machines for 2008 are made by LG Electronics and Kenmore.

Three LG washers received the best Energy Star ratings, and four Kenmore washers followed very close behind the LG machines. These ratings are based on the Modified Energy Factor (MEF) which is a way to compare the relative efficiency of different units of clothes washers (higher is better). The second factor is the Water Factor which is the number of gallons per cycle per cubic foot that a washing machine uses (lower is better). Here is a listing of the highest rated washing machines according the February 2008 update:

1. LG Electronics TROMM SteamWasher WM248#H, 2.65 (MEF), 3.6 (Water Factor)
2. LG Electronics Stainless Steel SteamWasher WM0001H: 2.65 (MEF), 3.4 (Water Factor)
3. LG Electronics TROMM SteamWasher WM268#H: 2.65 (MEF), 3.3 (Water Factor)
4. Kenmore Washer Model 4757*70+: 2.6 (MEF), 3.7 (Water Factor)
5. Kenmore Washer Model 4756*70+: 2.6 (MEF), 3.7 (Water Factor)

(Model numbers often contain wildcard characters, such as *, #, and X, that are placeholders for non-energy attributes, such as color. )

In this analysis, I’m excluding Energy Star washers with a load capacity of less than 3 cubic feet, these compact machines get high energy ratings but are inefficient in their water use.

You’ll notice that all of these machines are front-loading washers, the ConsumerSearch product review guide says:

Experts generally agree that front-loading washing machines (also called horizontal-axis washing machines) are better than top-loaders. Front-loaders use a dryer-like action to tumble clothes in and out of water and detergent, while conventional top-loaders circulate clothes with some type of agitator. Because gravity is used to tumble the laundry, front-loaders are gentler on clothes and cause less tangling than top loading machines. In addition, their fast spin speeds remove more water from clothing, thereby reducing drying time and resulting in further energy savings. Because of the design, you can’t soak clothes and you have to use special low-sudsing “HE” or high-efficiency detergents.

Let’s look at the most efficient washers in more detail, followed by an efficient washer we think is the best value for your money:

LG TROMM SteamWasher

This is an innovative washer: it uses stream to wash your clothes, and this process makes it the most efficient washer available. The steam cleaning is gentle on your clothes, and tend to remove wrinkles. The washer uses only 145 kWh of energy per year, and 4,690 gallons of water per year on average. This is significantly better than conventional washers. The SteamWasher is also the largest capacity front-loading machine with 3.63 cubic feet of space. It can spin your clothes at 1200 rpm, which means you’ll save on drying energy and time. The problem with this washing machine is that it’s expensive. It has a recommend price of $1600, and most retail stores sell it for around $1400 currently. A better option might be to get a lower cost but still very efficient LG machine (see our review of one below).

In terms of reliability, ConsumerSearch says: “The LG TROMM SteamWasher hasn’t been on the market long enough to establish a reliability track record, but the J.D. Power’s major appliance study showed that LG washing machines in general have the highest customer satisfaction rating of all brands.”

The LG TROMM SteamWasher is available from Sears.

Kenmore High-Efficiency Washers

The Kenmore “High-Efficiency” washers live up to their name, and have a reasonably good track record in regards to reliability. The Kenmore machines use 69% less water and 60% less energy per load compared to conventional top load washers. They also spin at 1000 rpm, which means less energy will be spent drying your clothes.

The Kenmore front-loading washing machines are priced at $600-$900, and only available from Sears.

LG Supercapacity Front Load Washers

LG Electronics makes less expensive washing machines that are also highly efficient. For example, the front-loading LG WM0642HW (estimated retail $850) gets good reviews. It’s more affordable because it has fewer bells and whistles, and because it has a small door and window. The LG WM0642HW has a 3.83-cubic-foot capacity, automatic temperature control, an automatic detergent dispenser and a stainless-steel tub. A similar model, the LG WM2016C (estimated retail $780), costs a bit less, but is slightly smaller, with a smaller window.

The LG WM2016C gets a Modified Energy Factor (MEF) rating of 2.25, which is quite good — this machine will only consume 152 kWh / year, and 4323 gallons of water per year on average. That’s only 7 kWh more energy per year than the SteamWasher, and 367 more gallons of water, for half the price. Because of this, the LG WM2016C is the MetaEfficient recommendation for an efficient washing machine.

These LG washers are available from Amazon and Sears.

In terms of quality, cost and energy efficiency, Kenmore refrigerators get high ratings from Good Housekeeping and Consumer Reports. They make many “no-frills” refrigerators which are Energy Star compliant. Kenmore fridges have factory-installed ice makers, which are less prone to break down than those built into the door. For example, a reasonably priced, mid-sized Kenmore fridge is available from Sears for about $430. In my experience as an owner, however, I’ve found that Kenmore shelves and drawers tend to break very easily.

Top-freezer and bottom-freezer refrigerators are more energy efficient than “side-by-side” models, and they are less expensive. See this report from the Green Guide, for a list of the best Energy Star compliant refrigerators.

If you are looking for highly efficient refrigerator, look for models from Avanti and Sunfrost. These fridges are best if you are looking for great energy savings, or if you are off-grid and using solar power.