Are Solar Electric Cars the Future? An Exclusive Interview with Sono Motors

Are Solar Electric Cars the Future? An Exclusive Interview with Sono Motors


Solar Electric Cars, Solar Mobility or Vehicle Integrated Photovoltaic (VIPV) is one of the hot trends of Solar Energy and PV technology, and we will hear more & more onwards as we are moving on with the green transition. Being a part of eMobility & Electric Cars revolution in the car industry, Solar Mobility has some distinct extra features such as power generation, independency and some other brand-new features that frontliners in this field are bringing to the market.

The term might be new to many of us, but the truth is that they have a history that goes back to 1955. In this article, we have dived deep into the topic of Solar Electric Cars & VIPV with one of the frontiers of this technology, with an exclusive interview in September 2021 with Lars Loehle Sono Motors Director Of Business Development and Public Affairs and Julia Mederle. Sono Motors is one of the front liners of Solar Mobility and they have come up with the first & only affordable solar electric car that is actually on the way to production in 2023 and can charge up to 30 km in a day.

History of Sono Motors

SE: Let’s start with how things got started. We in Solar Edition have been following Sono Motors and Sion at least since 2018 when we started & it has been a very interesting journey. If we recall correctly first, there was a plan to produce it in Germany then it moved to Sweden. Tell us all about it.

SonoMotors: Exactly. Maybe coming back to the roots of the company. So 2012, Laurin and Jona, two out of three founders actually, both as the CEOs of Sono Motors today. They took an old vehicle with a combustion engine and put an electric motor in it and put solar panels on it and that was the very first proof of concept of a solar electric vehicle. So it took them years to build and make it fully functional and in 2016 they decided to found the company. Almost a 6-year-old journey and regarding your question of production, yes we are planning to produce with the National Electric Vehicle Swedish (NEVS), the old SAAB factory. Rather close to you guys in Norway. This has used rather a huge production plan and staff are most quite big and we found a good box for the production line only to build-up fast over there and an additional very important factor for us of course is that they produce with 100% renewable energy in line with our values.

The Sion – Set To Be The First Affordable Solar EV I Sono Motors

SE: Wow, renewable energy for the production line as well, great bonus. Is that thought also about parts production as well?

SonoMotors: Exactly, exactly. That’s one of the main factors of our company. In every decision we take we think about sustainability as well and the property is not the highest value altogether.

SE: When will the production start & what production volume are we expecting?

SonoMotors: The serious production will start in the first half of 2023, that is the plan. We plan to produce 257,000 vehicles over the lifetime. Over Lifetime is usually roughly 7 or 8 years.

SE: We are now excited, 2023 is JUST one year ahead. When are you planning to enter the Norwegian market?

SonoMotors: You can already reserve a Sion in Norway and among the 16.000 reservations we also have a few in Norway. Delivery is planned for next year. Reservations are open for all European left-hand driving countries. There is a map of Sion’s reservation online showing an overview of the pre-ordered Sion, the solar electric car. We have already had a reservation from Norway. So currently Sion is open for ordering no matter the location. The only thing is that we are focused on the left-hand drive market which is actually Norway also a part of.

Sono Motors, preorder Sion
SION can be preordered NOW

Economical Aspect

SE: Will the Sion be presented in a single model?

SonoMotors: There will be one variant only with black color. Everything inside is black also. There is a small option to have a tow bar, which can be used to drag something or carry your bike.

Sono Motors & Lightyear One

SE: What are the distinct features of Sion which make it different from other rivals such as Lightyear One or Prius?

SonoMotors: First of all, we wouldn’t call Lightyear a rival. We are working hand-in-hand actually together with them so they are rather colleagues than rivals in our eyes. So I have to say the same vision and missions bring them to the Solar EV market and of course in different categories, as we promote an affordable solar electric vehicle for our customers. We have a polymer-based solution which no one else currently has in the market and also distinct features like “vehicle to grid” (V2G), “vehicle to vehicle” and “vehicle to device”, which we offer included in Sion.

Solar Mobility evolution_sonoMotors Interview
Evolution of VIPV in Sono Motors from 2017 to 2022

Another distinct feature is that we deliver the car with “community car-sharing feature” and so you can share your solar electric car with friends, community, and the public. Additionally, you can actually sell the electricity to other cars and to grid with car sharing. It is also important to mention here that our goal is not to sell as many cars as possible, but we actually want to help the transition to a future with fewer cars on the streets and broadening the share’s cars services.

