Air Purification Week -- Sharp Air Purifier KC-C150U

Sure, you've heard of Fall Fashion Week, maybe technology week or auto week. Heck, even the Discovery Channel (and the awesome Late Late Show with Craig Ferguson) celebrate Shark Week.

But now we inaugurate the first ever (to our knowledge) Air Purification Week!

That's right - one week, three posts, all devoted to some of the greenest, most eco-friendly air purifiers on the market.

And why should you care about air purification? Well perhaps because metaphorically, the air we breathe in our homes could be comparable to the dirty fish tank scene from Finding Nemo!

Put another way, indoor air pollution is a big problem. For a comprehensive look at the issue, check out The Inside Story: A Guide to Indoor Air Pollution from the Consumer Product Safety Commission and the Environmental Protection Agency.

Here's one excerpt from the guide's introduction -

In the last several years, a growing body of scientific evidence has indicated that the air within homes and other buildings can be more seriously polluted than the outdoor air in even the largest and most industrialized cities. Other research indicates that people spend approximately 90 percent of their time indoors. Thus, for many people, the risks to health may be greater due to exposure to air pollution indoors than outdoors.

The guide has many suggestions for ways to improve air quality. Some of the suggestions involve better ventilation or allergen-proof mattresses. But the guide also discusses the virtues of air cleaners, while also emphasizing the importance of 'source control'. (In other words, if you have moldy carpets, get rid of them.)

Which brings us to our round up of some of the most eco-friendly and energy-efficient air purifiers on the market. Thanks in advance to all three companies for giving us a chance to test their products.

We start with the Sharp Air Purifier KC-C150U.

Sharp says that unit uses a triple filtration system consisting of -

1) A permanent washable pre-filter that traps dust and other large airborne particles

2) A washable active carbon filter to absorb odors

3) A true HEPA filter with an antimicrobial coating to trap 99.97 percent of particles as small as 0.3 microns. The HEPA filter should catch pollen, smoke, dust, dust mites, dander and mold spores.

Now the KC-C150U is a little pricey (MSRP $499.99), but it's worth noting that Sharp says maintenance costs should be low since the active carbon and True HEPA filters should last 5 years before replacement in average conditions. (Some other air purifiers require yearly filter replacement, which can quickly run into serious money.)

Sharp has also incorporated a proprietary air cleaning method called Plasmacluster ion technology into the KC-C150U. According to Sharp, Plasmacluster is "the leading air purification technology in Japan". What's more, the technology has supposedly been refined to the point that it is now on its 5th generation and therefore twice as efficient as the previous generation of the technology.

Just what is Plasmacluster technology? Here's how Sharp describes it -

Plasmacluster Technology splits water molecules into positively and negatively charged ions which spread through the room, surrounding airborne particles. This system effectively treats the air the way nature cleans the environment, just after a thunderstorm or near waterfalls, to help keep the air healthier and cleaner smelling.

To make it easier for the Plasmacluster to work as intended, Sharp has also incorporated a humidifier into the air purifier. So if you live in a desert environment or just need a bit of extra humidification in the dry winter months, the KC-C150U could solve two problems at once.

(Note that the humidifier has its own filter, which the KC-C150U manual indicates should be replaced every two years.)

So far so good, but what makes the KC-C150U a good Green choice?

Sharp says that the KC-C150U is 35 percent more energy efficient than standard models -- good enough to win an ENERGY STAR rating.

Thanks to our Kill A Watt EZ Electricity Meter (available from Current Energy), we can actually test these claims. Based on our tests, here is the sort of electricity consumption you can expect from the KC-C150U (with humidifier off) measured in watts.

On Maximum power - 75 watts
On Medium power - 14 watts
On Low power - 5 watts (!)

Note that using the Plasmacluster function (which can be turned on or off) didn't seem to affect energy usage much, although switching off the lights on the front of the unit did seem to save 1-2 watts.

I tend to leave the KC-C150U on auto, which seems use the low fan speed, but just a smidgen more power (7 watts). The auto setting really does seem able to detect whether it needs to ramp up the fan. One evening when a neighbor in an apartment down the hall was smoking, I used the KC-C150U to erase the smoke smell from my home. The unit worked on medium power until the smoke particles were trapped and then lowered itself to minimum power once the smell was gone.

Does it work as directed? Yes, the KC-C150U does seem to do a good job at trapping both particles and odors. It's easy to tell that the KC-C150U traps dust because the outer filter gets dusty fairly quickly, at which point you just snap it off and vacuum or rinse off the dust.

We were very impressed with the unit's quiet operation, which Sharp calls Library Quiet (TM) and compares to rustling leaves. We're not sure the unit sounds quite as nice as rustling leaves, but the KC-C150U does provide a soothing sort of white noise to have in the background when operating on the lowest power setting.

Things we're not crazy about -

1) The KC-C150U is made in China and feels/looks a bit plasticky. The design (particularly the integration of the humidifier) is very clever, but we still would have liked to see slightly higher quality materials for the nearly $500 MSRP.

2) Wheels! Another air purifier we tested had a set of wheels on the bottom. This wouldn't cost Sharp very much to add on the design and makes it ten times easier to shift the purifier around your apartment or house as needed.

Overall, we think the KC-C150U is certain
ly an excellent choice if you need a humidifier and an air purifier. After all, it's certainly eco-friendly to combine two separate machines into a single energy-efficient device.

Maintaining the humidifier (per the manual) and keeping it clean takes a bit of extra work, so if you already live in a humid environment, you may want to opt for a different purifier. Basic Sharp models can be much more cost-effective. If you don't need the Plasmacluster technology, for example, you could get the FP-P35CX - which still has a True HEPA filter - for just $229.99 (MSRP).

Where to buy:

You can purchase the Sharp KC-C150U for $499.99 directly from Sharp or at resellers such as Newegg.com (which offers the discount price of just $379.99). Abt.com also has the KC-C150U for $379.

The Sharp KC-C100U offers the same features for smaller spaces (254 square feet vs 347 square feet for the KC-C150U) and costs a bit less - $399.99 directly through Sharp or just $329.90 through Amazon.com.