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Comment: Re:With the best will in the world... (Score 1) 486

In the example in the article, they are using wind generated electricity to make the fuel. So, the process is...

Electricity -> Synthetic Diesel Fuel -> Combustion -> Power (to wheels of car)

While for an electric car...

Electricity -> Battery Charge -> Battery Discharge -> Electric Motor -> Power (to wheels of car)

So, for the Electricity -> ... -> Power efficiency, on the Roadster Tesla claims to be at 86% efficiency (they call it plug to wheel efficiency). Compare that to the Electricity -> ... -> Power efficiency of the synthetic fuel which I am assuming to be between 10% and 20% ( 70% efficiency for creating fuel * 35% combustion efficiency * probably about 90% mechanical efficiency for transmission and differential).

I am not trying to say that there won't be a place for this technology. I just think that in most circumstances electric cars will be a much better option.

** A normally fueled car usually has a well-to-wheels efficiency of around 14%, so as far as actual energy efficiency goes, this fuel is doing pretty well. It just looks bad next to the high efficiency of electric cars.

Comment: Re:How much energy does it take to produce? (Score 1) 486

It is pretty much guaranteed that charging an electric car takes less energy than this. Internal combustion engines are only ~35% efficient, so even if the process of creating the fuel is 100% efficient (which it is not, it is probably in the ideal case about 50% efficient), you would still need 3x the energy to create the fuel.

Comment: Re:With the best will in the world... (Score 1) 486

Charging batteries is usually very efficient, so this process is probably significantly less efficient. Also, batteries discharge very efficiently, while an Internal Combustion Engine is usually around 35% efficient. I would guess that overall in the ideal case it would be on the order of 10-20% efficient (or less), compared to the roughly 90% efficiency of batteries. But, it is only a guess.

Comment: Re:With the best will in the world... (Score 5, Informative) 486

Normally, diesel fuel is burned thus...

Diesel Fuel + Oxygen -> CO2 + H2O + Energy

So, I would assume the opposite would be...

CO2 + H2O + Energy -> Diesel Fuel + Oxygen

The reason why diesel engines have problems with NOx emissions is because the high temperatures and pressures in diesel fuel cause the nitrogen in the air to react with oxygen. Nitrogen is not normally a component in diesel fuel.

Along the same lines, cars burning this fuel would probably still have NOx emissions.

Comment: Re:Coal power cars make little sense (Score 1) 257

by gtbritishskull (#49068923) Attached to: Tesla Factory Racing To Retool For New Models
I was just commenting on your incorrect view on physics. Yes, torque alone does not matter. The number that does matter is the 0-60, which was 3.2 seconds (for the P85D), 5.9 seconds (for 2012 base) or 5.4 (for the 2013 base). But, according to you that also does not matter. That the only thing that matters is the range. You move from one argument to another, and whenever one argument gets shot down you try another. You are biased against the car (or, more likely, electrics in general) and no matter what I say you will find something else to hate. I could bring up the supercharger network which is being constantly expanded. Or that most people drive less than 30 miles per day. But, you would just move on to your next argument, probably saying that they rank at the bottom because they don't have a trailer hitch. I am done feeding the trolls.

Comment: Re:Coal power cars make little sense (Score 1) 257

by gtbritishskull (#49067405) Attached to: Tesla Factory Racing To Retool For New Models
From reading your comments, I am about 50% sure that you are a troll, but I can't let a comment with such terrible physics interpretation stand without a response. Torque is a force. Force is not energy. Energy comes from work. Work is force times distance. So, you can have as much torque as you want, but if it is not moving no energy is being expended. To follow your tree example, the branches on the tree support enormous torque. But, they are not moving so do not produce energy. I would respond to your other points, but honestly didn't think it would be worthwhile trying to understand what you were saying after I realized you have zero grasp of physics.

Comment: Re:inb4 (Score 2, Interesting) 638

by gtbritishskull (#45280115) Attached to: Drive With Google Glass: Get a Ticket
But, it seems that a low of people are arguing that Glass should be illegal to wear while driving. Is it better to have to look down at your dash to view your navigation than to have it displayed in the corner of your vision? Or, is the argument that it CAN be used improperly (watching youtube, facebook, etc.) so it should be illegal? If that is the argument, then we should ban all guns because they can be used improperly (to kill innocent people).

Comment: Re:Small economics (Score 1) 242

by gtbritishskull (#44543403) Attached to: Looking Beyond Corn and Sugarcane For Cost-Effective Biofuels
Ethanol from sugarcane has an 8:1 energy balance (8 units of energy out for every 1 unit of energy put in). Ethanol from corn was below or less than 1:1, but I think it now has a (barely) positive energy balance due to advances in technology and economies of scale. I think I read that biodiesel was between 2 and 3, but I am sure that depends on what plant you are getting the oil from.

Comment: Re:I find it hilarious... (Score 1) 452

by gtbritishskull (#44319979) Attached to: Tesla Motors May Be Having an iPhone Moment
Oil can be used to make electricity. So can coal, natural gas, sunlight, biomass, flowing water, and wind. When was the last time you saw a wind powered car driving down the road (though this one is pretty neat). Or a coal powered car? Nuclear powered? We do have natural gas powered vehicles, but how difficult would it be for you to use it in your car? We have a glut in natural gas right now, and it provides about 30% of our power. So, those Tesla owners are (on average) powering 30% of their car on natural gas (made in the USA), and the rest on coal, nuclear, or the others I mentioned above (all made in the USA). So, you go ahead and keep financing terrorists and the countries that support them by propping up oil prices. And you can also keep threatening our national security by keeping us reliant on other countries for our energy. I will get an electric car. And I will be confident in my ability to use it regardless of who we go to war with because it uses the most flexible fuel source... all of them.

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