80% of your gas money goes out the tailpipe
80% of your gas money goes out the tailpipe
Key context: thermodynamics dictates that heat engines waste a lot of energy.
Credit: Karin Kirk
It's even worse when you take a bunch of the small percentage of energy the heat engine successfully turns into motion and then use it to heat up the brake discs.
Being able to recapture kinetic energy into a battery and reuse it later helps overall efficiency a lot.
Plug-in hybrid? Aren't they worse than both, because of the weight of motor and battery?
You also get to use a smaller lighter ICE motor which is augmented by nearly instantaneous electric power. My favorite car was a Prius C which is no sportscar, but feels much zippier than you would expect for getting 50 mpg.
Series plug-in hybrids that can run on battery (Chevy Volt, Honda Clarity, Prius 2024) are IMO better than both. They effectively operate like electric vehicles (regenerative braking and all), and one can drive them for months without burning gas. Their batteries are about five times smaller (~30-50mi range vs full EV's ~250mi range), and thus lighter, and the gasoline engine is usually a small, efficient one (~40ish mpg on gas)
Yes, unless your only metric is fuel consumption or range with a given tank. Then they're pretty strong.
Only 70% going out the tailpipe.
Well-To-Wheel energy efficiency:
Gasoline: ~20%
Diesel: ~30%
H Fuel Cell: ~25%
BEV (fossil power): ~20%*
BEV (renewable): ~55%**BEV is highly dependent on energy source. Anwhere from ~20% WTW from natural gas power generation to 75% from roof-mounted solar.
Keep in mind this is a summary of a summary of a summary.
Sources:
- https://www.researchgate.net/publication/344860096_Comparison_of_the_Overall_Energy_Efficiency_for_Internal_Combustion_Engine_Vehicles_and_Electric_Vehicles
- https://c2e2.unepccc.org/wp-content/uploads/sites/3/2019/09/analysis-of-hydrogen-fuel-cell-and-battery.pdf
- https://yaleclimateconnections.org/2022/08/electrifying-transportation-reduces-emissions-and-saves-massive-amounts-of-energy/
Technically solar panels are only ~20% efficient, but there's also virtually unlimited sun so it doesn't really matter.
Scotland disagrees
I think the 80% number is outdated (although most of the energy is still wasted)
F1 engines achieve a peak thermal efficiency above 50 percent, significantly higher than a modern passenger car's 35 percent thermal efficiency - https://www.motor1.com/news/655596/video-how-f1-engines-make-1000hp/
So more like 65% goes out the tailpipe...
If your rolling coal, you are literally pumping unused diesel fuel out the car. You're efficiency is absolute dog shit.
When people realize that heat is actually energy and not just some free byproduct :o