Thursday, January 27, 2011

Photovoltaic Avalanche!

For my local readers, you know exactly how much snow we've been getting this month - record breaking historic snowfalls in fact!  For my long-distance readers, we've had snowfalls leaving us with 29 inches of snow, 18 inches of snow, and lots of smaller amounts sprinkled in.  It's one of those winters we'll always remember as the one where we had snowstorms every week, and where the kids only had a few full days of school the entire month.  My composter is buried somewhere under all that white stuff.  There's no where left to put the snow, the piles are so high. While I know it is difficult for most of us, and lots of people are grumpy over this, I'm smiling a little inside for all the folks in the snow removal business.  I hope they make piles of money, and I hope one of them will use that money to buy Knowles Landing! (hint hint)  See, I'm such an optimist :)

With a new solar array on our roof, we were a little nervous riding out that first big storm which dumped almost 2 1/2 feet of snow on our solar panels.  I had visions of the southern roof collapsing on my children's bedrooms.  It felt like a long night.  Neighbors even asked how our roof was holding up which only made me more nervous.  No worries though...once the clouds broke and the sun came out, the snow over the biggest portion of the array slid right off the roof and we were producing solar energy again.  Yes!

Apparently we weren't the only ones worried, because Sunlight Solar sent out a special winter edition newsletter discussing this exact topic!  They eased our concerns by reminding us that our array was designed specifically for our roof using their calculations based on our rafter and roof span measurements and potential additional weight of snow.  Concern #2 was about whether or not we're producing energy with the snow covering.  Their reassurance is that with net metering, which we do, we're looking at the overall energy produced annually, and with the days already getting longer, we shouldn't worry about a few days of snow cover.  They also don't recommend trying to remove the snow manually, as any damage to the photovoltaic panels will void the warranty.  Plus it could be dangerous.  Several feet of snow falling at you rather quickly and all.

After last night's huge storm our roof was covered in snow.  Out came the sun though, and around 10am, with a sound like a distant rumble of thunder, a HUGE avalanche of snow fell from my roof, going right past the window where I was sitting at the computer.  Startled, I yelped and heard my little one screaming with delight at the "waterfall of snow" she was witnessing from the window below me!  Sunlight Solar had explained that once a section of the array is uncovered, it doesn't take long for the rest to come off.  This is my roof around lunchtime today!



So, a new note to add to the "advice for people considering photovoltaics" is to remember that when all that snow falls off, whatever lies below WILL be buried and possibly broken (my poor scotch pine shrub broke into pieces after the 1st snowfall's avalanche.)  I would also remind the kids not to walk within a 6 ft radius of the edge of the foundation for fear of any snow falling on them.

The sun is setting for the day, but rest assured that even with only half of my roof uncovered we were still producing at 7.41kW the other day :)  

1 comment:

Mama Gone Green said...

Wow! Crazy snow. Figures that as soon as you get your panels on it starts, right? ;)