I like to imagine CO2 in solid form (dry ice) to help visualize the scale of the problem.
1) Burning a gallon of gasoline releases almost 10 kgs of CO2 into the atmosphere. Let's say the average driving American consumes 1.5 gallons of gas a day. That's almost 15 kgs of matter to deal with every day. Imagine instead of it being released as gaseous CO2, it accumulated in your car's trunk as dry ice. After a few days, what would you do with it all? Maybe you'd throw it in your basement or your backyard. After a week or two, all free space in even a large home would be totally occupied with the waste. And this is only for personal travel done by individuals. All transportation (including the transportation of goods) is less than a 3rd of U.S. CO2 emissions. If dealing with the waste of driving on an individual level is so hard, how can we possibly hope to deal with all CO2 emissions?
2) You can also do the same thought experiment with total CO2 emissions per capita, which is currently about 15.25 metric tons per year per person in the U.S. That averages out to 41 kg of CO2 per day. How could you possibly find a way to deal with 41 kg of dry ice per day.
Right now, our solution is to happily dump it into the atmosphere, which conveniently carries the CO2 away from us without us needing to worry. There really isn't a solution to this problem. It's a tragedy of the commons.
I like the idea of stacking up a lot of 1 meter cubes of pure carbon (graphite, or diamond!) into nice shapes. Each cube is just over 2 metric tons (2266 kg) of carbon, or the equivalent of 8 metric tons of carbon dioxide. 20 cubic kilometers per year is enough to get us back to pre-industrial levels in no time, and build some interesting monuments while we're at it. A roughly 4-kilometer tall pyramid, anyone? Low low price of ~4 trillion dollars each.
Casually building pyramids out of the ~57 cubic kilometers of carbon blocks would be pretty neat. Three 4 kilometer tall square based pyramids would do it.
They would also be the largest structures ever built by humanity by an order of magnitude. If we did it in Australia, we could employ the entire country twice over, and they would be the 3 new tallest mountains in Down Under (by 1,772m).
Its a wonderful image, but how do you propose sequestering the carbon? Without a powerful source of truly carbon-neutral energy, the losses incurred would simply see more carbon released downstream as a result of whatever process you choose to create such artful carbon chunks.
I still really enjoy the mental image of a post-industrial society in a few thousand years sitting on a foundation of diamond bricks. :)
Well, that's kind of down stream of what I was talking about - I am assuming that we can get to $250 per ton of direct carbon capture and then use something like a solar CO2 reduction system with a metal catalyst to strip the O2 off. But it's "merely a matter of money" at that point.
There's almost certainly some coking issues to overcome, but hey, we're already hypothetically taking on the largest industrial project of all time, roughly equivalent to all the effort spent to extract fossil fuels ever.
One thing I find particularly concerning in these plans is how people want to use them. Lots of people inevitably suggest under these posts that we just use DAC as counterbalance instead of reducing emissions. This is very much impossible as optimistic reduction scenarios still need trillions annually from every country and a no-reduction scheme would lead to hundreds upon hundreds of trillions of global DAC funding, far more than the GDP of the Earth is right now. This is the scale of the megaproject we need to undertake.
The only way we can make these things viable is massive funding and incredible carbon emissions reduction. This is very literally the largest industrial project that ever has happened, a re-terraforming of our own planet. There is absolutely no way we are going to succeed without full effort from all countries.
Honestly I don't expect it to happen. It's depressing, but I just don't think humanity collectively can take action on a scale like this without direct personal incentives, and I don't think there are any. I think we're going to drown in our waste products like yeast in a fermentation tank due to the tragedy of the commons.
With a properly designed electricity grid with interconnects to other grids and using all those idle electric cars as batteries we surely can solve this problem. The wind is always blowing somewhere, the sun is always shining somewhere, and most electric vehicles are idle at night when the sun is not shining and they could be used to smooth out the peaks and troughs. Most private vehicles are idle for more than 90% of the time.
If those were all electric with, say 50 kWh batteries they would be able to deliver an instantaneous power of something like 58 TW if the connectors could take it. But even if we assume that they are connected to only 7 kW charging points they could deliver 2 TW instantaneously. They could keep this up for an hour at the cost of losing less than 20% of a full charge.
Average US electricity consumption is about 500 GW so vehicle to grid plus an upgraded and properly interconnected grid should be able to solve the problem of intermittent generation.
I hope I haven't made a mistake in the arithmetic!
Also, we have lots of energy storage options that produce minimal amounts of waste.
Flywheels, molten salt, iron air batteries, literally dozens of alternative systems exist that are all viable and variably scalable power grid stabilization systems that can work harmoniously with renewable generation to keep electricity available to the consumer at both the individual and commercial level.
It needs a lot of financial and engineering investment to make headway, and these decisions would have to come from government leadership as otherwise there are too many cats to corral to ever make is succeed.
Sure, but if you separate the carbon from the oxygen and return the oxygen to the atmosphere you reverse the process and you’re back to, simply, having to deal with roughly the same mass of fuel as you originally burned. Which is obviously a tractable problem since you burned it in the first place.
