What tactics should be used at fires with PV present?
How do I secure utilities on a PV system?
If you are not able to answer these questions, then hopefully this post can give you the sources to gain the knowledge to this modern fire ground hazard.
Photovoltaic (PV) is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect.
The U.S. solar market had its second largest quarter in history. The industry installed 832 megawatts (MW) of photovoltaic (PV) capacity, up 15% over deployment levels in Q1 2013. The utility PV market drove much of the growth in Q2 2013 with over 450 MW of projects commissioned in the quarter. The overall solar electric market remains on pace for another record year, with 4,400 MW of PV and over 900 MW of concentrating solar power (CSP) projected to come online in 2013.
This growth increases the potential of your fire department responding to a building with PV, irrespective of the PV being involved with the initiation of the fire event.
3 basic types of PV:
Free Training Videos:
Free Online Module:
Every Incident Commander, Company Officer and firefighter will greatly enhance their safety by taking this online class. UL has developed an online interactive training module. The program includes a professionally narrated description of all of the experiments, their results and the tactical considerations. Experimental video is used and graphical data is explained in a way that brings science to the street level firefighter. (Click on photo for module)
The Effect of Reflected Sunlight from Low-e and other Double Paned Window Glass on Vinyl Siding:
Glass in double paned windows may on occasion slightly warp or deflect due to a difference in barometric pressure between the interior of the glass panes and the outside air pressure. This can create a concavity in the glass. Such a concavity is a normal response to pressure differences, does not affect the performance of the window, and does not constitute a defective window condition. However,the concavity may focus sunlight reflected from the window in a fashion similar to the effect seen when light passes through a magnifying glass. The heat generated by the focused reflected sunlight has proven sufficient to visibly damage and distort vinyl siding on nearby houses. Any double paned window may cause this effect, but double paned low-e windows have a higher reflectivity quotient which can exacerbate the reflected light/vinyl distortion phenomenon.
The Vinyl Siding Institute (VSI) states that temperature ranges beginning at 160-165 degrees Fahrenheit can soften normal grades of vinyl siding. Darker colors absorb more heat, and will soften before lighter colors of siding. Heat generated from double paned low-e window reflected sunlight has been measured in excess of 200 degrees Fahrenheit, more than sufficient to soften and distort any normal grade or color of vinyl siding. There have been some reports of reflected sunlight damage to materials other than vinyl siding. Occasional wood discoloration and charring, and damage to paint and other plastics (e.g.,decking, window lineals, trim), have all been reported.
REFLECTED SUNLIGHT EFFECT
The use of double paned low-e windows will not necessarily result in any damaging reflected sunlight incident. A combination of contributing factors must be present before the effect occurs or causes damage to any nearby materials, including vinyl siding. The presence of the concavity in the double glass panes (resulting in the magnifying glass effect with a focused light beam) appears to be the primary cause of the heat generation, more so than the mere increased reflectivity of the low-e window. The angle of the sun is also a factor. A low angle of sunlight (such as might occur in late fall, winter, or early spring) is more likely to produce the effect. Other factors, such as proximity to the adjoining house, wind speed, air temperature, and the presence of buffering foliage are all said to have an impact on whether a damaging reflected sunlight effect does in fact occur.
Vinyl siding and insulating windows both have very large market penetration. Vinyl siding has been the most used siding product on new single-family homes in the U.S. every year since 1994. It was applied to 35% of all new homes built during that time frame. The majority of new vinylsided homes are in the south (40%), midwest (35%), and northeast (19%) (U.S. Census Bureau 2009). Based on sales data and projections from 1999 to 2019, approximately 45% of residential vinyl siding is, or will be, used in the new construction market; the remainder will be used for retrofits and repairs (Freedonia Group, Inc. 2009).
The U.S. Department of Energy and model energy codes have made improved residential energy efficiency a national priority. Therefore, standards have called for increasingly stringent energy efficiency requirements for windows. The performance levels achieved by insulating windows are mandated by nearly all local building energy codes for both new construction and replacement in existing buildings. Windows are typically designed to meet the requirements of the International Energy Conservation Code (IECC), the most commonly adopted model energy code in the U.S. for residential buildings. To meet IECC’s U-factor and solar heat gain coefficient (SHGC) requirements insulating double-pane windows with low-emissivity (low-e) coatings are often used.
WEBSTER GROVES • Firefighters quickly extinguished a fire Saturday on the roof of Webster Groves High School, officials said.
The fire broke out about 1:45 p.m. The cause has not yet been determined, but Webster Groves Battalion Chief Tom Yohe said it was “possible” the fire was sparked by one of the school’s solar panels.
Departments from around the area responded to the 2nd alarm call. The fire was contained within 15 minutes, Yohe said.
Officials said there may be some water damage to the school’s third-floor classrooms from fighting the fire. No firefighters were hurt, and any damage to the building was minor.
The school’s seniors graduated Friday, but Yohe said because access to the roof was difficult he “seriously doubted” the fire could have been started by students. The school is expected to be open Monday.