Teardown reveals Chevy Volt's electronic secrets

[Christ]

Originally Posted by mechman600

Coal powered electric cars still produce 21-58% less CO2 than gasoline powered equivalent cars, according to this:
Greenhouse gas emissions

Efficiency. ICEs are 25% efficient on a good day. EVs are 80%+ efficient. A bad fuel source (coal producing electricity) with good efficiency becomes good, or at least decent, doesn't it?

Hydrogen? Horrible. 6X the CO2 of an ICE when the hydrogen is produced from natural gas, which is most hydrogen. When it's not derived from natural gas, it comes from lots of electricity + water. Where does the electricity come from? Wait for it.......COAL.

The motor in the car is 80% efficient, sure. How efficient is the power station, the power station's fuel extraction/transportation methods, etc?

[user removed]

Originally Posted by euromodder

The plane got wet ... seriously.

Moisture in the AoA sensors caused the far too steep initial pitch up.

Andersen Air Force Base B-2 accident - Wikipedia, the free encyclopedia

Seriously, and some overlooked moisture effects just confiscated the total net worth of 1.4 million millionaires (worth a cool 1 mil each).

A little moisture seriously . I find such simple analyses to be absolutely astounding considering the vast amounts of capital expended to create the ultimate weapon.

Fogged up sensors!

And you wonder why I have serious reservations about complexity in individual transportation modules that are designed by human beings.

jezus
Mech

[user removed]

Best motor is the 5 cylinder Audi at 43%. Best IC engine pushing 56%. Best natural gas power plant turbine turbine with exhaust heat recovery additional generation is pushing 60-65%.

Make your comparisons realistic, like Christ suggested and include every sequential loss. You know like transmission losses. Jesus the Leaf only got 85% of the metered energy in the battery.

I guess the new reality will be if you ignore enough facts and omit relevant information, then your newly redesigned facts become facts in and of themselves.

How novel a thought process, lets ignore reality, physics, and Carnots Law while we are at it.

regards
Mech

[IamIan]

Originally Posted by Christ

The motor in the car is 80% efficient, sure. How efficient is the power station, the power station's fuel extraction/transportation methods, etc?

It will vary from plant to plant ... but if it is a modern co-generation power plant ... about ~80% Energy Efficiency... and they pollute less per wh of energy output.

Although ... the Electrical power plant is effectively the 'refinery' for the source to output electricity ... to include the power plant 'refinery' losses one should also include the 'refinery' losses to get the gasoline... to be fair anyway.

If you want to compare transportation costs ... and efficiencies ... a lot of energy is spent shipping / pumping / etc that gasoline ... In general I suspect that the transportation from source to load energy wh output is significantly better for electricity than gasoline to get the same wh of energy output at the load over the same distance.

Almost all industrial / commercial facilities I know of use electrical motors for HVAC ... for Beam Saws ... for CNC Machines ... assembly lines ... etc ... not because a gasoline or diesel ICE couldn't be built to do the job ... but because the ICE can not come even remotely close to being as cost effective to produce the same Wh of mechanical work energy done at the load.

The only reason I see the transportation has lagged behind ... is due to the 'range' issue of energy storage for a given amount of weight... for this Fuels like Gasoline with very high energy densities can be effective ... but that singular benefit only goes so far for all the other negatives / compromises it has.

[Christ]

Originally Posted by Old Mechanic

Seriously, and some overlooked moisture effects just confiscated the total net worth of 1.4 million millionaires (worth a cool 1 mil each).

A little moisture seriously . I find such simple analyses to be absolutely astounding considering the vast amounts of capital expended to create the ultimate weapon.

Fogged up sensors!

And you wonder why I have serious reservations about complexity in individual transportation modules that are designed by human beings.

jezus
Mech

I think you mean 1.4 THOUSAND millionaires, sir.

[Christ]

Originally Posted by IamIan

It will vary from plant to plant ... but if it is a modern co-generation power plant ... about ~80% Energy Efficiency... and they pollute less per wh of energy output.

Although ... the Electrical power plant is effectively the 'refinery' for the source to output electricity ... to include the power plant 'refinery' losses one should also include the 'refinery' losses to get the gasoline... to be fair anyway.

If you want to compare transportation costs ... and efficiencies ... a lot of energy is spent shipping / pumping / etc that gasoline ... In general I suspect that the transportation from source to load energy wh output is significantly better for electricity than gasoline to get the same wh of energy output at the load over the same distance.

Almost all industrial / commercial facilities I know of use electrical motors for HVAC ... for Beam Saws ... for CNC Machines ... assembly lines ... etc ... not because a gasoline or diesel ICE couldn't be built to do the job ... but because the ICE can not come even remotely close to being as cost effective to produce the same Wh of mechanical work energy done at the load.

The only reason I see the transportation has lagged behind ... is due to the 'range' issue of energy storage for a given amount of weight... for this Fuels like Gasoline with very high energy densities can be effective ... but that singular benefit only goes so far for all the other negatives / compromises it has.

Ok, so forgetting the extraction and transportation issues... you have an 80% efficient motor using fuel from an 80% efficient source, transmission losses equaling ~7% average across the grid.

So now you've got 80% of 93%, or 74% efficiency, then a motor which is 80% efficient using 74% of the original energy source - 59 percent efficiency, not counting losses via the chargers. High power inductive chargers are ~86% efficient. So now you're looking at 51% efficiency in the long run, and that's provided everything is working absolutely correctly.

To be fair, liquid fuel is trucked along and pumped repeatedly, which costs in it's efficiency calculations, as well.

Point being, to say that electric cars are 80% efficient is fallacious when you don't consider the other factors involved, just as it is fallacious to say that gasoline cars are X efficient while only looking at the energy extraction phase.

[jamesqf]

Originally Posted by IamIan

It will vary from plant to plant ... but if it is a modern co-generation power plant ... about ~80% Energy Efficiency... and they pollute less per wh of energy output.

In addition, only about half of US electric generation is from fossil fuels, which means that WRT CO2 & other emissions, the efficiency is effectively doubled.

[user removed]

Originally Posted by Christ

I think you mean 1.4 THOUSAND millionaires, sir.

Yep, I guess I was thinking about the National debt, which currently (if you believe their numbers) is 16,000,000 millionaires.

regards
Mech

[NeilBlanchard]

Electric motors are up to 94% efficient. Plug to wheels is about 85% efficient. Single speed reduction gears used on some EV lose about 2%, which is included in the plug to wheels number.

IC engines are up to 38% efficient for gasoline (Prius) or ~42% for some diesels. Transmissions and clutches/automatics have some losses -- maybe 5-7%?

If you want to add in source to car losses for EV's, then you have to add them for liquid fuels, as well. But remember that if you have solar PV on your roof, or if you pay for renewable-generated electricity, then you only lose about 8% for grid losses. Oil is getting harder and harder to get -- the numbers on tar sands bitumen for example is the equivalent of about 1:2 for the resulting energy. If that is worth it, then we have passed peak oil.

As the oil runs out, then we will have to use renewable energy more and more. Renewable energy will last as long as the earth does -- about another 5 Billion years.

[jamesqf]

Originally Posted by NeilBlanchard

IC engines are up to 38% efficient for gasoline (Prius) or ~42% for some diesels.

But remember that in current automotive applications, the IC engines are almost never running anywhere near their max efficiency. See various threads re BSFC.