What is the Right Solar System for Your Home: 10kW Solar System vs. 9 kW Solar System

When going solar, homeowners must decide which system is right for their home. One of the key factors is the system kilowatts (kW). This is the unit of power that measures the maximum amount of energy the system can produce under ideal conditions. Each kilowatt equals 1000 watts. 

Homes can typically reach solar goals with a 10kW or 9kW system. But which is right for your home? There are several factors to consider when making your decision.

How Much Power Does a Solar Panel Produce?

The amount of power a solar panel produces will vary depending on the exposure to sunlight and the panel's efficiency. However, a quality solar panel will generate between 250 and 400 watts of electricity. Solar panels typically start at 1kW and produce between 750- and 850-kilowatt hours (KWh). 

A typical household needs around 10,000 KWh per year. A 20 to 30-panel system should cover these energy needs. However, there are other factors to consider. 

Cost

Homeowners must find a system that suits their budget. So how much does each system cost? The amount will vary based on the state you live in, the contractor, and the equipment. However, country-wide averages show the following:

• 10 kW: $30,000

• 9kW: $24,930

You must also consider the federal tax credit. It allows taxpayers to reduce 30% of the total cost of their system from their tax payments. However, the percentage will decline over the years and, unless renewed, it will expire in 2035. 

The percentage is relevant because- the more you spend on your system the bigger credit you will get. Additionally, a larger system will provide more energy and help you save more on your electric bill. Therefore, households that use a lot of energy may want to spring for a 10-kW system. 

Electricity Generation

The amount of energy the system generates depends on your location. If you live in a climate that gets lots of sunshine, your system will produce more energy. However, there are averages to consider as follows: 

• 10 kW: 11,000 to 15,000 kW of energy per year

• 9 kW: 9,000 to 13,000 kW of energy per year

Size

The size of the system is another factor. You must determine if your roof is large enough to hold your system. 

Both 9kW and 10kW systems consist of about 25 panels which take up 440 to 475 feet of roof space. However, panels are getting more efficient which means you may generate the same electricity with fewer panels. Speak to us to learn how big of a system your roof can handle. 

Electricity Bill Savings

Your electricity use may be the biggest factor to consider when choosing the panels that are right for you. On average, U.S. homeowners save about $125 per month 

However, this number will vary depending on the amount of energy your panels produce, the cost of electricity in your area, and your local net metering policy. 

Can a 9kW or 10 kW System Power a Home?

Both a 9kW and 10kW system can power a home. In fact, in some instances, they may provide too much energy. 

For example, homes in Louisiana, which tend to be large and require air conditioning a good portion of the year, may get along with a 9kW or 10kW system and see substantial energy savings. New York homes, which are smaller and don’t use as much energy, may not need such a large system. 

9kW and 10kW systems may be better suited to larger commercial spaces.

What is the Average kWH for Residential Solar Systems?

9kW and 10kW are large for residential solar systems. Most home solar systems are between 6-8 kW. A system such as this would use about 20 solar panels producing 240 to 400 watts each. 

However, the size of the system you choose will depend on your electricity use, your roof space, and local sunlight conditions. 

Other Factors to Consider

The kW your system produces is a key consideration. Here are other factors to consider when determining the system that’s right for you. 

Panel Type

There are three main panel types: polycrystalline, monocrystalline, and thin film. Here are some guidelines to consider when choosing the panels that are right for you. 

• Monocrystalline: These panels are the most efficient of the three with a power capacity of 320 and 375 watts. They are made from pure silicon crystals which enables them to convert more sunlight than other types of panels. They are also more expensive than their countertops. 

• Polycrystalline: Polycrystalline panels are made from fused silicon crystals. Their efficiency typically ranges from 240 to 300 watts. They are less expensive than monocrystalline panels, but more expensive than thin-film. 

• Thin-Film: These panels are made from various materials, each of which has its advantages and disadvantages. Unlike monocrystalline and polycrystalline panels, they do not have a standard efficiency. However, they are not as efficient, or as expensive, as other panel types. 

