How do solar modules make electricity?

Solar modules are semiconductor devices, with cells made up of silicon. The bottom part of the silicon is treated with a trace amount of one element, while the top part is treated with a trace amount of another chemical. The junction between the differently-treated parts of the silicon creates an electrical “downhill” for charge. When sunlight strikes the cell, direct current electricity is generated. Each cell is about 0.5 volts. These cells are connected together in series, for a higher voltage.

For a more detailed explanation, see this explainer.

What do inverters do?

Inverters take the DC electricity from solar modules or energy storage (batteries), and convert it to AC electricity that can be used in your home or business. Some inverters are designed to be connected to the utility grid, and send electricity to both your loads and the grid. Other inverters can be used when the grid is down. Some inverters both work with the grid, but can also function when the grid is down.

How can I use solar electricity in my home?

With a grid-connected solar electric system, as the system produces energy, it will first go to your electrical loads in your home or business. If there is extra electricity, it will be sent back to the utility grid to be used by your neighbors (and you’ll get a credit for energy you send to the grid). For more information on how energy flows with a solar electric system, see our infographic.

Does my solar work when the grid is down?

If your solar electric system has battery storage, your system may work when the grid is unavailable. Otherwise, your solar electric system shuts down when the grid goes down. This is for two reasons: First, to keep utility personnel safe, we don’t want to energize lines while the grid is down. Second, providing electricity for off-grid loads requires energy storage with current technology.

How do I get solar on my home or business?

We’d love to share more about your solar options! First, take a few minutes to learn about your path to solar, then contact us!

How much does solar cost for a 2,000 square foot house?

It’s impossible to know how much solar you need based on your house size. This is because electricity use varies widely, even in homes of similar size. Instead, we can size a solar electric system for use based on your hourly or monthly electricity use. This process includes getting as much data as we can about your energy use from your electric utility, then carefully using advanced modeling software to determine the best system for your priorities and budget.

How does solar save me money?

If you use solar electricity as it is generated, solar reduces the amount of electricity you purchase from your utility, saving you each month on your electric bill. If you produce more energy than you are using at any given time, that energy is sent back to the utility grid for a credit.

What are the solar tax credits?

For solar electric systems that you own, both a federal and state tax credit apply. For more details, visit our tax credits page.

Do solar leases or power purchase agreements (PPAs) make sense?

For most homeowners, no. Solar leases may save you a small amount of money each month, but most of the benefits of the system go to the financing company, not you. Instead, consider financing your system with an appropriate solar loan. For business owners and non-profits, PPAs or leases may make more sense, but each situation is unique.

What are my options for financing solar?

We recommend working with a local credit union to finance your solar electric system. We partner with Tucson Old Pueblo Credit Union. TOPCU provides great rates, quality local service, and is transparent about the cost of the loans. Some providers require solar installers to embed extra “dealer fees” in the installation costs, costing you more overall.

We also encourage our clients to explore other options such as a home-equity line of credit. We’ll do our best to steer you toward quality financing options, but we’re solar folks, not financing folks.

Does solar add to my home’s value?

Yes! Several studies have found that owned systems do increase the value of your home. For example, Zillow’s study found that for a median-value home, solar added 4.1% to the selling price.

Two studies from Berkeley Labs also show significant value from owned solar electric systems, Selling Into the Sun, and Appraising Into the Sun. For homeowners to gain this value when selling their homes, it’s important that sellers use a real estate agent who can effectively market the value of a solar electric system or other green features.

What solar panels should I choose?

We recommend choosing solar modules (also often called panels) from an established manufacturer with a strong track record of producing quality products. You’ll also want a financially stable company that can stand behind a 25-year warranty.

We exclusively install solar modules from LG Electronics. We appreciate their efficiency, quality, and commitment to local solar installers, as well as their bankable ability to support their warranties. For more information, see Our Partners and Suppliers.

How long do solar panels last?

Solar modules are typically warranted for 25 years, but high-quality modules are expected to last much longer. We’ve seen modules 35 years or older continue to produce meaningful energy. It’s normal for the power output to drop just a little over time, usually around 0.4-0.5% per year.

Why choose microinverters?

