15

Simply put biochar is charcoal made by burning biomass and using it to enhance soil and/or capture CO2. The idea is that the charcoal improves the soil's carbon content and functions as a carbon sink for atmospheric CO2. This would be especially useful for depleted soils. The idea of using charcoil to enhance to soil was derived from the Terra Preta found in ...


8

Ecologists refer to this as 'gross productivity' and define it to be dry weight plant matter per area per year. In temperate climates this is likely to be a grass. Switchgrass has been proposed as a bio feedstock, both because it's highly productive, and the plant pulls most of the necessary trace nutrients back into the roots in fall. Poplar and willow ...


8

A ton of coal is roughly 240 kWh of electricity. At present, the coal mine north of me charges the local power company something like $1.90 /ton for coal. So the fuel cost is about a cent per kWh. The wholesale price of electricty is about $.03/kWh. The retail price of that power is $.15/kWh. A $24/ton carbon tax would be 10 cents/kWH. That's enough to ...


5

I think you're up against two three at least four separate problems: The scale: rallying 1M people to plant 16k trees apiece over 20 years is no way a "guerrilla" operation; it's a mass movement. It won't be covert: everyone will know about it, and landowners will probably object more or less strenuously. The distribution: if you have anywhere near 1M ...


5

One way to look at it to compare like with like is to look at the photosynthetic efficiency since carbon is fixed through photosynthesis. By this measure, sugar cane comes on top, converting about 8% of the incomming sunlight energy into stored carbon energy.


4

No, and no. Current production costs of biochar are in the hundreds of dollars per tonne. (It shouldn't be that expensive.) By comparison the mining costs for coal at my neighbor, the coal mine, run about 90 cents (canadian) per ton. It will be a while. General paper about biochar with nominal $200/ton wholesale price from a unit that processes 2000 ...


4

As soon as you plant a forest it starts to decay. Initially the growth rate is faster than the decay rate. At some point it reaches equilibrium. To maximize carbon capture you want to plant something that adds biomass quickly. To keep it sequestered, you need long life. Your best strategy is to plant fast growth trees for your area, coupled with shade ...


4

The short answer is no, not anywhere close to 200ppm and not appreciably lower than ambient conditions. The modern standard for buildings is a full air change every three hours. This means your houseplants would need to achieve your target level on a full house volume of air every three hours. There is no practical arrangement which will achieve this. ...


4

The answer is: Unknown. So try it. We need more data points. In general if energy can be extracted from a reaction, some bacteria does it for a living. Given the nature of certain ecozones, notably various pines that have a strong firesuccession (Lodgepole, Jackpine) then a series of low temmperature burns should leave substantial carbon in the soil. ...


3

Both of the links you shared are important videos to watch for anyone interested in learning about the process and should be considered required viewing material in classrooms where agriculture is taught. The process works well and can be applied to other kinds of livestock as well. The "chicken tractor" is a popular method that employs similar techniques ...


3

Air travel sustainability problems, even if you limit the category to climate change impacts, are not limited to greenhouse gas emissions. Atmospheric transport of emissions is difficult and, since jet fuel isn't a pure (or even homogeneous) substance, it's not always possible to know what is coming out of the aircraft in what concentrations. Biofuels were ...


3

I found this article regarding lawns. It suggests that lawns could be regarded as carbon sinks only if they are not (frequently) mowered, and do not use pesticedes. Also: An acre of established temperate forest can hold from 2,000 lbs. up to 6,000 or more lbs. of carbon per year, depending on the age of the trees and other conditions. Mature ...


3

For all-electric passenger jets, battery capacity must increase to hold four times more energy per unit mass Currently available batteries have poor specific energy compared to jet fuel: Jet fuel: 11.9 kWh/kg Diesel: 13.3 Gasoline: 12.9 Lithium metal batteries (e.g. LiPo): ...


3

Another option that could be explored (and indeed is, to a limited extent) is the increased use of airships. Being neutrally buoyant, they need much less energy per trip, and the propulsion could be provided by solar power (they also have a large area on top of the envelope to hold solar cells). The downside, of course, is the need for large amounts of ...


