Thoughts on Solar

Congratulations, you’ve decided to look into going solar!

Regardless of your reasons…be it economic, environmental, energy independence, or otherwise…it is a sad reality that not everyone can go solar. So how do you know if your property is even a good candidate? Of course, it is important to select a few different installers to do a professional assessment, but even someone with zero solar knowledge can learn how to do a quick preliminary assessment. Here are some simple steps to determining if your home may have a great solar powered future. 

1. My electric bills are killing me!

If your electric bills average $100 or under each month, solar probably won’t be more cost-effective than paying the utility. The costs for permitting, design and engineering all stay the same whether you buy a 3kW system or a 10kW system. Indeed, the labor required to install 5 panels and 10 panels is not very different since installers still have the same amount of electrical ground work. The installation of the actual panels is only a fraction of the total labor. Even the costs of products improves in bulk, so the bigger the system, often the better price per Watt you can get. 

Beyond this, there are many other things to consider such as whether you plan to increase your usage significantly in the future. But since utilities don’t want you to be an energy producer they won’t actually allow for more solar than your historical needs indicate… unless you plan to buy an electric vehicle. These are things you should discuss more in detail with your qualified installer.

2. My roof is perfect for solar…right?

In my blog piece “Roofing Reality Check”, I outlined the main things to consider when you examine your roof’s potential. Here are the highlights:

You could put solar here,
but it will cost you!

Space: First and foremost, to be a good solar candidate you must have adequate obstruction-free space for rows or columns of solar panels facing South, West, or East. The solar array must be three feet from any roof ridge or rake, and 18 inches from valleys to satisfy Fire Marshall guidelines. In addition, most panels are about the same size…roughly 65 inches by 40 inches. An average home in SoCal needs between 15-20 panels to offset their energy needs. This means that triangular spaces and roofs with many small faces are not going to work well for solar, but big open spaces with right angles are perfect. 

Pitch and Height: Labor costs go up when installing on more difficult-to-reach roof spaces. Second story and steeply pitched roofs both increase the overall cost due to the time and effort required to keep crews safe. If you have a very steep roof solar isn’t necessarily impossible, but it will affect the bottom line, and some installers may not feel comfortable at all depending on just how steep. If it looks like an Appalachian incline more than a Rocky Mountain then you should be safe. But if we’re talking summit of Mount Everest, you may have a harder time finding a competent installer who doesn’t run when he sees the pitch. 

Roofing Materials: The best roofing material for solar is composite shingles. Developments have been made to safely attach solar panels to metal and tile roofs but the cost for the racking attachments and labor are frequently higher. Run on Sun prefers to remove tile where the array will go, re-roof with composite shingles, install the solar, and backfill with remaining tiles. This incurs a re-roofing cost but is the safest way to avoid roof leaks and ensure safe attachment of the array to the rafters.

3. Solar’s arch nemesis…shade.

One of the first things an installer will do is take a quick look at a satellite image of your property to check for shade elements as well as the layout of your roof. A useful tool in the Los Angeles area is the LA Solar Map. This takes into account shading throughout the year and provides a handy report on your property’s viability for solar. It isn’t a perfect tool, however, so take a look around your property and note if there are any trees shading the roof spaces that you’ve identified as ideal for solar. Trees to the north would not pose a threat since solar will never be placed on a north-facing roof. But tall foliage to the south could negate any energy production value of a solar array. All may not be lost as microinverters, like the ones from Enphase that we feature on our projects, can do a lot to salvage a site plagued with shade. But even with this technology, 100% shaded areas are a non-starter. In addition to trees, note tall parapets on a flat roof, chimneys, satellite dishes, HVAC units, and second story walls which directly shade your ideal roof spaces.  

4. Can my electrical system handle it?

Center-fed panels, like this one, can be a problem for going solar.

This is something many people are uncomfortable with, but a quick glance at your main electrical service you can be very informative. First, find your main service. This should be located on an outside wall of your home with circular enclosed meter protruding out. Open up the main panel where you’ll find a column of breakers. The main breaker, the one with the largest number stamped on it, is either at the top or sometimes in the middle of the column of breakers. If it is in the middle, this is called a center-fed panel and you may need to upgrade your electrical service before going solar.

If you find yourself tripping breakers every time you turn on a hair dryer, that is also a sign you should upgrade your service. Even if you aren’t tripping, depending on the size of your home, if the main breaker is stamped with anything under 200 you may need a higher electrical service before going solar to avoid tripping in the future.

Next, take a look at the rest of the breakers. Does it look like the entire column is full? Sometimes there are rectangles in the metal face plate which can be punched out to add breakers when needed. If there is no space at all for a new breaker for solar, then you may need to upgrade your service. 

Unfortunately upgrading your service will add some cost. Ask your solar installer for their opinion but if any of the above rings true be prepared for this additional hurdle to sunshine power.

