Our Solar Expert Answers Your Questions on Solar Panel System Costs – Part II

This blog is a part of an interview series where we sat down with our solar expert to get your burning questions answered. Visit this link to read Part 1.

Now that we know about the initial installation costs from Part 1, we asked our solar expert about any ancillary costs related to installing a home solar system. Here’s what we learned about some pre and post-installation costs you should be aware of:


Q: My roof is over 15 years old. Should I reroof it before installing solar panels?

A: One of the most common home upgrades before solar installation is roof repair. As previously mentioned, solar panels are expected to last 25 years, while most roofs are rated for 20 to 50 years, depending on materials. If your roof is already 15+ years old, depending on its condition, your installer may recommend either reroofing partially or entirely before installing solar panels. If roof repair or replacement is required after solar panels are installed, the solar system will need to be fully removed and reinstalled, which will cost more than fixing it first.


Q: Is it necessary for me to upgrade my electrical panel?

A: Another common upgrade is the electrical panel, especially if you’re living in an older house. The National Electrical Code says that an electrical panel can have up to 120% of its busbar rating as power sources, including the utility, solar, and batteries. The busbar is the metal connection point for all circuit breakers in the electrical panel, used to distribute power to each circuit breaker.

Suppose your home has a 200-amp main electrical panel with a 200-amp busbar. In this case, the rule allows an additional 20%, or up to 240 amps of total power input into the panel. 200 amps are from the utility, which leaves space for a 40 amp-rated solar system (equivalent to an 8 kW system). Home battery storage systems are also affected by the 120% generation and energy source busbar rule. If your solar panel system includes a 30-amp battery, 200-amp busbar isn’t enough.

Many modern electrical panels are considered “solar-ready” due to their heavier-duty busbars. For example, the Energy Center includes a 225 amp-rated busbar, which can support up to 270 amps of input to the house (225A × 120%). So, including 200 amps from the utility and 40 amps from solar, there is still space for a 30 amp home battery. Another way to resolve the 120% rule is to use the Schneider Backup Control Switch, allowing a supply-side connection (available in the USA and Puerto Rico).

Older homes may even have 100-amp electrical panels with 100-amp busbars. In this case, upgrading the electrical panel is to be expected when going solar.


Q: Will there be a need for post-installation maintenance?

A: Solar panel systems don’t require much maintenance. However, periodic cleaning of your solar panels will improve solar power production, especially if you live in a dry or dusty climate like southern California. As working on roofs can be dangerous, we recommend hiring a professional solar panel cleaner for this; they typically charge per panel for this service. If you live in a rainy region, such as the Pacific Northwest, regular rain may reduce the need for cleaning.

If there are trees around your solar system, it is important to clear away leaves and other organic debris around or below the solar panels on a regular basis, as these materials can cause premature wear on roofs.


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