Are Tesla Solar Panels the best solar panels in 2018?
Everyone knows that Tesla, and its enigmatic Chairman Elon Musk, are masters of the big announcement. Critics might argue that some of these announcements come before they have solved the engineering problems inherent in what they announce, or that these announcements are more attuned to corporate funding requirements than to the technical progress of a new product, but they are also forging a stellar reputation for solving these engineering issues quickly and delivering on their announcements with great new products.
The Tesla Energy division of the company has, since its merger with SolarCity (approved by shareholders in November 2016) become the largest installer of residential solar panels in the United States. This has come about mainly as a legacy of continuing the same SolarCity business as operated before the merger.
The SolarCity business did, and still does, sell third party brands of solar panels and so confusion exists in the market today about what you actually get when you buy Tesla Solar Panels.
However since this merger, Tesla has made some new product announcements in the solar space and so now consumers are not exactly sure what they are going to be offered when they contact Tesla and request solar quotes for their home. This article sets out what solar panels Tesla is actually selling as of January 2019 and what they are likely to offer you.
Does Tesla manufacture its own solar cells?
As of January 2019, Tesla does not manufacture its solar cells per se.
Tesla has furthered its partnership with international electronics giant Panasonic to create Tesla solar panels. The partnership is based around the inclusion of the highly regarded Panasonic HIT cells into Tesla’s solar panels. Panasonic is up there with Sunpower in terms of having the most efficient solar cells on the market.
The relationship between these two leading electronics brands started with the inclusion of Panasonic lithium-ion batteries in the Tesla range of electric vehicles at Tesla’s Gigafactory 1 located in Nevada.
So what do you mean when you refer to Tesla Solar panels?
Tesla solar panels, created by their partnership with Panasonic, are produced at a purpose-built factory in Southern Buffalo (Gigafactory 2). The factory covering 1.2 million SQ feet is slowly beginning to ramp up with over 500 people already cashing paychecks from the facility, mostly through the Panasonic module and cell production areas.
Production started in late Summer 2017, with Panasonic generating cells and panels. This factory will also be building Tesla's exciting solar roof tiles which are roofing shingles that replace conventional roofing material but also contain solar cells to generate electricity.
However, the thing to note is that if you call Tesla and ask for a quote to install solar panels for your home then chances are they won't quote you Tesla solar panels at all. This is why there is a lot of confusion in the market at the moment. They have announced the manufacture of their own solar panels and also the Tesla solar roof but neither of these products are what they routinely quote homeowners looking for solar panels.
When people contact Tesla for a quote for solar panels they are usually put in touch with a salesperson from the old SolarCity business and the SolarCity business always sold third-party modules. Over the years they have sold many different brands including Hyundai Heavy Industries solar panels and QCells Hanwha solar panels.
A friend of mine got a quote for solar from Tesla recently for his home in Denver.
The first quote he received from them didn’t provide any detail of what solar panels (or inverters) they were actually using for the quoted price. Just some solar generation expectations and finance terms. This is a pet hate of mine in the solar industry, solar companies being less than straightforward about the brands of products they are using.
I regard this as arrogant. I understand the commercial benefit for the solar company doing it (they can then fulfill the contract with the cheapest solar panels they can find and can easily change between solar panel brands if they are offered a good deal at the wholesale level) but this practice makes it very difficult for a consumer to compare value between two competing solar quotes.
He had to request further detail on components and to his surprise, the initial quote he received was not using Tesla solar panels, or the Tesla solar roof, it was using a Hanwha Q-Cells module.
Only after contacting them a third time, and specifically requesting the Tesla panels brand was he given an option of using the Solar City branded (Panasonic cell) module.
It will be an interesting outcome to see what kind of markup Tesla believes it can achieve through the branding of its own modules with slight tweaks with an existing product available through an already reputable manufacturer in Panasonic.
How much do Tesla solar panels cost?
This question could have two meanings. What price does Tesla/SolarCity charge for residential solar installations? In this case, my friend was quoted $3.20 per watt for the QCells and SolarEdge equipment, which was $19,200 before the 30% tax credit for a 6kw system, or around 13,440 after claiming the 30% tax credit.
What I find interesting is that when pressed they did quote him the Tesla branded Panasonic solar panels for the same cost, which is actually a really good deal, but you have to press them for the Panasonic solar panels because they make less margin on these compared to selling you a cheaper third-party brand of modules.
If you can get a 6kw solar system using the Tesla branded Panasonic solar panels, and SolarEdge optimizers and inverter, installed on your home for $3.20 per watt before the tax credit ($2.24 per watt after the tax credit)....fill your boots and buy it.
What are the advantages of Tesla Solar Panels over other solar panel brands?
The unique HIT cell structure used by Panasonic incorporates both crystalline and amorphous (thin film) technology into the cell to convert more of the suns energy into electricity compared to conventional crystalline cells.
Basically, with the added 2 thin layers of amorphous silicon that surround the crystalline silicon, there are more levels of ‘net’ to capture the energy, therefore resulting in the higher performance of these cells in comparison to standard crystalline cells on the market.
How efficient are Tesla Solar Panels?
The current panel on offer through Tesla has a very respectable 19.4% solar panel efficiency (in comparison to 22% achieved by SunPower, or 17% from most Chinese tier 1 producers).
However, the real world performance of the Tesla solar panels is improved because the HIT technology also allows the solar cells to have a market leading .258% temperature coefficient.
This means the panels power output falls only 0.258% for every degree Celsius above 25 degrees. This is very, very good and along with SunPower panels with a temperature coefficient of 0.29% is significantly better than the average brand of solar panels.
The Tesla panels will also include skirting, to hide all solar panel mounting hardware from the ground view to ensure seamless integration into the roofing material. The panels will also have a black appearance to ensure the panels remains as aesthetically pleasing as possible. Interestingly, the Solar City branded modules are coming with a 15-year product warranty (apparently superseded by the Tesla all inclusive 20-year warranty), in comparison to a 25-year product warranty provided by market leaders LG and SunPower.
This same cell will be incorporated in the revolutionary Tesla's solar roof tiles. These products are designed to replace the current existing roofing tiles with a combination of both energy producing Tesla roof tiles and decorative roof tiles (nonenergy producing). The breakdown of energy and nonenergy producing tiles is determined by your energy consumption at the home. The Tesla roof tiles come with an infinite structural warranty and 30-year power and weatherization warranty. The confidence in warranty is explained by Tesla’s claim that the Tesla roof tile is 3 times stronger than traditional roof tile products. The tiles themselves are made of tempered glass (the same glass on the face of solar panels) to allow the light through to the cells for energy generation. According to Tesla, the rollout of these products should have begun in early 2018 on employees homes, with the general public to follow.
This new venture of creating Tesla branded panels in a partnership will be rolled out through Tesla’s recently (2016) acquired SolarCity, now operating as a Tesla-branded nationwide residential installer. This new Tesla branded installer will be responsible for the installation of all Tesla systems inclusive of the new Tesla roof tile products. The transition from SolarCity to Tesla hasn’t been all smooth sailing with very noticeable downtown in the turnover of the energy business. Tesla has attributed this slowing to a shift in procedure from the traditional SolarCity door to door solar loan sales approach to a bottom line improving cash business.
Author: Andrew Sendy | Home Solar Journalist
Andy is deeply concerned about climate change but is also concerned about cost of living pressures on American families. He advocates for solar energy and solar battery storage only to the extent that they make financial sense for homeowners. He is not affiliated with any particular solar company in the United States.