400-watt solar panels are one of the biggest panels you can buy. These are relatively new. Up until a few years ago, panels of this size were not possible. But with the latest technology, solar panels are getting bigger and more efficient.
The panels of this size are excellent for residential power. You can connect one or more 400-watt solar panels to power an entire house.
To fully understand what can you get out of a panel of this size, you need to know a few basics.
Let’s start with a few basics.
- A 400-watt solar panel cannot produce 400 watts at all times. This power rating signifies its maximum output under the ideal situation.
- A solar power system has to encounter several transmission and conversion losses that prohibit it from reaching its full potential in real conditions.
- A battery is vital if you want to get full benefits from your power system.
Size and weight of a 400watt solar panel
The size of a 400-watt solar panel is around 80 x 40 x 1.5 Inches (202.4 x 102.4 x 4cm), which makes it over 6.5 feet in length and more than 3 feet in width. You can expect slight size variations with different brands.
A 400-watt solar panel weighs 44lbs or 20kgs
400 Watt Solar Panel Price
A 400-watt solar panel costs around $650 without a battery kit
400-watt solar panels are not only expensive than smaller panels in general, but they also cost more per watt of power
Their higher cost is due to their cost-intensive manufacturing process.
You can easily expect to shell out 10% more on these panels.
Due to the higher cost and massive size of 400-watt solar panels, most users opt for alternative arrangements like joining several 100-watt or 300-watt panels until they can get the desired power output.
How much power does a 400W solar panel produce?
The actual power output of a 400-watt solar panel depends on your location. However, you can get a fairly reasonable estimate.
There is a simple formula to calculate the power output of a solar panel.
E = A * r * H * PR
E = Energy (Kwh)
A = Area of your solar panel (m2)
r=solar panel yield or efficiency (15%)
H= Average annual solar radiation on tilted panels
PR= Performance ratio (Average Value = 0.75)
We have gathered data of all the states and calculated the average power you can get in a day to simplify things. These values present the average values; the power output you are going to get may be different.
| Code | State/Province | Average Annual Solar resource in kWh/m2/day | Average Daily Solar Power in Watts |
| AL | Alabama | 5 | 1150 |
| AK | Alaska | 3.5* | 805 |
| AZ | Arizona | 7.1 | 1633 |
| AR | Arkansas | 4.45 | 1023.5 |
| CA | California | 7.2 | 1656 |
| CO | Colorado | 6.2 | 1426 |
| CT | Connecticut | 4.5 | 1035 |
| DE | Delaware | 4.7 | 1081 |
| DC | District of Columbia | 4.7 | 1081 |
| FL | Florida | 5.3 | 1219 |
| GA | Georgia | 5 | 1150 |
| HI | Hawaii | 6.5 | 1495 |
| ID | Idaho | 4.7 | 1081 |
| IL | Illinois | 4.6 | 1058 |
| IN | Indiana | 4.3 | 989 |
| IA | Iowa | 4.7 | 1081 |
| KS | Kansas | 5.7 | 1311 |
| KY | Kentucky | 4.45 | 1023.5 |
| LA | Louisiana | 5.2 | 1196 |
| ME | Maine | 4.3 | 989 |
| MD | Maryland | 4.55 | 1046.5 |
| MA | Massachusetts | 4.5 | 1035 |
| MI | Michigan | 4.25 | 977.5 |
| MN | Minnesota | 4.7 | 1081 |
| MS | Mississippi | 5.2 | 1196 |
| MO | Missouri | 4.8 | 1104 |
| MT | Montana | 4.6 | 1058 |
| NE | Nebraska | 5.4 | 1242 |
| NV | Nevada | 6.4 | 1472 |
| NH | New Hampshire | 4.4 | 1012 |
| NJ | New Jersey | 4.5 | 1035 |
| NM | New Mexico | 7 | 1610 |
| NY | New York | 3.9 | 897 |
| NC | North Carolina | 5 | 1150 |
| ND | North Dakota | 4.9 | 1127 |
| OH | Ohio | 4.2 | 966 |
| OK | Oklahoma | 5.9 | 1357 |
| OR | Oregon | 5.4 | 1242 |
| PA | Pennsylvania | 4 | 920 |
| RI | Rhode Island | 4.7 | 1081 |
| SC | South Carolina | 5.2 | 1196 |
| SD | South Dakota | 5.2 | 1196 |
| TN | Tennessee | 4.7 | 1081 |
| TX | Texas | 6 | 1380 |
| UT | Utah | 6.2 | 1426 |
| VT | Vermont | 3.9 | 897 |
| VA | Virginia | 4.7 | 1081 |
| WA | Washington | 4.5 | 1035 |
| WV | West Virginia | 4.2 | 966 |
| WI | Wisconsin | 4.4 | 1012 |
| WY | Wyoming | 5.6 | 1288 |
What can a 400-watt solar panel run?
As you can see, the average daily power output of a 400-watt solar panel ranges from around 805 Wh/day to over 1656 Wh/day in the united states. If we average out all the values in the table, we have 1150 Wh/day.
Please understand that there are two kinds of power outputs; instantaneous power and accumulated power.
Instantaneous power is represented by 400 watts. The daily power output we have calculated comes under accumulated power.
What you can run on your solar panels depend on accumulated power.
| Device | Power | Run time (If You Used Only One Device) |
| 60 Watt Bulb | 60W | 19 Hours |
| LED | 6W | 192 Hours |
| Cell Phone | 5W | 230 Hours |
| Laptop | 42W | 27 Hours |
| Fridge | 80W | 14.4 Hours |
| DC Fridge | 170W | 6.8 Hours |
| Heater | 1000W | 1.15 Hours |
| Booster Pump | 60W | 19 Hours |
| Blender | 500W | 2.3 hours |
Can a 400-watt solar panel run a refrigerator?
Yes, a 400-watt solar panel can run a small fridge (80 watts) or a DC Fridge (170 watts). However, you will need a battery to accomplish that; and you can expect an average runtime of about 14.4 hours for an 80W fridge and 6.8 hours for a DC fridge in a day.
Please note that these values will vary considerably based on your location, weather conditions and usage.
Can a 400-watt solar panel run an air conditioner?
A 400-watt solar panel can power an air-conditioner for a short duration. The smaller air conditioner used in RVs has a power rating of 1000Watts to 1500watts. With a daily charge of 1150 Wh, you can barely run an air conditioner for 46 minutes to 1.15 hours which is not a suitable option.
Final Thoughts
A 400-watt solar panel can be a wonderful addition to your home or RV. It can run most appliances without any problems. If you combine a few 400-watt solar panels, you can easily power a whole home with adequate sunlight.