Tesla Solar or SunPower – Which Is Best?

Tesla Solar or SunPower - Which Is Best?

Tesla Solar and Sunpower are two leaders in the global renewable energy market. Tesla is best known for offering luxury electric vehicles alongside solar roofs and other technologies, while Sunpower focuses on manufacturing photovoltaic cells and solar panels. Tesla Solar sources solar panels from other manufacturers, while Sunpower makes them.

Type:Efficiency:Rated Power:Warranty:Degradation: (years 2-25)
Tesla Solar (Hanwha 315)18.7%315W12/10 yearsLess than 0.54%
Sunpower (Sunpower 415)22.3%415W25 years0.25%

If you’re looking to invest in renewable energy and solar panel technology, read on to find out more about how these two leading powers suit your needs (plus discount codes for both companies at the end!).

What to Know About Tesla Solar

After starting as SolarCity before being acquired by Tesla in 2016, Tesla Solar is now the part of the company that deals directly with sourcing and using renewable energy, either to supply other Tesla products or to offer resources like solar roofs. The Tesla Solar Roof and Solar Panels also influence another of Tesla’s emerging technologies: the Powerwall.

Tesla Solar Roof

The Tesla Solar Roof is a project designed to power your home with clean energy. It includes two types of textured tiles made from tempered glass. The tiles are a combination of solar and non-solar tiles that look similar. If you purchase the Solar Roof project, the Tesla team will create a specific combination of these tiles tailor-made for your home or business.

Tesla Solar Panels

Tesla sources solar panels from the best that is available on the market and integrates them into the company’s continually evolving technology. In recent times, Hanwha products have frequently been used by Tesla, especially the Hanwha 315 Q-Cell panels.

When choosing solar panels to integrate into Tesla Solar, the company looks for options that look great while remaining unaffected by high temperatures. The chosen solar panels should also have as little degradation as possible during their usual lifespan of 25 years.

Tesla Inverter

The Tesla Inverter is an essential part of the Tesla Solar home system. The inverter uses Powerwall 2 technology to convert the DC solar power into AC power suitable for home use. The inverter is an excellent addition to the Tesla Solar Roof but can also be used with other types of solar panels.

The Tesla Inverter is controlled from the Tesla app, where you can set up the home solar system to your specifications. The Tesla app will also allow you to monitor energy levels, and the inverter will receive over-the-air updates.

The inverter integrates with Tesla Powerwall and comes in two versions, a 3.8kW one and a 7.6kW one.

Tesla Powerwall

The Tesla Powerwall is one of the company’s star products. It is a rechargeable lithium-ion home battery designed to power home solar systems like the Tesla Solar Roof. The Powerwall also stores energy during the day that will always be readily available when needed.

Solar power recharges the Powerwall every day, which will give you a constant flow of clean energy whenever you need it. Powerwall can also be used as a back-up in traditional-energy houses. If there are power outages, the Powerwall becomes the primary source of energy for the household.

Powerwall is compatible with some central air conditioners, particularly those with a variable speed. These types of units usually require two or more Powerwalls for back-up purposes. You can also use Powerwall with compatible well pumps that are rated 20A or under.

Does Tesla Offer Discounts on Solar?

Tesla solar panels are already the lowest price solar panels on the market, but are there any other ways to save money when ordering?

In short, the only way to get a discount on Tesla solar panels is by using an existing Tesla owners “referral link” when ordering your Tesla solar panels.

Tesla has did this same “referral program” concept with it’s vehicles and essentially it allows new customers to get a discount on their purchase by using an existing customers personal referral link.

In regards to Tesla solar discounts, using a Tesla referral link when ordering will save you $300 off solar panels or $500 off solar roof.

The referral discounts are typically only available for a limited time before Tesla stops offering the discount, so take advantage of the savings while you can.

tesla solar panel discount

What to Know about Sunpower

Sunpower has been in the business of solar technology since the 1970s and has since become one of the leading companies in developing renewable energy. It was named the number one provider for commercial direct solar solutions across the United States three years in a row.

Sunpower is known for its efficiency and evolved technology when it comes to solar panels and photovoltaic cells. It also offers complete solar systems and solar battery storage. Sunpower seeks a sustainable future and wishes to provide the technology that will lead there.

