If you're considering installing solar panels on your home or business, you'll need to decide whether to use a system involving one inverter or several micro-inverters. Understanding the difference helps you make the right choice for your situation.
What is a Standard (String) Inverter?
A string inverter is a single inverter that connects all the solar panels in a "string" and converts the combined DC power from the panels into AC electricity. It's the most common and cost-effective inverter configuration for residential and commercial solar systems.
Pros of string inverters:
- Lower upfront cost
- Simple, proven technology
- Easy to monitor and maintain
- Wide range of reputable brands available
Cons of string inverters:
- Performance of all panels is limited by the weakest panel in the string
- Shading on one panel can reduce output of the whole string
- Single point of failure for the entire system
What Are Micro-Inverters?
Micro-inverters are small inverters — one per panel — mounted directly on or near each solar panel. Each panel operates independently, converting its own DC output to AC separately.
Pros of micro-inverters:
- Each panel operates independently — shading on one doesn't affect others
- Panel-level monitoring: you can see exactly how each panel is performing
- No single point of failure for the whole system
- Easier to expand the system in future
- Generally longer warranties (many offer 25-year warranties)
Cons of micro-inverters:
- Higher upfront cost (typically 20–30% more than string inverters)
- More components means more potential maintenance points
- On unshaded roofs with uniform panel conditions, the performance difference is minimal
DC Optimisers: A Middle Ground
DC optimisers (from brands like SolarEdge) are a third option. They're panel-level electronics that allow each panel to operate at its optimal output, which is then sent to a single central inverter. This delivers many of the shading benefits of micro-inverters at a more moderate price premium.
Which Should You Choose?
For most standard residential roofs with minimal shading and uniform panel placement, a quality string inverter from a reputable brand (Goodwe, Fronius, SMA) offers excellent performance and value.
Consider micro-inverters or DC optimisers if:
- Your roof has complex shading from trees, surrounding buildings, or chimneys
- Panels will be mounted on multiple roof faces at different orientations
- You want the most detailed panel-level monitoring data
- You plan to expand your system in stages
Need Expert Advice?
EFS Solar's design team will assess your specific roof and recommend the optimal inverter configuration for your situation. Contact us today for a free consultation and quote.