How Solar Installers Design Your Solar Panel System!

solar panel design

The process of of how solar installers design a solar energy system is often a mystery for most consumers. Because of this, we would like to give you some insight into how solar installers design a solar power system for your home or business. A solar power system is designed considering two important factors – the amount of space that you have available for installing solar panels and the amount of electricity you consume annually. Other factors, like shading analysis and the efficiency of solar panels and inverters also come into play.  

Space to Install Solar Panels

Assuming that you are interested in installing solar panels on the roof, the amount of viable roof space determines the maximum number of solar panels that can be installed. An individual solar panel varies in size, but is usually around 16 square feet in a rectangular shape. The panels are affixed to racking systems that are more efficiently designed when installed in a contiguous space together rather than spread out all over the roof. The available roof space – limited by vents, chimneys, dormers and any required offsets from roof edges or roof-mounted equipment – may limit the system size such that a solar system offsets less than 100% of your annual electricity consumption. The average solar system in the US consumes about 300-400 square feet of space, so your viable roof space may limit the size of the solar system you are able to install. In this case, installers may recommend higher efficiency panels that generate more electricity per square feet than standard panels. These will also come at a higher cost, but is something you might consider depending on your personal goals.

An average solar panel system may generate different amount of electricity based on your location in the world and the orientation of your roof, so installers will use various tools to estimate the viable solar system size. These tools allow installers to use aerial imagery and to “draw” in system designs on your roof space in order to estimate the size of a system that will fit and how much electricity this system will produce each year given a number of assumptions. If you’d like to try this yourself, you can go to PV Watts, a tool developed by the National Renewable Energy Laboratories, to estimate your system size and annual production.

Annual electricity consumption

One of the first information a solar installer might ask for is twelve months of electricity bills. While this might seem like a lot of information right off the bat, this gives the installer a sense for how much energy you use throughout the year. Often an electric bill will include the last twelve months of usage history in a table or a chart, removing the need to fish around for past bills. Armed with your electricity usage information, the installer can determine about how big of a solar photovoltaic system would be required to offset 100% of your annual usage. This will vary by your location and roof profile. Typically, solar panel systems are designed to cover 100% or less of annual usage to maximize the financial benefits, but if you are planning to increase your energy use in the near future – for example, if you are planning to buy an electric car or converting from oil to electric heat pumps – you might consult with your solar consultant to estimate your expected energy demand in order to design a system that better matches that use profile.

The impact of shading

If your roof has shading – from neighboring trees, other buildings or large chimneys – installers may choose to leave these areas uncovered by solar panels to optimize the production of the system or may place panels in these locations with the understanding that these panels may produce less energy at certain times of the day. Installers may also suggest changes to system design to create separate solar panel strings that are designed to avoid power loss from shading or may suggest the use of micro-inverters or power optimizers to help mitigate the impact of shading of the production of the overall system. The latter two technologies may come at a higher cost, but these costs may be justified from the additional power they help your system to generate.

The above factors are taken into account when designing a solar system for your home or business. The process of providing an initial system design can be quite quick and can often be turned around within a day or so. Other factors – such as the structural integrity of your roof, the condition of your existing electrical system or the specific impact of shading – may require that solar installers visit your property to gather additional information in order to develop a system design and a price quote that they can stand by. To get started, get an instant estimate of your solar potential at EnergySage and register to get quotes from a network of pre-screened solar installers.

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Thinking of Installing Solar Panels? Pay Attention to the Solar Panel’s Warranty

Like most technology products that you buy, solar panels come with warranties that help safeguard your investment in the unlikely event that a problem occurs after installation. When evaluating solar panel manufacturers, the two most important warranties on which you should focus are:

1. Product (or materials) warranty, and
2. The performance warranty
We’ll address both of these in this article.

1.  What is Solar Panel Product Warranty?
A solar panel’s product warranty covers the integrity of the panel itself, and protects you against failures due to manufacturing defects, environmental issues, premature wear and tear, etc. Most solar panel manufacturers warrant that their panels will not fail for at least the first 10-12 years, and some extend their warranty periods even longer than that. As with most warranties, a longer period is generally more advantageous to you, if you own your solar panel system. Continue reading

What is the Power Output of a Solar Panel?

