Billions in U.S. solar projects shelved after Trump panel tariff

Sig said:
Let me ask you an honest question. If you have an industry that makes a relatively raw product that creates 100 jobs, and and industry that primarily uses that product that has 1,000,000 jobs, would you advocate for losing half of the million jobs to get the 100 manufacturing jobs?

That's exactly the case with things like steel and solar panels. Building solar panels is largely automated and involves very few jobs. It also involves almost no profit, so not even the companies making solar panels, regardless of where they are in the world are making much money. Installing those panels, on the other hand, is very labor intensive. And it's almost entirely trades and unskilled labor. You're advocating for losing thousands and thousands of jobs to possibly create a handful. Plus make electricity more expensive for everyone. How does that make any sense at all, especially given your comments on the need for jobs?
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Sig.... Is this accurate?

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Electric Car Efficiency:

oil to electricity 35% -> transmission line 90% -> battery charging 85% -> battery discharging 85% -> through electric motor 85%.
So the potential energy in oil goes through:
0.35 * 0.90 * 0.85 * 0.85 * 0.85 = 18% efficiency to get through the electric motor
18% of the energy in a barrel of oil makes it through the electric motor.
Gas vehicle Efficiency:

oil to gas 90% -> transportation 95% -> through engine 40%
34% of the energy in a barrel of oil makes it through the gas engine.
Diesel vehicle Efficiency:

oil to diesel 90% -> transportation 95% -> through engine 55%
47% of the energy in a barrel of oil makes it through the diesel engine.
Relative energy output out the motor/engine in barrels of oil:

(this is relative mechanical energy at the output of the engine/motor needed to do the same work (produce the same amount of mechanical energy)) (which is simply the inverse of the efficiency times barrels of oil)
Electric Car: 5.5 barrels
Gas Car: 2.9 barrels
Diesel Car: 2.1 barrels

All these vehicles will go the same distance but the electric car uses around twice as much oil to do it.
Please note that light duty diesel cars and trucks in the US which use the SCR/DEF pollution control system are basically zero emission. (VW did not use the SCR/DEF system)

When electric cars make sense

Electric cars make sense if you are running them on hydro, wind, solar or nuclear.
If you are going to run your electric car on oil, coal, or natural gas, you and the environment are far better off with a diesel vehicle.
 
vanzandt said:
Sig.... Is this accurate?

________________________
Electric Car Efficiency:

oil to electricity 35% -> transmission line 90% -> battery charging 85% -> battery discharging 85% -> through electric motor 85%.
So the potential energy in oil goes through:
0.35 * 0.90 * 0.85 * 0.85 * 0.85 = 18% efficiency to get through the electric motor
18% of the energy in a barrel of oil makes it through the electric motor.
Gas vehicle Efficiency:

oil to gas 90% -> transportation 95% -> through engine 40%
34% of the energy in a barrel of oil makes it through the gas engine.
Diesel vehicle Efficiency:

oil to diesel 90% -> transportation 95% -> through engine 55%
47% of the energy in a barrel of oil makes it through the diesel engine.
Relative energy output out the motor/engine in barrels of oil:

(this is relative mechanical energy at the output of the engine/motor needed to do the same work (produce the same amount of mechanical energy)) (which is simply the inverse of the efficiency times barrels of oil)
Electric Car: 5.5 barrels
Gas Car: 2.9 barrels
Diesel Car: 2.1 barrels

All these vehicles will go the same distance but the electric car uses around twice as much oil to do it.
Please note that light duty diesel cars and trucks in the US which use the SCR/DEF pollution control system are basically zero emission. (VW did not use the SCR/DEF system)

When electric cars make sense

Electric cars make sense if you are running them on hydro, wind, solar or nuclear.
If you are going to run your electric car on oil, coal, or natural gas, you and the environment are far better off with a diesel vehicle.
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TLDR, no, while that may be correct in one scenario, that scenario doesn't exist in a meaningful way, so it's not accurate.

So first off, your average diesel engine efficiency is less than 45% efficient. When you do the math train on that you get .9*.95*.45=38.5%
The efficiency of a combined cycle gas plant, which is the marginal producer of electricity in most of the U.S. today, is 62%. Transmission losses according to EIA are on the order of 5%, so that it 95%. I know the Tesla powerwall advertises 92% round trip efficiency, let's assume 90% for the car pack. Electric motor efficiency is around 90% for electric cars. So .62*.95*.92*.9=51%

You can obviously shade the numbers on a bunch of those to try to make a point. I think the bulk of the inaccuracy in the numbers you had were because someone was trying to make the rather obtuse point that if you burned diesel fuel in a power generation plant and used that to power an electric car it would be less efficient than using that same diesel fuel to power a diesel car. That's intellectually dishonest given that 0.3% of U.S. electricity is produced by liquid petroleum products, and that's really just backup power used in dual fuel plants that have supply interruptions (https://www.eia.gov/tools/faqs/faq.php?id=427&t=3).

The real benefit transportation electrification provides is access to the efficiency of combined cycle gas (which you could never fit in a car/store/transport...) to the transportation sector. Plus obviously other efficient generation as it comes online and existing nuclear and hydro, but with today's mix it's really that combined cycle gas efficiency that's providing the majority of the value.
 
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