One important metric to consider when comparing solar panel options is a panel’s power rating, referred to as wattage. 400-watt (W) solar panels are above the average wattage of solar panels available today and can be a solid panel option for many types of solar projects.
Most solar panels installed on homes or businesses today are between 250 to 365 watts per panel, and solar panels above and below that range are also available. In order to determine if 400W solar panels are right for you, it is important to understand what the options are and how much energy 400W panels produce.
What are 400W solar panels?
A 400w solar panel produces an output of 400 watts of electricity, and it can be used for both commercial and residential solar projects. 400w solar panels will produce approximately 1.2 and 3 kilowatt hours (kWh) daily, of course depending on their exposure to sunlight and other factors including geographic location and tilt.
List of 400W solar panels
Not many companies manufacture truly 400W solar panels. Below is a selection of solar panels that produce close to 400W of power, each listed with their efficiency and the company that makes them.
List of ~400-watt solar panels
| Manufacturer | Panel model | Wattage (W) | Panel efficiency (%) |
|---|---|---|---|
| Hanwha Q CELLS | Q.PEAK DUO L-G5.2 380 | 380 | 18.9 |
| Hanwha Q CELLS | Q.PEAK DUO L-G5.2 385 | 385 | 19.1 |
| Hanwha Q CELLS | Q.PEAK DUO L-G5.2 390 | 390 | 19.4 |
| LG | LG375N2W-G4 | 375 | 19.1 |
| LG | LG390N2W-A5 | 390 | 18.8 |
| LG | LG395N2W-A5 | 395 | 19.1 |
| LG | LG400N2W-A5 | 400 | 19.3 |
| LG | LG405N2W-A5 | 405 | 19.5 |
| SunPower | SPR-E19-410-COM | 410 | 19.1 |
| SunPower | SPR-E20-435-COM | 435 | 20.3 |
How many 400-watt solar panels do you need?
The number of solar panels you’ll install depends on the amount of electricity you want to generate and the space available for solar panels. Many people choose to go with the 400W solar panel due to a lack of roof space; this is because 400w solar panels produce electricity more efficiently than many lower-wattage solar panels given the space they take up. The table below compares different sized solar panel systems by the number of 400W solar panels needed for each system size. In some cases, the number of 400W panels is rounded to the nearest panel.
How many 400-watt solar panels do you need? System size comparison table
| System size (kW) | Number of 400-watt solar panels | Estimated space needed (sq. ft.) |
|---|---|---|
| 2 kW | 5 | 114 |
| 5 kW | 13 | 296 |
| 6 kW | 15 | 341 |
| 7 kW | 18 | 410 |
*Number of panels rounded to the nearest panel, and space needed rounded to the nearest foot
Using five 400W solar panels will produce roughly 3,000 kilowatts hours (kWh) of electricity, which is significantly below how much electricity a standard single-family household uses. Installing 15 panels for a roughly 6 kW system will produce enough electricity to significantly offset or eliminate your electric bill with solar.
How much space will a solar energy system using 400W panels take on your roof or property? The table below demonstrates estimates for solar energy systems using only 400W solar panels. For the purpose of calculating estimated space needed, we assumed that 400W solar panels are, on average, 22.75 square feet (6.5’ by 3.5’).
How much space will a solar installation with 400-watt solar panels take?
| System size (kW) | Average annual kWh production | Number of 400W solar panels (rounded) |
|---|---|---|
| 2 kW | 2,820 | 5 |
| 5 kW | 7,050 | 13 |
| 6 kW | 8,460 | 15 |
| 7 kW | 9,870 | 18 |
*Number of panels needed rounded to the nearest panel, and assumes a production ration of 1.41
Solar panels close to 400W are relatively efficient with the space they use when compared to lower wattage panels, and a standard roof of a single-family home will likely have enough space for the number of panels needed to significantly offset electricity costs. If you have a small roof or even a roof you don’t want to be covered in panels, consider a ground-mounted solar system.
Are 400-watt solar panels right for your solar installation?
400W solar panels are above the average wattage of panels used for most solar installations but still will make sense for some property owners. While they may be more expensive per panel than lower wattage options, 400W panels make up for the price premium in the space they save on your roof and the lower number of panels you will need to purchase to cover your electricity needs.
Whether you’re looking for low, standard, or high wattage panels, you can get multiple solar quotes from pre-screened installers by signing up on the EnergySage Solar Marketplace. If you have preferences when it comes to solar equipment, you can simply note them in your account so installers can quote accordingly. If you’d prefer to start investigating your solar options with a quick estimate on what solar can save you, try our Solar Calculator.