You may hear your solar installer say “it’s a 255 Watt panel” or “the panel I am recommending is a 300 Watt panel” or when you are reading a quote from a solar installer and see numbers like 245W or 300W or 345W next to the name of the panel.  They are all referring to a solar panel’s power output.

All solar panels are rated by the amount of DC (direct current) power they produce under standard test conditions. Solar panel power output is expressed in units of watts, and represents the panel’s theoretical power production under ideal sunlight and temperature conditions. Most solar panels on the market today have power output ratings ranging from 200 to 350 watts, with higher power ratings generally viewed as being more favorable than lower power ratings.  Continue reading

What is a Solar Panel’s Efficiency, and Why Does it Matter?

Simply put, efficiency (expressed as a percentage) quantifies a solar panel’s ability to convert sunlight into electricity. Given the same amount of sunlight shining for the same duration of time on two solar panels with different efficiency ratings, the more efficient panel will produce more electricity than the less efficient panel.

In practical terms, for two solar panels of the same physical size, if one has a 21% efficiency rating and the other has a 14% efficiency rating, the 21% efficient panel will produce 50% more kilowatt hours (kWh) of electricity under the same conditions as the 14% efficient panel.  Continue reading


Solar Energy Takes Over Professional Sports

In the past, we’ve written about solar beginning to reach the MLB and the NFL. But since then, more and more professional sports teams are realizing the amazing power of solar energy. In an effort to both reduce their carbon footprint and save money, sports teams across the country are allowing solar power systems to take over their stadiums.

There are so many reasons why going solar is a great idea for anyone from the owner of a large stadium to the owner of a modest residential home. We are optimistic that in the near future every professional sports stadium in the country will be powered by clean, renewable solar energy. Right now, sports fans can follow in the footsteps of their favorite team and go solar themselves! The first step is getting an instant estimate of your property’s solar potential.

Below is a detailed list of the teams and stadiums that have made the switch to solar energy. Continue reading

Solar Loans: The Best of Both Worlds

Solar LoansSolar loans are bridging the gap between purchasing your solar panel system with cash and using a lease or PPA. Like a purchase, a solar loan allows you to own your system and reap the many financial benefits tied to ownership. Like a lease or PPA, it will allow you to go solar with no money down. Today, a host of banks, credit unions and specialty finance companies have emerged presenting a wide range of solar loans. Continue reading

Need Help with Your 2014 Resolutions? Solar Power to the Rescue!

Need Help with Your 2014 New Year's Resolutions? Solar Power to the Rescue!

Need Help with Your 2014 New Year’s Resolutions? Solar Power to the Rescue!

It’s that time of year when everyone starts to think about their New Year’s resolutions. We all want to do better, but let’s face it, sometimes just thinking about the resolutions on your list can be overwhelming. Here’s how going solar can help you meet your 2014 goals without a lot of effort, but some awesome results. We can help you make 2014 the year you finally accomplish everything on your list! Continue reading

EnergySage is helping Organizations Expand Their Sustainability Efforts With Custom Solar Programs

partnership-programSustainability is becoming more and more important, not just to organizations whose missions are focused on it, but also to corporations, non-profits, cities and towns that increasingly feel a social responsibility to embrace it in their own operations. All of this is great news, but what’s even better news is that sustainability isn’t just part of how they operate; it’s becoming part of their culture. More and more organizations are looking beyond their own operations to offer their employees, residents, ratepayers or members turn-key solutions for adopting sustainable practices in their homes or businesses. This includes helping them to adopt solar panel systems and other clean and high efficiency energy systems. And, as always, EnergySage is there to help make shopping for solar photovoltaic systems as easy as possible. Continue reading

Top Five Things To Do with Your EnergySage Case Study

Top 5 Things to Do With Your EnergySage Case Study1.  Convince / Help Others to Adopt Solar or Other Clean Technologies

Research shows that consumers are 24% more likely to implement clean energy systems and efficiency upgrades after seeing them themselves, but schedules being what they are, visiting in person isn’t always possible. Your EnergySage case study, however, is available for review 24 / 7 / 365 allowing people to access valuable data about your real-life experiences living with these systems. Continue reading