SE: Interesting that you mention sharing services here as a focus area for Sono Motors and Sion as a product. Can you elaborate more and explain what opportunities come with owning a Sion?

SonoMotors: So when you have a Sion, all the sharing services and interfacing are already there. We provide an App and we already run some pilot projects. The idea is that you can share your car peer to peer with others. You can also sell your energy to others. For example, let’s say, you are on vacation for two weeks, you could either share your solar electric car completely or only sell the energy stored in the car battery, as it is self-charging. So there are various opportunities for you as an end-user and owner of Sion.

SE: So it means, you can park your Sion in the sun and connect it to the Grid. As long as you choose in the app, the produced energy transits from the car back to the grid, right?

SonoMotors: Exactly and regarding vehicle to grid topic, we are now having our first project with the city of Utrecht, in the Netherlands. We are delivering 100 solar electric cars to them and it is actually a huge project, I would say the biggest in the world for vehicle to grid application. The goal there is to stabilize the grid with our science and if you think of it, it is like a big storage system for the transition to renewable decentralized energy and that‘s a piece of the puzzle.

SE: What is out there as an issue to overcome to take the Solar EVs sales to the next level?

SonoMotors: This is part of the work that we are doing with ASAM, with the alliance. So, first of all, we need to raise awareness and educate the industry and the politicians about this new technology, which actually helps tackle some hurdles in the infrastructure and public for cars. I am not sure how this is in Norway, probably better. But in Germany, we are still facing troubles with the charging infrastructure and for us it is really about educating, raising awareness, and with that I think we can actually establish a new industry in Europe for vehicles integrated photovoltaics.

Why Solar? Solar Mobility evolution_sonoMotors Interview
Why Solar? Why Solar Mobility?

SE: Norway maybe is quite unique when it comes to EV infrastructure, but it is totally understandable as in my trip to South Korea, It was not easy to charge the cars unless you owned a personal plug-in or charger or you were lucky that the nearest gas station has already been upgraded with rapid chargers (situation is rapidly changing). In that way, it is almost impossible to own an EV.

SonoMotors: Yeah, exactly. That is of course one of the reasons why we took solar into a car because actually that produces energy that consumes the needed energy at the end with less need for new infrastructure.

SE: Is it still the same capacity that it charges 30 kilometers per a day?

SonoMotors: It is 112 kilometers in average per week based in Munich. So that is an average over the year between January to December. So I think I have up to 35 kilometers on peak days roughly in Munich. Of course it always depends on the location if you are further south with longer days with sun, the case is getting better and better.

SE: You mentioned the obstacles that are in the sales of Solar EVs, due to cultural and infrastructural obstacles you face. Can you please elaborate?

SonoMotors: Yes of course, from a solar technology perspective, we don’t face obstacles on the way. We actually see huge interest in Sion itself. Another issue we face is a lack of awareness, especially on the regulation side from politicians in the EU. For example, we already had an event in Brussel a couple of weeks back together with the alliance to get in touch with politicians directly and raise awareness in terms of solar mobility opportunities. Also from a business case perspective, as politicians need to invest a considerable amount of funds for the transition from combustion engines to EVs.

SE: We hear awareness increase among politicians and decision-makers, are you fighting the same battle that renewable energy producers are fighting against conventional subsidies and incentives for fossil fuel businesses?

SonoMotors: Not exactly, but somehow we are fighting a similar battle. We are the first movers together with Lightyear in the passenger vehicle market and solar mobility (solar electric cars). What is missing in EU directives is that topics like solar mobility are not considered. We believe existing subsidies for renewables should also apply for solar mobility. Currently, this is missing and even for plans in near future this has not been considered, that’s why we are bringing up the topic of increasing awareness among politicians and decision-makers as there are huge opportunities there for Europe. Even when it comes to normal people, a lot of them have not heard of solar mobility and available options.

SE: Correct. You also mentioned your other partners like Lightyear One. You are also in this mobility alliance. Can you tell us more about it?

SonoMotors: The alliance, ASAM, is basically where there would be different research institutes like TNO, Fraunhofer ISE, and Lightyear. And we are actually trying to put awareness to the effect of solar mobility. This is a very promising industry and a very promising trend (interesting article on Solar Mobility from Sono Motors blog). I think all the partners are on the website and so the most well-known research institute TNO is in the Netherlands. They are really expert and focused on solar electric cars (solar mobility) as well as Fraunhofer ISE in Freiburg.

