4kW Solar System

4kW solar system

Picking together the components of a solar system can be challenging for a newcomer. Here in this section of our website we offer precombined systems that are ready to be installed.

How a 4kW solar system is used

The most popular type of configuration is a grid-tie system. Solar panels power your appliances, but you can lean back on electricity from the commercial grid at any moment. You can use commercial electricity on cloudy days and at night when rates are generally lower anyway. Excess solar energy can be sold into the grid for credits from your utility that are used to cover your bills.

How much electricity does a 4kW solar system produce? On a good sunny day a 4 kW system makes around 4 kWh of energy in an hour. The production is influenced by the following factors:

• Weather. On cloudy days irradiance of panel falls and the output decreases by 20-40%;
• Positioning and angle. In the northern hemisphere you want your panels facing south, inclined at 30 to 45 degrees;
• Temperature. Panels work best when it’s cold and sunny. Their performance drops when it starts getting over 77 °F;
• Shading. Shade impacts different panels differently, but they lose energy no matter what.

So how much does a 4kW solar system produce per day? That depends on location and more specifically the number of peak sun hours in your state. For instance, in California the average number of sun hours per day over the year is 5.6, whereas in New York it varies from 3 to 3.5. Thus in Los Angeles a 4k solar system makes 4 kW × 5.6 h = 22.4 kWh per day on average throughout the year. Keep in mind, however, that in summer panels produce 50% more energy than in winter.

A 4 kW solar system can also be used in a house without any connection to the grid — it’s called an off-grid system. It is imperative to have batteries as a backup. Your appliances will draw the power from your battery bank at night and on gloomy days when panels don’t generate enough. The option of a net metering is not available though, and the system costs a bit more because of the batteries.

4kW solar system cost

Panels have been continuously getting cheaper over the years. They were 80% more expensive 10 years ago. Not only that, but the incentives from the government also make a switch to solar much cheaper. If you live in the right state and if you’re lucky, you can basically get your system for half-price by applying for different solar programs.

So how much does a 4kW solar system cost? Generally, it would cost around $10,000–15,000, including installation services and shipment. However, Solar Tax Credit, a federal program that is available to all Americans, allows you to reduce the costs by 26% in 2022, bringing the average cost to $7,000–12,000.

A lot depends on the panels though. There are cheap models and there are premium-class expensive ones. A 4kW solar system price is going to be the lowest if you go for Chinese panels. The brands that you are looking for are Trina, Jinko, JA Solar. American panels are a bit more expensive, but the quality is higher. Brands like Canadian Solar, Silfab and Aptos Solar represent North America on the world’s market. The most expensive panels come from companies like Panasonic, Sunpower, LG. While the 4 kW solar system cost is going to be higher than average with these panels, they come with great warranties, perform better in most circumstances and last longer.

What 4kW solar kit includes

The components of your solar system may vary depending on the design that you choose. Grid-tie system is the most simple one. The required parts are:

• solar panels;
• grid-tie inverter.

While you can add batteries to your sub electrical panel for critical loads, you should keep in mind that during power outages all grid-tie inverters shut down. It means that a grid-tie 4kW solar panel system won’t help you during a blackout. What will help you though is a hybrid system. It includes:

• solar panels;
• hybrid inverter;
• battery;
• charge controller.

Sometimes hybrid inverters have a built-in energy storage and a charge controller. Hybrid inverters ensure uninterrupted power supply for your home: if a power outage happens, the inverter just switches your house to battery support.

Sometimes, however, there are no power lines to speak of. That’s when an off-grid system comes in handy. It includes:

• solar panels;
• off-grid inverter;
• batteries;
• charge controller.

Keep in mind that the average size of a system in the US is 5–6 kW — such a system covers about 80%-90% of the energy needs of an average American house. A 4 kilowatt solar system might be enough for small houses, but you would need more power for a larger one.