4 ms·

8 hours in the Sun is good enough for 2 hours of driving, according to that blurb. That’s like 100 miles of range added per day, and the battery can buffer mult

8 hours in the Sun is good enough for 2 hours of driving, according to that blurb. That’s like 100 miles of range added per day, and the battery can buffer multiple days. Who drives 700 miles per week? Maybe 10%? Aptera’s car charges 40 miles per day, which is the same as the average American’s round trip commute (and can buffer during the weekend as well). The overall end point for solar charging is you’re charging enough that you don’t have to plug in unless you’re going on a road trip. I don’t know why it is hard to understand the basic idea or value of this. Most working people commute by car, and this concept would potentially allow all of the commuting miles by most people to be handled by the Sun. Home charging just no longer required. For sunny parts of the world (where people don’t park in garages, where they could plug in), that’s pretty awesome.

coryrc 4y ago
> 8 hours in the Sun is good enough for 2 hours of driving, according to that blurb. That’s like 100 miles of range... Nope! They might want you to think that with misleading wording, but you'd be lucky for 2 hours of driving at 12 mph. And, again, that's only if the car gets full sun the entire day. At those distances, just get an electric bicycle. EDIT: I don't know what blurb you refer to, but my search engine says https://sonomotors.com/en/sion/ https://sonomotors.com/en/sion/ used to say "on average 112km/week".
- Robotbeat 4y ago
  It was jvanderbot’s quip: “Yeah, if the panels are so efficient that 8 hrs of sitting can charge 2 hrs of driving, then just put those panels on your roof and wire them into a garage charger.” Generally, it helps to take comments in context… In his hypothetical, that’s clearly more than enough for the average person’s commute. And even if it isn’t quite enough, it could reduce the frequency you need to make trips to a fast charging station (effectively like having a twice as large of a battery), if you cannot charge at home. Charging stations usually are substantially more expensive than residential, maybe 3-4 times the price, and residential is 4 times the price of utility scale solar power (due to buffering and distribution, etc). So there’s a good financial case for it if you can get the cost low, plus you have the added convenience. Sono’s solar wasn’t very good. Lightyear and Aptera’s ability to add up to 40 miles per day is pretty useful… if they can get the cost down.
  - sokoloff 4y ago
    > Generally, it helps to take comments in context… That’s true, but when the projection is off by roughly a factor of 10, it’s helpful to bring in the actual data.
nradov 4y ago
Aptera is lying. There is no way that a typical driver will get 40 miles per day of solar charging with the panels that they're using.
- Robotbeat 4y ago
  Typical driver? Typical Aptera driver? Possibly… Keep in mind an Aptera has the volume and weight and frontal area more comparable to a covered bicycle or golf cart while its top surface is mostly the same as a normal car. So even if regular cars can’t do it, an Aptera maybe can. If a Model 3 can get 4 miles per kWh, I can believe an Aptera can get 10miles per kWh, as it has only 2 seats (not 5), and is extremely streamlined. Top surface of an Aptera is about the same as a Model 3 (8m^2 if you treat it as a rectangle), and all of the top part would basically be covered with solar cells. (Even the front window would have cells on the dash to collect the sunlight going through it.) if the total full factor of that rectangle is 45% cells, with 20% efficient cells… that’s 800 Watts. With 5 hours effective sunlight per day, 4kWh per day is doable in sunny locations. 40 miles per day. With just 800W, it’s okay if you’re using $2/Watt high efficiency conformal cells (as opposed to 10¢/Watt dirt cheap cells) as the cost is just $1600. That will pay back your Electrify America bill in just 2.5 years… or Supercharger (comparable to gas prices) in 3 years. Additionally, if you live in a place with crushingly high electricity prices but still has sun, you can pay back as well. And is more convenient than charging. I hope Aptera’s business works, as the idea has merit.
jvanderbot 4y ago
Viability of 1hr per 4hrs charging aside... I think I had implicitly assumed that most people with commutes do not park outside (and thus would miss the valuable daylight charging hours, and would thus be better off charging a wallpack at home). But in hindsight, I think that's incorrect. _most_ people probably park outside at work, wouldn't they? those statistics would make or break a solar car.
- Robotbeat 4y ago
  By far most, I’d say. And actually I’d say that parking garages and residential garages are both natural places for plug in charging. It’s street parking or vast (unlit) outdoor parking lots that would be a challenge for plug in charging, exactly the places that would work fairly well for solar car charging. So I think it’s a valid niche. The issue is it’s still annoyingly expensive to place solar cells on car surfaces, and really we should use those high efficiency multijunction cells. Tandem perovskite cells are very promising there, getting both high efficiency (over 30% and rising) and low cost. But conforming shapes to car bodies is also a challenge. However if those can be solved, it’d be great to have this option.

