Comment by rglover | Hacker News Reader

Comment by rglover | Hacker News Reader

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> In the end anyone who has a cellphone supports climate change.

Correct. And to your point, China is building coal plants, not decomissioning them [0].

What people in the West fail to understand is that in order for society to improve (and currently, remain stable), you need cheap, reliable energy. Renewables—seemingly, the proposed alternatives (wind and solar)—are neither cheap nor reliable. They're also dependent on fossil fuels to be produced (and shipped, and cleaned, and de-iced, etc).

One of the best things you can get behind if you really want to see CO2 emissions drop—which, if you dig into the data, a lot of it is based on models, not observations (which are dramatically below the models) [1]—is to promote nuclear energy and domestic manufacturing.

The former is near carbon-free (in operation) and produces ample energy (and modern solutions are both safe and have limited/reusable waste). The latter promotes both national stability (people have jobs) and reduces unnecessary emissions in other countries and for transport of goods.

[0] https://www.canadianenergycentre.ca/commentary-china-is-buil...

[1] https://science.house.gov/imo/media/doc/Christy%20Testimony_...

> (and modern solutions are both safe and have limited/reusable waste).

can you point me to something trustworthy that proves this point? I am not too much into the topic of nuclear energy but the last time I spent a night or two reading up on it the waste part still felt like a huge drawback.

The most trustworthy research I've read [0]/watched [1] is by Gwyneth Cravens.

[0] https://www.amazon.com/Power-Save-World-Nuclear-Energy/dp/03...

[1] https://www.youtube.com/watch?v=9RKtIs10R6Q (hosted by the Long Now Foundation)

Though a bit thin on info, this page from the DoE is interesting (links to some more in-depth stuff that I haven't read yet): https://www.energy.gov/ne/articles/5-fast-facts-about-spent-....

China dropped from 80% coal in 2010 to 57.7% in 2019. China’s exponential increase in electricity production means they don’t have nearly as many old coal power plants, but looking at what their building today is very promising.

And?

Re: China, there's clearly not an effort to move away from coal if they're constructing new plants. The percentages may be less, but if the overarching thesis is to limit things that produce CO2 altogether, this statistic is irrelevant when contrasted with their actions.

The percentage might be lower but if the whole is expanding enough the lower percentage might be greater that the previous.

> And

Coal power plants age. As their power demand has skyrocketed there are currently few 40+ year old coal power stations to be decommissioned. Looking at say 2050 the existing stock will mostly be replaced by whatever ratio they built between 2010 and 2050.

https://en.wikipedia.org/wiki/Solar_power_by_country

Solar in China went from 78 GW in 2016 to 254 GW 2020. The US had 40 GW of solar in 2016 and 75 GW in 2020.

Replaced by other coal power stations, though, not alternative sources. So again, not an incorrect statistic, but irrelevant in the context of the goal of reducing emissions globally (and the associated moral arguments/intimidations). Or does China get a pass because they produce goods cheaply for Westerner's?

Your assuming they are suddenly going to massively ramp up construction of coal power plants in a few years based on what?

Flip it around, does the US get a pass because they had a lot of really old coal power plants? In the last decade the US built a lot of Natural Gas power plants which sure isn’t as bad as coal, but they are hardly green. We’re falling behind on solar adoption, and wind is only slightly ahead of the global average.

Massive infrastructure changes take decades and we have arguably stagnated.

Suddenly, no. But they're not signaling intent to stop building them, either. If they're actively building now and saying they're going to build more, the logical conclusion is that they're going to build more over time.

And you're misdirecting. The U.S. doesn't get a pass. We're arguably one of the biggest targets that everyone points their fingers at (and domestically, shames its own population for relying on those energy sources).

My entire point is that the very things being obsessed over (solar and wind) are simply not feasible at the scale and capacities required to sustain our current civilization. The alternative is either nuclear, or significant population reduction (read: death, or, the logical conclusion of large swaths of humans either being denied access to energy or being priced out).