Although monocrystalline panels are the most efficient, they can be too powerful for some properties. If your household does not consume a lot of energy, you may do just as well with another panel type and save money while you’re at it. 

Additionally, not all panels of the same types are created equal. You must also consider:

• Power Rating: The power rating of each panel is measured in watts. The higher the power rating, the more efficient the panel. 

• Panel Efficiency: The panel efficiency measures how much of the energy produced is converted into usable energy. Typically, efficiency is between 15% and 20%. 

Panel Color

Each panel is composed of silicon cells placed on a back sheet. The back sheet shows a grid-like design through the cells. Traditional back sheets are white. However, some manufacturers offer black sheets which produce a seamless aesthetic for dark roofs. 

However, black sheets also absorb more heat which could reduce the system’s efficiency. 

Homeowners should also consider the color of the metal frame around the panel borders. Frame colors are typically black or silver. Black may be more aesthetically pleasing, but it also costs more. Both perform identically. 

Solar Panel Size

Solar panels typically come in two sizes: 60-cell and 72-cell. It refers to the number of cells on the panel. It also affects the size- 72-cell panels are typically about a foot longer than 60-cell panels. 

72-cell panels are ideal for larger spaces typically found on commercial roofs. 60-cell panels are more suited to homes. 

Generally, 72-cell panels are more economical as they generate more electricity per panel than their smaller counterparts. However, they are more than enough for most homes. Residences typically choose the 60-cell panel as it fits well on most rooftops and meets production and budgeting needs. 

Quality

Several factors support panel quality. Here are some to consider.

Manufacturer Tier 

A good manufacturer will produce quality panels. But how do you know how good the manufacturer is? You can look at consumer reviews, but the manufacturer tier is the most telling sign. 

There are three manufacturer tiers as follows:

• Tier 1:  Provides products to 61.5+ MW Projects Financed Non-Recourse by 6 different banks in the past 2 years. 

• Tier 2 & 3: Not published by Bloomberg NEF.

Although consumers may think Tier 1 brands are more reliable, this isn’t necessarily true. Bloomberg New Energy Finance Corporation (BNEF) measures brands according to how bankable the company is. Bankable companies typically offer quality products. However, several non-bankable companies provide products just as efficiently. 

Durability

Solar panels should hold up to weather conditions like high winds, heavy rain, and snow loads. Indicators like IEC 61251 will give you an idea of the panels’ durability. It will also reveal how the panel performs in different climates. 

Brand Reputation

Factors beyond the manufacturer tier will indicate the brand’s reputation. You must consider:

• History and Experience: Brands that have been in the industry for some time will build up a reputation for serving customers. They will know how to deal with unexpected issues. 

• Financial Stability: A financially stable company will be more likely to honor warranties. They are also more likely to stay in business throughout the lifetime of your panels to provide ongoing support. 

Customer Reviews and Industry Ratings: Research to find out what customers and industry insiders are saying about the brand. 

Roof Considerations

Your roof type and location will not affect the type of system that’s right for you. However, it will impact your installation costs and energy output. 

Not every roof is ideal for solar installation. Almost every roof (except for glass) can handle solar, but some will need extra preparation that can add to installation costs. 

Additionally, if your roof is in a shady area, it will not absorb as much sunlight. These conditions will reduce your system’s output. Your contractor may recommend that you trim or remove trees to provide your panel with more access to sunlight, but this will also add to costs. 

The Right Contractor Matters

Getting the right system is essential, but it’s equally as important to find the right contractor. A trusted contractor will provide efficient installation and various financing options. They will offer reasonable prices and quality equipment. 

Solar America can help you connect to the best contractors in your area. Simply enter your contact information on your website form. Our database will come up with various installers in your area. Our competitive system means contractors vie for your business offering the lowest prices. 

Contact us to make going solar a breeze.