coryrc 4y ago

> 8 hours in the Sun is good enough for 2 hours of driving, according to that blurb. That’s like 100 miles of range... Nope! They might want you to think that with misleading wording, but you'd be lucky for 2 hours of driving at 12 mph. And, again, that's only if the car gets full sun the entire day. At those distances, just get an electric bicycle. EDIT: I don't know what blurb you refer to, but my search engine says https://sonomotors.com/en/sion/ https://sonomotors.com/en/sion/ used to say "on average 112km/week".

Robotbeat 4y ago
It was jvanderbot’s quip: “Yeah, if the panels are so efficient that 8 hrs of sitting can charge 2 hrs of driving, then just put those panels on your roof and wire them into a garage charger.” Generally, it helps to take comments in context… In his hypothetical, that’s clearly more than enough for the average person’s commute. And even if it isn’t quite enough, it could reduce the frequency you need to make trips to a fast charging station (effectively like having a twice as large of a battery), if you cannot charge at home. Charging stations usually are substantially more expensive than residential, maybe 3-4 times the price, and residential is 4 times the price of utility scale solar power (due to buffering and distribution, etc). So there’s a good financial case for it if you can get the cost low, plus you have the added convenience. Sono’s solar wasn’t very good. Lightyear and Aptera’s ability to add up to 40 miles per day is pretty useful… if they can get the cost down.
- sokoloff 4y ago
  > Generally, it helps to take comments in context… That’s true, but when the projection is off by roughly a factor of 10, it’s helpful to bring in the actual data.

nradov 4y ago

Aptera is lying. There is no way that a typical driver will get 40 miles per day of solar charging with the panels that they're using.

Robotbeat 4y ago
Typical driver? Typical Aptera driver? Possibly… Keep in mind an Aptera has the volume and weight and frontal area more comparable to a covered bicycle or golf cart while its top surface is mostly the same as a normal car. So even if regular cars can’t do it, an Aptera maybe can. If a Model 3 can get 4 miles per kWh, I can believe an Aptera can get 10miles per kWh, as it has only 2 seats (not 5), and is extremely streamlined. Top surface of an Aptera is about the same as a Model 3 (8m^2 if you treat it as a rectangle), and all of the top part would basically be covered with solar cells. (Even the front window would have cells on the dash to collect the sunlight going through it.) if the total full factor of that rectangle is 45% cells, with 20% efficient cells… that’s 800 Watts. With 5 hours effective sunlight per day, 4kWh per day is doable in sunny locations. 40 miles per day. With just 800W, it’s okay if you’re using $2/Watt high efficiency conformal cells (as opposed to 10¢/Watt dirt cheap cells) as the cost is just $1600. That will pay back your Electrify America bill in just 2.5 years… or Supercharger (comparable to gas prices) in 3 years. Additionally, if you live in a place with crushingly high electricity prices but still has sun, you can pay back as well. And is more convenient than charging. I hope Aptera’s business works, as the idea has merit.

jvanderbot 4y ago

Viability of 1hr per 4hrs charging aside... I think I had implicitly assumed that most people with commutes do not park outside (and thus would miss the valuable daylight charging hours, and would thus be better off charging a wallpack at home). But in hindsight, I think that's incorrect. _most_ people probably park outside at work, wouldn't they? those statistics would make or break a solar car.

Robotbeat 4y ago
By far most, I’d say. And actually I’d say that parking garages and residential garages are both natural places for plug in charging. It’s street parking or vast (unlit) outdoor parking lots that would be a challenge for plug in charging, exactly the places that would work fairly well for solar car charging. So I think it’s a valid niche. The issue is it’s still annoyingly expensive to place solar cells on car surfaces, and really we should use those high efficiency multijunction cells. Tandem perovskite cells are very promising there, getting both high efficiency (over 30% and rising) and low cost. But conforming shapes to car bodies is also a challenge. However if those can be solved, it’d be great to have this option.