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This idea will never be practical but it also seems it won't die. 69 miles per week of charging. Assuming the car is sitting outdoors all week and the weather i

• onethought 6y ago
  A Tesla has solar panels? I’m pretty sure this car can be plugged in too. In fact it has bidirectional charging, so a parking lot of these things could (theoretically) be connected into a huge solar system charging all the cars
  • liamkinne 6y ago
    On their Twitter there’s video showing it getting 100W in full sunlight. That’s the equivalent to 0.5m^2 of rooftop solar. It’s just not worth the effort of putting the cells on the car.
    • onethought 6y ago
      So a car park of them would generate many kWs. Why isn’t it “worth” it... turning car parks into solar farms sounds pretty cool to me.
      • bobthepanda 6y ago
        Because they'd barely charge themselves, let alone feed anything back into the grid?
        • onethought 6y ago
          True. Much better to just not generate any power so that they don’t charge themselves at all and don’t feed anything to the grid.
          • GauntletWizard 6y ago
            Much more effective than putting solar panels into the roofs of cars would be putting those same solar panels into solar roofs above parking lots. Much lower installation and maintenance costs.
            • thombat 6y ago
              And now the parking lot has a roof, giving a nicer environment for the drivers and cars.
          • onion2k 6y ago
            It'd be a more efficient use of money and resources to put the solar panels on a roof to generate more electricity than they'd generate on a car, and make a car with a bigger battery rather than solar panels. So yes, your sarcastic remark is actually 100% correct.
            • labcomputer 6y ago
              > It'd be a more efficient use of money and resources to put the solar panels on a roof to generate more electricity than they'd generate on a car This is an under-appreciated point by the solar car advocates. In order to get anywhere close to a practical self-charging car, you have to put panels on an area equivalent to covering the entire surface of the car (including the windows!). For a conventionally-shaped car, approximately 1/3rd to 2/3rds of those panels (depending on the orientation of the car w.r.t. the sun) are producing essentially zero electricity. Either because they are actually facing away from the sun, or just at such an extreme angle to the sun. In other words, you get between 50% to 200% more power by taking those panels off the car and slapping them on a roof. The difference in practice will be much greater in urban environments because buildings tend to shade the street (where cars park).
              • onethought 6y ago
                But doing it is what drives innovation... Battery tech is improving at crazy pace because everyone is using batteries for everything now. You don't think the same would happen if wide spread adoption of solar started happening? Arguing: "Technology isn't good enough yet, so we shouldn't try"... how do you expect to make it good enough?
      • mike_d 6y ago
        Around here many parking lots have covered roofs made of solar panels and electric charging stations. Much more efficient than trying to put panels at sub-optimal angles all over a car.
      • Robotbeat 6y ago
        Because bidirectional car chargers cost thousands more than regular L2 chargers.
        • onethought 6y ago
          I'm confused by this... they are built into the car already. You just plug one car into another the cost of the charger is already realised.
      • unionpivo 6y ago
        because neither solar panels, cables or charging network (to connect the cars) is free (money and emissions).
        • onethought 6y ago
          But the alternative (a normal EV) still requires all the same cables and charging network. Or the other alternative, the shipping of petroleum on huge trucks to millions of locations. But yeah, I'd draw the line at solar panels on car roof tops too... the excess is too much.
      • JoeAltmaier 6y ago
        Naïvely, "more panels == more electricity". But since we haven't run out of efficient places to put panels, that means any put in ridiculous places (on top of cars; under sidewalks etc) are not a good use of panels. Panels must be positioned to face the sun, must be unobscured, must be in daylight during prime hours to make it worthwhile. Car roofs are often none of those things. You want car parks turned into solar stations? Then mount them in the car park over the cars, angled at the sun permanently. Its a simple change, cheaper, and works many many times better. And gets crap off your car making it lighter and reducing drag.
• Hypocritelefty 6y ago
  Why do you have to bring fraud Karen in to everything?
• fulafel 6y ago
  That's enough for a lot of car use cases. And more cases if you do this in combination of a top up charge every once in a while.
