Tag Archives: wildfires

Fire and Smoke and Evacuations


Leaving heavy smoke in Tahoe on Wednesday 8/19

We headed back home on Wednesday, leaving the heavy smoke in Tahoe from the Loyalton Fire, through the smoke filling the Central Valley to reach the heavy smoke in the Santa Cruz Mountains from the CZU Lightning Complex fires.


Looking south and west from the house  (Wednesday evening, 8/19)

 
Ash and charred leaves deposited around the house (8/19)

As we came through Vacaville and Fairfield on I-80, we slipped through just before the LNU Lightning Complex fire jumped I-80 and even saw flames from the interstate:

 
LNU Lightning Complex Fire about to cross I-80 near Fairfield on 8/19

On Wednesday and Thursday we prepped for evacuation, loading up the cars with necessities and some irreplaceables, prepping the house as per wildfire pre-evacuation recommendations (moving furniture away from windows, etc).  Sure enough, the mandatory evacuation zones were expanded Thursday evening to include everything west of highway 17 (including downtown Scotts Valley).  We’re a little south of Scotts Valley and just east of highway 17, but we decided to go ahead and evacuate Thursday night – heading back to Tahoe.

The evacuation areas are expected to remain in effect for a few weeks.  Darlene will be renting a place near Stanford Hospital in Palo Alto as she’ll be returning to work next week.

So far, it looks like they’ve been able to mostly hold the fire west of highway 9 and north of Santa Cruz and Davenport.  Unfortunately, we’ve got the potential for more fire starts due to more dry thunderstorms expected around the Bay Area from Sunday (8/22) through Tuesday morning (8/24).

Here’s a combined, interactive map showing both the perimeter of the ZCU Lightning Complex fire and the evacuation area.  63,000 acres burned, 77,000 people evacuated – snapshot as of Saturday, 8/22:

Here’s a really nice mapping tool (CalTopo) that can overlay various satellite data (like VIIRS) on a map source of your choice and plot additional weather data like wind patterns.  You can even zoom in to see individual temperature sample numbers showing where the fire is hotter and cooler or no longer present:

For more info on the Santa Cruz Mountains fires, here’s some resources:

Update (Thursday, 8/27):  81,000 acres affected as of this morning but they’re continuing to get good control of the fires across the Santa Cruz Mountains.  As the mandatory evac area was never extended to where we are (just east of highway 17), Darlene headed back on Monday evening since she had to go into work at the hospital on Tuesday and I headed back with the cats on Wednesday evening as things seemed to be continuing to go well.  As of 3 pm Thursday, they’ve lifted the evacuation order on Scotts Valley and surrounding areas.

Share
Also tagged , , | 1 Comment

Fire and Smoke (and air filter test)

Lots of wildfires in California lately and over 100 in the Santa Cruz area this year so they’ve closed many of the county parks to try to reduce the risk.  This one a couple of weeks ago (the Rincon fire) was quite visible from my place but happily they were able to get it under control in a couple of days:

 

After seeing someone test the air filtration of Tesla’s Model X and its “biodefense mode” against the heavy smoke we’re getting from our wildfires this month, I decided to pick up an inexpensive air quality sensor to test my home’s air as well as my Model 3’s more mundane filtration system.  (The Model 3 doesn’t have the Model X’s fancy “biodefense mode” or huge HEPA filters.)

With the PM2.5 sensor reading 150 μg/m3 (unhealthy) in the San Jose area (due to smoke from the Camp Fire that burned through Paradise, CA), I found that the Tesla Model 3’s air filter would bring things down to the 20’s in the cabin in just a few minutes when recycle air was turned on.  Later, I stopped and made a video to record it falling from 135 to 5 μg/m3 in less than 10 minutes. It climbed back up to the 80’s pretty quickly though when I turned off recycle air and let it bring in fresh air:

This video was even picked up by Teslarati (“Model 3 protects owner…“) and re-tweeted by Elon.

Hi, Elon!  But they didn’t pick up on my follow-up test to compare the Tesla to a Toyota:

Comparison with Toyota RAV4 EV

I decided to repeat the test with my 2013 Toyota RAV4 EV.  This time the starting air quality wasn’t nearly as bad as my initial test but both the Tesla and the Toyota were able to filter the cabin down to a reading of zero from a start of 50 μg/m3 with recycle air turned on. At full fan speed, the RAV4 took about 10 minutes and the Model 3 was able to do it in about 3-4 minutes.

With recycle air turned off (fresh air intake on), the PM2.5 reading in both cars climbed up again. The Tesla was able to hold it around the low to mid 30’s but the RAV4 went up to essentially the outside reading of 50 μg/m3 again.  So the Model 3’s system does work better.

One other thing of note is that the RAV4 ended up with a much higher concentration of TVOC (total volatile organic compounds), even though the vehicle is five years old. Presumably this is off-gassing of some of the materials in the cabin.Oh, and I forgot to turn off A/C in the RAV4 for the test – hence the temperature drop.

Here’s more detail in screenshots – RAV4 start and finish with recycle on:

Image Image

Model 3 start and finish with recycle on:

Image Image

On a subsequent four-hour drive to Tahoe in the Model 3, I encountered much worse air along the way (San Jose, Central Valley, Sacramento, etc). I’d guess the PM2.5 count was easily at least 150 μg/m3 and probably much higher in places, but I avoided opening the windows to test it. I kept the air on recycle and saw that the particle count held down around 20 but sometimes climb to the 30’s. Not bad, given how bad it was outside.

Share
Also tagged , , , | Leave a comment