How do I keep my solar system running well?
In my last post, I answered a question I often hear from solar system owners - "Is my solar system working?" In this post, I'd like to discuss ways to keep your investment reliably delivering those valuable financial and environmental benefits. Specifically: "How do I keep my solar system running well?"
The best way to ensure your system keeps producing is to monitor the output. Statistics show that a monitored system produces more than an un-monitored one simply due to quick failure recognition. Virtually all solar electric systems can be outfitted with a remote electronic monitoring system. As described in my previous post, most inverters come with a proprietary, reasonably priced monitor that will alert you if your system under produces or trips offline. If you don't already have one, your solar company can install a monitor which generally cost under $1,000 for a standard residential project.
This assumes you have a stable internet connection for the monitor to upload the information to its user interface portal. Note that more sophisticated devices can also monitor your home's consumption along with your solar production which allows you to easily assess your 'net' energy consumption from the grid.
In the beginning, many people were told that solar was 'maintenance free'. While solar is incredibly reliable, simple preventative maintenance is vital to keep your system operating optimally. While we do not recommend homeowners get on their roofs, many systems can be visually inspected from the safety of ground level. If you spot a problem, ask your installer or a solar service company like HelioPower to fix it.
First, visually scan each and every solar panel. Look for broken glass (from golf balls, rocks thrown by the neighbor kid, rare panel failures, etc) which will be obvious. Since solar modules are made with tempered safety glass, a broken panel will look completely shattered. Next, look under the panels for loose and hanging wires. Any wires laying on the roof surface should be secured back up under the solar array. Hanging wires move with the wind and over time, can damage the roof, cause the wire insulation to be abraded and shut down the system with a ground fault.
While you are looking at the array, check to see if any tree branches or other vegetation are creating shade on the panels. While some types of inverters do a better job at accounting for shaded panels, anything blocking your solar panels from direct sunlight should be removed. We recommend full, unobstructed sunlight on the array between 9am-3pm at a minimum.
Next, check to see if the panels are clean. Dirt is like shade on your panels and production is reduced commensurate with the amount of dirt covering the cells. If dirt is blocking 10% of the solar irradiance, then you are losing 10% of your production. As a general rule, we like to clean residential solar arrays once per year in early summer to prepare for energy harvest season. No need to obsess about it, however. A thin film of residue on your array is fine, but a thick layer should be removed. In many climates, rain is enough to keep modules clean on a sloped roof.
Finally, check your wall mounted string inverter. It should be in a shaded location without any vegetation or household items blocking airflow. If your unit comes with fans, it may have a filter grill that should be removed and washed or blown out with air and replaced. Remember to keep your inverter in the shade and your panels in the Sun!
Keeping your solar monitored, clean and unshaded is a great way to ensure a highly productive and reliable renewable energy system for years to come.