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Almost all of that is the battery. Even though batteries are coming down in price, they are still very expensive. For example GM’s list price for the Bolt batt

Almost all of that is the battery. Even though batteries are coming down in price, they are still very expensive. For example GM’s list price for the Bolt battery is $15,734. Now this is the replacement cost Bolt owners pay for a new battery not the actual cost, but it gives an indication of their cost. https://electrek.co/2017/06/12/gm-bolt-ev-battery-pack-price-cost/ https://electrek.co/2017/06/12/gm-bolt-ev-battery-pack-price...

ianai 9y ago
How much power does the electric motor need? -edit- found it https://www.quora.com/How-much-power-is-required-by-the-motor-to-run-the-car-electric-car-in-watts https://www.quora.com/How-much-power-is-required-by-the-moto... 80kw to accelerate and 1 kw to maintain. -edit 2- how come no ones put 3 solar panels on top of an EV? Three of the following could output 1 kw and fit in the space available. http://www.solarwholesale.com/wp-content/uploads/2016/10/Silfab-SLA-M-280-and-300-Spec-Sheet-Solar-Wholesale.pdf http://www.solarwholesale.com/wp-content/uploads/2016/10/Sil... Seems like an obvious for electric semis where there’s often plenty of sun (aka an ever increasing portion of the US)
- pjc50 9y ago
  That has to be a typo and the real number more like 10kw - 1kw is 1.3HP, lawnmower engine territory.
- mtgx 9y ago
  Model S has about 500 kW, Model 3 300 kW, Bolt 150 kW, Renault Zoe like 50 kW. As for the other question, the solar panels provide way too little charge for the given area. When EVs are all about to have 100+ kWh batteries soon, it doesn't make sense to have a solar roof top: https://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/15290/Why-the-Tesla-Model-3-Will-NOT-Have-a-Solar-Roof.aspx https://www.engineering.com/ElectronicsDesign/ElectronicsDes...
  - ianai 9y ago
    The numbers in that article seem chosen as low bars to prove a point. There are panels with much greater efficiency/density and lower cost. If it doesn’t make sense today it will in the future. If a company could move their trucks for “free” for 5 hours/day they would.
    - mtgx 9y ago
      I'm not completely discounting it, but 5h seems like a lot for trucks, even if you have more roof area. Tesla's Semi has a 1 MWh battery, which will be drained within a day by most firms, and I imagine Semi 2.0 will have a 2MWh battery. It's hard to imagine the solar panels would keep up with either of them. Even if the panels can generate 100 kWh a day for the trucks, that's still like 1/10 of the day, so more like an hour. But 100 kWh seems really unlikely, even in the future.
    - Dylan16807 9y ago
      > There are panels with much greater efficiency/density Not by a huge amount. You could get 3x that with just about the best solar panel, but they didn't appear to factor in the losses from having the panels facing up-ish and not toward the sun, so you also lose another big chunk of power. > If it doesn’t make sense today it will in the future. Doubt it. Solar panels can only be so efficient. > If a company could move their trucks for “free” for 5 hours/day they would. Sure, but we're looking at more like fifteen minutes. Put the solar panels on the ground. They'll give you more "free" range, with less effort.
- 2sk21 9y ago
  This would also a good idea for countries like India where the sun mostly shines and the electricity grid is weak.
- tehwalrus 9y ago
  1kW to maintain is nonsense. My 11kW limited motorbike (much lower air resistance) can barely do 65mph, sometimes hits 70 on a downhill. Any wind and you won't break 60.
- kalleboo 9y ago
  Priuses have a solar panel on the roof, but all it has the capacity to power is a fan to keep the cabin cool when you park in the sun on a hot day...
  - icebraining 9y ago
    That's the old version; they're claiming the new can add 3.7 miles of range for each day of charging.
- masklinn 9y ago
  These numbers don't pass the sniff test, the World Solar Challenge wouldn't be a thing if it were that easy.
- ju-st 9y ago
  1kw to maintain 5kmph perhaps. To maintain 100-120kmph a car needs around 20kw. The first gen EVs like Renault Zoe have a ~24kwH battery and a real world range of ~100km.
- rcxdude 9y ago
  On top of cars is probably the second-worst place to put a solar panel, just after on the road itself (I say this after having participated in building a solar car). It's extremely difficult to get solar panels to work efficiently in that environment, they're almost never pointing in the right direction, they are frequently shaded (even partial shade will wreck the efficiency of a panel). You're much better off putting them at the charging points.

