As mentioned above, depending on where your home is located, or if you are looking for commercial solar insurance instead, the insurance carriers you talk to may have different policies about insuring solar panels.
If you have a farm, or other large property and have installed a large solar system on your property, your homeowners insurance companies may exclude coverage for larger scale residential projects where net metering is a large portion of the annual energy usage.
Some states, such as Florida, may also require carrying general liability insurance for solar panels to cover potential 3rd party claims due to electrical risks.
Before having solar panels installed on your house, be sure to ask your insurance broker to request a copy of the proof of general liability insurance from your solar installer.
Your solar installer should have general liability insurance covering ongoing and completed operations to be fully insured for any 3rd party bodily injury and property damage that they could cause in the course of their doing business.
If you are installing a large commercial solar system, talk to your insurance broker to make sure you are properly indemnified in your contractual agreements with the solar installer.