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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."
You're right that we don't have enough renewable energy yet to make this a useful technology. But hopefully that day is coming.
Re synthetic diesel, it's like I've always said: screw the "hydrogen economy", hydrogen is cryogenic, low-density, and difficult to work with. You'd be better off joining those hydrogens to some nice stable carbon atoms to create a storable, pumpable, relatively safe room-temperature liquid fuel.
Maybe, maybe not, but I guarantee you it has a higher energy density than batteries, which is super important for vehicle applications.
Not really. Plant metabolism is usually < 10% efficient at turning sunlight, CO2 and water into useful biomass. And the process for turning useful biomass into hydrocarbon fuels is < 100% efficient, so solar -> fuel is very low.
In their case, they're using intermittent power, from wind and solar, to do a modified Sabatier reaction and make methanol, which then goes into an integrated Fischer-Tropsch process to make longer-chain hydrocarbons.
The resulting solar -> fuel conversion efficiency is HIGHER than going through biomass production.
... by the Dew of Mountains the thoughts acquire speed, the hands acquire shakes, the shakes become a warning
Regardless of the efficiency of the process, overgeneration of renewable power is still a huge problem. Germany actually pays its neighbors to take it when the wind is blowing and the sun is shining as the price of electricity between utility companies goes negative.
There are a few things we currently do with excess power, the ideal option is to store it until we need it, such as with compressed air in salt caverns.
In many cases, they dump it as heat into rivers as the storage infrastructure simply doesn't exist. This new option seems to be a great way to sequester carbon and deal with excess power generated through renewables. It also reduces our dependency on oil without having to sell new vehicles to utilize it, which is a very good thing.