Like I've said elsewhere in this thread, the problem is less of a moral one and more of a mathematical one. E.g., the best solar panels only have a 20-23% effectiveness rate (https://archive.ph/wip/Vh1Qj). That means they cannot pull in ~80% of the solar power available. Batteries to supplement this mean more not less fossil fuels for production and mining of rare earth metals (and let's not even get into the human rights issues at those mines). Wind mills can't be built with windmill energy (and only work when the wind blows which is too varied to call reliable). Plain and simple: these alternative energy sources are not capable of replacing our existing energy needs wholesale without introducing significant chaos and likely, death.

The efficiency of solar panels is practically irrelevant. For scale for ~20,000$ of land in Arizona (60 acres) is getting ~240,000 kw of energy in full sun. At 2c/kWh and 10% efficiency you pay for that land in ~42 hours of full sun. Land costs are rarely more than 0.1% of total costs.

Anyway, nobody is going to run a major grid on 100% solar power because hydro and wind are cheaper than batteries. But let’s think pessimistic worst case. You want 50% over supply of solar so you never have to worry about long term storage (as in 1/3 of all solar is wasted).

That’s 3c/kWh. Batteries aren’t 100% efficient and degrade with use so let’s say 55% of power is provided directly via solar (much higher demand in day) and 45% of power is provided from solar fed batteries. If 1 kWh from a battery adds 10c the equation it’s roughly 3c + 10c * 45% = 7.5c/kWh.

Which is very close to what base load coal costs except because we’re using batteries which also covers peaking power plants. Frankly coal is only surviving in China because of how long it’s talking to build cheaper alternatives.

That's wildly inefficient at scale (and that's if it can be done reliably). Check my numbers here—should be correct but I'd appreciate pushback—estimating 50% of annual U.S. usage in panels vs nuclear plants: https://imgur.com/a/zeHo21R.

Even if we want 50% of our power nationwide to come from solar power, based on your 60 acre model that's still 6,429 of these installations or 385,753 acres (and that's with a generous output estimate of 2.5kWh per panel, per day).

A single 582 megawatt nuclear plant can generate 13,968,000 kWh per day and each one takes up a mile (640 acres).

Not to mention, 60 acres of panels takes a ton of manpower to maintain and keep functional. People, trucks, maintenance equipment, etc.

Keep in mind, too, these numbers are before we introduce everyone driving electric cars (assuming that's an ideal).

First 385,753 acres is trivial in the US. The federal government for example manages 640,000,000 acres in the US, it’s a big freaking country. We where doing above ground nuclear testing because we just had that much unused space.

As to output per day real world capacity factors for grid solar vary by location but tend to ~30% here’s a 29.7%. https://en.wikipedia.org/wiki/Mount_Signal_Solar So if a 400W panel averages ~2.9kWh per day 2.5kWh is perfectly reasonable ballpark estimate. Panel density varies but over 2000 per acre isn’t unreasonable as they are tilted. Still let’s use 2,000 or account for access roads etc.

As to nuclear it’s capacity factor in the us ~90% because it doesn’t need to follow the grid. Unfortunately that drops if you want to increase the number of nuclear power plants. France leaned into nuclear, but even exporting a lot of subsidized nuclear still they had capacity factors of ~70%.

By comparison at 2.9kWh per day panel * 2000 * 640 = 3,712,000 kWh per day from solar. Sure it’s less dense but not enough to be particularly meaningful especially as you don’t need access to water. The real difference people care about is it’s vastly cheaper and can actually scale. Try and hit 100% with nuclear and your stuck with sub 50% capacity factors or your need a lot of grid storage both of which dramatically increases the price. To actually be competitive long term, nuclear needs about an 60-80% cost reduction which is frankly never going to happen.

As to EV’s you need more space to park them than to install solar panels to power them. You also need more batteries for EV themselves than you need to backup a solar powered electric grid.

> By comparison at 2.9kWh per day panel * 2000 * 640 = 3,712,000 kWh per day from solar.

How is being less efficient by ~10,000,000 kWh per day preferred? That's a significant difference in output. You seem fixated on price and are ignoring the reality that solar panels inconsistently generate that amount of energy whereas nuclear is more stable. If climate change is literally going to destroy the world, then cost should be of less concern than "can it give us the power we need while reducing emissions?"

> Try and hit 100% with nuclear and your stuck with sub 50% capacity factors or your need a lot of grid storage both of which dramatically increases the price.

