Even if the damage caused by the utility's equipment was an accident, fire victims have the constitutional right to seek compensation for it if they can show that Hawaiian Electric was functioning like a government agency.
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If I store a vat of acid in your garage, and it spills, should you have no recourse?

I think the key bit would be the test of "caused by the utility's equipment".

Did the vat of acid leak because, say, the vat was getting near its expected lifetime? The acid owner oughta pay.
Or was it because someone else set the garage on fire, causing the vat to get crushed when the roof fell in? No, the acid owner shouldn't pay.
If the proximate and/or underlying cause was something that no reasonable person would call plausibly foreseeable (rhino fell from transport plan onto garage?), then also probably not.

The grey zone is kind of like the ones faced by Tepco executives: was it a risk that might well be unlikely, but a reasonable person would have called foreseeable and entirely possible.
e.g., the acid vat was at the back of a garage being used regularly for parking. Everybody knows that once in ever 5000 times parking a car you'll bump the back of the garage, but the tank wasn't built to withstand that.
In this case, I'd hold the acid owner liable.

In the real world, of course, what makes sense might not matter much. Laws, contracts, luck, money...

Jim