The most important part of any solar system is not the solar panel, it is the solar inverter. The inverter is what converts the sun rays from DC to AC electricity, which is what you use in your home. Unlike solar panels, where there are 50+ options the choose from, virtually all solar systems in the United States are installed with one of the following types of inverters.
Micro-inverters go directly behind a solar panel and allow each to function independently. Both Enphase and Sunpower Micro-Inverters come with 25 year warranties (although Sunpower Micro-Inverters offer an AC power output warranty). With micro-inverters, you can expand the system to as many panels as needed, at any time. Micro-inverters do not experience line loss like string inverters, so they create more power than the same sized string inverter would.
At Heliogold, we only install systems with either Enphase Micro-Inverters, or Sunpower Micro-inverters (if part of the Sunpower Equinox System). We believe firmly that all systems are much better off with micro-inverter technology.
A string inverter essentially connects an array, or arrays of solar panels, like christmas lights. If one panel has an issue, it can cause the entire system to have the same issue. If the panel goes out, everything behind it can also go out. Most importantly, when the string inverter does not work, nothing works. String inverters without optimizers are the cheapest way to go solar. No string inverter is expected to last 25 years, and most come with a warranty of 10-12 years. Many of these warranties can be extended to 20 or 25 years, but that is a sucker bet in our opinion. The expected lifetime is closer to 10 years as opposed to 20. String inverters tend to be bulky, and the conduit cannot be run in through the attic, so aesthetics suffer as a result.
String Inverter with Optimizers
An optimizer is an electrical component that allows string inverters to work like micro-inverters. It’s similar to lipstick on a pig however, in that if the string inverter does not work, optimizers do not help. You also run into the same issue of future expansion, regardless if you add optimizers to a string inverter.