SE: Talking about the range that the sun can charge up the car daily, how would that help commuters? Like in Norway, I personally drive around 10 km to work and back home. How is it for most people? Is it just saving some on the electricity bill or actually can they count on a free ride based on statistics as I can do with my 10km?

SonoMotors: Yes definitely. We actually developed Sion to help commuters to move by the sun at the end. So in Germany, the average for commuters distance in urban areas is 16 kilometers per day and that is what we have achieved throughout a year on average and sometimes of course is more in summer and less in winter. On average that means 112 km a week, depending on regional weather conditions. In January you are being moved only by the sun 100 km per week and that is quite a bit for traditional commuters I think the numbers apply more or less throughout Europe, without knowing exact numbers, also considering the fact that sunnier regions will have higher numbers.

In Germany what we see and you also mentioned is that we can reduce the charging cycles up to four times with the solar integration (detailed calculations by Sono Motors in the link). Compared to other similar EVs with the same segments, size, and consumption of energy. That’s not 100% independent, but it helps you to save money, is more comfortable, and is more eco-friendly.

The Average Commuter Calculations by Sono Motors

SE: Exactly. It is four times that you mentioned, is it per week?

SonoMotors: No, it is in general up to four times less cycling. That of course depends on your driving profile. As you said, if you drive 100 kilometers per day, you have to charge more often than other commuters.

SE: What group of customers are your sales target and which countries have you already started your sales? When do you come to Norway? We are eager to test Sion !!!

SonoMotors: We basically focus currently on the left-hand drive in Europe and you can pre-order / reserve a Sion any time. Production is planned to start in the first half of 2023.

Technical Aspect

SE: Does Sono Motors utilize any special concentrated solar irradiance layer in its solar cells to enhance power output of solar cells?

SonoMotors: We use a special material stack that we have been testing for years. We put lots of engineering effort into that and with regards to efficiency, what you get out of solar cells is one thing, but the car electric system is a big part of it as well. There is a lot of effort needed to optimize the system in terms of how to behave with shading and light you receive on which side of the vehicle to optimize that.
This is really our core competence and the PV stack material that we developed putting in that together with our so-called MCU. The MCU we developed is a controlled unit for MPPTs which brings together multi-channels and that is our core competence in PV plus the electric integration.

SE: Is integrated or tailored solar cell architecture used in Sion proprietary to Sono Motors or is it a generic technology, such as thin-film?

SonoMotors: No, we use polymers. We have a polymer as a scratch for our system’s outer layer. Solar cells are of course in the body panels itself and basically, this whole technology and manufacturing process is patented by Sono Motors. Our photovoltaic (PV) integration is patented, and our dent-resistant polymer outer skin is the only non-glass PV integration of its kind. This allows the panels to be seamlessly integrated into the bodywork and reduces the cost of future repairs. Due to a unique patented manufacturing process of the parts, our technology is lighter, more energy-efficient, and cost-efficient than any other solar application on the market. Our solar technology also has the potential to be licensed to other industries.If you Google it. You will find it also the public patent from that one.

SE: Next one is a maintenance question that potential Sion buyers would have dealing with new state-of-the-art technology. Suppose a part of a door is severely damaged in an accident, especially in areas where solar cells have been integrated, is it possible to repair damage without completely replacing that door or not?

SonoMotors: Good question and something we hear frequently from customers as well. To start with, the polymer is more robust than the usual paint of the car, so it’s good to mention that we don’t paint the car, it is purely black polymer. Of course, on the cell level it is transparent and this of course helps in all scratch resistance better than basically paint and more robust.

On the other hand, if one single cell is defective, it does not affect the performance of whole module in our case. On top of that, our whole concept is that we don’t have a paint shop which is very costly for traditional OEMs and also in the repairing process. In that sense if you have a severe accident that you definitely have to change the side door then we expect that our components of doors are not more expensive than traditional painted doors. Of course, we have an additional cost on the solar technology side but less cost on paint.

SE: If a cell breaks down, do you need to change the module?

SonoMotors: No. It really depends on what the loss level. If only one cell is broken in one module, and let’s say that the efficiency drops from 100% to 97% then you might just consider leaving like that, but of course, if you like to have a whole module, loss of dysfunctional to 10% or zero at the end you, of course, need to replace it yeah.

SE: Do you have any monitoring application inside the car that actually detects faults in solar cells? As we see this issue in panels in solar PV power generation that for example drones are used to detect dead cells.

