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How do you determine how much electricity is needed to supply an elec. E.V. motor w/ say 100 H.P. to propel a vehicle- 1800#, @ a constant 60 M.P.H.? .....And yes, I'm a newbie.
 

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My personal favorite method is to click on the "Garage" tab at the top of the page. It will show members cars and by clicking on the "Show" button to the right of that list, it shows a variety of specifications of members cars. Top speed and range are often listed.

This method allows you to guesstimate what the car you want to convert will be capable of, using a similar vehicle and components. No guarantees, but it should put you in the ballpark.
 

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How do you determine how much electricity is needed to supply an elec. E.V. motor w/ say 100 H.P. to propel a vehicle- 1800#, @ a constant 60 M.P.H.? .....And yes, I'm a newbie.
There are two different questions there.

Question 1:
How much electricity needed to supply a 100hp motor?

100hp = 74600Watts
Given Watts = Volts x Amps
Say the battery pack was 144Volts then you would need 518Amps to achieve 100hp.
You would need to factor in losses.

Question 2:
How much power is needed to propel a 1800lbs vehicle to 60mph?

That would depend a great deal on the aerodynamics of the vehicle and the rolling resistance and a few other factors.
Given assumptions:
Weight 1800lbs (817kg)
Cd 0.35
Frontal area 1.5sqm
Speed 60mph
Air density 1.292
Rolling resistance 0.03

Using my simple spread sheet:
Power to overcome aero drag 6545W
Power to overcome rolling resistance 7113W
Total power to maintain 60mph 13658W (18.3hp)
Energy consumption 228Watts per mile

There are EV calculators around that can help you enter more details to get a better idea of what you need.
 
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