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The effect of the UBI is to change the ratio of buying power between the poorest and the middle class

Essentially eroding the middle class more than has already happened. Good plan!

The flaw in this thinking is that wealth is not zero sum. If this were to happen, it would only indicate a (continuing) failure of policy to grow wealth. It would have been best to address this first, and (temporarily) eroding the middle class may be the cost they pay for this failure. Helping the poorest among us, can help us all; ditch the divisive mentality and cooperate to raise the floor of prosperity, instead of cannibalizing your fellow humans. If you don't, you will eventually share their fate.

The first step to effective UBI rests on understanding that energy is the fundamental source of wealth. Energy once provided by slaves to allow a few to prosper, and most recently provided by fossil fuels, allowing many to prosper. As supplies dwindle, the result is obvious. To prosper, we need access to affordable and abundant energy.

Now we face a fork in the road: one path leading to a post-scarcity future of universal prosperity based on nuclear energy, or the other: a "green" mirage, which will lead civilization to ruin, devastating the natural world in the process, despite the best of intentions. Reality will not bend to wishful thinking; please spend time to learn about the issue.

I see no one is taking global warming seriously... Yet.

I will believe that global warming is a serious problem when people start talking about building nuclear power plants again.

I hear them scream from rooftops on how we must have an "all the above" energy policy. Then when nuclear power comes up then it's everything except that. Okay then. If nuclear power is somehow a greater hazard to the world than nuclear power then I'll just wait until someone takes this problem seriously. Either global warming is in fact a real threat and we get nuclear power later, potentially after it's too late to stop it's worst effects, or global warming turns out to be a nothingburger and we all go on happily burning oil and coal.

I can wait. Until then I'll leave some reading material.
http://cmo-ripu.blogspot.com/2...
http://www.roadmaptonowhere.co...
https://www.withouthotair.com/

This spraying water in the air is a nice plan but the guy proposing it even explains that we will still need a plan to stop burning coal. I've not seen any working plans yet that do not include nuclear power. Some people claim future technology will save us but that's not a plan, that's wishful thinking. That's waiting at the port for a ship that might never come.

Here's a couple more.

https://www.withouthotair.com/

http://www.roadmaptonowhere.co...

They use the numbers given by the wind and solar advocates. The wind and solar industries are using numbers that don't add up to sell themselves. It only takes a bit of math to see this. It's science. If you deny the science, from the wind and solar industries themselves, then I'd like to see your "science" explain a future without nuclear power and without poverty.

Whatever, another article about how we are all doomed.

Here's what I want to see, solutions that work. Wind and solar don't work because without massive levels of storage to even out the varying load to the varying demand then it simply cannot keep the lights on. Also, add up all the resources needed to build all these windmills, solar panels, and batteries, and you will find yourself a situation that will destroy the economy and/or the environment in trying to dig up all the materials needed.

You think wind and solar don't have any environmental impact? Where do you think all that steel, aluminum, copper, concrete, rare earth elements, and so on come from? We dig it out of the ground, that's where it comes from. Same for the batteries, that stuff has to be dug up, refined, machined, molded, and transported to the construction site. This takes energy and materials. Energy and materials we cannot produce in any meaningful time frame.

We need solutions, not another restatement of the problem. Seems no one wants to speak of what that solution might be.

Oh, and I give citations on why the solutions brought up so often will not work.
http://www.roadmaptonowhere.co...
http://cmo-ripu.blogspot.com/2...
https://www.withouthotair.com/

No. It's people making a risk assessment that is meaningful to them. The math works a little bit like this: "if I am personally involved in a nuclear disaster, it might cause me to rapidly fall apart from the inside out, with blood coming out of every orifice, while another type of power is either totally safe to be near (PV, or wind so long as you aren't literally under the turbine) or will kill me suddenly." It doesn't matter how large the chance of a disaster is, so long as it's nonzero and there's precedent for it happening.

