Well, “they did the math”. If you read the article, they’re saying 32km/day in Stuttgart and 47/day in LA, and then extrapolating to 55/day in Australia. This is from their practical trials.
The kicker to the kicker is that they are claiming >20% efficiency here. It’s apparently a very revolutionary new paint. The main thing they didn’t cover is how fast it degrades, which has been a huge problem with perovskite-based systems like I bet this is.
Yeah I don’t really see how that’s possible. Even if you get a material that’s able to harvest at 20% efficiency, getting the energy out is a big issue. It’s a lot of power and transporting it through a layer a few micron thick is very rough and leads to huge losses.
I also don’t know what “math” they actually did. I think it was some back of the napkin extrapolations and not actual data. For example they state: “one scientist suggested covering an entire car with the new solar paint, ramping up the surface area to more than 11m2” That leads me to believe they didn’t actually do anything but were just extrapolating and speculating for the press.
They also state: “scientists hardwired the body panels to the Benz’s high-voltage battery”. This makes zero sense. In order for energy to flow from a solar panel into for example a battery, the voltage of the panel needs to be higher than the voltage of the battery. Otherwise the current will flow in the wrong direction. But Mercedes EQS batteries run at 400 volt, you can’t connect “directly” to the battery unless you want the panel to explode and the car to catch fire. And even if you connect it directly into some charger system that can convert the voltage from the panel into something the battery can use to charge, you wouldn’t want to do it like that. Including a voltage optimizer in the system is key for getting efficiency out of a solar panel.
I think some journalist misunderstood some Merc tech demo and made up this BS story.
“They” here was you. You did the math. That was a bit ambiguous, sorry.
Journalistic misunderstanding is possible, I guess. There’s no way it’s just a wire to the high-voltage motor output - it doesn’t trickle charge off the grid directly either - although omitting the charging system is arguably more of a wording choice.
Well, “they did the math”. If you read the article, they’re saying 32km/day in Stuttgart and 47/day in LA, and then extrapolating to 55/day in Australia. This is from their practical trials.
The kicker to the kicker is that they are claiming >20% efficiency here. It’s apparently a very revolutionary new paint. The main thing they didn’t cover is how fast it degrades, which has been a huge problem with perovskite-based systems like I bet this is.
Yeah I don’t really see how that’s possible. Even if you get a material that’s able to harvest at 20% efficiency, getting the energy out is a big issue. It’s a lot of power and transporting it through a layer a few micron thick is very rough and leads to huge losses.
I also don’t know what “math” they actually did. I think it was some back of the napkin extrapolations and not actual data. For example they state: “one scientist suggested covering an entire car with the new solar paint, ramping up the surface area to more than 11m2” That leads me to believe they didn’t actually do anything but were just extrapolating and speculating for the press.
They also state: “scientists hardwired the body panels to the Benz’s high-voltage battery”. This makes zero sense. In order for energy to flow from a solar panel into for example a battery, the voltage of the panel needs to be higher than the voltage of the battery. Otherwise the current will flow in the wrong direction. But Mercedes EQS batteries run at 400 volt, you can’t connect “directly” to the battery unless you want the panel to explode and the car to catch fire. And even if you connect it directly into some charger system that can convert the voltage from the panel into something the battery can use to charge, you wouldn’t want to do it like that. Including a voltage optimizer in the system is key for getting efficiency out of a solar panel.
I think some journalist misunderstood some Merc tech demo and made up this BS story.
“They” here was you. You did the math. That was a bit ambiguous, sorry.
Journalistic misunderstanding is possible, I guess. There’s no way it’s just a wire to the high-voltage motor output - it doesn’t trickle charge off the grid directly either - although omitting the charging system is arguably more of a wording choice.
Here’s another one where they go into more detail, and even mention the possibility of perovskites independently: https://newatlas.com/automotive/mercedes-benz-solar-paint/
Unfortunately the press release itself doesn’t seem to be accessible, after a quick search.