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Solar car just toured the US, and will start production next year
41–50 of 90 posts
Re: Solar car just toured the US, and will start production next year
#42a average fullsize car has approximately a 7 square meter roof. assume we get 100% of that. times solar gets maybe 200 watts per square meter = 1.4kw. times 6 hours of full solar (if you are lucky) = 8.4kwh. divided tesla model 3 gets 2.4 kwh per mile (per below) ~ 4 miles range?
The model 3 is around 2.4 kWh per mile. Plus if you get some fold out panels you could at least double that surface area. Now we’re talking 20 miles.
https://www.fueleconomy.gov/feg/PowerSearch.do?action=noform...
Re: Solar car just toured the US, and will start production next year
#43a average fullsize car has approximately a 7 square meter roof. assume we get 100% of that. times solar gets maybe 200 watts per square meter = 1.4kw. times 6 hours of full solar (if you are lucky) = 8.4kwh. divided tesla model 3 gets 2.4 kwh per mile (per below) ~ 4 miles range?
The model 3 is around 2.4 kWh per mile. Plus if you get some fold out panels you could at least double that surface area. Now we’re talking 20 miles. https://www.fueleconomy.gov/feg/PowerSearch.do?action=noform...
that's still 3 miles range without the foldout. also the hours of light are very optimistic at best. i'm assuming full output for 6 hours in a a row.
i've edited to reflect your numbers. still feels low, but: a model 3 long range has ~ 300 miles of range on an 85kwh battery, so 3.5 miles per kwh?
Re: Solar car just toured the US, and will start production next year
#44Solar cars are scam. They are designed to get funding out of investors with poor understanding of technology. Do some basic math. The electric energy harvested with the solar panels is negligible for transportation. And why should we want to move around solar power plants? It makes much more sense to have them stationary. And to connect them to the power grid to sell the energy to others when the sun shines but the b…
The advantage of a solar car has little to do with saving trivial amounts of electricity. IMO, the best use case is for a hybrid which isn’t generally plugged in as now you’re saving gasoline which could quickly pay for the panels. More widely for EV, there is no need to worry how much charge you lose when parked for long periods. Not needing to worry about running the heater or AC during a traffic jam. Being less de…
Why would the panels improve? Monocrystalline silicon cell efficiency has been about the same since the 90s: 15-20% for commercial cells, up to 26% in the lab.
Re: Solar car just toured the US, and will start production next year
#45It's a nice idea, but the black color is going to be a serious problem for car that you park in the sun. I suppose they could have cooling fans running in it while it's sitting, otherwise the interior and battery are going to bake. Any plastic parts that aren't high-temp will go brittle.
Re: Solar car just toured the US, and will start production next year
#46What a biased article: "that comes out to 10 to 20 miles per day, which is near negligible if you’re trying to use the car for anything other than city errands." 10-20 miles per day is a big chunk of a commute for a lot of people. This is hardly negligible.
How many of those people leave their car parked in direct sunlight the entire day? I use my car for city errands but it spends 99% of the time in a parking garage. The few minutes a day my car is outside in use could provide what, a hundred meters worth of juice? Useless. Even if I wanted to store my car parked on the street, I don't even know where in my neighborhood I could do that. There are trees and tall buildin…
My car has spent basically 100% of the last 5 years exposed to open sky, ever since moving away from a place with trees. Both my home and workplace parking situations have good sun exposure. Most of the spaces at my apartment complex have good sun exposure as a lot of the spots are set back from buildings.
Re: Solar car just toured the US, and will start production next year
#47Solar cars are scam. They are designed to get funding out of investors with poor understanding of technology. Do some basic math. The electric energy harvested with the solar panels is negligible for transportation. And why should we want to move around solar power plants? It makes much more sense to have them stationary. And to connect them to the power grid to sell the energy to others when the sun shines but the b…
Its a $30K car with a range of 190 miles and can charge itself 40 miles a day in optimal conditions. I live in southern california and I drive about 20 miles a day under normal conditions. Today I have solar panels on my house and a plug-in electric car, but I think the value proposition of a $30K car that I never need to plug in or refuel (during normal conditions) is pretty compelling. The solar panels on my home c…
"can charge itself 40 miles a day in optimal conditions." Using random numbers from Google for a Tesla 3 for an example, it has a 50kWh battery and 305 miles of range. That's 164Wh per mile. 40 miles would require 6,560Wh.
Assuming you leave the car in perfect sunlight for a full 8 hours every day, and there's no cloud, and you get 100% sunlight for the entire 8 hours, then you'd need enough panels to produce 6560Wh / 8hr or 820W.
I could probably barely fit 300W-400W worth of panels on top of my vehicle, and that's with covering the hood, trunk, roof, everything.
So even in the MOST IDEAL possible scenario, where you have your car in perfect sunlight for 8 hours a day, you're not even half way to producing 40 miles per day.
Re: Solar car just toured the US, and will start production next year
#48Solar cars are scam. They are designed to get funding out of investors with poor understanding of technology. Do some basic math. The electric energy harvested with the solar panels is negligible for transportation. And why should we want to move around solar power plants? It makes much more sense to have them stationary. And to connect them to the power grid to sell the energy to others when the sun shines but the b…
>Solar cars are scam. They are designed to get funding out of investors with poor understanding of technology. They certainly exist, it's just not the performance numbers people want from their vehicle. >Do some basic math. The electric energy harvested with the solar panels is negligible for transportation. Thats not true; and also depends on your usecase. Aptera is certainly going to come to market with a product f…
What makes you think the Aptera is a death trap? It's made out of carbon fibre.
Re: Solar car just toured the US, and will start production next year
#49Earlier quoted context omitted.
The advantage of a solar car has little to do with saving trivial amounts of electricity. IMO, the best use case is for a hybrid which isn’t generally plugged in as now you’re saving gasoline which could quickly pay for the panels. More widely for EV, there is no need to worry how much charge you lose when parked for long periods. Not needing to worry about running the heater or AC during a traffic jam. Being less de…
Why would the panels improve? Monocrystalline silicon cell efficiency has been about the same since the 90s: 15-20% for commercial cells, up to 26% in the lab.
The article mentions the Sion is using lower efficiency polymer-based cells integrated into its body panels. But also the curved panels ideal for aerodynamics means a real tradeoff, as current curved panels have poor efficiency.
Right now nobody is going to heavily invest in solar car R&D, but if this becomes a common feature the simple desire for longer solar ranges is going to push efficiency.
Re: Solar car just toured the US, and will start production next year
#50Earlier quoted context omitted.
Outside of the geeky cool factor, what precisely is the value proposition? You say you have solar on your house. So is it that you don't have to remember to plug in? Is that a big deal for most people? What if there was some kind of auto-connect when you pulled into your parking spot? Would that be better than carrying around solar panels that don't point at the sun? I read through the absolute technical limits of so…
Well electricity in the Bay Area costs about $0.50 per kWh (or $0.25 per kWh at night using the ev2-a plan, though it makes everything else more expensive). Having a car that can gradually recharge itself over the day can actually save hundreds of dollars per month (my last bill was like $600), without having to deal with the hassle of installing rooftop solar and having to pay extra money just for having solar insta…
Right but what's the problem with plugging into the solar panels that stay in place?