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Reading things like that really makes me think that we'll literally do _anything_ rather than tackle the root cause.

Soon enough people will work on de orbiting earth further away from the sun rather than stopping living unsustainable

I fully support tackling the root causes. That said I can not do that by myself and my experience interacting with governments has unfortunately made me a bit cynical.

What I as an individual can most certainly do is install a modular home under ground if a company were inclined to make one, preferably out of recycled material. I could rent an excavator tomorrow as they are closed on Sunday.

I have a theory that if enough homes were underground that would substantially reduce the load on the power grid from a lack of HVAC use, freeing more capacity for EV vehicles and buying more time for power companies to upgrade the power grid and reducing overall carbon emissions world wide. Perhaps power companies could lobby governments to make under ground homes affordable, modular, carbon neutral and most importantly safe. The wealthier and more influential people could even have underground garages to protect their expensive toys from the environment and theft.

Living underground tackles the one issue that no green revolution is going to fix - space. Above ground space is fixed and the population will continue to rise. We can build upwards or downwards but upwards blocks light, which is also a fixed quantity.

living space isn’t remotely a concern, if we all (the whole world) lived in a single mega-city as dense as NYC it would be about the size of Texas

light also isn’t much of an issue, we could power the world with a solar array the size of New Mexico

fertile farm land, stable temperature, and distribution are much much much larger issues

living underground might be good for reducing electricity needs for heating and cooling, or avoiding certain natural disasters… but probably isn’t very useful for much else

Most of the US is solving this by building sideways (i.e. sprawl). It’s far cheaper than digging down, at least in the short term.

If space above ground is fixed, space below ground is also fixed. Seems like a tautology to me.

If anything there’s probably less useable space under the (land) surface than above it.

> but upwards blocks light

Also known as "shade," which is a nice thing to have when temperatures are rising.

Also the buildings themselves still get the light and can funnel it into living/working spaces or just turn it into electricity. Sure it’s shadier at ground level in a tall dense city but like, I’m pretty sure it’s more feasible to build km-ish tall buildings that still manage to post some light down to street level than it’ll ever be to build living space that goes equivalently deep.

thing is the root cause is a coordination problem, it's impossible to get 8 billion people to tackle any issue unilaterally, so we are left with solutions that allow individuals to opt in to a future where survival is not dependent on everyone else

Agreed if you mean WE as a hypothetical union of all individual humans and human institutions. But all of this makes a lot more sense to me if you distinguish between individuals and institutions. Institutions (companies / governments / Unions / HOAs / PTAs w/e) seem like they're impossible for any individual to control except by collective action which is just more institutionalization thats impossible for individuals to control. Individuals can make decisions to do things like install solar panels on their house, invest in a heat pump, buy an electric car, live in walkable areas, plant a garden, NOT work for or purchase things from institutions they disagree with, build an underground house etc within the confines of what institutions will allow. I don't think theres any more that we can do, the rest seems like subjugating guilt narrative bs and self-satisfied collective action virtue posturing.

There is no WE imho, its individual human beings against global industrial institutions. Collective action just propagates more destructive / uncontrollable institutional behavior. Federated / decentralized individual action propagated through federated / decentralized communication networks.

Anyway I can barely remember to brush my teeth or buy groceries so what do I know.

I kind of agree, but on the other hand we are so far along that we won’t be able to stop climate change but merely restrict it. So apart from restricting it we also need to adapt.

Underground construction is really hard to do correctly. Partial earth bermed foundations as you mentioned are a good compromise, especially if the earth is built up. But even then, drainage and soil pressure are big engineering concerns.

Also you have no control over how much thermal interface you have. My office is on the first floor on a slab. It's great in the summer and freezing in the winter, despite a carpet.

Digging down becomes increasingly expensive vs equivalent volume building up.

Why not just use ground source heat pumps? It's much easier to bury some tubes than habitable spaces. It's easier to move heat/cold where you need it. You aren't forced into a fixed thermal flux.

Underground construction is really hard to do correctly.

I agree it is harder to do correctly and costs more. It's an investment that if done right could outlast any above ground home. But that is quite a loaded caveat on my part, done right. That's why I envision this being done in a factory and very specific instructions and compliance requirements that if adhered to should produce more predictable results. The bunkers I see people building today are all custom one-off designs and I think that is where they get into trouble.

I do like the idea of heat pumps. That would be a balanced trade-off for those that do not want to mess with putting in a home under ground.

>It's an investment that if done right could outlast any above ground home.

I would think this was true, but what I've learned so far suggests it's not...

Underground, you're not finding refuge from harmful forces on your structure; they exists there too. Things shift, things crack, things leak, humidity causes problems, the whole exterior now endures a chemical interface with the surroundings (and all your Vault-Tec steel will corrode at some speed determined by the nature of the local media).

If you're lucky enough to have near-surface bedrock where you are, digging into that is probably your best bet, but, even then, it seems like an uphill battle.

I'm really not sold on the costs of digging down being all that high, long-term.

