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I have noticed in various discussions that many people are using incorrect units when talking about energy and power. This can be confusing, making the post more difficult to read. Energy is kilowatt-hours (kWh) and power is kilowatts (KW). Because these terms are so much alike, they often get used incorrectly; possibly just typo's.

When talking about ICE vehicles, it is incorrect to say the gas tank holds 15 horsepower, or the engine produces 200 gallons. If I said either of these in a post, people reading it would immediately dismiss me as an idiot. Fortunately, horsepower and gallons are such different terms, nobody would every use them interchangeably.

The battery pack in the Bolt is 60kWh. The motor controller can produce 150KW (although I saw the display on mine show 157KW yesterday). The charger in the Bolt is 7.2kW. If you run it for an hour, it will add 7.2kWh back into the battery pack. This assumes you have an EVSE (Electric Vehicle Service Equipment) that can supply 7.2KW (that is 30A at 240V, or 32.7A at 220V) and there are no losses.

Ed
 

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The instantaneous power display you saw was likely due to inefficiencies in the motor's speed controller. The motor will produce 150kw but there will be efficiency losses turning electricity into kinetic energy. I wouldn't be surprised if in order to get 150kw out of the motor the system would have to dump in at least 175. I've been meaning to notice the max draw I can get on a full "throttle" pull, but I suspect you need the planets to align for the system to give you full power, between the battery at the right temp and 100% SOC, adequate grip on flat ground that traction control doesn't cut in etc... I'm still trying to find the formula on exactly what contributes to how much jam the car has when I get on it, so far I'm noticing a big difference on SOC obviously, but also ambient temp and how long I've been driving the car in colder weather (giving the pack a chance to warm up a bit).
 

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I would say neither the motor not the motor controller can produce 150 kW of power. If anything can, it will be the battery.

At best, the motor and motor controller are capable of delivering, handling or converting 150 kW of power. But not producing ;)
 

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I would say neither the motor not the motor controller can produce 150 kW of power. If anything can, it will be the battery.

At best, the motor and motor controller are capable of delivering, handling or converting 150 kW of power. But not producing ;)
Ok fair enough. But if you want to go there then you'd also have to say that battery cannot produce the energy, it can only store it, again with its own efficiency losses ;)
 

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It will take time before people understand the difference between the two. I had to dispute a PGE bill once and many people there didn't understand what a kWh was or even how their tiered system worked. I even say gas pedal still... A kW is 1000 Joules of energy being used per second. Our motor is 150,000 Watts and you can divide it by about 746 (1 HP = 746 Watts) to get our 200 HP. But get used to the mistakes since the majority of people can't read their power bill, which is really their energy bill :laugh:
 

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Ok fair enough. But if you want to go there then you'd also have to say that battery cannot produce the energy, it can only store it, again with its own efficiency losses ;)
Dude, this is your game, stay focussed ... ;)

Indeed, the battery doesn't produce energy, it stores it. But it uses the energy it has stored to produce (electrical) power, which is what I said. Likewise, the motor consumes power and delivers it to the wheels by producing torque.

Question is: who or what produces energy? E = MC2, so perhaps the answer is matter? :nerd:
 

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The charger in the Bolt is 7.2kW. If you run it for an hour, it will add 7.2kWh back into the battery pack. This assumes you have an EVSE (Electric Vehicle Service Equipment) that can supply 7.2KW (that is 30A at 240V, or 32.7A at 220V) and there are no losses.

Ed

it's more like 6.5kw added back to the battery ... there is about a 10% loss on the way ... but then i'm not an expert with kw, kwh and electricity ;)
 

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I have noticed in various discussions that many people are using incorrect units when talking about energy and power. This can be confusing, making the post more difficult to read. Energy is kilowatt-hours (kWh) and power is kilowatts (KW). Because these terms are so much alike, they often get used incorrectly; possibly just typo's.

Ed
Actually the use of kilowatt-hours is also wrong, because the correct term for energy is the Joule. One joule is one watt-second, so a watt-hour is 3.6 kilojoule or 3.6 kJ, and a kWh is 3.6 MJ.
 

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Dude, this is your game, stay focussed ... ;)

Indeed, the battery doesn't produce energy, it stores it. But it uses the energy it has stored to produce (electrical) power, which is what I said. Likewise, the motor consumes power and delivers it to the wheels by producing torque.

Question is: who or what produces energy? E = MC2, so perhaps the answer is matter? :nerd:
All the energy on this planet came from the Sun. It was mostly stored as chemical energy in petroleum (from vegetation) or in coal. And these are consumed to release that energy as heat first. Only photoelectric is the more direct and renewable source of electrical energy. Wind energy comes from thermal conversion of solar energy in the atmosphere, and tidal energy comes from the gravitational effect between the Earth and the Moon (and both came from the Sun). And you final answer is indeed matter in the Sun (fusion).;)
 

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The Earth and Moon did not come from the Sun, it came from condensing and accretion during the creation of our solar system according to the solar nebula theory. Be careful with the word all, because we get energy from other stars as well, but I wouldn't build a solar panel to collect that energy... We also have dark matter and energy all around us, which makes up about 96% of the universe according to our current calculations.

Even though Joules are the SI MKS unit for energy, you can use any unit you want since they all can be converted to each other. I could use mass in slugs, acceleration in km/s^2, and height in rods to make my own energy unit called a Dan. It would be a valid energy unit because I could convert it to J or kWh.

Most Bolt users are not physicists or engineers and will make many mistakes in describing this new technology. Most people just autopay their electric bill without even reading it. Ohm's law is not very difficult, but I would not expect many people to really understand it here. If you charge your electric car in your house at standard electric cost, it is about the same as driving a Prius mpg or mpkWh. However, we have a Prius that can do the 0 to 60 mph in about 4 seconds faster. Even with the horrible seats, I could not drive a Prius over a Bolt.

That 10% loss was correct in the past, however I was reading that new chargers only have about a 4% loss. So it needs to be factored in, but the technology is really helping out EV's. I am going to do a write-up about the real cost of comparing mpg to and EV. The numbers of 120 mpg equivalency is not correct with tiered electric systems or taking into consideration buying a charger that costs about $1000 to purchase and be installed. I am addicted to EV's and I could never go ICE or even hybrid ever again...
 

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The Earth and Moon did not come from the Sun, it came from condensing and accretion during the creation of our solar system according to the solar nebula theory.
...and geothermal energy comes from the Earth's internal heat, which is a remnant from when it condensed from that nebula.
 

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That 10% loss was correct in the past, however I was reading that new chargers only have about a 4% loss. So it needs to be factored in, but the technology is really helping out EV's. I am going to do a write-up about the real cost of comparing mpg to and EV. The numbers of 120 mpg equivalency is not correct with tiered electric systems or taking into consideration buying a charger that costs about $1000 to purchase and be installed. I am addicted to EV's and I could never go ICE or even hybrid ever again...

from 59% to 81% 14.6 kwh delivered, 22%=13.2 kw, 1.4kw=10% loss (DCfast)
from 14% to 40% 17.4kwh delivered, 26%=15.6 kw, 1.8kw=10.4% loss (DCfast)
from 11% to 89% 51kwh delivered, 78%=46.8 kw, 4.2kw=8.3% loss (51kw delivered in 8hrs45mins)


efficiency seems to be slightly better with the "slow charger" but still over 8% loss
 
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