658
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 16 Oct 2023
658 points (95.8% liked)
Technology
59081 readers
3484 users here now
This is a most excellent place for technology news and articles.
Our Rules
- Follow the lemmy.world rules.
- Only tech related content.
- Be excellent to each another!
- Mod approved content bots can post up to 10 articles per day.
- Threads asking for personal tech support may be deleted.
- Politics threads may be removed.
- No memes allowed as posts, OK to post as comments.
- Only approved bots from the list below, to ask if your bot can be added please contact us.
- Check for duplicates before posting, duplicates may be removed
Approved Bots
founded 1 year ago
MODERATORS
There is no actual information on how self sufficient the car actually is. There is only 1 number which states how long the car drives on a sunny day with solar+battery combined.
The car probably needs to charge for days via the solar panels in order to fill up the battery.
In other words, the solar only adds about 50-60km/day to the battery.
Another case of putting solar panels on specific things not being a great idea. Chuck the panels on a convenient surface pointing at the sun and connect them to the grid. Connect your load to the grid. Job done.
We can talk about solar windows/roads/cars/rivers/canopies when we've run out of space on houses and commercial roofs. They already have grid connections, structure, and are protected from damage.
How do you say that so nonchalantly
Compared to the 700km claimed range (which seems very optimistic), that implies you would need to let the car sit for two weeks to charge on solar alone - more if the weather is not totally perfect or there is any shade.
So if you're wanting to do a multi-day road trip, it's of stuff all use. You're going to be relying on the big battery and the grid; the solar is a rounding error.
If you're planning to do <50km/day commuting/shopping etc... please don't get an off-road SUV tank, and probably not anything with 700km of range. Get something that weighs half as much and put 5x as much solar on your roof. It'll still be cheaper overall and the panels will last longer.
If you're actually in the small segment that needs off-road capability and an SUV (say, a farm run-around), congratulations. Definitely don't get a car with solar on the roof because it will immediately be covered in dust, and the minor dents and whoops-a-small-tree-fell-on-it will break the panels in the first year. You also probably want to park it in the shade wherever possible.
Again, stick 5x the panels on the garage roof and get something cheaper.
It can be useful if you live out of the grid, like in the middle of Morocco dessert.
Even if you're off grid, it's still better to put the panels and most of the battery on a house.
You'll get much better yield because the panels can be pointed in exactly the right direction and won't be covered in road dust, plus there's far more space available.
Putting a smaller, lighter battery in the vehicle is going to reduce its energy consumption, as is using a shape designed for low drag rather than a shape set up for optimal solar.
Yeah, nothing on how much is pre-loaded battery and how much is solar charging, or how long the trip was.
None. It was entirely solar based. This is their 2nd vehicle smaller and lighter than the camper they made. So 440 ranged is fully charged, otherwise 620 miles in a week and a half off of just solar.
there doesn't need to be. It's not. plain and simple. There just isn't enough area on a car's body (remember, most of them won't even be oriented properly most of the time) for panels to generate enough power for self sufficiency. Even if the panels were 100% efficient. This will always be the case for any solar car.
assuming average conditions, somewhere on the order of 20 kw at cruising speed. More is needed to accelerate.
On the earth's surface, we get about 1kw per meter squared of energy from the sun. That's before factoring in inefficiencies in the panels, inefficiencies due to panels not oriented correctly, the battery charging system etc. Actual usable energy generated is significantly less than that.
So, with 100% efficient panels, you would still need, in theory, at minimum around 20 meters squared of perfectly efficient, perfectly oriented panels. Probably about 3 to 4 times more, in practice. There just is not enough surface area on a car.
I mean that's just not true unless you're referring to the very narrow scope of powering itself while driving down the highway at 70MPH.
With a sufficiently efficient design and enough solar panels and sun exposure, like can be seen on the Aptera, you can get 30-40 miles of range/day, which is more than sufficient for a daily commute.