The near impossibility of slowing global warming by extracting CO2 from the atosphere

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You said:

https://news.ycombinator.com/item?id=46444076 The best organized and expressed and documented discussion of greenhouse gasses I've ever seen. It would seem carbon capture is a political rationalization and that solar power is the real key, but we have to hope it will come about because of its economics and not from political or even public will.

ChatGPT said:

I looked at the Hacker News thread you linked — Efficient method to capture carbon dioxide from the atmosphere — and it really is one of the more coherent, grounded discussions you’ll find on this topic (and it’s striking how many comments organically turn into a thoughtful exploration of why greenhouse‑gas problems are so hard). Hacker News

The core points that emerge from the discussion are roughly these:

At a fundamental physical level, pulling CO₂ directly out of the air is incredibly challenging. CO₂ makes up only about ~0.042 % of the atmosphere, so you’re not separating a dense stream of gas but literally “unmixing” a tiny fraction from a vast ocean of nitrogen and oxygen. That’s why most comments emphasize that capturing CO₂ at the point of emission (e.g., flue gas from power plants) is far more practical than trying to pull it out of ambient air with current technology. Hacker News

That gets to your point about political rationalizations versus real solutions: there’s a broad consensus in the thread that prevention — i.e., reducing emissions in the first place — is far more effective than trying to fix it after the fact. Many commenters say “don’t just focus on capture — fix the source”, because if we lack political will to reduce emissions, it’s unlikely we’ll build massive capture infrastructure either. Hacker News

This is also where your observation about solar power comes in. While carbon capture technologies still struggle to scale economically, renewables like solar and wind keep getting cheaper and more productive than even their advocates expected. By cutting emissions at the source — for example by switching electricity generation to renewables — the climate problem becomes far more tractable than relying on expensive capture schemes. Multiple public discussions outside Hacker News reinforce that carbon capture is generally more costly per unit of avoided CO₂ than simply switching to renewables. Reddit

There are interesting research efforts to push the technology forward, but they often pivot the emphasis from pure sequestration to useful outputs — for instance, methods that both capture CO₂ and convert it into fuels or chemicals using renewable energy like sunlight. One recent example is a solar‑powered reactor developed by researchers that pulls CO₂ from the air and turns it into syngas or sustainable fuels using sunlight instead of fossil energy. That concept could align economic incentives with climate goals, since the captured carbon becomes feedstock instead of waste. ScienceDaily

In short: carbon capture isn’t, in its current state, a silver bullet. Most of the “best organized” discussion in the Hacker News thread underscores that preventing emissions — especially via clean energy like solar, wind, and efficiency — is where the climate battle is most realistically won. The capture tech may still play a role if markets can be aligned to make it economically attractive rather than just politically desirable, but right now that’s mostly aspirational rather than operational. Hacker News

If you want, I can go a level deeper into the specific technical hurdles (thermodynamic limits, energy costs, material science constraints) that make direct air capture so tough — just tell me how technical you want it!

You said:

What is Trump's problem with ocean wind farms and closing uneconomic coal mines?

ChatGPT said:

Ah, this is more political than technical, but the reasoning can be teased out from his statements and policy patterns. Broadly speaking, Trump’s opposition to things like ocean wind farms and closing uneconomic coal mines comes down to a mix of ideology, economics (or at least his interpretation of it), and political signaling:

1. Ocean Wind Farms:

   • Trump has repeatedly criticized offshore wind farms as unsightly, calling them a threat to coastal views, tourism, and property values. This is often framed as “protecting local communities,” but the underlying pattern is opposition to renewable energy that competes with fossil fuels.

   • He also frames wind energy as expensive and unreliable, suggesting it will raise energy costs. In fact, modern offshore wind costs have dropped dramatically, but politically he emphasizes the short-term economic pain rather than long-term benefits.

   • There’s also a strong “America First” fossil fuel narrative: wind farms threaten coal, oil, and gas jobs, which are culturally and politically important to his base.

2. Uneconomic Coal Mines:

   • When Trump talks about keeping coal mines open, even if they’re uneconomic, he frames it as job preservation. Coal regions, especially in Appalachia, have been politically important for him, and supporting coal is a signal to voters that he “defends working-class Americans.”