3

An unexploited forest has many benefits but carbon sequestration is not an exclusive driver. You can invert the logic and argue that any wood used for making durable things is an additional carbon storage opportunity. To capture carbon, plant growth must be sustained while preventing burning or decay in the open. Once the growth/decay equilibrium is ...


3

Gail Taylor's team at the University of Southampton is looking at almost exactly this question. Their primary focus is on fastest-growing bioenery crops, but the answer is going to be pretty much the same as for your question, as carbon sequestration is roughly the same as bioenergy accumulation. They are concetrating on three species currently: poplar, ...


3

Since grass and switchgrass already been mentioned; Hemp and Paulownia tree may be the alternative answer. They are among the fastest growing plants. For hemp, one unit land area of hemp(s) can produces as much cellulose as 4 unit land area of trees.


2

I'm going to focus on the potential for enhanced oil recovery, permanent sequestration and government support for active projects. Carbon capture technology is a whole other beast. Projects Currently Underway sequestration.mit.edu has a great database of active and cancelled CCS projects in the US. I was surprised how many projects are on the burner now. ...


2

If you are going to use wood gas to run a generator, don't bother removing the CO. Burn it. https://www.youtube.com/watch?v=X3KipK49v7g is a vid on making a woodgas powered truck. That said: Consider getting a manual transfer switch, and a gas or diesel powered generator. While the power may have been off for 10 days this time, I found in our (shorter) ...


2

This master's thesis by Dahiru Rufai Ahmed at the university of Oulu provides a comprehensive background into the removal of CO2 from wood gas. On pages 36-37 it mentions the water-gas shift (WGS) reaction as a method of adjusting the hydrogen/carbon monoxide mixture or removing CO entirely to get pure H2. "The WGS reaction is an exothermic reaction (∆Hr ...


1

Cattle have become unpopular because they have been accused of farting methane. This is the main answer to your question. However in ecologically sound pastures cattle do restore CO2 to the soil, and they probably fart much less. If their "emissions" have been measured on cattle fed on a single species of newly sown grass, or on silage, they would not be the ...


1

Trees follow the logistics curve for growth. More complicated, the number of trees descreases as they get larger. E.g. after a forest fire, lodgepole pine sprout at about 10 per square foot. In 10 years there is about 1 per square yard. At 30 years it's one per 6 foot square. The fastest mass growth rate is when a given area is mostly at the 1" diameter ...


1

There are many problems with the article you cited, but I agree with the main point it makes about the need for extensive research before any global scale solution should be attempted. Nevertheless, extensive field trials are not required to definitively prove the effectiveness of biochar to sequester carbon. Simply dig a hole in poor soil one foot wide and ...


1

There is certainly one way how to do carbon sequestration with biochar: fill empty coal open pit mines with that charcoal, and cover with soil. That's how the fossil fuel in that pit was stored for a very long time before humans thought it's a good idea to dig it up and burn it. When wanting to give biochar simultaneously tasks for soil amendment, it ...


1

I believe its all about mass, biomass is effectively sequestered CO2. In year one a lawn probably has a greater mass than a one year old tree, and so more CO2 sequestered. But in year twenty the tree has a greater mass about 1 tonne which is 3 tonnes of CO2, and the lawn, if its been regularly mowed still only has the same biomass as it did in year one. Of ...


1

Two things you need to consider: Storing more CO2 in the soil means you want to have more life in there. This points to the avoidance of fertilizer and pesticides in your lawn. Peat has a huge capacity to store CO2, so you may consider turning your lawn into wetland if possible ;)


1

Carbon capture (CC) to offset or create synthetic fuels seems poised to replace fossil fuels that are otherwise difficult to replace. In the plans I've read in the last few months, that seems to be the general idea for air travel. CC from the air is being developed. E.g. Climeworks (Zurich, Switzerland), Carbon Engineering (BC, Canada). Extracting it from ...


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