5. It’s all about the money…

The reality is, solar is an investment. While some companies may insist you can go solar for free, I would never count on getting something for nothing. We have outlined some of the myriad reasons we recommend avoiding zero-down solar leases in other posts like “Top 5 Reasons to Stay Away from that Solar Lease” and “The Perils of Solar Salesmen”. Frankly, the costs can more than double over time when you lease instead of purchase your system. 

So the last step to assess if you are a good candidate for solar is to assess your financial position. There are many low-interest solar loan options out there as well as property-assessed PACE financing, but in order to get the economic value of solar you need to be prepared to own the system outright. This way you can take the 30% federal tax credit and any additional rebates if available from your utility. 

To give you a ball-park idea of the cost for going solar in Run on Sun’s service area (LA Metro area) today, including design, labor, permit fees and the whole shebang, is roughly $4 to $5 per Watt. This means that an average house with a 5kW system will cost between $20,000 and $25,000 before rebates and incentives. Obviously the cost will be on the low end if you have a composite-shingle, single-story, low-pitched roof with no need for a service panel upgrade. Depending on your electric bills pre-solar, this investment can pencil out with a return in as early as year 5 or as late as year 10+. But deciding if the financial outlay is worth the long term investment is something you must assess before signing on the dotted line. 

 After going through the above steps you should have a solid idea of whether solar is right for your home or not. If you’ve determined its a go, the next step is to call your local installer and make sure they check all the same qualifiers and more. Now that you’re an expert on solar assessment 101 you can even suggest solar to any neighbors with homes that beg to be powered by the sun!

So, you are considering a solar power system for your home or business… and why not, given the myriad of social, environmental and economic benefits! But how do you know if your roof is a good candidate? This is one of the top questions to consider carefully before investing in solar. 

1. Do I have enough space?

The size of your solar system is dependent on your usage needs and the amount you want to offset. However, it is not uncommon to find homes and businesses which are “footprint-constrained” - meaning their system size is limited by the space available.

A few things to keep in mind as you look at your roof and ponder how big is big enough… First, while there are many different solar panels they are typically the same size. Run on Sun uses LG panels which are about 65 x 40 inches and can be placed in either a portrait or landscape layout. Panel energy ratings vary, 285-315 watt panels are currently available from LG. For an average home (5 kW) that means you would need around 16-18 panels to offset the bulk of your electricity.

Another limitation is that fire code requires three feet of clear space from all ridges. If you have an irregular shaped roof with many valleys and peaks it may make the layout very challenging. Given that the panels are rectangular and racking is mounted parallel to the roof, rectangular spaces are ideal. However, the 3-foot rule does not apply to uninhabited spaces such as garages and carports making them good options if your home lacks the perfect solar roof. 

2. What if my roof is shaded?

Shading from trees, tall buildings, chimneys, or even parapets on flat roofs can significantly degrade the energy output from solar panels. Sometimes all that needs to be done is a generous trimming of that tree that’s gotten a little out of control over the years. Other times it means you really won’t get your money’s worth out of a solar system. But, if the shade elements are few and only during a short time each day, your roof may still be a viable candidate.

If this is the case be sure to talk to your solar contractor about inverters. We have written a great deal about the advantages of “microinverters” in handling shaded roofs, particularly those made by Enphase Energy.  “String inverters” on the other hand would be a bad choice as the entire system would degrade when any single panel is shaded. 

3. Should I re-roof my house before adding a solar system?

This may be the most important and frequently overlooked question to consider when researching if solar is right for you. Part of what makes solar a great investment is the 25+ year lifetime of the system. But if you have to re-roof during that time there are added costs to remove and re-install the system. If you are planning to re-roof during the lifetime of your solar array be sure you select components, such as the racking system, from companies that…A. will still be around 15-25 years later, and B. will be able to provide compatible replacement parts when pieces are lost during removal and re-installation. Avoid newer companies testing out “state-of-the-art” racking systems and cheap companies banking on the solar boom alone.

For this reason we always ask owners the age of their roof. In southern California, a roof over ten years old should get a makeover before installing solar. If you are unsure of the condition, it is a good idea to have a professional roofer take a look and give you an expert opinion. Sometimes solar contractors can offer this as part of their free assessment. (Run on Sun works with a very reliable roofer who is happy to take a look at any roof in question!) If the roof still has some life left in it but not enough to outlast the solar system you could re-roof only the area where the solar array will cover and plan to do the rest later. An added benefit is that the solar panels will actually protect your roof from the elements, helping it to last longer.

Unfortunately, you will likely be able to find someone willing to put solar on your roof even if it isn’t a good candidate. But if they aren’t discussing the above issues with you, then red flags should be flying! To ensure you get the best investment possible, do your research, take a good long look at your roof, and discuss all of your concerns with your solar contractor.