If we had a good way to make synthetic gasoline from energy + carbon, we could have a totally carbon neutral fuel cycle where we use nuclear power to extract carbon from the air and produce synthetic gasoline.
It's monstrously inefficient to use nuclear power to create hydrocarbon fuels, truck them to petrol stations, and then burn them.
"Modern gasoline engines have a maximum thermal efficiency of more than 50%,[1] but road legal cars are only about 20% to 35% when used to power a car. In other words, even when the engine is operating at its point of maximum thermal efficiency, of the total heat energy released by the gasoline consumed, about 65-80% of total power is emitted as heat without being turned into useful work, i.e. turning the crankshaft"
See https://en.wikipedia.org/wiki/Engine_efficiency#Gasoline_(pe...
And the heat engine efficiency limits are only one part of the problem. Extracting the CO2 from the atmosphere also costs a lot of energy.
It is more efficient and simpler to just use the existing electricity grid to charge electric vehicles.
Charging the battery itself alone might be efficient. Take your 90% efficiency as true, and assume electric motor efficiency as 90% too, now the net efficiency drops to 81%. To reach your home, there most likely at least one step-up transformer and 2 or more step-down transformers. Assuming all those transformers are super efficient with a efficiency of 90% too, then the efficiency now becomes 65.61% for two transformers scenarios, 59.049% for 3 transforms scenarios. Considering the cost of manufacturing the battery, the huge weigh of the battery(85kWh now weighs around 540kg), the overhead of the power grid as a result of staggeringly over provisioning needed: assuming charging a 85kWh battery from 0% to 100% in 1 hour, using 220V AC power, nominal current required is 85 * 1000(kW) / 220(V) = 386.36A. Assuming power factor 80%, then the required currency is 386.36/0.8=482.95A, how much is going to cost for that capacity? 1 hour might be too aggressive, let take a concession to 8 hours, then the currency required is 60.37A. Just take look at your home's fuse, how much is that rating? Let's take another concession to require only 50% charge, then the required currency is ~30.19A, which is still around 10 times normal off-peak usage or ~3 times peak hour usage. Are you seriously considering to increase the capacity of the whole power grid by 3 to 10 times just for charging the car at home to 50% juice in 8 hours?
You're making some low assumptions for efficiency there - 90% is an absolute low end efficiency for transformers under full and non-linear load. Transmission losses for the UK grid average 8% total - regardless of how many transformers are involved.
You also forgot to take into account that most cars don't drive 300+ miles every day. The average car drives (depending on country) maybe 7000 - 10,000 miles a year. That means it will either be fully charged rarely, or topped up a little bit every night. We don't have to have a grid which can charge every car in the country from empty every night, we just need a grid which can charge a small fraction them.
In fact, in the UK where the average car drives about 7000 miles a year, the overall average power requirement is something like 200 W. That's well within the capacity of our grid.
We will have to take care to limit the surge effect of every car being plugged in at 6pm - but that just means delaying the nightly top up of most cars until the early hours (or whenever electricity is available).
While not familar with how things are in the UK, I understand DNO, which is the layer of the distribution network. Which means the part from power-plant->substation->high voltage line to at least one other substation near a city, or so. That does not include middle voltage into the city, or further downstepping until it is fit for your wall socket or similar.
If it claims to, it is a political fiction like so many other. In reality transmission losses from the one virtual plant powering the grid to your wall socket range from about
50% to 60% depending on the grid and many other factors.
Seems you have more detailed info. I just checked full-load efficiencies of transformers and it turned out to vary from 95% to 98.5% and the comprehensive efficiency can actually drop below 90%. If we factor in the loss on wires, I guess my estimate of loss per transformer layer 10% should be pretty close to actual. So I'm not surprised to see a transmission loss of 50% to 60%.
10% loss was just meant for quick calc, and I did not even factor in the loss in power generation etc.
And the assumption was only 50% of the capacity, so that would drop to ~150 miles. Again, it's claimed value, how much you can actually get out of it really varies.
If you just want to get 30 miles per day, then you will need ~ 6A, which is within household circuit rating but will still double the load of the ordinary family peak.
Please don't simply use Watts to calculate AC load, it will not give you the real current demand.
Using 10% for a quick calc is fine, if you only use it once. But you then multiplied that error by 3. The resulting assumption - that the transmission losses with 3 transformers would be ~73% (0.9^3) is completely wrong, given that we know total grid transmission losses are in the order of <10%
Well, look at your calc again. Transmission loss per my calc is actually 1 - 0.9^3 = 27.1%. At grid level, high efficient part(mainly stable industry loads) will cover up low efficiency of household loads.
Then don't. Use it for producing hydrogen. Compress, liquify it, slush it. Use the surplus electricity by nuclear, fantastic fusion, whatever, to suck the carbon out of the air, and make zeolites out of it to mix it into agriculturally used grounds, cat litter, whatever.
But the details may differ. If you can generate the synthetic fuel near the energy source, let's say a wind, farm you can shift the cost of transportation from one medium to another. That opens up possibilities to optimize on a network scale. In Germany, there is a pipeline network to transport and store natural gas to many many places. That transport is happening without trucks or ships driving around, I assume there are some pumps involved. But you don't have to move overhead mass.