• throwawayzRUU6f 6y ago
  + for the cost of these panels and assembly/maintenance complexity, you could simply get a few extra kWh of battery, helping with range, charging speed, acceleration or regeneration
• koksik202 6y ago
  For people using their cars once or twice a week to drive 10km to do groceries this will suit them and with having more housing estate with no basic amenities within walking distance this will defiantly fit families with a main car for work commute and second car for small trips like this while one parent is at work with fossil fueled car
  • SideburnsOfDoom 6y ago
    > For people using their cars once or twice a week to drive 10km to do groceries this will suit them Wouldn't they be even better suited to a regular electric car, parked under a roof of solar panels? The simple flat solar roof will be cheaper to make, and be a larger useful surface. And easier to replace, will keep the weather off the car, reduces car weight, etc.
    • rini17 6y ago
      That requires ownership of property. There are plenty of people that, say, rent a basement of a suburban home, park on the street and the owner is not inclined to install solar or provide convenient access to charging. Of course it won't help much but it does.
      • SideburnsOfDoom 6y ago
        High-density living requires high-density solutions, e.g. solar on the building roofs.
        • scbrg 6y ago
          And magic wireless transmission of electricity from said roofs to cars parked in the street.
          • SideburnsOfDoom 6y ago
            Why? Wires up and down building are nothing new. Your objection does not seem reasonable.
• jillesvangurp 6y ago
  Lots of cars don't drive much more than this per week and just sit outside on the drive way or parking lot. They are only used for short trips to work or shops. Solar charging ensures you only rarely have to plug it in to top it up, which is convenient. It also means that if you leave it sitting outside for long periods of time, it will be topped up rather than slightly drained when you get back to it. That convenience is not worth a lot of course but solar panels are cheap. And also, not having to pay for the electricity is nice. E.g. my mother has a car that averages less than 3000 km/year (seriously). With this, she'd never have to plug it in (or rather visit a petrol station). My parents live in a small village and most of the trips are basically 15km round trips to a near by city. Something like this but a bit cheaper would be perfect for them and decimate their fuel expenses. Will this cover all your needs? No of course not. But solar panels are cheap so the added cost of this convenience might be worth it.
  • mavhc 6y ago
    Those cars shouldn't exist at all though, massive waste of resources, renting cars should be much much simpler and cheaper
    • darawk 6y ago
      Lots of people have a 10 mile or less round trip commute. At that distance, you can drive to and from work every day using this car. I don't think most people would want to rent a vehicle for this.
      • bayindirh 6y ago
        ... and if I'm going to rent it for 24 hours, why not buy it in the first place?
        • lpcam33 6y ago
          The environmental cost of making the car takes a reasonable amount of the resources used in is lifecycle. So in the case you only need the car for a few miles a week you should consider alternatives. Maybe village councils should have a car to be shared by all.
• marco_craveiro 6y ago
  I think in Europe many people (including myself) do less than 69 miles per week. We rely a lot on public transport for commuting and use cars only for a few things during the week. I suspect the target market will be very large here.
  • IkmoIkmo 6y ago
    Not sure where the 69 figure comes from. Top post has more info: > As a back of the envelope calculation, if you covered the ~2.44 m2 roof of a VW ID3 with solar panels you'd probably see somewhere in the region of 244 kWh / year (based on typical UK solar panel generation per year - this would be more in a sunny place). At 4.3 miles/kWh that gives you just over 1000 miles / year of self charged driving. The 4.3 is pretty optimistic, most cars are rated around 3 miles per kwh, but I digress. Optimistically it'd mean 1000 miles per year or 19 miles per week, or 2.7 miles per day. I'd say firstly, this is already a niche category. The average car drives 30 miles a day, or more than 10x what this would charge under optimistic mileage. Second, the extra weight would likely make this comparison even worse. Third, not really cost-efficient, either, to install a complete solar system for every 2.5 metres. Much of the cost isn't in the panels but in the system around it. Fourth, I doubt even the 69 mile a week category of people will still mostly have personal cars within 5-10 years. The flexible car rental market is taking off. In Amsterdam for example there's now about 100 thousand users of Sharenow alone, one of the multiple car rental providers, on a population of about 800 thousand people. Anyone who drives 69 miles a week or 10 miles a day, is typically better off renting. At a speed of 20 miles per hour you're looking at 30 minutes or 6 euros per day for your complete car usage costs, i.e. 180 a month. That's less than most cars (300-400 a month) cost in insurance, deprecation, taxes, fuel and parking in Europe. These companies are expanding sufficiently to allow most people in this low-usage group to do away with a personal car within 5 years I think. By the time these solarpanel cars could even start coming online, it's likely that most cars will have increased usage rates and that these solar panels won't even power a few percent of the mileage.