SonoMotors: We are developing a diagnostic system for this purpose. A tool to exactly specify which cells are not working and in which areas of the car.

SE: How is this shading handled in Solar EVs and especially Sion?

SonoMotors: First of all we developed the Sion as a solar electric vehicle for the masses, having a maximum output of solar reach in mind. We are optimizing everything for that purpose – from the cell level to a multi-channel electrical integration – this way we optimize also towards its ability to perform in different environments such as partial shading when using it in city for example.

SE: Interesting. When I think about it like solar arrays in solar installations, losing one panel does not mean losing one panel in conventional PV installations. It also means that it would bring down a number of the panels because they have to have the same voltage. So that interconnection of the cells is also very important. Has that been considered?

SonoMotors: Exactly, Sure. That is part of the MCU- it’s a multichannel system that allows us to optimize the energy output even if you have a failure on the cell level work. The controlled unit development I mean for that you need different channels basically for MPPTs. Different areas then you don’t have losses everywhere if you have a shade on one module. That is very essential to push the efficiency of the whole module.

SE: WallBox, how long does it take the wallbox charging completely one Sion?

SonoMotors: The wallbox we offer is a bidirectional wallbox with a unique technology that enables us to offer the first cost-effective wallbox for bidirectional charging.
Bidirectional DC wallboxes available on the market up to this point are relatively more expensive, as they contain an inverter to convert the direct current from the vehicle’s battery into alternating current, in order to feed it back into the house. By integrating the inverter into the Sion’s on board charger (OBC), we can massively reduce the cost of the wallbox. This makes bidirectional charging affordable and at the same time enables us to make our contribution to a future with 100% renewable energy.
The Sono wallbox is capable of fully charging the Sion’s 54 kWh LFP battery in up to 5 hours, making it perfect for overnight charging and ensuring a range of up to 305 km. In addition, the Sion can be charged at fast-charging stations at a speed of up to 75 kW (DC) via the integrated CCS interface, i.e. to a charge level of 80% in around 35 minutes.

Charging your Sion will be possible with 11kW (AC).Wallbox is ??? kilowatts with AC and is different from classical DC Wallboxes. It would roughly need 5 hours or up to 5 hours to charge fully with that Wallbox.

SE: How much is the difference in the time that takes to charge by the Wallbox and conventional plug-in chargers in the market?

SonoMotors: I mean there are so many different models out there, so it is tough to say but what is special for us, our Wallbox is AC and it is a bidirectional Wallbox so you can actually provide energy through it. Classical wallboxes don’t provide that and if they do, they are very expensive so we are targeting cost-efficiency AC wallbox ourthere bidirectional wallbox charging. By the classical household sockets, you need roughly 11 hours so overnight basically. More information about WallBox here.

Bidirectional Sono Wallbox

SE: Can you tell us more about the community car-sharing services which is a joint V2G project in the city of Utrecht, Netherlands.

SonoMotors: I can roughly skim through it. There are 500 bidirectional charging stations in the city of Utrecht or there will be. For the project, we deliver 100 Sions over there and together with them we are basically trying to stabilize the grid if there is too much wind power generation, these could partially be stored in Sions. If there are not enough renewables for the city of Utrecht, they can use Sions as the stabilizer for the grid at the end. Of course, the sharing will be on the car side as well.
I am not 100% informed if this is community-based or totally public, but usually you can use our app to share the cars as well. More information about V2G project in Utrecht here.

SE: The topic of Vehicle to Grid is very interesting & practical projects are something very unique right now that you can not find everywhere.

SonoMotors: Yes, exactly. This is another topic that we need to raise awareness among politicians, investors and the public crowd about opportunities in Vehicle to Grid, Solar Mobility & Sion. Because here we are not only talking about changing from combustion engines to EVs. Here to solve the issues in hand, we can cooperate with renewable energy producers in the green transition and help them with issues on their hands on the way. That’s why vehicle to grid is actually a huge opportunity to change cars from consumers to decentralized storage solutions.

Another perspective of this is for private owners. With buying a Sion, you would own a battery of 54 kilowatts/hour. In the case of having Solar Panels on your own roof, you basically don’t have to buy your own expeansive storage system. These all together make the case much more economical in that sense.

SE: Talking about the V2G and potentials there, have you considered bigger batteries that are becoming the norm today, to increase this impact? We of course understand the hassle with that considering being first movers in solar mobility.

