There are so many questions that customers have when making the decision to invest in a solar PV system. We’ve put together a list of some frequently asked questions that we get from our customers that we have found really helpful to our customers and prospects.
How long does the photovoltaic (PV) module last?
PV modules last a long, long time. In decades-long tests, the fully developed technology of single and polycrystalline modules has shown to degrade at fairly steady rates of 0.25%-0.5% per year. Our solar panels/modules come with a 25-year power output warranty (reflecting the manufacturers’ faith in the durability of these products) and are expected to last at least twice that long. The power output warranty on the solar panels/modules is provided by the manufacturer of the panels/modules and states that at the end of the 25th year, the solar panels will still produce a minimum of 80% of their original power output. However, keep in mind that PV modules are seeing only six to eight hours of active use per day, so we may find that life spans of 40-50 years are normal.
What about reliability and maintenance on the system?
Reliability: Solar electric systems are a proven technology and are extremely reliable. PV cells were originally developed for use in space, where repair is extremely expensive, if not impossible. Most manufacturers guarantee that their solar modules will produce 80% of their initial production rating after 25 years.
Maintenance: Once installed, the solar electric system requires little or no maintenance (especially when storage batteries are not used) and will provide electricity cleanly and quietly for 25-plus years.
How strong are the panels/modules?
The panels/modules are Underwriters Laboratories Inc. (UL) certified and tested to withstand hail, hurricane force winds and rainstorms.
What is the maintenance on the PV panels/modules?
Because PV modules have no moving parts, they are virtually maintenance free.
How will the weather affect the solar electric system?
Solar electric systems are designed to withstand all weather conditions. Lightning, wind up to 120 miles per hour, and extreme temperatures are all things the solar system can handle. However, these conditions may temporarily reduce energy production.
How does a solar electric system store electricity after the sun goes down?
The most basic solar energy system is what is known as a “Grid-Tie Only” system. There are no storage batteries. Excess electricity produced by the solar panels/modules will be directed back to the local utility grid. You will receive credit for any power that you “sell” to the utility company. This is what is known as Net Metering.
What is Net Metering?
Policies for net metering vary from state to state. Solar net metering allows electric customers who generate their own electricity using solar energy to bank excess electricity on the grid, usually in the form of kilowatt-hour (kWh) credits. These credits are used to offset electricity consumed by the customer at a different time during the same billing period (i.e., when a facility’s solar energy system is not generating enough electricity to meet the facility’s needs). In effect, the customer uses excess generation credits to offset electricity that would otherwise have to be purchased at the utility’s full retail rate. Net metering is accomplished by installing a bi-directional meter.
Does the solar system produce electricity on a cloudy day?
Yes, a solar panel does produce electricity even when it is not placed in bright sunlight. On a normal cloudy day, there is always enough solar irradiance, by which the panel will produce electricity.
What happens when I need to re-roof?
The solar project developer is aligned with roofing experts, and will not install solar without complete assurance that it is in the best interest of the property. Developer will protect the warranty when installing on newer roofs. NOTE: A roof inspection is conducted to ensure the roof is in good condition prior to installation.