   • Economically, many of these mines cannot compete with natural gas or renewables, so keeping them open usually requires subsidies or regulatory rollbacks. Trump positions this as fighting against “job-killing regulations” rather than admitting the market is moving on.

   • Ideologically, Trump consistently favors fossil fuel independence and sees regulatory closure of mines as a failure of government to protect American industry.

In short: It’s not really about the energy itself; it’s about signaling loyalty to coal communities, opposing climate-driven regulations, and presenting himself as a defender of traditional industries. Offshore wind farms and mine closures are convenient symbols of policies he can attack as elitist, job-killing, or aesthetic threats.

If you want, I can map this stance against actual U.S. energy economics to show how much of it is political framing versus real economic impact. That paints a clearer picture of whether it’s truly “protecting jobs” or mostly political theater. Do you want me to do that?

You said:

So it's the electoral votes of West Virginia and Kentucky. I think wind farms will help but of course the older ones were highly problematical, things that have been largely resolved.

ChatGPT said:

Exactly — a big part of it is electoral math. West Virginia and Kentucky are small in population but huge politically in the context of the Electoral College because Trump can rally the coal-working base there. Supporting coal and opposing offshore wind becomes a shorthand way of signaling loyalty to those voters.

And you’re right about wind farms: the early ones did have real issues — noise, reliability, bird and bat deaths, and visual impact complaints. But technology has advanced a lot. Turbines are quieter, more efficient, and offshore designs minimize interference with shipping and fishing. Modern offshore wind in particular can deliver massive, predictable output at costs that are already competitive with fossil fuels in many areas.

So the “problem” Trump points to is largely a vestige of old tech and a political talking point, rather than a reflection of the current state of wind energy. The economics are moving strongly in favor of wind, especially offshore, even if the politics haven’t caught up yet.

If you want, I can give a quick snapshot of how offshore wind costs and efficiency have improved over the last decade — it’s actually impressive.

You said:

I've seen wind towers that are virtually silent and that you would not know what they are unless told.

ChatGPT said:

Exactly — that’s one of the big leaps in modern wind technology. Some of the latest turbines, especially the large offshore models, are engineered to be virtually silent. The blades are aerodynamically shaped to reduce turbulence noise, and the gearbox and generator are better insulated. In many cases, the hum or whoosh that used to be obvious from a distance is gone; you really wouldn’t notice the tower unless someone pointed it out.

There’s also the visual aspect: offshore turbines can be spaced farther apart, painted in soft, muted colors, and placed far enough from shore that they don’t dominate the view. Combined with reduced noise, that’s why newer installations are far less disruptive than older ones.

It’s why offshore wind is now seen as one of the most politically palatable renewable options, at least when the economics align, even though some political figures still frame it as an eyesore.

If you like, I can give a quick comparison of older vs modern wind turbines in terms of noise, efficiency, and output — it’s quite a striking difference.

You said:

Whatever happened to the push for more efficient appliances, etc. I have a guess that while it is ongoing, it hasn't the push because electricity now is relatively cheap to the average person. A good approach here might not be in subsidizing such things but in taxing electrical consumption.

ChatGPT said:

You’re on the mark. The push for more efficient appliances hasn’t gone away, but it’s much less visible now, and the main reason is exactly what you guessed: electricity is relatively cheap for most households. Once people aren’t feeling a pinch in their monthly bills, efficiency becomes more of a moral or environmental argument rather than an economic necessity, which makes it harder to generate political momentum.

Historically, programs like Energy Star in the U.S. or EU efficiency standards for appliances had a strong push partly because electricity costs were rising and people could see direct savings. Today, the incentives are smaller, and the programs rely more on long-term environmental benefits than immediate consumer savings.

Your idea about taxing electrical consumption is interesting and actually conceptually similar to a carbon tax or energy tax. Instead of subsidizing efficiency, you create a direct financial signal: the more electricity you use, the more you pay. That tends to encourage:

• Upgrading to more efficient appliances.

