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Audi Creates "Fuel of the Future" Using Just Carbon Dioxide and Water
EwanPalmer writes: German car manufacturer Audi says it has created the "fuel of the future" made solely from water, carbon dioxide and renewable sources. The synthetic "e-diesel" was made following a commissioning phase of just four months at a plant in Dresden, Germany. Germany's federal minister of education and research, Dr Johanna Wanka, said she has already used the fuel in her Audi A8, and the company hopes to produce at least 160 liters of the crystal clear fuel every day in the coming months. "This synthetic diesel, made using CO2, is a huge success for our sustainability research," Wanka said. "If we can make widespread use of CO2 as a raw material, we will make a crucial contribution to climate protection and the efficient use of resources, and put the fundamentals of the 'green economy' in place."
Air?
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.
"Maybe, maybe not"? Please, you know that the answer is "not even remotely close". Even when you start with petroleum as your feedstock and only waste 10-15% of the energy it contains in refining and distribution, you've still got the car only turning 20% of the energy therein into useful kinetic energy (25% in the case of diesels), versus an average of about 85% of the electricty into kinetic energy (minus about 8% transmission losses), plus automatically gaining hybrid-style regen. Even if the process was 100% efficient - which it won't be anywhere even close to that - just the difference in propulsion technolgies would put the EV at 4 times the efficiency. Based on related processes, I'd wager that this tech is probably along the order of 30% efficient, so you're looking at about 13 times more range per kWh on an EV than a ICE car fuelled by this fuel. Which means 1/13th as many square kilometers of wind turbines, 1/13th as many solar panel factories, 1/13th as many dammed rivers, etc. Yes, it really matters.
But come on, don't play dumb and pretend that you actually think that the efficiency of taking electricity, extracting gases from the air, converting them into a mixture of complex hydrocarbons, then burning them in an ICE and facing Carnot losses, is somehow "maybe, maybe not" more efficient than using the electricity directly.
It really, really isn't. Almost everyone on the planet would be driving an EV at today's energy densities if one factor was significantly improved, but that factor isn't energy density. It's cost per kilowatt hour.
A 250Wh/mi EV that can go 400 miles (8 hours driving without a stop at an average speed of 60mph) needs 100kWh. At a reasonably good but not spectacular 200Wh/kg, that's 500kg. Due to electric drivetrains' superior power density, switching a low power gasoline drivetrain to an equivalent electric one saves about 100kg. Switching a high power gasoline drivetrain to electric can save a couple hundred kilograms. So you're increasing the weight of a car by a few hundred kilograms. You really think your average consumer would give a rat's arse if their car is a couple hundred kilometers heavier if it lets them drive on fuel that costs a third as much?
Of course, these are only a couple of the issues (I'll ignore environmental ones for now because I know a lot of people here don't give a rat's arse about them). Added weight hurts handling on cornering. But EVs make better power to weight ratios easier, and especially improve performance on low end torque. They also give designers a lot more flexibility on placement of components, which can translates into things like more spacious interiors for a given vehicle footprint, and almost always means a lower CG. One has to charge, but one never has to go to a gas station, and most people would find plugging in in their garage much more convenient than a special trip to a gas station and standing outside in whatever weather. This leaves open the question of charge times, of course. But if you can drive hundreds of miles on a single charge and charge up on a fast charger during lunch and then take off again, it's pretty irrelevant. Gasoline cars need big tanks to minimize the inconvenience of having to stop for gasoline regularly in your daily life. Using fast chargers of course means having a fast charger infrastructure, but that's an eminently addressable chicken and egg problem. Modern li-ion batteries deal quite well with fast charges.
The short of it is, if today's batteries were cheap enough - no better density or anything else - electric cars would very quickly take over the market place. Other improvements in technology will improve the sales proposition, but they're not essential.
"...but Republicans plan to come back with a new plan, where they just slash the tires on all the ambulances."
According to Audi's press release, this fuel is "chemically identical" to petroleum based diesel. So that pretty much answers your questions 1, 2, 3, 4, 6, and 8.
