|
Compared to ICE vehicles, EVs are expensive and heavy (according to Slate, an F-150 Lightning weighs 35% more than its ICE sibling). Cost and weight reduction are both important factors for any EV maker to optimize. Why do you assume the 12V bus doesn't drive high-power stuff? Historically, every single electrical component in a car is powered at 12V. Everything. Your alternator outputs 12V to both power your electrical system and charge the 12V battery. Even the starter and ignition system (distributor or coil pack) transforms 12V into the high voltages needed for combustion. I'm not exactly sure why 48V corresponds to a decrease in "complexity." My guess is that power and data were sent over separate cables, whereas PoE does everything together. That's just a guess, however. Assuming the same power requirements, a 4x increase in voltage translates to a 4x decrease in current. Looking at [1], a component requiring 8AWG @ 12V can now use 18AWG @ 48V. That's a significant decrease in copper, resulting in cost and weight reductions. A higher voltage is almost always preferred, though the higher electric potential means you need better insulation and safety measures. Though there's a saying that it's current, not voltage, that kills, high voltage is widely known to be dangerous. For example, consider the US electrical grid, which is actually a 240V system, not 120V. Three wires come to your house from the transformer: -120V, 0V, and 120V. A normal outlet is connected to either -120V and 0V or 0V and 120V, and you can get a 240V outlet by connecting to -120V and 120V. This 120V-by-default setup is much safer than 240V every outlet, like in other parts of the world, and you can still get a higher voltage for high-power appliances (e.g. clothes dryer). [1] https://en.wikipedia.org/wiki/American_wire_gauge |
Expensive maybe, IMHO not really, at least in China. Heavy .. this doesn't sound fair. Are you comparing a cherry-picked, heavy, full battery back EV with an empty tank ICE? Noting the EV has far more torque, and that the same tech is used in UAVs and in a ground vehicle you can arguably move the weight around (lower it) easier in an EV, this casual observer (not a car person) would expect superior mass distribution and lower overall weight (certainly vs torque).
500kg solar EV: https://www.unsw.edu.au/newsroom/news/2022/06/sunswift-7--dr... ... compare Toyota Corolla: 1314kg + 50kg fuel / Toyota Camry: 1360kg + 70kg fuel / Tesla Model 3: 1611kg / Toyota RAV4 average: 1634kg + 55kg fuel / Tesla Model S: 2107kg / Tesla Model X: 2458kg / Your cherry-picked example of an F-150 Lightning: 2948kg / Chevrolet Silverado 1500: 3311kg + 105kg fuel / way more heavier ICE cars follow...
Another potential consideration is that the EV is far better placed to use recovered power from braking, so a small amount of additional mass will have less efficiency impact than in a comparable ICE.