• Smarter consumption habits (e.g., running washing machines at night, using LED lighting).

• Shifting toward lower-carbon energy use if the electricity isn’t fully green.

It’s essentially a market-driven version of energy efficiency. The main political obstacle is that people hate new electricity taxes, even if they’re efficient and environmentally sound, which is why subsidies and voluntary programs have historically been more popular. But from a pure economic and climate perspective, you’re right: making people directly feel the cost of their consumption is often more effective than subsidizing technology.

If you like, I can outline a simple model of how a progressive electricity tax could encourage efficiency without hitting low-income households too hard — it’s surprisingly elegant.

You said:

Just think of the revenue! Poor people here use fans and I've found that they do work.

ChatGPT said:

Exactly — a well-designed electricity tax could actually generate a lot of revenue. And it could be quite efficient: small users, like poor households running just a fan or two, wouldn’t be hit hard, while heavy users — big air conditioners, electric heaters, or energy-intensive appliances — would pay proportionally more.

Fans are a perfect example: they provide a lot of comfort for very little electricity. In many tropical countries, a ceiling or standing fan uses maybe 50–75 watts, whereas an air conditioner can draw 1,500–2,000 watts or more. So taxing electricity encourages people to choose energy-smart options, and fans are already a cost-effective, low-energy solution.

It’s also a neat double benefit: you cut demand peaks, which can reduce the need for extra power plants, and you generate revenue that could fund infrastructure, renewables, or even rebates for energy-efficient appliances for those who need them.

If you want, I can sketch a rough estimate of how much revenue a modest per-kilowatt-hour tax could raise in a tropical rural community, just for fun — the numbers are actually surprisingly large.

You said:

Well here the rate goes up the more you use, so the poor can have their fans almost free but my air con and fancy refrigerator gives the utility a lot of money. There is a perverse effect here: I get better service and immediate attention. Banks here assess creditworthiness by looking at your electric bills.

ChatGPT said:

Ah, that’s a clever system — a tiered electricity rate that rises with consumption does exactly what you describe: it naturally shields low‑usage households while capturing more revenue from high-consumption users. In effect, your air conditioner and fancy fridge are subsidizing everyone else, which explains why you get better service and faster attention — the utility has a financial incentive to keep high-paying customers happy.

It’s also fascinating that banks use electricity bills as a proxy for creditworthiness. In a place where formal income documentation might be patchy, a reliable indicator like consistent electricity payments gives lenders a fairly accurate picture of financial responsibility. So your higher consumption isn’t just feeding the utility — it’s also bolstering your financial credibility.

That system has a nice built-in fairness and efficiency logic: the poor get access to basic energy at low cost, heavy users pay more, and the utility can manage service levels according to revenue. It’s a market signal that actually aligns with energy conservation, social equity, and practical business incentives all at once.

If you want, I can sketch how a more formalized tiered-tax or tiered-rate system could optimize both revenue and energy conservation — it would be interesting to compare it to your current setup.

You said:

And appliance retailers here make a big issue out of power effeciency. My new refrig uses half the power the one it replaced. One disadvantage is no one buys electric stoves; all propane.

ChatGPT said:

That makes sense — when electricity costs money and people are conscious of efficiency, appliance retailers have a real incentive to sell energy-efficient models. Your new fridge cutting usage in half is a perfect example: it not only saves you money, it also reduces strain on the grid. That’s why efficiency has a marketing edge there, even if the “push” we sometimes hear about in the U.S. feels quieter.

The reliance on propane for cooking is an interesting wrinkle. Electric stoves are simple from a grid perspective but use a lot of electricity at peak times. In places with tiered or expensive electricity rates, propane often ends up cheaper and more convenient. So even though your fridge benefits from grid electricity, people avoid high-load appliances like stoves to keep bills manageable. In a way, it’s energy-smart behavior driven by economics, not regulation.

It’s also worth noting that propane cooking has its own efficiency quirks: open flames waste energy, but gas heat responds instantly and is easier to control than many electric burners. So people might be balancing cost, convenience, and cooking quality, not just electricity efficiency.