SonoMotors: Sure. What you have to see if we connect all the Sions at the end for utter life-cycle over a quarter a million Sions would be out there with over 50 KWh battery. It ends up quickly to a big number to big potentials. When it comes to increasing the battery, it is always about economics. We considered different battery sizes and asked ourselves various questions. Which cell technology is simultaneously highly efficient, resource-friendly and safe? What is the minimum range the Sion should have? What are our Community members average demands? After intense discussion, we came to the conclusion that a capacity of 54 kWh in combination with the new cell technology is just right for the Sion better battery size.

Battery Price, Bloomberg
LI-ION Battery PACK Price, 2010 – 2020

SE: This is a really exciting development, could you please tell us more about this?

SonoMotors: Our patented Sono Solar Technology is the only polymer-based solution in the market. The cost-efficient polymer exterior replaces paint and sheet metal exteriors, it is more flexible and lighter than regular PV modules and we are able to form a range of complex geometries across applications. We integrate solar to the car body panels during an injection molding process, allowing a seamless integration of the PV function into the car body panels.
This patented technology we have engineered internally and we are bringing to reality with our partners.
For our ViPV and VaPV licensing business we use a number of different solutions with various solar module recipes as well as mounting solutions (clamping, glueing, integrating), depending on the customers needs. Including power electronics and information service, as well as installation. This way we guarantee a much more seamless integration that is lightweight and highly efficient.

SE: Is it only applicable to new cars or are you looking into upgrading existing vehicles as well as a business model?

SonoMotors: For commercial vehicles, we are also working on retrofit solutions.

SE: Any ongoing pilot projects on these proposed models?

SonoMotors: We just showcased a new prototype project together with Ari Motors, a Light Electric vehicle manufacturer at the Intersolar exhibition in Munich. We have already signed over ten LOIs and three commercial contracts exploring strategic use cases with companies such as MAN, Easymile and Wallaby Boats. More information on this project in link here.

VIPV Applications, Solar Mobility evolution_sonoMotors Interview
VIPV B2B Applications beyond passenger cars, by SonoMotors


SE: Is there any revolutionary development happening in VIPV and Integrated Solar cells world? What do you see as the next step that the technology has to overcome to take this concept to the next level?

SonoMotors: There are a number of trends supporting and pushing the need for solar mobility. For years we are experiencing a significant price drop in high efficient solar cells as well as batteries while at the same time efficiency for Solar cells is improving constantly. This way using PV technology for mobility and transportation is making more and more sense and we are seeing that also in the interest from the transportation industry in our technology as well as more and more OEMs working on different ViPV solutions.

Apart from that, turning passive areas into active ones and producing local energy wherever you need it, is a crucial part of making the energy transition possible and an important goal for us.

SE: What types of solutions have you envisioned for extending the driving range of Sion including using another high-efficiency solar cell tech/architecture or more massive lithium-ion capacity than that has been used?

SonoMotors: we are using high-efficiency monocrystalline back contact cells for the Sion but of course are always analyzing the market and testing new PV suppliers and cells. Also our own power electronics, the MCU works as a multichannel system to enhance power output to a maximum. Due to the feedback from our community we also integrated a larger battery and upgraded to a 54 kWh LFP battery.

SE: Is there a self-driving option item for Sion in the future?

SonoMotors: We do believe that self-driving cars are an interesting field for the future of mobility, but our development focuses on the Sion as is and our Solar integration at the moment. ADAS features that are required from 2023 upwards we are including in the Sion and will announce at a later date more details.
SE: What is your vision for 2050 and what is your imagination about EV and solar EV at that time when almost the largest portion of energy consumption of buildings will be supplied from renewable energy?

FULLY CHARGED, The cheap solar-powered car you might NEVER need to charge | SONO SION

SonoMotors: Our vision is “solar on every vehicle”, so we, therefore, want to see a major push in solar mobility. On the way to 100% renewable energy, Vehicle 2 Grid (V2G) will play a massive role in storing a large amount of renewable energy. Instead of switching wind turbines off in times of energy surplus, the excess energy could temporarily be stored in the vehicle’s battery. In addition, peak loads can be cushioned by a network of electric cars. The legal requirements still have to be met. And last but not least we want to increase the use of personal cars through community car sharing.

Did you know?

Solar Edition publishes this trending article with new top 10 PV solar panels monthly since 2019. We publish two Top 10 Solar Panels lists, 

Questioner: Shahab Moghadam

Editor: Shahab Moghadam & Hesam-Edin Hayati Soloot

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