Millions have been left without power from extreme weather events. With recent hurricanes increasing in size and strength, FEMA has laid out recommendations for preparing solar panels to ensure self-reliance in case the grid fails. From the design aspect, one of those recommendations is to implement microinverters versus string inverters when getting your solar panels installed.
Panels experience impediments like cloud coverage, shade from overgrown trees, or even leaves. When it comes to high wind events, most solar panels can withstand up to 140mph of winds, or a Category 4 hurricane, according to NOAA.
However, if one part of an array is impacted by any of these things with a string inverter, all panels will be impacted. Microinverters that attach to each panel prevent a widespread issue. So, for example, when one panel or microinverter fails, the rest of the array is still pumping out power. This is why solar panels designed with optimal operation in mind can help families and businesses stay in play when the power grid goes down.
9 reasons why FEMA recommended microinverters:
- One area failure doesn’t cause an entire system failure. Microinverters that fail only impact the panels they are connected to, unlike string inverters, where the entire system will go down if one area is affected. So if one panel blows off the roof, the rest will continue working unaffected by the damage.
- Remote troubleshooting – with string inverters, the installer must make an in-person visit to diagnose the movement. Microinverters allow for remote problem-solving, and if an in-person repair is necessary, the installer will know the problem ahead of time, which makes for speedy repairs.
- Flexible designs – microinverters are flexible because, unlike string inverters, they don’t require continuous string installation.
- Increased durability – inverters are one of the first pieces of equipment to fail; microinverters tend to be more dependable and durable than string inverters.
- Microinverters have lower voltage DC conversions meaning the DC to AC conversion happens at the panel level, which removes the danger of high voltages traveling through the entire system.
- Reduces high voltage traveling the system as well as fires and arc faulting – which is when loose, faulty wiring causes sparks and, ultimately, electrical fires.
- Faster and easier to install – microinverters require less electrical work, and no DC electricians are required.
- Increased productivity – microinverters, on average, have a 3% higher equipment productivity level.
- Microinverters tend to have longer product warranties.
A standard for microinverters
William May, the owner of May Electric Solar and a Solar Insure Certified Installation Company, discusses the standard he has set for solar designs to include microinverters.
Preparing for an extreme wind event
Most solar panels can withstand up to 140 mph winds, which is around 2,400 pascals (the unit in which solar panel wind resistance is measured). That’s sturdy enough to withstand a Category 4 hurricane, whose wind speeds range from 130 to 156 mph.
Rooftop solar owners can take a series of actions before a strong wind or storm event occurs. We’ve adapted the following list for homeowners based on NREL’s recommendations.
Pre-Storm Solar PV checklist:
- Clear the exterior of all debris and tie down loose items or equipment
- Trim trees and shrubbery that could cause damage to your house or panels
- Install roof drain covers
- Check those drainage systems are cleared and functioning
- Check and have modules, fasteners, and framing tightened
- Check hardware for any corrosion, missing or damaged parts and have them replaced
- Check racking hardware for looseness and have it tightened if needed
- Have professional check electrical, connectors, wiring, J-box, PC cables connections, gasketing, conduit fittings
- While the extreme weather event passes, NREL recommends powering down the system and turning all disconnects to the open position
Microinverters aren’t just for high wind-prone regions
The push toward microinverters can be seen with top-rated installers who want to keep their customers happy and solar panels working at top performance levels. Using microinverters in the planning and design processes shows the installers’ level of responsibility to their customers. Now, that’s not to say string inverters don’t have their place; however, it’s clear that a shift toward microinverters is becoming the norm, and customers are willing to pay more for savings down the line because true value comes when our solar systems are up and running with little to no downtime.
The Solar Insure team supports customers on their journey with solar power, and our mission is to deliver the most peace of mind a solar customer can get.
Learn more about what Solar Insure means to homeowners: https://www.solarinsure.com/for-homeowners