With microinverter systems, each solar module is paired with a microinverter, which converts DC to AC electricity. (In string inverter systems, modules are wired together in series for high voltage DC, then connected to one bigger string inverter).

Microinverters are designed to maximize your energy production, provide excellent system monitoring, and last for the long term. They also provide significant safety benefits. For more information, see Our Partners and Suppliers.

Does energy storage make sense?

Energy storage?—usually in batteries?—can make sense in specific cases, but not for most consumers. Energy storage can allow you to store energy on-site for use at night, or during cloudy periods. Many energy storage systems also provide backup power for when the grid goes down.

But these systems are expensive. It often costs much more than current utility rates to store energy in batteries. So if you’re interested in backup power, we encourage you to consider energy storage. But if you’re looking to save money, energy storage doesn’t make sense in southern Arizona. For more information, see our batteries page” and link to https://www.netzerosolar.net/Batteries.html

What are the warranties on Net Zero Solar’s installation?

Net Zero solar provides a ten-year warranty on the installation and operation of the solar electric systems we install. We also provide a five-year performance guarantee on solar electric system output.

Where do you install solar electric systems?

“We install solar in much of southern Arizona. This includes Tucson, Oro Valley, Catalina, Oracle, Saddlebrooke, Saddlebrooke Ranch, Marana, Picture Rocks, Mount Lemmon, Sahuarita, Green Valley, Rio Rico, Amado, Tubac, Tumacacori, Patagonia, Sonoita, Elgin, Sierra Vista, Hereford, Palominas, Vail, Benson, Mescal, Dragoon, Huachuca City, Whetstone, St David, and nearby areas. Feel free to contact us regarding your specific project location.

How long will my solar installation take?

Typical residential solar installations take 1-4 days. Ground mount systems take longer. We’ll let you know the details before your installation is scheduled.

How soon can I turn on my solar electric system?

You can turn on your solar electric system after both your local building department and your electrical utility have inspected and approved your solar electric system.

Who will be installing my solar electric system from Net Zero Solar?

Your solar electric system will be installed by our team--we don’t use subcontractors. Want to know more? Visit Meet the Team.

Why do I need to upgrade my electrical panel?

You may need to upgrade your panel because the current panel is unsafe, to allow connection of a larger solar electric system, to add a subpanel to fit solar breakers, or to allow installation of energy storage. For a detailed discussion, read Why Do I Need to Upgrade or Replace My Electric Panel?

How do I turn on my solar electric system?

Turning on your solar electric system involves turning on several circuit breakers, plus a disconnect. For details, see How Do I Turn On My Solar Electric System.

How do I reconnect my monitoring to the internet?

Follow these helpful step-by-step instructions from Enphase Energy.

What happens if the grid goes down? Will I be able to power my loads?

If your solar electric system has battery storage, your system may work when the grid is unavailable. Otherwise, your solar electric system shuts down when the grid goes down. This is for two reasons: First, to keep utility personnel safe, we don’t want to energize lines while the grid is down. Second, providing electricity for off-grid loads requires energy storage with current technology.

Why am I getting a power bill?

Everyone who is connected to the utility grid will pay for basic service charges, taxes, and fees. Depending on the utility, this will be between $15-30 each month. In addition, you’ll be billed for any energy that comes from the grid. This amount may be offset by bill credits from energy exported to the grid.

Most customers with solar electric system under export rates should expect to have at least some bill during summer months. Customers grandfathered under net metering often still have one or two significant bills each summer, depending on their specific energy use.

Why does my bill say I’ve only sent a small amount of energy to the grid?

If you use a lot of energy while your solar is producing energy, that energy will go directly to your loads. That won’t be reflected on your utility bill, but that self-generation will save you the most money. For more information, see our infographics Where Does Your Energy Flow with Solar? and How Does My Solar Electric System Work with Export Rates?

What maintenance do I need to do for my solar electric system?

Very little maintenance is required. In addition to a free one-year checkup provided by Net Zero Solar, we recommend a visual inspection of the system each year. If installed on a built-up roof, continue regular maintenance of the roof, including new roof coating over the solar flashings.