ianai 9y ago

How much power does the electric motor need? -edit- found it https://www.quora.com/How-much-power-is-required-by-the-motor-to-run-the-car-electric-car-in-watts https://www.quora.com/How-much-power-is-required-by-the-moto... 80kw to accelerate and 1 kw to maintain. -edit 2- how come no ones put 3 solar panels on top of an EV? Three of the following could output 1 kw and fit in the space available. http://www.solarwholesale.com/wp-content/uploads/2016/10/Silfab-SLA-M-280-and-300-Spec-Sheet-Solar-Wholesale.pdf http://www.solarwholesale.com/wp-content/uploads/2016/10/Sil... Seems like an obvious for electric semis where there’s often plenty of sun (aka an ever increasing portion of the US)

pjc50 9y ago
That has to be a typo and the real number more like 10kw - 1kw is 1.3HP, lawnmower engine territory.
mtgx 9y ago
Model S has about 500 kW, Model 3 300 kW, Bolt 150 kW, Renault Zoe like 50 kW. As for the other question, the solar panels provide way too little charge for the given area. When EVs are all about to have 100+ kWh batteries soon, it doesn't make sense to have a solar roof top: https://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/15290/Why-the-Tesla-Model-3-Will-NOT-Have-a-Solar-Roof.aspx https://www.engineering.com/ElectronicsDesign/ElectronicsDes...
- ianai 9y ago
  The numbers in that article seem chosen as low bars to prove a point. There are panels with much greater efficiency/density and lower cost. If it doesn’t make sense today it will in the future. If a company could move their trucks for “free” for 5 hours/day they would.
  - mtgx 9y ago
    I'm not completely discounting it, but 5h seems like a lot for trucks, even if you have more roof area. Tesla's Semi has a 1 MWh battery, which will be drained within a day by most firms, and I imagine Semi 2.0 will have a 2MWh battery. It's hard to imagine the solar panels would keep up with either of them. Even if the panels can generate 100 kWh a day for the trucks, that's still like 1/10 of the day, so more like an hour. But 100 kWh seems really unlikely, even in the future.
  - Dylan16807 9y ago
    > There are panels with much greater efficiency/density Not by a huge amount. You could get 3x that with just about the best solar panel, but they didn't appear to factor in the losses from having the panels facing up-ish and not toward the sun, so you also lose another big chunk of power. > If it doesn’t make sense today it will in the future. Doubt it. Solar panels can only be so efficient. > If a company could move their trucks for “free” for 5 hours/day they would. Sure, but we're looking at more like fifteen minutes. Put the solar panels on the ground. They'll give you more "free" range, with less effort.
2sk21 9y ago
This would also a good idea for countries like India where the sun mostly shines and the electricity grid is weak.
tehwalrus 9y ago
1kW to maintain is nonsense. My 11kW limited motorbike (much lower air resistance) can barely do 65mph, sometimes hits 70 on a downhill. Any wind and you won't break 60.
kalleboo 9y ago
Priuses have a solar panel on the roof, but all it has the capacity to power is a fan to keep the cabin cool when you park in the sun on a hot day...
- icebraining 9y ago
  That's the old version; they're claiming the new can add 3.7 miles of range for each day of charging.
masklinn 9y ago
These numbers don't pass the sniff test, the World Solar Challenge wouldn't be a thing if it were that easy.
ju-st 9y ago
1kw to maintain 5kmph perhaps. To maintain 100-120kmph a car needs around 20kw. The first gen EVs like Renault Zoe have a ~24kwH battery and a real world range of ~100km.
rcxdude 9y ago
On top of cars is probably the second-worst place to put a solar panel, just after on the road itself (I say this after having participated in building a solar car). It's extremely difficult to get solar panels to work efficiently in that environment, they're almost never pointing in the right direction, they are frequently shaded (even partial shade will wreck the efficiency of a panel). You're much better off putting them at the charging points.