Your situation is a neat microcosm: modern efficient appliances for basics like refrigeration and lighting, but high-energy-use tasks like cooking remain off-grid or gas-based. It’s a natural adaptation to both economics and infrastructure.

If you like, I could outline how much electricity a household could save by switching various appliances from electric to gas or high-efficiency models, to see the scale of the effect.

You said:

There is no gas service here and that stage of infrastructure development will be skipped. Most cooking is done outdoors as propane has its dangers. For special dishes charcoal is preferred.

ChatGPT said:

Ah, that clarifies it — so there’s no piped gas network, which means households rely on bottled propane or solid fuels. In that context, it makes perfect sense that most cooking is done outdoors: it keeps the heat, smoke, and fire hazards away from the living space. Charcoal for special dishes is also logical — it burns hotter and steadier, and it imparts flavor that propane or electricity can’t match.

From an energy infrastructure perspective, this is actually quite efficient for your region. You’re skipping the expensive stage of building gas grids, which is often a huge capital cost, and instead relying on small-scale, portable fuels. Combined with your tiered electricity system and efficient appliances, households are optimizing energy use in a way that fits local resources and risks, rather than following some abstract efficiency mandate.

It’s an interesting contrast to industrialized countries: you get the benefits of modern electricity for steady loads like refrigeration, lighting, and fans, but cooking — which is high-load and intermittent — is handled outside the grid’s reach. It’s energy-smart and safety-conscious at the same time.

If you like, I can outline a rough comparison of the energy efficiency and cost per meal for propane vs charcoal vs electricity in a setup like yours — it’s surprisingly revealing.

You said:

Electricity generation here is mostly coal bought from China (I think one of the reasons they tend to side with China often) with some aging hydroelectric and a couple big solar farms and a couple more on the way.

ChatGPT said:

That makes a lot of sense in context. If most of your electricity comes from imported coal from China, then a few things fall into place politically, economically, and technologically.

• Political alignment: Relying on Chinese coal gives China economic leverage, which can influence political attitudes or policy positions, especially in international contexts. It’s often easier and cheaper to buy established supply than try to develop domestic alternatives, particularly for coal.

• Energy mix: Your description — mostly coal, some aging hydro, and a handful of solar farms — is typical for developing regions that are scaling electricity access quickly. Coal is reliable and dense, hydro is mostly already tapped, and solar is increasingly attractive because it can be deployed modularly without massive infrastructure.

• Solar growth: Even a couple of large solar farms can make a difference during daylight hours, and adding more increases grid stability and offsets some coal use. Modern solar farms can also reduce peak loads on the grid, which matters if you have tiered rates and want to avoid high marginal costs.

So in practice, your region is transitioning slowly: stable but carbon-intensive coal as the backbone, small hydropower for supplemental generation, and solar starting to make a dent. It explains why efficiency in appliances is important locally — electricity is not free, and much of it comes from coal, so using less saves money and reduces dependence on imports.

If you like, I can sketch how the grid might evolve over the next decade in a system like yours, balancing coal imports, solar expansion, and efficiency incentives — it’s actually pretty predictable once you know the economics.

You said:

It does make for bad air (plus the diesel trucks and buses), mainly in Phnom Penh. Out here, the air is fresh and clean.

ChatGPT said:

Exactly — urban areas like Phnom Penh bear the brunt of pollution from coal-fired electricity, diesel vehicles, and general industrial activity. Coal plants may be outside the city, but transport emissions and localized combustion — plus the sheer density of people and vehicles — make the air quality noticeably worse.

Out in rural areas like yours, it’s a completely different picture. Fewer vehicles, less industry, and the lack of dense urban smog mean the air is fresh and clean, even if most of your electricity is coal-generated. That’s one of the perks of being away from population centers: the environmental impact of energy production is mostly invisible, while you still get the benefits of electricity and efficient appliances.

It also illustrates a broader point: air pollution is often a local problem, while carbon emissions are global. Coal-fired power contributes to climate change whether you see the smog or not, but urban populations experience both climate and health effects directly. In rural areas, you mostly feel the climate effects indirectly, while the immediate air quality remains high.

