Pretty much! We're pleased to announce that our flagship Luggable XL Ultra and Triple Exhalaron now officially carry EnergyStar certification (listed under brand Rainbow).
And ... the XL Ultra with Filtrete MPR1900 (MERV13) achieved a gobsmacking Energy Efficiency of 26.2 cfm (cubic feet/minute)/Watt. That's a full 2.42 x higher efficiency than the next most efficient large purifier (10.8cfm/Watt Carrier RMAP-SST) in the entire EnergyStar database! And 9 x higher energy efficiency than the 2.9cfm/Watt purifiers that eek past the EnergyStar specs at the low end! An XL Ultra running at full 402 cfm DUST CADR (clean air delivery rate) for a whole year uses only 81 kWh of power, compared to 650 kWh for its least efficient peers of similar CADR.
Our smaller Exhalaron Ultra Tri achieved an Energy Efficiency factor of 16.2 cfm/Watt and 42 kWh annual consumption, well outperforming the next most efficient small purifier (a Blueair with 13.8 cfm/Watt).
But how?
You're probably wondering how this is even possible. Is it a trick? We basically utilize extra filter area for more efficient low-pressure operating points, but several factors contribute:
● As UC Davis Dean Richard Corsi originally foresaw, more moderate filter grades like MERV13 (MPR1900) and HEPA H10/H11 capture more particles faster than the stringent HEPA H13, even as some particles escape on the first pass.
● We also want to thank PC gamers. Three decades of intense competitive pressure have honed the pricing, efficiency and quietness of leading PC fans way beyond other classes of fans.
● Due to certification expense, most HEPA manufacturers only test their top fan speed. They choose a high RPM for their top fan speed to reach competitive CADR (capture rate) through stringent HEPA H13. Top speeds then have a piercing whine while the high pressure expends more energy per captured particle. HEPA efficiency factors are quite a bit better at their quieter low-moderate speeds, but their CADR also drops by 1/2 or more vs. what the product advertises (at top speed).
Only PC fan purifiers are proven to deliver high particulate capture rates like 400cfm while being supremely energy efficient and quiet. The doubled filter area does not just enhance energy efficiency -- it also doubles the lifetime between filter changes as the dust load spreads across more media. And since we use common furnace filters, the doubled filter media does not cost you more. (Bonus convenience: you can purchase the non-proprietary filters at multiple online and in-person stores.)
Marketing gimmicks and double invisibility
We maintain that the standard use of stringent HEPA H13 in room purifiers is a purity marketing gimmick of little practical value, as highly purified air from the blowers dilutes into dirty room air within inches of most outlets. Indeed, switching to PC fan purifiers offers equivalent energy savings as the switch from incandescent to White LED light bulbs a few years ago.
Ironically, the Trump EPA threatens to shutter the EnergyStar program this fall. At one level, the $5,000 certification cost per model is a large expense for a small manufacturer like us who wants to stay on top of the best PC fan models, filter media and design. And some might say that the EnergyStar program failed to spur industry creativity to find these more efficient operating points decades ago, instead of leaving them to be surfaced by a DIY community. But having standard AHAM/EnergyStar benchmarks in place gives our small company the opportunity to verifiably highlight a substantial efficiency breakthrough. In other words–these certifications give us credibility in an industry where trust is important. We knew back in 2022 that this way of making air purifiers was a game changer, but certifications mean you don’t have to take our word for it.
Room purifier performance is doubly invisible -- consumers can't easily see the electricity consumption or their air becoming cleaner. This double invisibility invites marketing scams without some form of enforced, standardized industry testing. If you can afford your own ammeter and particle counter, we strongly encourage you to try some tests of your own to help your intuition with how quickly these devices can clear your rooms.
Gratitude
We want to thank Dean Richard Corsi, Jim Rosenthal and the Twitter DIY community who eagerly forged alternatives to retail HEPAs at the peak of the COVID pandemic in a unique quest for safer classrooms. We also want to thank our fan and filter suppliers CoolerMaster and Filtrete, whose superlative components really put these results over the top!
