[HN Gopher] Using solar farms to generate fresh desert soil crust
___________________________________________________________________
Using solar farms to generate fresh desert soil crust
Author : PaulHoule
Score : 113 points
Date : 2023-04-22 15:44 UTC (7 hours ago)
(HTM) web link (phys.org)
(TXT) w3m dump (phys.org)
| twobitshifter wrote:
| I thought this was going to be about using solar energy to
| 'terraform' the area around solar farms in deserts. (Terraform
| isn't the right word on earth but you get the idea) Is anyone
| exploring that?
| wolfram74 wrote:
| I think maybe an appropriate term would be anthroform? I feel
| an argument can be made that whatever form the earth is in,
| it's terraformed almost by tautology, but the kind of planetary
| gardening projects we must engage in to keep it in a good shape
| for /humans/ is to give the earth a particular form for us.
| actionfromafar wrote:
| I thought it was sort of that.
| sfink wrote:
| Sort of the opposite, in fact! It is _blocking_ solar energy to
| 'terraform' the area around solar farms. (Well, first it
| terraforms the area under the solar farm, then we use that to
| terraform the surrounding area.)
|
| We are creating a shaded microclimate underneath a field of
| solar panels, which apparently can be harvested to meaningfully
| impact a larger area with a different climate.
|
| I wish they'd given figures on the expansion factor: one
| hectare of solar farm is enough to seed X hectares of desert.
|
| It reminds me of how the Amazon rainforest is fed in great part
| by a single small area in the Sahara (the Bodele Depression in
| Chad). The area is 150km x 500km, but it seems like the
| relevant area (the winds have to exceed 36km/h to pick up
| enough dust to matter) may be smaller?
| credit_guy wrote:
| > could empower a small-scale enterprise to rejuvenate all idle
| agricultural lands within the county, spanning more than 70,000
| hectares, in under five years.
|
| Just for a sense of scale, the US has 158 million hectares of
| arable land (and arable land is just a subset of agricultural
| land) [1].
|
| [1] https://worldpopulationreview.com/country-rankings/arable-
| la...
| civilized wrote:
| I'm not sure how we compare these numbers? The 70,000 is just
| for one county. So, scaled up across the country, it would be a
| lot more. Or was that your point?
| credit_guy wrote:
| To be honest, I wasn't trying to push any point, although in
| hind sight it appears I was. The idea that the soil below the
| solar panels can thrive sounds great, it looks like an
| absolute win-win: you get both cheap electricity and better
| soil.
|
| But articles are trying to always show big numbers, and
| without context it is hard to know what these numbers mean.
| 70k hectares is not that much. A better way to play the area
| angle is, in my opinion, this: if we properly electrify the
| US, we can stop making bio-ethanol. The US is using 12
| million hectares of arable land for that; that can be put to
| better use.
| upsidesinclude wrote:
| And it's such a shit product...
|
| Subsidy to set food production at odds with energy is a
| colossal error
| Reason077 wrote:
| It would be if there was a shortage of food, but that
| isn't really the case in the USA.
|
| Besides, I'd imagine that the corn used for ethanol
| production could easily be turned in to food should that
| need ever arise.
| TulliusCicero wrote:
| > 70k hectares is not that much.
|
| Yes, but they were only looking at biocrust potential from
| the three largest solar farms in that particular county.
|
| Obviously if you wanted to help soil nationwide you'd also
| need to target solar farms nationwide. Plus, in the future
| we can expect more solar farms than we have currently, it's
| only quite recently that solar has started to become a non-
| trivial amount of energy generation in the US, as you can
| see in this chart: https://en.wikipedia.org/wiki/File:USA_e
| lectricity_productio...
| llsf wrote:
| With cheap and abundant energy we can do lots of interesting
| things.
| jay-anderson wrote:
| This is very neat. I've heard of similar benefits to combining
| solar panels and agriculture.
|
| I'm glad this is getting some attention. I live in the desert and
| often I hear from people who don't live here the sentiment that
| it's useless, dead land, but the opposite is true. The deserts in
| the southwest US are alive with all sorts of interesting and
| beautiful plants and animals.
| briantakita wrote:
| Just make sure the solar panel components contain no heavy
| metals or other toxic substances. Same with the batteries.
| These materials do leach & contaminate the ecosystem & water
| table.
|
| Bonus points if no children were compelled to mine or
| manufacture the material.