Sunpower Solar Panels

Sunpower has some of the highest wattage solar panels on the market that are designed for home use. It was also the first company to create 400W solar panels. These high-powered solar panels are part of the company’s A-Series selection, but there are several other series on offer:

  • P Series: This series is meant for commercial projects and uses the Sunpower shingle cells. It offers 19% efficiency and panels from 380 to 400W.
  • E Series: Using Maxeon cells, this series offers 20% efficiency in panels that are 320W, 327W, or 435W. This is a versatile series for all types of work.
  • X Series: The X Series also uses Maxeon cells, achieving 22.7% efficiency in panels up to 370W. A common choice for residential projects, especially those with space limits.
  • A Series: The popular A Series uses Gen 5 Maxeon cells with 22.3% efficiency and features the world’s first 400w panels.

Sunpower Solar Cells

Sunpower’s years of developing technology for renewable energy have led to one of its star products: the Maxeon quality solar cells. These cells allow solar panels to produce 60% more energy during their 25-year lifespan than traditional solar panels.

The Maxeon solar cells have a copper foundation that gives them strength and resilience. The pure silicon covering allows for smooth conversion, and the surface is designed to capture as much light as possible by keeping the design without the typical grid lines found in traditional panels.

The Sunpower solar cells aim to avoid the issues that lead to panels breaking down, like corrosion. At the moment, the Maxeon cells avoid 85% of the common issues that can cause cell failure. The Maxeon cells are more durable than most other options on the market through the materials and the technology used.

The Maxeon cells also contribute to the sleek and elegant look of the Sunpower solar panels that make them a great fit in any project.

Sunpower OneRoof

The Sunpower OneRoof is a complex roofing system that fully replaces tiles and integrates solar power technology. This system has a 25-year warranty and has a Class A fire rating. It is also two to three times faster to install than other available options. The system features built-in grounding and integrated panel clips that make it an excellent choice for new builds.

The OneRoof uses metal components coated with Kynar, which offers increased resistance and durability, no matter the weather. OneRoof is designed to integrate with the rest of the roof space seamlessly. The black panels’ elegant look doesn’t stand out in jarring ways, while still providing plenty of protection from the elements with individually sealed screws.

Sunpower Complete Systems

Sunpower also offers complete solar-powered systems that cater to homeowners and businesses. For homes, Sunpower combines the Equinox system with the SunVault Storage. The Sunpower Equinox is a complete solar home service with a minimalist design but plenty of power, especially when paired with the SunVault battery.

The SunVault Storage battery helps preserve energy and power your home. You can get up to three days of power back-up from one battery. It’s comprised of two separate elements, the Hub+ and the energy storage system. Together, these elements work to keep your energy levels optimal.

For businesses and public settings, Sunpower offers the Helix system, which is made to suit commercial-scale projects. Helix has some of the most efficient solar panels available on the market, and it works on seamlessly integrating a complete solar-powered package with the daily routines of organizations.

Comparing Tesla Solar and Sunpower

Tesla Solar and Sunpower provide some of the leading options and technology for renewable clean energy. The two offer various options that aim to change households and businesses and lead them into a more sustainable future.

Tesla Solar and Sunpower can be directly compared in terms of looks, pricing, efficiency, degradation and warranty options, and customer reviews. They differ primarily in the fact that Tesla gets solar panels from other manufacturers while Sunpower creates them.

For the purpose of comparing, we will provide data from Tesla Solar’s use of the Hanwha 315 solar panel and Sunpower’s use of the Sunpower 415.


The aesthetic value of solar systems has become one of the determining factors when it comes to choosing the most adequate option. Sunpower has eliminated the typical grid lines from its solar panels, leaving them with a sleek black design that stands out through its elegance. This lack of ‘wired’ style tiles has brought Sunpower many accolades.

The Tesla Solar makes use of the Hanwha 315 solar panels, which have a more traditional look, including the lines that create the ‘wired’ effect. This difference makes Sunpower look more visually appealing, making a big difference to potential buyers. The smooth black tiles offered by Sunpower can be easily integrated with other elements.

While not all buyers will rate appearances high on their list, it still has importance on the list of criteria, especially when considering other elements that must mix with the solar panels. The visual appeal of parts like the:

  • Solar cells
  • Frame
  • Back sheet of the panels

May make the difference when it comes to deciding one or the other system.

With Sunpower patenting the sleek black design with no lines, the company went a step further than the competition. Managing to keep the high level of functionality of the panels simultaneously has been a bonus. Tesla Solar aims to offer a robust design and does include all-black panels with minimal gaps, but it seems to be trailing behind Sunpower.


Tesla Solar has made it a goal to offer some of the most affordable renewable energy solutions on the market. It aims to stand out from the competition through its pricing and has already boasted that its products are one-third less expensive than immediate competitors in the industry.