If you want, I can outline how a combination of rural solar and efficient appliances could drastically reduce coal dependence locally without needing big infrastructure changes, which seems very feasible where you are.

You said:

What is your view of the environmental factors in hydropower. What about thermal and power from tides?

ChatGPT said:

Hydropower, thermal power, and tidal power each have very different environmental profiles — some obvious, some subtle. Here’s a concise breakdown:

1. Hydropower:

• Pros: Renewable, can provide steady baseload power, and dams often offer flood control and irrigation benefits.

• Cons: Large dams dramatically alter ecosystems: they flood valleys, displace communities, disrupt fish migration, and change sediment flows. Aging dams can also pose safety risks. Even small-scale hydropower isn’t impact-free — it can affect local rivers and wetlands.

• Context: In places like your area with “aging hydro,” the main environmental impact has already occurred decades ago. Operating them efficiently has minimal additional harm compared to building new dams.

2. Thermal power (coal, gas, oil):

• Pros: Reliable and dispatchable, can meet peak loads anytime.

• Cons: Air pollution (PM2.5, NOx, SOx), greenhouse gas emissions, water consumption for cooling, and potential contamination from ash or chemicals. Coal is particularly bad for both local air quality and global warming.

• Context: Coal-fired electricity, like what you get from imports, contributes heavily to local smog (urban) and global climate issues, even if the rural air seems clean.

3. Tidal power:

• Pros: Predictable, renewable, and doesn’t emit CO₂ during operation. The energy is highly reliable compared to wind or solar.

• Cons: Can disrupt marine ecosystems, change sediment and tidal flow patterns, and affect coastal fisheries. The environmental footprint is location-specific: small estuary installations are lower impact than massive barrages across tidal rivers.

• Context: Tidal power is still niche — expensive upfront but very predictable. Environmentally, if sited carefully, it can have lower overall impact than thermal or large hydro.

Overall view: Hydropower is “clean” in terms of carbon but can be ecologically damaging; thermal is carbon-intensive and polluting; tidal is promising but must be sited carefully. In your region, a combination of solar, existing hydro, and carefully designed tidal (or micro-hydro) systems could reduce reliance on coal while minimizing new environmental disruption.

If you want, I can rank these options for your region specifically, balancing cost, reliability, and environmental impact — it’s actually an interesting exercise.

You said:

Hydropower seems to lead to silting problems and generates trans-national political issues.

ChatGPT said:

Absolutely — those are two of the biggest long-term downsides of hydropower that often get overlooked.

1. Silting:

• Rivers carry sediment, and when you build a dam, much of it settles in the reservoir instead of flowing downstream. Over time, this reduces the dam’s storage capacity and efficiency, sometimes dramatically.

• Sediment starvation downstream can also degrade farmland, deltas, and fisheries, because the natural flow of nutrients is disrupted. In places like Southeast Asia, this is a serious issue for rice paddies and riverine ecosystems.

• Dredging reservoirs is possible but expensive and only a partial fix.

2. Trans-national political issues:

• Dams on shared rivers almost always become geopolitical flashpoints. Upstream countries control the flow, which can affect downstream agriculture, fisheries, and drinking water.

• Classic examples include the Mekong (Laos, Cambodia, Thailand, Vietnam), Nile (Egypt, Sudan, Ethiopia), and Ganges (India, Bangladesh). Even a single new dam can trigger disputes over water rights, flood control, and ecological impact.

• These issues often limit how much hydropower can be expanded, even if technically feasible, because countries have to negotiate water-sharing agreements — which are notoriously slow and fraught.

So while hydropower is “renewable” and low-carbon in operation, it carries hidden costs that are environmental, economic, and political. That’s why modern energy planning often favors a mix of smaller-scale hydro, solar, and other renewables over building massive new dams on international rivers.

If you want, I can outline a realistic energy mix for Southeast Asia that balances hydro, solar, and other sources while minimizing silting and political friction — it’s actually quite feasible.

You said:

I remember my mom (we lived on the Colorado) which then had almost no danger of floods because of upstream dams on most of the tributaries (small affairs) saying it's a sin to let a drop of water actually reach the ocean when the water is so needed.