Yeah and that's people getting it way wrong. The absolute worst accident was Chernobyl and reactors with a void coefficient like that have never, ever been legal outside of the Soviet Union.

Those accidents have simply never happened in anywhere else.

But the particulates from coal can and do cause lung cancer and heart attacks, which much more follow the mould of you falling apart from the inside out. Lung cancer is barely detectable until it's far gone and a non fatal heart attack can leave you barely mobile. But people just sort of cope with the idea of coal even though we all agree it's a good idea to phase it out.

To reiterate: coal has cause far more nasty deaths than nuclear even including Chernobyl and yet it receives a small fraction of the concern.

...? You're the one expressing concern! Why can't you even tell me what level causes you concern?

Yes, nearby. So what? Basically every coastal region is suitable for some type of wind power. For those few which aren't, you ship in power on - get this - WIRES.

You're oscillating between high level details, low level details and pedantry without coherence. Let me repeat:

The UK does not have enough renewable resources to meet its energy needs. Here's my citation (an entire website and book on that precise topic):

https://www.withouthotair.com/

If you disagree, provide some kind of counter argument.

Most people will mostly follow the law. If you set laws to encourage same, then yes. But really, I expect humanity to fail here.

Same. I think we're as likely to set the right laws as we are to adopt nuclear power in a sensible manner.

The only people who didn't shit up their home bigly were the "natives" (actually the second wave of migrants) of the North American continent. They had over 10,000 years of relative peace and stewardship before white people showed up to cut everything down and turn it into luxury hotels

Not entirely. I know the natives around New Mexico (Bandelier National Monument) developed some spectacularly destructive farming techniques given their tech level and died out/abandoned the area well before the Spanish turned up. They did leave behing some cool rock houses though.

Why don't you google it?

I believe I explained this to you before. I know what I know because I "googled it". I shared what I know with you and where I got it from so we can both know of what we are talking about. If you don't share your sources then I cannot know what you know except what little bit you've shared. If you know of a reputable source on all of this then point it out to me so I can soak it in, not just the tiny bits you put in a few words on a web forum. By not sharing your source I have no idea on if what you know is current, has any backing in reality, or if you just pulled it out of your ass. I did "google it" and what I found out was shown in the sibling post on algae derived fuels being a worthless technology. As that is what I read from Google therefore I concluded that you are full of shit and have been either lying to me or been seriously mislead by your lesser skills with Google.

Energy per gallon: 370kWh ... so you need to produce 390e6 * 379kWh in electricity per day and convert it loss free into synthetic fuel. That means 6158750000 kW power capacity. That is 6159 GW. With a capacity of roughly 0.5GW per reactor, you need 12,000 new reactors. Good luck finding places for only a fraction of them in the US. But I guess I made somewhere a mistake, so feel free to divide it by a factor of 10 :P

Also shown in the sibling post is that nuclear power takes 1/10th the area of solar power. Solar power including bio-conversion by algae, PV collectors, solar thermal arrays, or whatever. As shown on the Without Hot Air website ( https://www.withouthotair.com/... ) the amount of solar power one can achieve varies greatly by location. Even in an ideal location nuclear power can produce four times the energy by area compared to solar, assuming 100% conversion into something useful. With 250 W/m^2 of average solar power in Hawaii that limited amount of land available on the island would be better used for nuclear power, again assuming 100% conversion of solar power to something useful. The 250 W/m^2 is the power of the sun on the ground, converting that to something useful with the technology we have today means we'd get more like 25 W/m^2. (That math shown in detail here: https://www.withouthotair.com/... ) The 1000 W/m^2 of a nuclear power plant is the electrical output, which assumes the heat left over is just vented to the air. If that heat is instead used in a fuel production process the conversion to useful energy might be improved, or not. We do know that if we use that land for electrical production we will get far more electricity from nuclear power than any solar collectors could. With all else equal, such as that electricity used to drive the same fuel synthesis process, then nuclear power wins by an order of magnitude.

