1. DC Solar Panel Capacity
DC capacity is the total power your solar panels can produce under lab testing conditions.
It’s measured in DC kW
For example, if you have 20 solar panels rated at 350 watts each, your system's DC capacity is 20×350W=7,000W (or 7 DC kW).
2. AC Inverter Capacity
AC capacity is the maximum power your inverter can export to your home or the grid.
The inverter converts the electricity from DC (produced by your panels) into AC, which is what your home uses.
For example, your inverter might have a capacity of 5 kW AC. That means it can send a maximum of 5 kW of power at any given moment.
DC Electricity needs to be converted to AC for your home, which is why it will always be a little less.
Why is the DC (Panels) Capacity Bigger Than the AC (Inverter) Capacity?
Your panels rarely produce their full potential due to real-world factors like weather, shading, or time of day.
By slightly oversizing the solar panel capacity (DC), your system can make the most of the inverter's output, even when the sun isn’t shining as brightly.
This design maximizes energy production throughout the day.
Will My System Waste Power if Panels Make More Than the Inverter Can Handle?
Sometimes, yes, but only for short periods on very sunny days. This is called “clipping”—when the panels generate more power than the inverter can process.
In the first few years, when your panels are at their peak performance, there might be a small amount of clipping on very bright, sunny days.
Clipping happens when your panels produce more power than the inverter can convert to usable electricity.
This only occurs for short periods, and most of the energy your system generates will still flow through just fine.
Don’t worry! This is planned and ensures your system performs efficiently year-round.
Why This Design Saves You Money Over Time
As solar panels age, their production decreases slightly each year (usually by about 0.5–1% annually).
Over time, the energy your panels produce will naturally fall below the inverter’s maximum capacity. By then, clipping won’t happen anymore.
With this design, you:
Avoid paying for a larger, more expensive inverter that you won’t need later.
Save more money upfront and long-term, while still enjoying excellent system performance.
Example to Help You Understand:
System A:
Panels: Produce 6 kW (DC).
Inverter: Handles 5 kW (AC).
On very sunny days, some power might be capped (clipping) for short periods, but most of the energy your system produces will still be used.
Lower Cost Upfront: The smaller inverter saves you money at installation.
Long-Term Savings: As your panels naturally produce less power over time, clipping will stop, and your system will continue to perform efficiently for decades.
The Best Choice: Our team has carefully modeled the long-term performance of systems like this, and we’ve found that it saves customers the most money over time.
System B:
Panels: Produce 6 kW (DC).
Inverter: Handles 6 kW (AC).
No clipping, even on the sunniest days, so you capture all the energy early on.
Higher Cost Upfront: The larger inverter adds to the system’s installation cost.
Less Efficient Long-Term: As your panels age and produce less power, the extra capacity of the larger inverter will go unused, making the upfront cost less valuable over time.
Why System A is the Better Choice
Our team has run detailed performance and cost models, and System A consistently delivers the best balance of value and energy production.
By using a slightly smaller inverter, you save money upfront and avoid paying for extra inverter capacity that won’t be needed as your panels age.
While there’s a small amount of clipping in the first year or two on very sunny days, the savings over the system’s lifetime far outweigh any minimal loss in energy.
Built for Long-Term Value
With System A, you’re choosing a design optimized to save you money and deliver reliable energy for decades. If you have any questions, our team is happy to explain more or show you how we calculated the savings!