4 ms·

generate as much energy over the course of the year as the vehicles consume Yeah right. At what utilization rate? A single charge is ~90KWh, and takes half

generate as much energy over the course of the year as the vehicles consume Yeah right. At what utilization rate? A single charge is ~90KWh, and takes half an hour. Two charges back to back are 180KWh. jws guesses that each slot generates 28KWh/day. A ten slot charging station would only be able to charge three cars without going into the red. Tesla would have to build a lot of very oversized installations in a lot of sunny, rural locations to hit breakeven.

timdorr 14y ago
They could have solar only at some locations and excess capacity to make up for the locations without solar.
- 001sky 14y ago
  Ok, but prob with solar is it does you no good if its not connected to anything. And if they are just putting it into the grid what is the point other than PR?
  - jlgreco 14y ago
    Well for one, you presumably get paid to put power back into the grid. Secondly, is there not value in putting as much power into the grid as you consume anyway?
    - 001sky 14y ago
      The problem is, in the case you propose, Tesla would be creating installations in urban environments. This type of "development" kills their credibility on "green" or environmentalism, etc. Is this kind of thing better than hydropower?
      - jlgreco 14y ago
        Hydropower is pretty gnarly from an environmental standpoint. And I doubt the land they are using would otherwise remain undeveloped.. it is an urban area after all. Perhaps solar in previously undeveloped areas would be better? I doubt that. Developing solar plants in undeveloped areas only to put the charging stations in urban areas (that is where the market demands them after all) hardly seems better than putting charging stations in urban areas and sticking some solar there too. What is there to be gained from not putting solar wherever you can?
        001sky 14y ago
        Hydropower is clean and renewable. Dams are already built, etc. Everything has its tradeoffs, though. Remote solar and wind take up lost of room and are eyesores. Grid connects require large-scale duplication/new assets. But, I think we need less sprawl generally, so I find it hard to support, in particular, urban development where better use could be made of the land.
        jlgreco 14y ago
        If there is anything this continent (or world, for that matter) is lacking, it is space. That said, I think we should be plastering the land we already use with solar panels. Might as well put all those rooftops to use. I also think there is likely a lot to see in the future of non-panel-type solar. That generally involves a much larger or smaller scope than panels though, "medium" sized doesn't work well.
        001sky 14y ago
        What I would be cool with is solar on top of wall mart and home depot and costco...and the like...those are good size square footages. and the assets are already in place. wonder if the roofs would hold =D !
        jlgreco 14y ago
        Absolutely. For that matter, get some solar-panel covered parking lots at those places too so my car doesn't melt in the summer!
schiffern 14y ago
>jws guesses that each slot generates 28KWh/day Again, this is a guess based on a CG rendering on their website. That drawing doesn't constrain Tesla's engineering talent in any way – even without using extra land they could put up solar shade structures over adjacent parking spaces.
- sbierwagen 14y ago
  Adjacent parking spaces, eh? To go from 3 charges a day to 6, right? Assume you've got a couple dozen slots, charging 100 cars a day. (Far, far fewer than an equivalently-sized gas station. If we're going to transition to an electric-only transportation infrastructure, then car changing stations are going to become a common sight) That's 9 megawatt-hours a day. A random solar panel calculator I found guesses that would need ~2000KW of solar panel capacity. So you'll need 8,000 250 watt panels. That'll cover 9,600 square metres, (2.6 acres-- if you're lying them flat, which you won't. A big dedicated solar generation station will use tilted one-axis tracking, which will use a lot more ground space) and cost you (at $410 a panel) a cool $2.4 million. (Google's big solar installation at Mountain View, the one that got so much press, was only 1700KW. Our tiny electric car charging station has to be 17% bigger than it.) Electric car charging uses a lot of power. Solar is great, I love solar, but it's not space-efficient, or cheap. Either Tesla is going to build a national solar generation network on the scale of Germany's move into solar power, all on their own dime, or they're lying through their teeth about charging draw/solar production breakeven.
  - schiffern 14y ago
    Yes, in a couple years there will be more electric cars, but solar power installations are getting less expensive every year. I don't know how long until there are enough electric cars to need "Germany-sized" solar installations, but when they do they'll pay a lot less than Germany did. I don't think Elon Musk would green-light the "100% solar power" line without doing the math. Again: you can argue about whether he's lying, but I can guarantee you he knew exactly the scale of what he was promising. That makes it all the more impressive, imo. Re:lying, I'm imagining at some point they'll transition over to "we buy 100% solar power for SuperChargers", which is fine by me since it's functionally equivalent to what they're doing now.
eps 14y ago
So you are basically saying that Musk is lying. This doesn't sound too much like him, does it? A simpler explanation would be that he's not telling the whole story, and that perhaps they have dedicated solar farms in development/deployment or something to that effect. Don't afraid to dream a little bigger, darling.
- warfangle 14y ago
  Sure doesn't sound like him. He's headed up the first company to commercially resupply the International Space Station, for pete's sake. You bet your ass he quadruple checked those numbers. I'm guessing that the supply at these stations will be much higher than the demand for charging, so they'll make up the cost of "free" by selling wh's back to the grid.

timdorr 14y ago

They could have solar only at some locations and excess capacity to make up for the locations without solar.