Can you share what led you to this 50% capacity number?

First intermittency is just a cost of battery question, because cost of one type or another is the only meaningful metric. Hell if land use bothers you we can put panels on rooftops, parking lots, between highways etc. It’s wasteful but plenty of people are doing it.

Also, 13,968,000 kWh per day * 70% capacity factor = 9,777,600 kWh so solar only needs 3x to 4x the land. Except, nuclear reactors need land near large bodies of water making that land far more valuable. So because you can’t put a nuclear reactor on the ultra cheap land viable for solar panels Nuclear actually ends up with higher land costs.

It's not a matter of technical feasibility (i.e., you could do it, but is it the best. most stable way), it's what is the goal. All of those batteries require fossil fuels to be produced, as do the solar panels. Favoring the model where you have to produce more (meaning more fossil fuels) is the antithesis to the greater point.

The more efficient option—even if more expensive—should be preferred. You may end up getting similar results, but the overall impact of trying to make solar panels play catch-up is more destructive in the long run. And they don't even catch up. By your own math, even at 70% capacity a reactor is 3x as powerful.

And re: the water requirements, those would also be a factor in hydroelectric so it's a moot point (assuming you see hydroelectric as a supplemental form of power to solar).

I've yet to do research into inputs of manufacturing a plant vs solar/wind/etc. so can't give specifics but just in the abstract what you've described sounds more wasteful (and that's if it can be done—there is far less ambiguity with the nuclear option).

The only necessary CO2 release from batteries is based on the current state of our global economy. Reduction in the amount fossil fuels used in the grid and mining equipment directly reduces the use of fossil fuels manufacturing batteries and solar panels all the way down to zero.

As part of being massively more expensive, Nuclear actually involves significantly more indirect fossil fuel usage due to those costs. For example all a nuclear power plants requires onsite fossil fuel generators which need to be run regularly: http://aa-powersystems.com/wp-content/uploads/3061871_OE_Bro... Yet those generators are left off of assessments of CO2 releases associated with nuclear power plants. Similarly the centrifuges reacquired to manufacture nuclear fuel require vast amounts of electricity to manufacture and run. The nameplate generation from Nuclear further ignores those ongoing energy costs.

the _numbers_ say nuclear energy costs about $150/MWh and utility-scale solar costs $24/MWh. Moreover, nuclear costs are going up even in places where they can and will ignore planning commission things like the PRC and solar costs are going down.

Now address the reliability issue. Cost is only one factor.

solar + batteries is $40/mwh?

Go further. How many batteries would it take to supply stable energy for the entire/majority of U.S. grids (and how long will those panels/batteries last)? How much energy will be produced relative to the number of solar panels that need to be installed? Is land conservation taken out of the equation in favor of panel installation?

This line of questioning was my "mind blow." It turns out, there are technological solutions, but they don't scale to meet demand (and if/when they do, it's inconsistent). And to boot, they're an aesthetic nightmare.

Everything humans build is accused of being an "aesthetic nightmare". Houses, roads, farms, feed lots, cities, etc. This is not a good argument against building important infrastructure.

When you consider the number that are required to supply our entire grid reliably (if even possible), it is. The only way to do it and maintain capacity is to use renewables alongside things like nuclear (or stay with fossil fuels and adapt our living habits).

Don't forget about the turtles, too: https://thehill.com/changing-america/sustainability/environm...

It's not a question of morality, but of mathematics. Can we sustainably and consistently produce enough energy using those methods long-term?

If the answer is "no," fooling ourselves into believing it's "yes" for the sake of ego/emotional pacification is setting us up for failure. I do believe the answer may be yes eventually, but on the current doomer timeline (always shifting but afaik the current doomsday is in ~12 years), the answer will remain "no."

Edit: rough solar panel efficiency stats https://archive.ph/Vh1Qj

Last winter we didnt see the sun for 6 weeks, and didnt have enough wind to overcome the cost of keeping wind turbine blades de-iced.

Batteries simply are not an appropriate solution to the problem.

We would need to make massive investments in high voltage DC lines across the country, dumping tons of CO2 into steel and concrete for rare usage patterns.

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