I'm 100% sold on it being expensive today, but I can come up with ways to drive them /way/ down with automation. The critical thing is:

1) You don't need materials.

2) You don't need to transport anything other than a digger

I agree it's hard, like engineering a CPU was hard, but I think Elon's got the right idea with the Boring Company. It's not /fundamentally/ expensive. Fundamentally, building in-place with available materials should, some day, be cheap.

> 1) You don't need materials.

In this context, you do. You need material structural stability (which is nontrivial, even for partially bermed structures; digging down further is a different story too) and for human habitation. Even above-ground you see retaining walls everywhere in places like New England because dirt likes to move. Worse, you'll need relatively expensive materials, and ones that are OK with contact with a lot of moisture. Maybe plastics can be the answer to some degree, if ones that are structurally sound and not tasty to microorganisms can be employed en masse, but the default answer is probably steel, and that won't last forever (or even all that long).

Beyond that? People aren't generally high on dirt walls and floors. And smoothing stone to presentation levels in-place, ensuring regularity, etc. is not a trivial task.

It could be done, don't get me wrong. But we have wear and decay problems above the surface that probably pale in comparison.

I feel like the materials are whatever is found on site.

That may mean that a machine may need to be able to sort, smelt, sinter, form, ram, engrave, or otherwise process whatever it found on-site.

That's definitely non-trivial, but in the sense of making a CPU with millions of transistors, and not in the sense of Mt. Rushmore. The R&D costs will be astronomical, but there isn't much there which is /fundamentally/ expensive, at least so long as you're not going to deep.

I can describe a number of beachheads and early markets -- places where you don't need all of that at one, or ultralow costs. I think the Boring Company has a decent one.

And that’s without even mentioning light.

Sure, sunlight can be piped down underground for natural lighting, but I’d really miss being able to see trees and blue sky from my office desk.

In the summer you'll want the surrounding ground to take away the heat, but in the winter that will be too cold, so you'll need to heat your home. There will be some (well quite a lot actually, as you don't have any insulation if you want ground cooling in the summer) waste heat transfering into the surrounding earth. Over time that will heat it up, so in the summer it'll be less effective at cooling.

This is actually why the London Underground is so hot in the summer. It wasn't always like this, but over time the ground surrounding the tunnels has heated up.

https://citymonitor.ai/transport/londons-tube-has-been-runni...

Well, when you reach the ~23c sweetspot, can't you just stop heating in the winter?

Underground houses are really cool, but we can get the same effect by building above ground with thicker walls. No AC needed when building with adobe.

Partially earth beamed falls under passive solar design. That's actually got real potential for helping us meaningfully mitigate these issues.

Time to start a radon mitigation company!

I suspect that if a subterranea home were built so poorly that radon gas is infiltrating the walls then so would water. Both would have to be factored into the design. Modern bunkers are designed to keep radon gas out and are equipped with high flow ventilation systems. High pressure shotcrete or some similar material should more than suffice to keep gasses and water out.

Radon is a problem in traditional brick and mortar basements as those walls are typically just one layer of brick and mortar. Water and radon can easily penetrate through micro-cracks that develop over the years in traditional basements.

"I suspect that if a subterranea home were built so poorly that radon gas is infiltrating the walls then so would water."

I'm no expert, but your statement makes me ask... Why then do we have homes with basements that have radon problems, but not water problems? I don't think the two problems are always related.

Water infiltration depends on the amount of water and type of soil and the drainage designed into the basement. e.g. layers of concrete and rows of shale/rocks for drainage. Not all basements are equal. The amount of radon depends on the quantity of uranium and thorium in the soil/dirt. So you are right they are not always related but the mitigating controls can be potentially related. Some construction companies just focus on maximizing profits in my opinion and some individual home builders will use construction dirt that contains low or no uranium or thorium.

> Underground homes would also be tornado resistant

earthquakes are another problem though

True, though it appears to be the same liquefaction risk that above homes are subject to. [1] Geological surveys would be more important and I suspect compensatory insurance would be harder to acquire. That said if the automation brought the cost of these units down far enough then perhaps only liability insurance would be required as the unit could potentially be recycled if it were designed with that in mind. One could rent an excavator at $150 to $400/hr depending on size required to remove the top soil. If the rooms were modular then the excavator could lift or maybe even drag out the damaged room to be swapped out. If not modular then a crane would be required.

There are bomb shelter companies designing underground facilities that can withstand earth movement and allow the occupants to escape harm. I won't link to those companies as I feel they are over-priced and this could be done much more efficiently with advancements in automation and recycled materials. For small facilities like homes I believe this is a mostly solved problem.

A harder problem in my opinion would be a commercial mine due to the size/scale. Steel I-Beams and steel plates throughout a lengthy/deep mine would be very expensive as opposed to the wire mesh and 8' anchor bolts and shotcrete used today. A modular home would be far less likely to cross liquefaction and plate fault boundaries.

[1] - https://www.sciencedirect.com/science/article/pii/S246796741...