| renewiltord wrote:
| Comment made me curious so I looked it up.
|
| They do contain heavy metals and toxic substances. As do the
| batteries.
|
| Looking it up, it appears that the contamination occurs
| during disposal so it's not a good idea to dispose of these
| in the kind of landfill where they can get into the water
| table, and it's preferable to recycle them.
|
| It appears that mining these materials in formalized
| industrial mines has no child labour according to Human
| Rights Watch. It's artisanal independent mines that are risky
| from this perspective.
|
| Overall, the technology seems safe.
| jeffbee wrote:
| Mass-produced PV panels contain hardly any heavy metal.
| Some of them contain lead in the solder but this is
| avoidable. Most of the noise is about cadmium, but you will
| note that CdTe thin film panels enjoyed brief market
| success before being stomped again by the irresistible
| decline of the price of Plain Old Silicon. Even CdTe panels
| are basically inert, coming from the factory as a stable,
| insoluble glass. If you read the research papers about the
| possibility of cadmium pollution in soil from CdTe panels,
| their methodology is to grind the panel into a fine powder
| and scatter that on the ground. Why would anyone do that?
| Look at the funding for the papers. The "research" was
| designed as anti-renewable propaganda.
| upsidesinclude wrote:
| > in soil from CdTe panels, their methodology is to grind
| the panel into a fine powder and scatter that on the
| ground.
|
| Sounds a bit off, but consider the effect of having the
| glass thrown into a landfill where it will be bulldozed,
| day after day, for several years. It is just jumping to
| the end of what would be the eventual outcome after a few
| decades of disposal.
|
| I don't find that to be an arguable study design.
|
| "Anti-renewable propoganda" is certainly a thing, but
| it's also true that many champions of renewables keep
| their blinders on when it comes to making assessments.
|
| Solar and nuclear are the demonstrably effective means of
| producing large scale power, but they don't provide
| portable energy density (the kind we demand). Battery
| technology has finally come into the realm of
| competition, but that has been with extensive and
| persistent research for decades.
| jeffbee wrote:
| If chucking PV panels into landfills were actually a
| widespread practice, I am sure you could produce some
| statistics about how much of that has actually occurred.
|
| The fact is that PV panel economic lifetime is way, way
| longer than reactionary renewable opponents want you to
| believe. It is not 15 years, or 25 years, it is more like
| 100-400 years. Nobody needs to decommission them en
| masse, yet. And even if they suddenly did, it still does
| not present a disposal issue. Suppose there are 100
| million PV panels in California. This is the right order
| of magnitude for our peak generating capacity. If you
| took every PV assembly in the entire state, stacked them
| 50 deep so they were about as high as a man, and just put
| them in a field, they would not even cover 500 acres.
| That's less than a square mile. Total non-issue.
| xbar wrote:
| I would amend your conclusion to say "Overall, the
| technology seems to be safely manageable."
|
| Let to rot after funding is depleted is a recipe for
| disaster. Consider the original decommissioning plan for
| San Onofre nuclear power plant:
| https://sanonofresafety.org/nuclear-waste/
| ClumsyPilot wrote:
| That kind of true for every human activity. Anything is
| dangerous if incompetent / malevolent actors are in
| charge.
|
| Even pig farms cause runoff of manure and fertiliser into
| rivers, where they cause Eutrophication - massive algae
| blooms that consume all oxygen in the water, killing all
| the local fish and fauna and producing massive swaths of
| hte ocean where the only living thing is Jellyfish.
| PaulHoule wrote:
| Almost any area builds soil structure if you leave it
| undisturbed. It's important to remember that solar
| installations aren't an industrial concrete slab but leave
| space for secondary agricultural use. I have a hayfield which
| produces better year over years because the roots of the grass
| are undisturbed.
| MichaelZuo wrote:
| I've heard India has had some successes combining solar and
| rural farms/deserts. Though I'm not sure how exactly.
| upsidesinclude wrote:
| This sounds great and seems like a 'no brainer' if you grew up in
| the desert.
|
| I wonder why these studies don't focus more attention on current
| infrastructure though.
|
| Urban buildings have equally massive footprints and are already
| on the grid.
|
| The entire urban highway system of blacktop is tied to the grid
| and acts as a thermal mass, increasing ground temperatures and
| contributing to the heat island effect. Why not cover it?
___________________________________________________________________
(page generated 2023-04-22 23:00 UTC)