The next question is how many kW will these gas engines produce to power the EV car (charge the battery)? Let's say we're getting 2 miles / kWh while driving 80mph down the highway. That means we're consuming 40 kWh in an hour. Will the gas generator in the car provide at least 40kW of power to keep us going indefinitely? Maybe a 4-cyl engine can do that. If not, then the car will still be very dependent on the battery for long trips, and the article says they're looking at 60 miles on battery alone.
If the engine can produce at least 40kW of power to power the motors and charge the batteries, then it'd be a practical car for most people. For local driving, the 60 mile range on battery alone would save a lot on gas (use up practically no gas for local driving while adding only a little to your power bill), while on long trip driving you don't have to stop to recharge every 200 or so miles like in a BEV.
“Will the gas generator in the car provide at least 40kW of power to keep us going indefinitely? Maybe a 4-cyl engine can do that.”
40 kw is 54 hp.
“The next question is how many kW will these gas engines produce to power the EV car (charge the battery)? Let’s say we’re getting 2 miles / kWh while driving 80mph down the highway. That means we’re consuming 40 kWh in an hour. Will the gas generator in the car provide at least 40kW of power to keep us going indefinitely? Maybe a 4-cyl engine can do that. If not, then the car will still be very dependent on the battery for long trips, and the article says they’re looking at 60 miles on battery alone.”
Modern GDI turbo engines can make 200+ hp per liter of displacement. Even naturally aspirated GDI engines make 100hp per L or more. It’s how high do you want to spin them up motorcycle 1000cc engines easily exceed 100hp per liter.
So a 1.5 liter engine is a 100-150hp naturally aspirated or 300+ with boost they show in this very article they can get 600hp out of 2 liters with boost that’s 300hp per L.
740 watts to a HP so 100hp is 74 kilowatts <<< this is triple what a 5 passenger sedan needs to cruise at 80mph.
I have a model 3 Tesla it is identical in size down to the inch in shadow footprint to the Volvo S60 it replaced. It’s 200lbs lighter in curb weight vs the T5 AWD S60 I know EVs are too heavy right uh nope. It also rides on identical Pirelli tires 18” rims I bought 8 and had a buddies tire shop install them so yeah no special EV tires needed at all just Z rated quality Italian rubber.
At 80mph that Tesla with the A.C. On is using 280 watt hours per mile. That’s 22.4 kilowatt hours per hour which is 30 horsepower this is exactly what a similar size and mass sedan would need to move it at 80mph.
For a 5 passenger sedan 1.5 liters is too big you would get better BSFC overall with a 1 liter 3 cyl running at 30-50hp at 75% of max torque which is where the OTTO cycle reaches its peak eff point and it’s lowest BSFC per kw produced.
Remember the 82,000lb Tesla Semi only needs 1700 watt hours per mile to move it’s DOT gross maximum mass at highway speeds and suburban delivery routes PepsiCo has mountains of data from their in the field real world testing in hills and valleys in California at that. 1.7kWh per mile at 65 mph is only 110kw a 1.5 turbo can do that all day long the 2.0T wouldn’t even be working hard to pump out 150kw.
Once you have a battery pack for peak loads and regenerative braking energy recovery which doubles your urban MPG as is evident by the ICE Camry vs the Hybrid of the same year the 2024 is the last model’s you can compare and the Hybrid more than doubled the pure ICE mpg in the city. You size your generator for the average load at the max continuous speed you desire. Toyota is putting in a generator of a size that you could do 120+ mph continuously. There is no need for 100+kw in a range extender you need 50kw at most to cruise at a steady 100mph, 85 is only 23kw the power to overcome air drag goes up at the cube root of speed. Nowhere in North America is it legal to drive 100mph the 85mph speed limit tollway was reduced to 80 after a few years and some fatality wreaks even West Texas has a 80mph limit and only in like three very rural counties.
BYD has the Seal QI with this type system already in it. It’s a overexpanding OTTO cycle with VVT and different compression ratios vs expansion ratio using both intake and exhaust valve VVT plus phasing too. The Qi has a pack sized to go 75 miles before the engine kicks on to charge the pack back up. A group of Chinese journalists not professional testers took on for a 1300 mile drive through one of China’s megacities they drained the pack to zero on purpose then let the engine run only to charge the pack back up then ran the pack down again to zero, and again charged it up, and on and on till the gas tank ran empty then they ran the pack to zero. They covered 1300+ miles before the car came to a halt it was returning 2.2L per 100km that’s 106.9 miles per gallon American. How? Because the Chinese designed that little generator to run at its peak eff point and it’s lowest BSFC only to charge the pack at a rate that exceeds the average moving amp draw and then some. They hit 48% BSFC at the flywheel and 42% electrons to the pack it’s a world’s best in both categories. The Prius comes close and can also return 93mpg cross country distance a guy did exactly that he took a Prius coast to coast and averaged 93 mpg setting a record for it officially.
^^^^this is the future Toyota knows it and BYD is already kicking butts and taking names. One electric drive platform feed by any source of high voltage electrons in the 400-1200V range the EDU in the axles don’t care if those electrons come from a lithium ion, sodium ion,aluminum ion pack or from a high speed high voltage AC axial flux generator that is 20kw per kilogram in mass ratio feed into silicon carbide rectifier/inverters the EDU simply doesn’t care, you could just as easy spin a microgas turbine and a turboalt at 400-4000hz a paint can sized turbo alt is 170kw that you can hold up in one hand.
Point is modern electronics and electrical engineering into motors has advanced well past anything mechanical transmissions can do. 20+kw per kilogram in motors which are all automatically triple phase AC generators by physics. The silicon carbide inverters and axial flux induction is The key. Gas turbines struggle to hit 6:1 mass ratios ICE is less than 1:1 kw to kilogram even turbo GDI race engines only hit 2:1 or 3:1 that’s an order of magnitude off from 20:1 for electrons. Yes batteries are heavy but you don’t need much mass for a plug in hybrid pack of 10-20kWh that can dump 10C @ 200kw in miliseconds for peak loads. Even less mass for a Prius sized 1.5kWh hybrid pack it for a under a seat no literally thats where they put it. LFP cells can do crazy amp dumps and the next gen aluminum ion can do 66C charge cycles with 20000+ cycle life’s to 80% SOH.