Venting Homes With Rooftop Solar Panels

[bigfitz2004 19]

With the cost of energy rising, more residential homes are instalingl solar panels. I found one house in our fire district that has several solar panels installed on a small roof. My question is, how do you vent a roof with these solar panels on a residential home?

I checked old topics on EMTBravo, this topic was never discussed.

[ajsbear 11]

Not only venting the roof but just the extra weight on the roof worries me.

[Guest]

The solar panels would only be a problem for venting if the fire was directly underneath. I know of a few houses that have them and they are not terribly large that I've seen, but thats not to say your's aren't. I would be more worried about them should a collpase occur, these would be considered Live loads I assume?

[x242Steve 1]

One of our members, who is also a veteran electrician and building inspector, actually brought this up the other night.

Aside from the weight and access issues, he noted that during daylight hours these panels always have electricity flowing through them. Electrical code requires that there be a shut-off to kill the flow going into the house, but due to the inherent properties of solar panels, the only way to totally kill the power at the roof is to take away the sunlight. In the City of Rye, building codes do not allow solar panels to be on the side of the roof that faces the street, so you might not even know that the house has solar panels on the back. One of our other members suggested that addresses with solar panels should be noted in the CAD system, that way during a confirmed fire the IC could be notified (Yes we should always be doing a size-up walk-around, but the homeowner is likely to want the solar panels positioned in the least-visible spot)

Edit: I realize the initial question was "How do you vent a roof with these solar panels on a residential home?" Without being sarcastic I would say "Carefully." (Although as ALSfirefighter teaches, you should be being cautious/careful already!) Hopefully the panels will not prevent access to the area adjacent to the peak of the roof where you will usually get the most effective vertical ventilation.

Edited November 28, 2007 by 242steve

[firemoose827 324]

Excellent question, and I hope more members will answer with more info. We do not have any in our district but with time I am sure will eventually. I never would have guessed there was juice running through them at all times and that there was a shuttoff on them somewhere. Where is the shuttoff located?

My guess would be the same as far as venting is concerned, vent on the opposite side of the roof as the panels and watch for the added load on the roof to cause more of a collapse issue.

Good Topic and hopefully there will be more discussion on this.

Moose

[hudson144 150]

It is a good subject and along with procedures for venting maybe one of you ''WIRE NUTS'' (electricians) can educate us a little on the hazards of these units to include shut off procedures,how much if any "juice" may be stored in the units.

[johnvv 20]

FYI-

Solar Panels produce DC current (at a lower voltage). The DC voltage then inverted from DC to AC either by means of an inverter, or by charging batteries that run a generator. In Westchester County, a disconnect means for a solar system that back powers electricity to the utility company has a disconnect located by the house meter. The equipment needed for the solar panels is usually located by the main service panel in the home.

Hope this helps-

A wire Twister

[Guest bibbles10504]

Excellent question, and I hope more members will answer with more info. We do not have any in our district but with time I am sure will eventually. I never would have guessed there was juice running through them at all times and that there was a shuttoff on them somewhere. Where is the shuttoff located?

Good topic.

There is a shut off to them. Solar panels take sunlight and convert that to a DC current, once it is in that form it needs to be converted to AC current so you can use in your house. There is usually a converter near them. A lot of times I've seen them in the attic. The on/off switch is usually located on the converter. I've also seen some where they run directly to a "battery bank" where the energy is stored and then converted to AC power at night when the solar cells arn't working.

The panels themselves are fairly inefficient so one panel does not create that much power, the problem is when you get a lot of panels together and the electricity is combined. I would assume though that if you break them somewhere in the center it would break the membrane and stop the electricity from being made. And you should be ok as long as you don't come in contact with both the end of the panel where the wires are attached. But i'm not totally sure about that.

Edited November 28, 2007 by bibbles10504

[hudson144 150]

What differences might we see between commercial/residential units???

[Goose 188]

Good friend of mine used to live in a house with solar panels which experienced a fire that gutted the entire top floor of the home while he was living there. This occurred roughly 8 years ago, but to the best of my recollection the side of the roof w/ the panels was avoided entirely. One or two holes were cut in the roof on the opposite peek.

[ny10570 745]

There are two types of solar panel. Electric and fluid. In residential, I'm 99% sure you'd only see water but in larger commercial applications you could be looking at and oil based heat exchanger.