Sono Motors Sion solar production is underwhelming

Sono Motors Sion charging a Tesla Model S
Sono Motors Sion charging a Tesla Model S

Sono Motors Sion is an unique electric concept car that is covered by “more than 248 solar cells”. According to the advertised specs, at peak performance, all these solar cells should be able to provide up to 1,2 kW.


However, in the real world we shouldn’t expect the solar production peak to be much higher than 400 W, even on a sunny day.


Sono Motors Sion solar production is underwhelming

Sono Motors Sion solar production is underwhelming


As expected, the large solar panel on the roof produces more electricity alone than all the other four combined.

I think that in electric cars, solar panels only make sense when placed on the top. Solar panels surrounding the vehicle only add complexity and costs without giving much in return.

Moreover, we don’t know yet if the solar panels on the sides compromise crash tests.


Nonetheless, the Sono Motors Sion has nice specs.



  • Price: 25.500 euros
  • Battery: 35 kWh
  • Drivetrain: 120 kW Motor
  • Torque: 270 Nm
  • Max. speed: 140 km/h
  • Charging: CCS: 30 Min. – Type 2: 3,5 h – Schuko: 13 h
  • Range: 255 km according to WLTP standard
  • Solar range: up to 245 km/week
  • Trunk volume: 650 L
  • Tow bar: 750 kg


You can even use the Sion to charge other electric cars, which is pretty awesome.


Anyway, in my opinion, one electric concept car that implemented solar panels correctly was the Pininfarina B0. It’s a shame that an electric car like this never made into mass production. The Bollorรฉ Bluecar that went into production was basically an uglier 3-door version and without solar panels.


Pininfarina B0

Pininfarina B0


In some situations, a good 300 W solar panel roof in an electric car could add around 2 kWh to the battery per day and would be enough to drive an extra 10-15 km.

Situations like you go to work and leave your electric car parked for 10 hours near the train station.


Fortunately, the Hyundai IONIQ 5 has a solar panel roof and if the concept proves its value, more automakers will be tempted to introduce solar panels in their electric cars. The upcoming all-electric SUV Toyota bZ4X will also feature a solar roof.


Hyundai IONIQ 5

Hyundai IONIQ 5


Unfortunately, the Hyundai IONIQ 5 is a very expensive electric car. An electric car similar to the Pininfarina B0 with starting price of 20.000 euros featuring a 300 W solar roof, a 50 kWh LFP (LiFePO4) battery and 100 kW fast charging capability would be perfect for many people. Don’t you agree?


Finally, here is the latest video by Sono Motors demonstrating the solar integration in the Sion.



What do you think? Should electric cars get solar panel roofs? If optional, how much would you be willing to pay for a 300 W solar panel roof in an electric car?



More info:

Pedro Lima

My interest in electric transportation is mostly political. Iโ€™m tired of coups and wars for oil. My expectation is that the adoption of electric transportation will be a factor for peace and democracy all over the world.

21 Responses

  1. NickM says:

    I originally saw this on on the Aptera prototype and thought “Another stupid PR stunt”, since the same solar array on the roof of your house will be cheaper and generate more energy. I’ve since decide that it’s perhaps not a bad idea, because the solar is right there on your car — no need to add storage as your car already has a battery, no infrastructure needed to transmit this energy from where it is generated to your car. Of course, cost will be the big sticking point — it needs to be relatively inexpensive to add.

  2. Jonas says:

    Sono Motors has talked about up to 35 km from solar/day for years, now they have to prove it. 400W at noon makes that unrealistic.
    Better to build a car with better cW and lower consumption, that will be more efficient.
    I doubt they will make it into production.

    • Pedro Lima says:

      Unfortunately I also doubt it’ll make it into production, that’s why I didn’t cover it as much as others electric cars. Nonetheless, electric concept cars can be useful to test new ideas to implement.

      Sometimes startups don’t really want to start mass production, they just want to sell an idea to a company already in the market. Maybe that’s the goal of Sono Motors.

  3. liion says:

    Who would be silly enough to park its car in bright sunlight when the solar panels would be useful?
    Especially with a black paint model as advertised?

    • Pedro Lima says:

      Maybe it’ll come with an on-board oven ๐Ÿ™‚

      That is one of the reasons why I also prefer white cars, one more advantage of the Pininfarina B0.

      Hopefully Sono Motors rethinks the Sion before it enters into production and makes it more similar to the Pininfarina B0.

      • Mike/Liverpool says:

        Hi Pedro
        What do you think about Hydrogen?
        Either Fuel cell or even burning it?
        Am told F1 will be going two stroke in 2025, might be burning H2…………….

        • Pedro Lima says:

          Hydrogen is great for large corporations since we can’t produce and compress hydrogen at home. BEVs are not only safer, but also way more efficient and democratic.

          That’s the reason why the former U.S. president George W. Bush pushed for the hydrogen fuel initiative. Keep large corporations and their monopolies happy.