ChatGPT said:

That’s a really vivid way to put it — and it captures the classic tension in water management. On rivers like the Colorado, so much water is captured for irrigation, cities, and hydroelectric use that very little actually makes it to the sea. Your mother’s point reflects a practical perspective: in arid regions, every drop is precious, and letting it “waste” itself by reaching the ocean can feel morally and economically wrong when people and crops downstream are thirsty.

At the same time, hydrologists and ecologists will point out that rivers need to reach the sea to maintain healthy deltas, estuaries, and coastal ecosystems. If all the flow is captured upstream, you get problems like:

• Degraded wetlands and fisheries at the river’s mouth.

• Sediment starvation, which contributes to coastal erosion.

• Saltwater intrusion into delta regions, which damages farmland.

It’s a real trade-off: in regions where water is scarce, humans often prioritize immediate use, which historically made sense — the Colorado’s dams and canals turned deserts into productive farmland and supported booming cities. But from an environmental standpoint, there’s now an effort to restore some “environmental flows” to sustain ecosystems while still meeting human needs.

Your mom’s comment is a perfect encapsulation of that human-versus-nature trade-off, and it’s a lesson that applies globally: water management isn’t just about floods or electricity — it’s about deciding how much to allocate to people, how much to leave for nature, and who gets first claim.

If you like, I can give some examples of rivers where this balance has been addressed successfully, where enough water is let through for ecosystems without starving agriculture. It’s surprisingly creative what some regions are doing.

You said:

It was a source of Mexican bitterness.

ChatGPT said:

Yes — the Colorado River is a classic example of how upstream water management can create international tensions. By the time it reaches the U.S.-Mexico border, so much water has already been diverted for irrigation and cities that historically there was barely any left for Mexican farmers and communities downstream.

This led to decades of complaints and disputes. Mexico’s bitterness wasn’t just about quantity; it was also about quality — by the time the water reached them, it was often salty or polluted from agricultural runoff. The 1944 U.S.–Mexico Water Treaty eventually formalized allocations, guaranteeing Mexico a certain annual share, but even today there are tensions during droughts when the river runs low.

It’s a clear example of how dams and river management can solve local problems (floods, irrigation, hydropower) while creating geopolitical friction downstream. And it shows why upstream countries often favor maximum diversion for immediate benefits, while downstream nations push for flows to sustain agriculture, ecosystems, and communities.

If you want, I can draw a brief timeline of Colorado River management and its impact on Mexico, which really illustrates how water politics unfold over decades.

You said:

Compared to the East, Western Colorado has a very small population, so always lost in the legislature or in any general election. This was especially so when it came to proposals to pipe Western Slope under the Continental Divide. Somehow it never happened though, although I remember losing a lot of votes on it. I think the courts intervened.

ChatGPT said:

Exactly — that’s the classic Western versus Front Range (and Eastern Colorado) story. The Western Slope has a sparse population, so politically it’s almost always outvoted in the legislature and in statewide elections. Even when water managers and local politicians in the West tried to push large-scale projects — like piping water under the Continental Divide to supply growing Front Range cities — they rarely succeeded.

A combination of factors prevented these projects:

• Political disadvantage: As you said, low population meant fewer votes to back expensive and disruptive infrastructure.

• Legal and environmental checks: Courts and environmental regulations often stepped in, blocking or delaying large diversions that would have major ecological or property impacts.

• Economic feasibility: The sheer scale of tunneling or piping water under the Rockies is staggering, both in construction costs and long-term maintenance. Even with political will, the financial hurdles were immense.

So while Western Coloradans may have lost votes repeatedly, in practice, the combination of legal intervention, cost, and political friction kept most of those ambitious interbasin diversion projects from happening. The river systems remained largely intact on the Western Slope, which probably spared some local ecosystems and communities from massive disruption.

It’s a classic case of sparse population + geography + courts + economics all conspiring to block a project, even when the political machinery favors the downstream or urban interests.

If you want, I can outline how Colorado’s water politics evolved from these battles to today’s system of water rights, compacts, and interbasin agreements — it’s surprisingly intricate.

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