Depending on your definition of "good" we already have ways to make liquid fuel from CO2+energy [1]. It just that you lose something like 90% of the energy from power plant to motion. Electric cars are much more efficient.
Nice graphic, but the ideal scenario would be to find a method that strips the carbon out of the CO2. We're putting about 50 Billion tons of CO2 into the atmosphere every year.
However, the Atomic weight of carbon is 12 whereas the Atomic weight of Oxygen is 16, and there are 2 oxygen atoms in every CO2 molecule, so 1 ton of pure sequestered carbon is 12+16+16 = 44/12 = 3 & 2/3 tons of CO2 removed from the atmosphere.
2.27 tons of carbon compacted together makes an approximately 1 meter cube.
Of course, that would mean we would have to sequester ~6 billion cubic meters (13.6 billion tons or the equivalent of 4,079 hoover dams in size, probably enough to resurface every highway and road in America 2-3 inches deep) of pure carbon every year to reach carbon neutral, and then we would need to go beyond that to begin to reverse the effects.
It would literally be the largest human undertaking in the history of the planet.
"Burning a gallon of gasoline releases almost 10 kgs of CO2 into the atmosphere"
I am not sure I understand the math here. 1 gallon of gasoline weights about 5kg, so how is that 10 kg of CO2 are released? Looks like mass will not be conserved in such a process. Am I missing something?
I haven't checked the math, but carbon from the fuel binds with oxygen from the air. CO2 consists of one carbon atom (12g/mol), two oxygen atoms (16g/mol). So, most of the weight comes from the oxygen from the air, rather than the fuel itself.
It's not a tragedy of the commons but a tragedy of markets. Markets cannot factor in these externalities. It's a known fault with market systems. And carbon taxes simply won't work for many reasons (hence why oil companies are pro carbon tax).
What we need is carbon rationing. Everyone gets X amount of carbon and prices of things are both in dollars and carbon rations. The rich, who use most of the carbon will have to buy from the poor who use very little. These rations will become more expensive over time until people don't get anymore. So they will only be able to buy things that are carbon neutral/carbon free.
Well, even without a spurce, they did give one very compelling piece of evidence: oil companies support this idea. Given everything we know about them, this is already strong evidence that it will be ineffective at curtailing the oil trade, which means it will be ineffective at affecting CO2.
A recent video leak shows an oil company lobbiest saying thay they publicly support a carbon tax, because they know it won't pass because they privately tell politicians to not pass it.
1. Oil companies support carbon taxes because they know they are politically dead in the water.
2. Yellow vest movement shows that if you punish the vast population for problems elite created, you will get mass protests.
3. The tax will be miss priced because it will be set by policy. Likely won't be high enough to stop global warming.
While a carbon ration doesn't have these problems since we know what the carbon budget is. Once it's spent it's spent and provides the right incentive. Instead of punishing regular people with a tax, it rewards people who use less carbon by giving them an asset. Since the vast majority of people use very little carbon if you divide up the the carbon budget evenly, you suddenly have a method to lower inequality and provide the right incentives for industry to move to a zero carbon world because when the rations are expired, they won't be able to have a business.
Carbon taxes simply have too many flaws and bad incentives and don't address the underlying problem, that we have a limited resource (carbon budget).
>What we need is carbon rationing. Everyone gets X amount of carbon and prices of things are both in dollars and carbon rations. The rich, who use most of the carbon will have to buy from the poor who use very little. These rations will become more expensive over time until people don't get anymore. So they will only be able to buy things that are carbon neutral/carbon free.
When you talk about "carbon rations," are you referring just to fossil fuels and petroleum-based products? Or are you referring to everything that contains carbon?
Given that life here is just brimming with carbon (we are, after all, carbon-based life), does that "carbon ration" include food? Pets? Yeast?
I'm not being snarky here, but it's not clear to me what exactly you mean. If you'd expand on that, it would be much appreciated.
1) Burning a gallon of gasoline releases almost 10 kgs of CO2 into the atmosphere. Let's say the average driving American consumes 1.5 gallons of gas a day. That's almost 15 kgs of matter to deal with every day. Imagine instead of it being released as gaseous CO2, it accumulated in your car's trunk as dry ice. After a few days, what would you do with it all? Maybe you'd throw it in your basement or your backyard. After a week or two, all free space in even a large home would be totally occupied with the waste. And this is only for personal travel done by individuals. All transportation (including the transportation of goods) is less than a 3rd of U.S. CO2 emissions. If dealing with the waste of driving on an individual level is so hard, how can we possibly hope to deal with all CO2 emissions?
2) You can also do the same thought experiment with total CO2 emissions per capita, which is currently about 15.25 metric tons per year per person in the U.S. That averages out to 41 kg of CO2 per day. How could you possibly find a way to deal with 41 kg of dry ice per day.
Right now, our solution is to happily dump it into the atmosphere, which conveniently carries the CO2 away from us without us needing to worry. There really isn't a solution to this problem. It's a tragedy of the commons.