A solarized roof system can help save money besides helping save the environment.
This is even fostering an upsurge in localized community-college green-jobs certificate programs.
In fact, according to the U.S. Department of Energy, 2013 was a record-breaking year for the solar power industry. The addition of 23,682 workers brings the total to 142,698 Americans employed in the solar industry.
While the figure is paltry compared to the number of unemployed, the number of solar installations will likely sky rocket due to climate change. Imagine the snowball effect of having less available hydroelectric power due to drought and divestment in dams.
Conserve Energy Future explains why solar energy is natural, clean energy. By reducing one's carbon footprint in half, one is helping reduce greenhouse gases, such as carbon dioxide pollution, while also hopefully saving on the utility bills.
A key question for initial consideration is "Do I have the space for it?"
Here is a short list of considerations for ordering or installing flat panel solar photovoltaic (PV) modular arrays: (Refer to the photos)
- Roof condition/structure. What is the condition of your roof? Do you already have a green roof where mixed purposes won't work (eg. water collection vs. solar panels). Can the roof support extra weight?
- Roof material. Certain roof materials can create obstacles for solar panel installations. These include: traditional tile, wooden shakes, thatched, rough cut stone, recycled rubber, copper
- Roof direction (shading) (rain shadow). Consult the solar radiation map or solar insolation chart for your area. Note that the data doesn't include the effects of local shade trees, building cover, or other possible reductions affecting efficient energy collection.
- Solar Photovoltaic (PV) Modules are flat plates packed full of (poly) crystalline silicon cells which conduct electricity when their electrons are excited by sunlight. For estimating the number of panels needed, figure that each panel generates 200 Watts apiece. (1 Kilowatt=1000 Watts)
- Number of Panels: For instance, the 4 KW-hour solar system, which would cover most small appliances, would require about 20 panels. This is obtained by dividing 4000 Watts by 200 Watts per panel. The formula: (4 KW x 1000 W/KW)/200 Watt/panel= 20 panels.
- Panel dimensions are approximately 40" wide by 60" long and generally weigh between 45-52 pounds. Smaller sized panels are easier to lift whenever necessary. For estimating the space required on the roof, 3.33 ft wide by 5 ft long= 17 square feet apiece.
- Measure the roof space needed on asbuilt plan drawings. The roof slope should be included in the area calculation. For instance, divide the horizontal length shown on the plan drawing by the cosine of the roof pitch angle to obtain the total slope length. (Check your measurements by climbing on the roof or taking floor measurements inside).
- Example: For a 4 KW solar system with 20 panels, the roof space required would be: 20 panels x 17 square feet/panel= 340 sf. However exactly where the panels will fit will vary according to roof type. They may fit along the south side of a gable roof, or have to be divided among portions of a dormer roof.
- Other options of course are available, such as ground mounted solar panel systems. In fact, these may be more flexible with regard to accessibility and maintenance, particularly if you intend to add-on slowly, build it yourself, or go off-grid with a back-up battery system.
This list of considerations is by no means conclusive, but it can guide you in the decision-making and consultation process of a significant energy-saving investment.
Although there are certainly challenges to solar PV array installs, such as comparing sales contracts and submitting designs to techno-regulatory agencies, there are quite a number of free, helpful, informational resources, some of which are included below.
Links to Resources: