4 ms·
This happened because of a confluence of several different factors at once: 1. Wildfires that threaten neighborhoods are not particularly common in Hawaii, so
by caesil 3y ago
This happened because of a confluence of several different factors at once:
1. Wildfires that threaten neighborhoods are not particularly common in Hawaii, so people don't have the same level of awareness around defensible space and fire protection, and the government doesn't educate about it / require it
2. Nonnative grasses have taken over swaths of Maui, and they burn more easily than native grasses
3. Maui is currently having a drought and exceptionally dry
4. A hurricane several hundred miles to the south caused very unusual wind conditions: VERY strong winds blowing from the opposite direction wind usually blows
5. The power company's lines are not capable of withstanding the gusts, and they did not shut down the power as a precaution, as happens in other wildfire-prone areas
So powerlines blew over, sparks ignited the grass, fire raced through the town.
- caesil 3y agoThe drought and hurricane are likely climate change related. So if climate change is causing outlier weather that can induce wildfires to become more common near you, you should start preparing before the government makes you. That's the takeaway.
- ipqk 3y agoClimate change should be number 1 on this list, and it not being listed is unconscionable. It's absolutely because of climate change. Everything else is secondary.
- caesil 3y agoI trusted that people could piece together that climate change is the upstream factor behind both the hurricane and drought. Sorry you think I don't have a conscience.
- amluto 3y ago#5 bothers me. There is no technical reason that a downed power line should start a fire. As far as I know, a certain amount of energy will be more or less unavoidably discharged when a power line hits the ground: the power line has some capacitance to ground, and it has a voltage (which varies with time) relative to ground, and the stored energy (1/2 C V^2) isn’t going to just disappear. This isn’t all that much energy. But there is no real reason that the power station needs to keep delivering more power to an arc after the capacitance discharges. Avoiding it is somewhat complicated, but the technology is available off the shelf: http://www.swedishneutral.se/main.php?name=gfn http://www.swedishneutral.se/main.php?name=gfn IIRC some Australian customers have tested this system by intentionally dropping a live power line onto dry grass, and nothing catches fire!
- notatoad 3y agonot necessarily to the ground, a power line going down could short with any number of structures, or other power lines. i've seen a grass fire start when a bird touched its wingtips to two lines on the same pole, and the smoking carcass hitting the ground was enough to ignite it.
- amluto 3y agoA short to a structure is likely to be a ground fault, and it will trip an RCD, and the arc current and energy can be controlled. A short to another phase wire can happen, but it’s less common.