TSRF, What Is Total Solar Resource Fraction?

News articles about renewable energy attract the attention of responsible homeowners. However, increased reports of storms, drought and rising sea levels cause Americans to worry. In addition, global warming gases that overload our atmosphere increase concerns. Fortunately, almost everyone knows that energy comes from the sun. In addition, most homeowners know that solar panels can harness it. A formula can show you how much energy they can capture.

Understanding the Total Solar Resource Fraction (TSRF)

The TSRF lets you know how well your roof can work with solar panels. Specifically, it determines how much sun hits your home. Powerful enough to provide electricity to the world’s entire population in one hour, the sun’s energy only needs harnessing. Solar panels protect the environment and lower your utility bill. The abundant sunshine in the great Northwest invites you to use it to an advantage.

Your roof’s pitch makes a difference in generating solar energy. The direction it faces matters too. The shade that covers your roof also influences it. After you see how each factor affects your house, you can find how much benefit solar panels on your roof can provide.

• Tilt

The amount your roof tilts controls how much sun it can get. Its angle or slope produces a number in degrees that you may already know. As a homeowner, you may know the pitch of your roof. For example, a rise and run of an 8/12 pitch makes it pretty steep. It means that it rises 8 inches for every foot of length, producing a 34-degree tilt.

• Orientation

Solar energy experts usually combine tilt and orientation into one factor that abbreviates as the TOF. Together, the slope of a roof and the direction a surface faces controls how much solar energy it receives. Solar panels that face south may produce more savings on electric bills than others that face a different direction. 

The equator receives the most direct sun, and homes in the United States lie north of it. Thus, roofs that face south likewise receive more sunlight. However, many homes do not face south. Still, you have alternatives that can work instead. For example, adding more panels can make up for a roof that faces north, east or west. In addition, a ground-mounted array of panels in your yard can face south if you have the space. 

• Solar Access

As another way to refer to shade or nearby buildings that block the sun, solar access provides an important measure. It determines how much sun your roof can get. Thus, it represents the percentage of the roof area that receives no shade. Full access to the sun presents ideal conditions for solar panels, but it rarely happens.


Calculating Your TSRF

When you multiply your TOF by your solar access percentage, you can find your Total Solar Resource Fraction. It tells you the amount of space on your roof without shade and with the perfect tilt and orientation. The combined factors produce a more accurate picture than either can do alone.

Considering the Potential of Your Rooftop

A statistic from the Department of Energy (DOE) shows that rooftops in the U.S. provide more than 8 billion square meters of space suitable for solar panels. All of the space included in the report meets the requirements for TRSF factors for tilt, direction and shade. 

In addition, the size and location of the homes make them suitable as well. However, the statistic does not account for the cost or availability of solar panels. Still, it shows the enormous potential for preserving the environment and lowering utility bills. Residential rooftops, along with other small rooftops, account for about 65 percent of the total potential space in the country.

Choosing an Easier Way to Find Your TSRF

You may choose to use an online tool that does the math for you. For example, one of DOE’s Incubator Program award recipients produced software that can calculate your roof’s sun friendliness. As an alternative to calculating the TSRF by hand, in case you do not especially enjoy doing math problems, you may use it instead. The software developers call it a Sun Number. 

 When you click on Calculate Now after you type in your ZIP code and other information, the software gives you a numerical score. The scale goes up to 100 to indicate the ideal rooftop potential. Roof pitch, orientation, size and shading score points that help define your home. Any score above 70 makes your home capable of benefiting from solar energy. 

Sun Numbers come from aerial imagery with techniques that calculate shape, nearby buildings, vegetation, atmosphere and regional differences. 

Using Online Tools to Learn More

As a homeowner, you can estimate your solar energy savings based on electricity bills at EnergySage. In addition, PVWatts can estimate costs and production for systems that connect to the grid. Similarly, the System Adviser Model (SAM) can show you a financial analysis of renewable energy systems. SAM calculates a range of factors that affect the performance and costs of potential projects for businesses as well.

The incubator program at DOE provides access to rooftop solar potential through various awardees. Business owners can check with Aurora Solar to assess the potential for possible building locations. DGEN: Distributed Generation Market Demand analyzes data that affects markets as a guide for business owners. In addition, the National Solar Radiation Database provides access to meteorological data on TRSF factors that affect performance.

Choosing the Benefits of Technology

Homeowners who care about protecting the environment can receive financial benefits from lower electric bills. At Impact Energy, we offer systems that capture and harness the abundant energy in the magnificent Northwest. 

As a renewable source with no limits, solar energy gives you independence from failed service by electric companies. Storms that damage transmission lines or blackouts from overloads can deprive you of power beyond your ability to control. A solar panel and battery storage system lets you access electricity whenever you need it. As a result, a growing number of informed and concerned American homeowners choose solar systems for efficiency, convenience and protection of the environment. Whether you calculate your TSRF by hand or use an online tool, it can show you the potential your roof has for an energy-producing solar panel system.