Generally, cleaning of solar modules is not necessary, but if you live in a very dusty area, it may be necessary to hire someone to clean them occasionally. See more information from SilFab Solar.

What happens if I need to replace my roof?

If you need major roof repairs, you will need to have your solar electric system removed, and reinstalled once the roof work is done. To maintain your ten-year warranty from Net Zero Solar, you will need to hire us to do this work.

Because of the significant labor involved, removing and reinstalling your solar electric system can cost several thousand dollars. So if you’re thinking of installing solar and you expect roof work will need to be done within the next five years, we recommend having that work done before your solar installation.

In any case, it’s best to coordinate solar installation or removal and reinstall with your roofer for best results.

What do I do if MyEnlighten monitoring says a microinverter isn’t working?

As with any electronic device, communication glitches sometimes happen, and can often fix themselves. But if after 24 hours MyEnlighten is still showing a problem with a microinverter, contact us, and we’ll take it from there.

How does energy storage work?

Current energy storage are lithium ion or lead acid batteries. Both battery types store electrical energy using a chemical reaction. When the sun shines, the batteries are charged. This energy can be used at night, or for some systems, if the power goes out. For more information, see our Batteries page.

Lithium ion batteries require virtually no maintenance. Lead acid batteries may require maintenance.

Will energy storage save me money?

For customers in southern Arizona, energy storage will not save you money. It costs more to store the energy in batteries than that energy is worth. However, energy storage can provide independence by either keeping the energy on-site for later use, or for some systems, providing backup power when the grid is down.

Can I run my air conditioner or heater if the grid is down with energy storage?

Running air conditioners, electric heat, electric water heaters, electric stoves, or other other large loads is usually too expensive with energy storage. Lights, refrigerators, electronics, swamp coolers, small window air conditioners, some mini-splits, gas furnaces, and other similar loads are possible to run.

Does Net Zero Solar service or repair existing solar electric systems, even if NZS didn’t install it?

At this time (early 2023), we do not have capacity to provide service for systems we did not install.

In the past, workload permitting, Net Zero Solar serviced grid-tie solar electric systems with Enphase Energy microinverters, that don’t include energy storage. Before we provide any service or repair (such as replacing microinverters), we must do a complete evaluation of the system, and the system must be brought up to current safety and code standards, and to Net Zero Solar standards at the discretion of the NZS evaluator.

What are your service rates?

Note that as of early 2023, we do not typically have capacity to provide service to systems that we did not install.

Service rates and trip charges: $110/hour, with a 1-hour minimum.
For systems not installed by Net Zero solar, a trip charge of:
In Tucson area (includes Oro Valley, Marana, Vail, Green Valley, & Sahuarita): $50.00
Outside of Tucson: $150.00

What do you charge to evaluate an existing system before providing service?

Note that as of early 2023, we do not typically have capacity to provide service to systems that we did not install.

$250.00 in Tucson area (includes Oro Valley, Marana, Vail, Green Valley, & Sahuarita)

$350.00 outside Tucson

Evaluation charge includes a written report detailing any required repairs, along with a bid for those repairs.

Do you charge for service of systems that Net Zero Solar installed?

Net Zero Solar’s ten-year warranty covers all service costs. After ten years, Net Zero Solar may charge a discounted service rate, if these costs are not covered by the equipment manufacturer. This discounted rate is 50% of the standard labor rate, or currently, $55/hour.

Do you install off-grid solar electric systems?

Although we have installed off-grid solar electric systems in the past, we no longer have the capacity to do so, unfortunately. However, we do install battery backup for grid-connected solar electric systems.

Can I go off-grid in my current home?

Although it is technically possible to go off-grid in an existing grid-connected home, it is not advisable. Taking a typical home off-grid can cost $50,000-$75,000. Instead, you’ll want to aggressively pursue energy efficiency measures first, then consider adding energy storage. It rarely makes sense to disconnect from the grid altogether, from both economic and environmental standpoints.

Do you install solar electric systems for RVs, boats, landscape lighting, or small cabins?

We don’t install on RVs, boats, landscape lighting, or small cabins. For these applications, consider commercial products from Goal Zero, kit systems from AltEStore, or options from other providers.