Clean Air Club, Solar Edition?

SuperHusband built us a Corsi-Rosenthal box the other week, which went quite well after I talked him off the ledge of compulsively re-engineering the thing.

“But it was designed by guys with PhDs in compulsively-re-engineering exactly this thing,” I said. “It’s too late. It’s already been optimized.” He probably had to make a few tweaks anyway, but it went so fast there couldn’t have been too many improvements, I don’t think.

Here’s a thread on how to make a version with a round fan, and here’s the YouTube video of that.

Airborne infections are not the only thing you might need to not have in your house. These notes on disaster-recovery from the recent wildfire in Colorado may be of interest to those who live in other wildfire zones. Read the whole thing, but here’s the key bit about CR Boxes:

• It’s very important to avoid models with technologies that generate unhealthy levels of ozone. These models, which sometimes falsely advertise odor removal and disinfection. include air cleaners that use ozonizers, ultraviolet radiation, or ionizers to remove VOCs.
• The California Air Resources Board has a certification program (without this certification, it is illegal to sell an air cleaner in California) and information on ozone generators to avoid.
• If you are on a budget, you can make an inexpensive air filter (aka, Corsi-Rosenthal box fan filter). This air filter was developed in response to COVID and is great for particles, but will not address gases/VOCs, which is what we smell.
  • Update: Odor Relief Carbon Air Filters can be used in this setup to remove particles and odors.
• Here is a great blog post from Dr. Shelly Miller about air filters/purifiers for the home.

Commercially-available air purifiers, IME, are generally more compact, don’t have soft and fluffy panels exposed, and have the advantage of being UL-listed.  (OTOH, they aren’t translucent, so choose your aesthetic.) Nice feature of CR Boxes is that the fan (and possibly the filters, depending) can be repurposed down the road if your air-purifying needs are temporary or you decide to invest in a commercially-made product. If you build the box with the fan blowing outward, while in use as an air-purifier it can also double as, surprise!, a fan.

Here’s another thing to know: You can run a box fan on a portable solar panel.

(This is a randomly chosen shopping link from Amazon for a product to illustrate the concept, I have no knowledge whatsoever of this product and don’t recommend it or not. Naturally if you’re a DIYer you die inside when you see these things, someone cue the house engineer to figure out a way to do it twice as well for half the cost.)

Here is a discussion of how smoke haze affects solar electricity production, including a discussion of the performance of different types of solar panels. Obviously if your sky is darkened by wildfire smoke, you’re going to see a drop in performance.

–> Also, I hope it’s *very* obvious, if you are jury-rigging a homemade filter box to a DIY’d solar panel, if there’s any doubt whatsoever about fire hazards, don’t run the thing unattended?

But, but, but . . . Yes, personally, if I lived in a sunny climate in a state known for both massive wildfires *and* an unstable electrical grid? I’d be exploring my options.