Residential - Electricity
The iconic photovoltaic (PV) panel is arguably the most recognizable symbol of renewable energy worldwide. Photovoltaic panels work by turning the energy of sunlight into DC electricity through a process known as the photoelectric effect Photoelectric Effect
The photoelectric effect is the observation that many metals emit electrons when light shines upon them. Electrons emitted in this manner can be called photoelectrons..
Each PV panel is made up of a multitude of smaller PV cells, combining their individual small electric outputs into a larger output on each panel. The electric output of each panel is then combined with the outputs of the other PV panels to produce a large system-wide output.
The number of panels used will depend on a number of factors, such as available roof space and size of grid connection to the house. These factors often result in a system with four to sixteen panels. Each panel measures about 3’ by 6’, which translates into a roof area range between 75 sq. ft. and 300 sq. ft.
The racking system is the structure on which the PV panels are mounted. For residential installations, the racking system typically consists of multiple rows of footings and rails that get structurally mounted to the roof of the home.
The footings are used to mount the rails to the roof. Each footing is structurally mounted to the roof rafters with a 4" lag bolt, and incorporates a flashing plate that slides under the roof's shingles to provide a weather-tight seal around the penetration.
The rails are bolted to the footings, and provide the structural base upon which the PV panels are mounted. For safety purposes, each rail is electrically grounded to mitigate lighting strike and short circuiting hazards.
A string inverter is a device that takes a high voltage DC output of an entire PV array and turns it into 240V AC power (the same as the power used in your home).
- Lower up-front cost compared to micro-inverters
- Output less power than an equivalent system using micro-inverters
- Less reliable, since a problem anywhere in the system propagates through the entire system
- Can't monitor the output or status of individual PV panels, only the entire system output
- Can't add additional panels in the future. Removing existing panels affects performance of remaining panels.
A microinverter is a small device designed to turn the DC power produced by an individual PV panel into usable AC power. In other words, a ten panel system would have ten microinverters. Each microinverter detects how much DC power that a particular panel is producing, allowing it to draw the optimum amount of electric current from that panel through a process known as maximum power-point tracking.
- Allows the PV array to output the maximum possible power, regardless of shading on or problems with individual panels
- More reliable since any fault within the system remains isolated from the rest of the system, allowing it to keep running
- Each PV panel's output can be monitored independently, making maintenance extremely easy to manage
The line run is the part of the system that brings the electricity from the roof into your home's electrical breaker panel.
The line run consists of a cable that gets installed either inside or outside your home. The cable itself features several layers of protection including an inner electrical insulator, steel shielding, and an external waterproof membrane.
For safety reasons, the cable is connected to an electrical disconnect box before being wired into your home's electrical circuit-breaker panel.
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We've been installing solar panels in Nova Scotia for decades, so we know a thing or two about how to get the job done. As the primary installation company under the Halifax Solar City program, we have been installing literally hundreds of solar systems each year. We are fully certified through the Nova Scotia Construction Safety Association, and take pride in providing a full solar system solution to homeowners; from permitting and design, to installation and maintenance.
Monitor your system in real time
With Doctor Solar's standard micro-inverter monitoring system, you can see exactly how well your photovoltaic array is performing in real time. Because each PV panel has its own dedicated inverter, you can see excatly how much power each panel in your array is producing! Just log in to your monitoring system web page for useful insights into your solar system, including how much money you've made. Best of all, your system will automatically email Doctor Solar if there are any problems with your system!