001sky 14y ago
Ok, but prob with solar is it does you no good if its not connected to anything. And if they are just putting it into the grid what is the point other than PR?
- jlgreco 14y ago
  Well for one, you presumably get paid to put power back into the grid. Secondly, is there not value in putting as much power into the grid as you consume anyway?
  - 001sky 14y ago
    The problem is, in the case you propose, Tesla would be creating installations in urban environments. This type of "development" kills their credibility on "green" or environmentalism, etc. Is this kind of thing better than hydropower?
    - jlgreco 14y ago
      Hydropower is pretty gnarly from an environmental standpoint. And I doubt the land they are using would otherwise remain undeveloped.. it is an urban area after all. Perhaps solar in previously undeveloped areas would be better? I doubt that. Developing solar plants in undeveloped areas only to put the charging stations in urban areas (that is where the market demands them after all) hardly seems better than putting charging stations in urban areas and sticking some solar there too. What is there to be gained from not putting solar wherever you can?
      - 001sky 14y ago
        Hydropower is clean and renewable. Dams are already built, etc. Everything has its tradeoffs, though. Remote solar and wind take up lost of room and are eyesores. Grid connects require large-scale duplication/new assets. But, I think we need less sprawl generally, so I find it hard to support, in particular, urban development where better use could be made of the land.
        jlgreco 14y ago
        If there is anything this continent (or world, for that matter) is lacking, it is space. That said, I think we should be plastering the land we already use with solar panels. Might as well put all those rooftops to use. I also think there is likely a lot to see in the future of non-panel-type solar. That generally involves a much larger or smaller scope than panels though, "medium" sized doesn't work well.
        001sky 14y ago
        What I would be cool with is solar on top of wall mart and home depot and costco...and the like...those are good size square footages. and the assets are already in place. wonder if the roofs would hold =D !
        jlgreco 14y ago
        Absolutely. For that matter, get some solar-panel covered parking lots at those places too so my car doesn't melt in the summer!

schiffern 14y ago

>jws guesses that each slot generates 28KWh/day Again, this is a guess based on a CG rendering on their website. That drawing doesn't constrain Tesla's engineering talent in any way – even without using extra land they could put up solar shade structures over adjacent parking spaces.

sbierwagen 14y ago
Adjacent parking spaces, eh? To go from 3 charges a day to 6, right? Assume you've got a couple dozen slots, charging 100 cars a day. (Far, far fewer than an equivalently-sized gas station. If we're going to transition to an electric-only transportation infrastructure, then car changing stations are going to become a common sight) That's 9 megawatt-hours a day. A random solar panel calculator I found guesses that would need ~2000KW of solar panel capacity. So you'll need 8,000 250 watt panels. That'll cover 9,600 square metres, (2.6 acres-- if you're lying them flat, which you won't. A big dedicated solar generation station will use tilted one-axis tracking, which will use a lot more ground space) and cost you (at $410 a panel) a cool $2.4 million. (Google's big solar installation at Mountain View, the one that got so much press, was only 1700KW. Our tiny electric car charging station has to be 17% bigger than it.) Electric car charging uses a lot of power. Solar is great, I love solar, but it's not space-efficient, or cheap. Either Tesla is going to build a national solar generation network on the scale of Germany's move into solar power, all on their own dime, or they're lying through their teeth about charging draw/solar production breakeven.
- schiffern 14y ago
  Yes, in a couple years there will be more electric cars, but solar power installations are getting less expensive every year. I don't know how long until there are enough electric cars to need "Germany-sized" solar installations, but when they do they'll pay a lot less than Germany did. I don't think Elon Musk would green-light the "100% solar power" line without doing the math. Again: you can argue about whether he's lying, but I can guarantee you he knew exactly the scale of what he was promising. That makes it all the more impressive, imo. Re:lying, I'm imagining at some point they'll transition over to "we buy 100% solar power for SuperChargers", which is fine by me since it's functionally equivalent to what they're doing now.

eps 14y ago

So you are basically saying that Musk is lying. This doesn't sound too much like him, does it? A simpler explanation would be that he's not telling the whole story, and that perhaps they have dedicated solar farms in development/deployment or something to that effect. Don't afraid to dream a little bigger, darling.

warfangle 14y ago
Sure doesn't sound like him. He's headed up the first company to commercially resupply the International Space Station, for pete's sake. You bet your ass he quadruple checked those numbers. I'm guessing that the supply at these stations will be much higher than the demand for charging, so they'll make up the cost of "free" by selling wh's back to the grid.