• 0 Posts
  • 11 Comments
Joined 2 months ago
cake
Cake day: August 24th, 2024

help-circle


  • Putting a solar roofs over any open-air carpark you happen to own is just a hilariously easier option. Hell, you could erect these OVER the train tracks.

    https://greenox-group.de/photovoltaik-carport/ (Article is in German, but it’s really more around the picture)

    According to a completely un-sourced picture I found online, one carpark (in the USA) is typically around 5.5 x 2.6m, so if you had even 50 carparks on your site you could have ~715 square metres of panels. More, if you figure a way to cover the aisles between the rows of carparks too.

    At the top end of all applicable figures (panel efficiency, solar irradiance, inverter efficiency), that could net you ~160kW at solar midday.

    Now on the other side, standard-gauge railway is around 1.4m wide, and maybe you could cram a 1m width of panels between the rails.

    That sounds like a lot - 1000 square metres per kilometre, and there are thousands of kilometres of railway lines out there - but it’s harder to install, harder to service, gets dirty faster, is liable to get damaged, and now you have to figure out how to extract power from somehing a kilometre long, instead of an area that could be a square only around 35m (~115’) on a side (for the above 50 carparks).

    I know which one of those I’d want to run the cables for.

    As has been pointed out many times when this dumb-ass idea comes up, only once you’ve exhausted every other possibility (carparks, rooftops, putting panels ABOVE roads/rivers/canals/cycleways/railways) and have literally no other viable installation locations, then we can talk.






  • it’s essentially 2 PCI Express x1 lanes and USB 2.0

    Sometimes there’s only a single PCIe lane though. And as you say, that’s not a x2 but explicitly two x1s.

    No WiFi card needs the bandwidth (yet), at PCIe 3 speeds you’ve got around 7.8Gbps for a x1, and PCIe 4 double that.

    The Coral comes in a “dual” version for exactly this reason (https://coral.ai/products/m2-accelerator-dual-edgetpu/) you just have to be very sure the slot you’re putting it in is actually delivering two PCIe connections.

    Also for bonus fun, most WiFi/BT cards use the PCIe interface for the WiFi and USB for the Bluetooth.