        • Leo B says:

          About racing on hydrogen:

          So far Toyota has been very secretive about its hydrogen combustion engine, but taking part in a race (Fuji 24h endurance race) means some information has come out. The engine is a modified version of the 1.6 liter turbo Yaris GR rally engine, but Toyota hasn’t disclosed horsepower. In the Fuji race the Corolla HCE only outpaced the slowest ST-5 class cars (Honda Fit/Toyota Yaris cup racers), so I don’t think it has more than 200 horses. The petrol version in the Yaris has 265 hp.

          Toyota has said the H2 tanks in the Corolla HCE are enlarged from the Mirai, 180 liters instead of 140 liters. Now why would you say liters if you don’t give us the storage pressure, mr Toyoda? You want to hide the energy storage capacity? Fortunately we know the Mirai stores about 5,6 kg H2, so the Corolla racer should take a little over 7 kg. 7 kg H2 equals 230 kWh.
          Toyota said the Corolla could do 10 laps of the 4,5 km Fuji circuit on a full tank. Average consumption on race speed: 5130 Wh/km.
          The Corolla’s fastest lap was just over 2m 4s, or roughly 130 kph.

          In April Formula E visited the Valencia racing circuit for two races. The first one was in the wet, but the second race was dry. Fastest race lap was 1m 30s over 3,38 km, or roughly 135 kph. Slightly faster race speed than the Corolla, but close enough to compare.
          The Formula E cars have a 54 kWh battery and do the entire race on a single charge. The winner covered 30 laps, or just over 100 km distance at an average speed of 130 kph. Average consumption for the FE car: 540 Wh/km.

          So we know fuel cell cars are 3x as inefficient as BEVs. Now we know HCE cars are 10x as inefficient as BEVs. Horrible.

          Bonus observation:
          -Toyota had to refuel the Corolla in a secluded section of the paddock because the hydrogen storage didn’t comply with the safety rules. The Corolla was refuelled from pressure cilinders. During refueling the pressure drops in the cilinder and rises in the car’s tank, so they actually needed to switch cilinders halfway through the proces to get the job done in 5 minutes.
          -The Corolla did finish the race but needed lengthy repairs (apparently not related to the hydrogen system) somewhere in the race. So it was dead last, 150 laps behind the one but last car, that was already 200 laps down on the winner (who did about 700 laps).

    • antrik says:

      There isn’t much paint, with most of the surfaces covered in solar cells…

  4. antrik says:

    A 62.5% extra power from the non-roof panels is very significant.

    And why would it affect crashworthiness?…

  5. Leo B says:

    Repeat winners of the Australian Solar Challenge race have used their knowledge to come up with what might be a workable solution (if you have the money):
    Homepage | Lightyear
    From the Netherlands, yeah!

    • Pedro Lima says:

      Unfortunately the Lightyear One has a price tag of 150.000 euros.

      But yeah, they shows us whats makes sense, solar panels on the top and good aerodynamics.

      • Frederico Matias says:

        Yeah, Aero should be a major concern for manufacturers….

        The other day when I was cleaning the 40kwh Leaf I noticed that the front is so full with “stuff” that it is impossible to have good aero…. all too many different parts and not so slick design…I wish there were some specialized aeromod companies to help our normal cars being more efficient (without charging us tons of money please).

  6. ealib says:

    Pedro, I think we should not underestimate the contribution of PV panels, even if small or marginal, in the total energy budget of a car.

    The main goal being reducing to the minimum possible what we burn. Burning (or “reducing” in case of FC devices) is our common enemy.

    Underestimating minor energy contributions may be a silly mistake we tend to make similar to not paying attention to TCO in case of EVs vs ICE.

    • Pedro Lima says:

      The ROI (Return of Investment) of solar panels on the sides of a vehicle is extremely low. As for solar panels on the roof and hood I’m totally on board. The Pininfarina B0 is my ideal electric car.

      • Ulrich says:

        The beauty of having PV on the sides, especially for the Sono Sion, is that installation is already part of the moulding process of the side panels – also the infra-structure/control unit is already developed and in place.

        I also expect the solar earnings to still improve by some margin (it already can go up to 545W at this time, rather than the 442W shown above) – which then would make the side panels in sum contribute more to the total earnings than an extra-fitted solar panel for extra money, e.g. of an Hyundai Ioniq 5 with 205W. With the Sono its already part of the package.

        And please don’t compare a โ‚ฌ 25.500 Sono Sion to a โ‚ฌ150.000 Lightyear One – noone compares a people’s car to a luxury sedan. And irrespective of the amazingly efficient consumption of the LY1, it will probably never be able to match the low TCO of the Sion or match it in terms of sustainability … – it’s always question of what you want of a car …

  7. Rok says:

    Ioniq 5 seems to be very unefficient in cold and highway speeds which is quite uncommon for Hyunda              Ioniq 5 – Full range test at 130 km/h in the worst conditions 98-6%      

  8. Famlin says:

    Only solar panels on roof makes sense, not on sides. However placing battery on side will add to strength.
    How about iron in LFP added for strength. Just kidding.

  9. Very well presented. Every quote was awesome and thanks for sharing the content. Keep sharing and keep motivating others.

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