Quote:
Originally Posted by oldtamiyaphile
...The US grid is 90% efficient, your charger is 90% efficient, the batteries under charge are 80% efficient, the batteries under discharge are 80% efficient, the inverter is 90% efficient, and the motor is 80-90% efficient. As high as each of those number is, those small inefficiencies do add up. You get 37% based on those numbers.
Even if you use best case scenarios (these numbers don't exists outside a lab as inverters/chargers/motors are most efficient under load while batteries are least efficient under those loads) of 90%, 95%, 90%, 90%, 95%, 90%. The EV is only 60% efficient. The Prius ICE is 40% efficient but that doesn't include energy recaptured via braking....
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Sorry, no, the ev efficient is not 60%.
My last charger have 96% efficienty
My Lithium cells have about 7% losts in charging/decharging
Inverter and motor have more then 90% efficienty except at low speed or low power.
So efficienty from the plug to the transaxle is
more then 80% (0.96*0.93*0.90)
A prius have losts between the engine and the output of the transaxle where is connected MG2: a part of the energy go via gears, and the rest via MG1+inverter+MG2. So 40% is the engine alone. Global efficienty depend most upon the % of electrical path. Hypermilers are able to find some sweet spot where the losts are only 5-10%. But at low speed and at hight power the losts are really more. At low power the engine don't have 40% efficiency. When engine is cold it is also true.
Unlike I have read a prius plug-in can be more efficient then a non plug-in.
One of the reasons are the cells; They have much less internal resistance. So better efficiency. During a longer time, there is less need to derate them. May be except in very cold weather.
One other reason is that the factory nimh battery is small and you can have more energy to regen then it is abble to get.
So being more heavy because heavier battery is not necessary bad efficiency.
Here, in France, driving a prius plugin in ev mode release much less COČ and is much less expensive. But this depend upon your country. You may have solar cells ...