View Single Post
Old 12-22-2017, 09:42 PM   #58 (permalink)
roflwaffle
Master EcoModder
 
roflwaffle's Avatar
 
Join Date: Dec 2007
Location: Southern California
Posts: 1,490

Camryaro - '92 Toyota Camry LE V6
90 day: 31.12 mpg (US)

Red - '00 Honda Insight

Prius - '05 Toyota Prius

3 - '18 Tesla Model 3
90 day: 152.47 mpg (US)
Thanks: 349
Thanked 120 Times in 79 Posts
Quote:
Originally Posted by Hersbird View Post
But the battery is really has a poor amount of energy storage compared to the weight. A Tesla battery weighs what, 1200 pounds? That's 150 gallons of gas or on the other side a Tesla's 300 mile range would only require 8 gallons of gas or 65 pounds of fuel in a under 30 pound container, under 100 pounds total. That's what makes a great mobile source of energy, lots of energy in a light weight.
That sounds right. I think the Model 3 Long Range battery pack weighs a little under 1000lbs for about 65-70kWh of energy that can be put to the pavement, so the energy to weight ratio isn't great compared to gasoline/diesel, which only needs ~85lbs to deliver the same 65-70kWh (lower weight, but also lower efficiency).

At the same time, the power to weight ratio of an electric motor/diff is far higher than an ICE. The Model S drive unit is I think 300+lbs, and I imagine the Model 3 drive unit is around 250+lbs. A RWD ICE with similar power output/tractability is I think around 900lbs.

While the EV drive unit + battery is still a few hundred pounds heavier, some of that can be offset by needing less in the body for rigidity, and the end result is that the curb weight/performance/range of an EV can be pretty close to that of an ICE for higher power cars, eg a Model 3 compared to a BMW 3 series. That gap is much larger with small displacement cars because the engine/trans can weight half as much and they get better mileage, so the range on something like a Leaf is much lower than a Versa or similar.
  Reply With Quote