I've noticed most criticisms of EV charging simply relate to a total lack of imagination about how to address engineering issues. For example I've seen people rant and rave and run all sorts of calculations about how it's impossible to run large amounts of power through a manageable cable for an electric car, and therefore fast chargers are a big scam... pure vitriol, and overlooking one tiny detail: ... nobody says that your cable has to be passively cooled.
All of those cable thickness guidelines for home wiring and the like are for passively cooled cables. You don't have to use a cable the thickness of your wrist to deliver a fast charge, you just have to wrap it in a cooling sheath. Some of the highest power chargers already do this. Problem solved really, really easily.
"...but Republicans plan to come back with a new plan, where they just slash the tires on all the ambulances."
The high temperatures and pressures in the combustion chamber cause the nitrogen and oxygen in the air to react with each other to form NOx.
Source: I'm a diesel emissions engineer.
One of our competitors trademarked the term "hypothesis". From now on, we will call them "boneheaded ideas".
Saying "Now design a battery that can pull a 440,000 pounds or 200,000 kilograms triple trailer configuration across hundreds of miles of highway. " is silly, that's like saying "Now design a gas tank that can pull a 440,000 pounds or 200,000 kilograms triple trailer configuration across hundreds of miles of highway. " Batteries don't haul loads, electric motors do. And electric motors have far more power per unit mass and per unit volume than gasoline. Here's a comparison between a gasoline car engine and an equivalent power electric motor.
The heaviest haul vehicles *do* use electric drive. The vast majority of trains today, for example, are electric drive, and increasingly large haul trucks are switching to electric drive. The electric drive however is generally driven by either diesel generators or direct grid power to save the cost of having to buy batteries. Due to the battery cost, the largest ones out there re things like BYD's 60 foot / 120 passenger jointed bus and several models of 15-30 tonne haul trucks. The economics just aren't there for road trains like you're talking about at this point. It's not a tech issue, it's a battery cost issue.
Supplying the power is easy. Just thinking about it from a practical standpoint. These are batteries that can fast charge in half an hour or so. Discharging is generally easier on batteries than charging. But let's just say half an hour discharge. Li-ions now get up to a couple kilowatts per kilogram, but are only a couple hundred Wh/kg at best in terms of energy density. A road train may require something like 1000hp. That's 750kW electric. Actually less because you get a smoother torque curve, but let's ignore that. That's about 375kg of good li-ion batteries to be able to provide the needed power. Let's double that for poorer batteries, and add a bunch more for inefficiencies... let's go full overkill and say we need 1000kg of batteries to provide the needed power. 1000kg of batteries would hold about 200kWh of electricity. That's only 80 miles of range. Which is way less than you'd practically need for a road train.
That is to say, even with the most pessimistic look at it, even a pathetically under-ranged road train would have way more power than needed to run its engine. The more batteries you add, the more power becomes available. Power density is essentially a non-issue when dealing with li-ions.
Aviation is the highest-hanging fruit, but it's still a fruit that is within reach, and the small-scale electric prop plane market has gone from almost nonexistent to rapidly growing in the past 5 years or so. And there's lots of transitional techs, such as driving the compressor with electricity, which allows you to get rid of the turbine and thus increasing engine power and efficiency while reducing part count and maintenance.
False. First off, only permanent magnet motors require rare earths. Most modern EVs, like Tesla's offerings, don't use permanent magnets. Secondly, lithium-ion batteries do not use rare earths; I don't know where you got this idea. Lastly, rare earths aren't actually rare. China dumped the market, pushing other producers out of business, and then suddenly started holding back production for domestic uses, creating a temporary glut, but it's already started resolving itself.
This is once again false but I've already lost enough interest in this conversation to have to dig up research papers for you, so I'm just going to tell you "Google It". There've been many studies
"...but Republicans plan to come back with a new plan, where they just slash the tires on all the ambulances."
Technically, Diesel is combustible, not flammable; gasoline is flammable.
YMMV