    • silvestrov 6y ago
      The average miles per day does not matter. It does not need to be usefull to everybody before it is useful to anybody. What matters is the lowest 25% percentile. Getting 25% of the market is enough.
• dazc 6y ago
  I drive 4 miles to my office and back, Monday - Friday. *I only drive because, with no footpath most of the way, it's dangerous to walk and I would not feel safe cycling (the road attracts many idiot drivers because there is almost zero chance of encountering police).
• practicalpants 6y ago
  Charging based on regenerative breaking would probably give a far greater amount of energy than this solar panel approach.
  • throwaway81523 6y ago
    All or almost all electric cars already have regenerative braking. The energy recovered from braking has to come from somewhere. I'm surprised someone is doing this with a car but I've thought it somewhat feasible for a van with a large flat roof. I do wonder if the solar cells will be a theft and vandalism target if the car is left parked outside in public all the time.
• iso1631 6y ago
  Would certainly do me - 3 mile trip to school and back eight times a week to drop the kids off, 50 miles a week, parked on the driveway. 3 million cars in the UK do less than 3000 miles a year, 1.8 million do less than 2000.
• Shivetya 6y ago
  Sixty nine miles a day and I would be cheering but per week is a non starter. If it were sufficient if you had such low driving needs why would you even have a car in the first place? What interest me in designs like this is, can it receive sufficient power to overcome battery maintenance in cold weather even while sitting
• jack_riminton 6y ago
  With increasing density of batteries and lightening of cars, there's no reason why it should die
• legacynl 6y ago
  This car can do both? How is that not a clear improvement?
• coldcode 6y ago
  For a site devoted to people who love technology this is short sighted thinking. People thought the iPhone was a gimmick too that would never sell. You are looking at a development model of an idea: what happen 10 years down the road when solar technology improves like everything else and becomes light and more efficient. People thought Tesla would never work as well when it started. People thought Ford would never succeed either. New technology is always a crapshoot, some pay off, some don't; but without a long term view we would still be driving a horse and buggy.
  • rbanffy 6y ago
    > People thought the iPhone was a gimmick too Industry experts thought the iPhone was a gimmick. I still remember "No wireless. Less space than a Nomad. Lame"
  • labcomputer 6y ago
    > For a site devoted to people who love technology this is short sighted thinking It's not short sighted thinking: Most people who use this site can do basic arithmetic. The solar radiance under AM1.5 (which approximates the surface of the earth at the latitude of Europe, the US, or China) is around 1000 kW/m^2. The very best multi-bandgap solar cells in the lab today are about 47% efficient at converting sunlight to electricity. The very best DC-DC converters have about 95% efficiency in practice. That means upper bound on energy production is about 445 W/m^2. On a sunny day. At noon. In June. For a panel directly facing the sun. With no shade. That means you need slightly more than 3 m^2 of sun-facing panels at noon to achieve just the charging rate of a basic 120V North American household plug (1.44 kW from a NEMA 5-15, to be precise). That means you need well over 3 m^2 of body-conforming panel to achieve that rate at noon. And that's the best case given infinite money. And production at other times of the day will be lower (even if you assume the car is parked in the middle of a flat desert). Since the sun moves throughout the day, leaving such a car in the sun all day will only charge it about as much as charging from household plug for about 3-5 hours. Showing that is left as an exercise to the reader.
  • Erlich_Bachman 6y ago
    I was there, and I am still wondering - who thought iPhone was a gimimck? Certainly not people in tech? The tablet phones and phones with keyboards already exist, the palm, the windows phones. iPhone was just a better more slick implementation. Maybe some people had doubts that iPhones would to better than Windows phones, but since those already existed, and there was a market for them, why would anyone consider iPhone a gimmick?