Comments on: A Brief Electric Vehicle Geek Out

By: How Charged Up Is Your Battery? | Israellycool

How Charged Up Is Your Battery? | Israellycool — Fri, 08 Mar 2013 08:21:48 +0000

[...] By comparison, Oscar’s percentage or kWh readout drops in a predictable linear way depending on the terrain and the speed and most owners get used to this. Oscar even takes this further and predicts your state of charge at a destination including taking up…. [...]

By: amir

amir — Fri, 22 Feb 2013 05:46:24 +0000

The battery display turns orange when it hits 12% capacity. Also the Oscar route calculator will not include stops, such as batttery switch stations, if it estimates that you will arrive with 12% battery or less. This margin of error, IMO, is too large, and prevents OSCar for calculating the most efficient routes. I was told (by someone who I believe no longer works at BP) that the margin of error on the new OSCar will be smaller.

By: Brian of London

Brian of London — Thu, 21 Feb 2013 13:41:01 +0000

There is definitely a reserve below 0% on the display but, much as 100% is registered before the battery is really full, I suspect that the kWh display will show a kWh or so when the percentage reads 0%. By all accounts you have 6 to 8 km once it tells you 0%.

By: Brian of London

Brian of London — Thu, 21 Feb 2013 13:37:43 +0000

You are completely correct. I’ve fixed the post.

By: Eric

Eric — Thu, 21 Feb 2013 12:29:33 +0000

I’ve been told that in a gasoline powered auto, the fuel needle hits “E” when the tank is 90% empty (that is, you still have 10% of the fuel in reserve). I wonder if they do they build in the same margin of error in the Oscar software? Or is zero really zero?

By: Robin

Robin — Thu, 21 Feb 2013 10:30:07 +0000

I may be wrong, but I don’t think the “0kW” reading is an abbreviation of “0kWh”, it’s not kilowatt-hours, just kilowatts.
Kilowatt (kW) is a unit of power, used to quantify immediate power, as in “right now the car is drawing 20 kilowatts from the battery”.
Kilowatt-hour (kWh) is a unit of energy, used to express capacity, “this battery has a capacity of 22 kilowatt-hours”, which means “this battery can deliver 22 kilowatts of power for 1 hour.”
The unit is literally defined as kilowatt x hour.