People are literally celebrating a net positive carbon activity like they’ve accomplished something.
They’ve also been releasing it back into the atmosphere for free since the end of the Carboniferous.
The world emissions per capita are presently around 5T per year, per capita. The world has 5 billion hectares (out of 13B total) of agricultural land in general, overall (and generally if land _could_ be used for agriculture it _is_ used for agriculture), so generally, there's not a tonne of space to do lots of carbon sequestering quickly with agriculture, especially as you'd need to move the carbon you've created somewhere else.
The moral is that if you can ever get sequestering carbon down such that you can sequester 1 tonne of carbon for 20MWh power, you're close to a major winner, at least in all the deserts where you clearly can't grow bamboo but can grow solar, because at that point your cost of operations is just cost of infra. That startup thinks it can get down to around 1MWh/tonne, which is comparatively awesome!
My conclusion (before getting to something super scientific) was that if you want to rely on trees and swamps for your carbon capture, you basically end up with massive geopolitical issues because you need to cover most of the world in trees and swamps, but most of the world's land is already used to grow food. Meanwhile, carbon capture can work in areas where land is not (as) valuable.
If they are able to get to $50/tonne, that implies 1MWh/tonne, so that's about 500 tonnes/year per hectare. That'd mean that if you covered arizona in solar panels, you'd be sequestering 1/5 of human carbon output. Whereas if you grew bamboo, you'd cover the contiguous US for the same output.
Do I believe them? No. But even 10x worse is cheap enough to change the world.
In the same way we celebrate EV and PV production, even though those may still be carbon-positive at the outset. Especially when they were still in prototyping.
https://www.reuters.com/business/autos-transportation/lifeti...
https://www.reuters.com/business/autos-transportation/when-d...
> Based on a series of assumptions, the data showed that a Tesla Model 3 in the United States, for example, would need to be driven for 13,500 miles (21,725 km) before it does less harm to the environment than a Toyota Corolla.
> The model was developed by the Argonne National Laboratory in Chicago and includes thousands of parameters from the type metals in an electric vehicle (EV) battery to the amount of aluminium or plastic in a car.
> Argonne's Greenhouse Gases, Regulated Emissions and Energy Use in Technologies (GREET) model is now being used with other tools to help shape policy at the U.S. Environmental Protection Agency (EPA) and the California Air Resources Board, the two main regulators of vehicle emissions in the United States.
> Jarod Cory Kelly, principal energy systems analyst at Argonne, said making EVs generates more carbon than combustion engine cars, mainly due to the extraction and processing of minerals in EV batteries and production of the power cells.
TLDR ~1-2 years of driving, more upfront carbon emissions in manufacturing EVs but lower lifetime emissions overall.
PV:
https://www.sciencedirect.com/science/article/abs/pii/S09218... ("Implications of Trends in Energy Return on Energy Invested (EROI) for Transitioning to Renewable Electricity")
> Recent papers argue that the energy return on energy invested (EROI) for renewable electricity technologies and systems may be so low that the transition from fossil fuelled to renewable electricity may displace investment in other important economic sectors. For the case of large-scale electricity supply, we draw upon insights from Net Energy Analysis and renewable energy engineering to examine critically some assumptions, data and arguments in these papers, focussing on regions in which wind and solar can provide the majority of electricity. We show that the above claim is based on outdated data on EROIs, on failing to consider the energy efficiency advantages of transitioning away from fuel combustion and on overestimates of storage requirements. EROIs of wind and solar photovoltaics, which can provide the vast majority of electricity and indeed of all energy in the future, are generally high (≥ 10) and increasing. The impact of storage on EROI depends on the quantities and types of storage adopted and their operational strategies. In the regions considered in this paper, the quantity of storage required to maintain generation reliability is relatively small.