Tesla Solar has so far managed to keep prices below average across its selection of products. An investment in the systems will depend on the required size: small will be $2.44 per watt, medium will be $1.95 per watt, with the large and extra-large options costing $1.93 and $1.84 per watt before tax.

Pricing for solar systems in the United States will vary depending on the state where the installation will take place. Other factors that influence this investment are size, financing options, solar panel cost, and applicable government incentives if any.

Sunpower currently offers its systems in a range from $3.2 per watt to $4.5. This company’s prices have also seen themselves reduced steadily since 2010. When it comes to solar panels, paying more can often lead to better results because you are investing in quality and long-term durability.

With solar systems, you are investing in the future and banking on a return on said investment too. The Sunpower panels offer a 40-year useful life. During that time, the panels’ price will have a considerable impact on the savings on your electricity bill while not losing their efficiency.

When deciding on the best solar system for you, it’s best to research the expected lifespan of the solar panels you’re considering as an option. The expected lifespan will have an impact on the rewards you will get from switching to this system.


The efficiency level of solar panels is what determines the power they have. Sunpower is the first company that created 400w panels, and the Sunpower 415 continues the trend of powerful options. The 415 watts in the Sunpower and the 315 watts in the Hanwha used by Tesla solar are “rated power” or the panels’ output in perfect conditions.

The Sunpower 415, as the name indicates, can produce more power than Tesla Solar’s option of the Hanwha 315. The rated power affects the efficiency rating of the solar panels. The efficiency is a quantity depicted in percentages that indicate how much sunlight the panels can convert into electricity that can be used.

The efficiency rating of the Sunpower 415 is 22.3% to 18.7% of the Hanwha 315. This indicates that the Sunpower is more efficient in producing usable energy and can create more power in less space. Fewer panels are necessary to create a sustainable electricity output for a household or a business. 


Solar panels all degrade during their lifespan, but with considerably different speeds. The degradation process refers to the loss of production efficiency that solar panels experience. This can be due to a chemical reaction light called Light-Induced Degradation, or to an expected deterioration caused by the passing of time.

Sunpower has eliminated the impact of Light-Induced Degradation in its products by creating a specific chemical compound that protects its solar panels. This indicates that Sunpower will produce more power at a more consistent rate than most of its competitors from the start of the process, remaining unaffected by the impact of light on the panels.

Tesla Solar’s Hanwha 315 panels have an expected minimum output of 85% rated power at the end of the warranty. The Sunpower 415 panels have an expected minimum output of 92% rated power. The maximum annual decline expected in the Hanwha from year 2 to 25 is less than 0.54%, while for the Sunpower it’s 0.25% during the same timeframe.

Lower degradation indicates higher power production through the years, which can have a significant impact on the savings on your electricity bill.


Warranty cover is an essential aspect of investing in solar panel systems. Ensuring you are covered to receive assistance for as long as possible is ideal, just in case anything affects the proper functioning of the solar panels.

When it comes to the Sunpower 415 solar panels, the warranty extends for 25 years for the panel, inverter, and racking. It also included ten years of monitoring. With Tesla Solar’s Hanwha 315 panels, the warranty extends to 12 years for the panel and ten years for the inverter, without including any monitoring.

Business Revenues

When it comes to revenues, some differences are reported while comparing the renewable energy products of these two companies. Sunpower is a smaller-scale company than Tesla, but its solar panels and technology have enjoyed consistent stability and increases in revenue through their ever-rising popularity.

Since taking over SolarCity in 2016 and transforming it into Tesla Solar, this part of the Tesla company has been trending lower every year, without meaningful gains. Sunpower’s push for cutting-edge technology has positively impacted its numbers, despite reductions in staff and scope.

When it comes to energy storage, Tesla Solar has reported higher margins, but customers and consultants seem more attracted to the stability and technology offered by Sunpower.


Tesla Solar and Sunpower are well-matched when it comes to the products they offer to promote a more sustainable present leading to a clean energy future. Both these companies have appealing technology and options for solar-powered systems. Through a consideration of various elements, Sunpower seems to edge ahead in this comparison through stability, consistency, and features, but that could change as Tesla invests more in its own technology.

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The articles here on ThatTeslaChannel.com are created by Greg, a Tesla vehicle and Tesla solar expert with nearly half a decade of hands-on experience. The information on this site is fact-checked and tested in-person to ensure the best possible level of accuracy.

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