So, where are we going to find places to put all those nuclear power plants? That's easy, push over all those stupid solar collectors and put a nuclear power plant there. Without Hot Air claims a nuclear power plant producing one gigawatt takes less than one square kilometer of area, so 6000 gigawatts would be about the size of the state of Delaware. That's far less area than the size of Arizona as computed in the sibling post for the needed area for solar power to produce the same output.

If you want me to believe algae has any possibility of producing enough fuel to meet any nation's transportation needs, and do so at a price competitive with synthetic fuels from nuclear power, then give me some links on sources which show their math. I "googled it" and found out you are full of shit. If you want me to believe otherwise then you are going to have to be VERY specific on where you got your information.

Why don't you google it?

I believe I explained this to you before. I know what I know because I "googled it". I shared what I know with you and where I got it from so we can both know of what we are talking about. If you don't share your sources then I cannot know what you know except what little bit you've shared. If you know of a reputable source on all of this then point it out to me so I can soak it in, not just the tiny bits you put in a few words on a web forum. By not sharing your source I have no idea on if what you know is current, has any backing in reality, or if you just pulled it out of your ass. I did "google it" and what I found out was shown in the sibling post on algae derived fuels being a worthless technology. As that is what I read from Google therefore I concluded that you are full of shit and have been either lying to me or been seriously mislead by your lesser skills with Google.

Energy per gallon: 370kWh ... so you need to produce 390e6 * 379kWh in electricity per day and convert it loss free into synthetic fuel. That means 6158750000 kW power capacity. That is 6159 GW. With a capacity of roughly 0.5GW per reactor, you need 12,000 new reactors. Good luck finding places for only a fraction of them in the US. But I guess I made somewhere a mistake, so feel free to divide it by a factor of 10 :P

Also shown in the sibling post is that nuclear power takes 1/10th the area of solar power. Solar power including bio-conversion by algae, PV collectors, solar thermal arrays, or whatever. As shown on the Without Hot Air website ( https://www.withouthotair.com/... ) the amount of solar power one can achieve varies greatly by location. Even in an ideal location nuclear power can produce four times the energy by area compared to solar, assuming 100% conversion into something useful. With 250 W/m^2 of average solar power in Hawaii that limited amount of land available on the island would be better used for nuclear power, again assuming 100% conversion of solar power to something useful. The 250 W/m^2 is the power of the sun on the ground, converting that to something useful with the technology we have today means we'd get more like 25 W/m^2. (That math shown in detail here: https://www.withouthotair.com/... ) The 1000 W/m^2 of a nuclear power plant is the electrical output, which assumes the heat left over is just vented to the air. If that heat is instead used in a fuel production process the conversion to useful energy might be improved, or not. We do know that if we use that land for electrical production we will get far more electricity from nuclear power than any solar collectors could. With all else equal, such as that electricity used to drive the same fuel synthesis process, then nuclear power wins by an order of magnitude.

So, where are we going to find places to put all those nuclear power plants? That's easy, push over all those stupid solar collectors and put a nuclear power plant there. Without Hot Air claims a nuclear power plant producing one gigawatt takes less than one square kilometer of area, so 6000 gigawatts would be about the size of the state of Delaware. That's far less area than the size of Arizona as computed in the sibling post for the needed area for solar power to produce the same output.

If you want me to believe algae has any possibility of producing enough fuel to meet any nation's transportation needs, and do so at a price competitive with synthetic fuels from nuclear power, then give me some links on sources which show their math. I "googled it" and found out you are full of shit. If you want me to believe otherwise then you are going to have to be VERY specific on where you got your information.

It most likely will be bio gas and/or oils made from algae.

No, it won't. I've seen the math and bio-fuels simply cannot provide the energy we need for transportation. Citation:
https://www.withouthotair.com/... (You'll have to read through the next few pages to get it all, not just the page I provided a link to.)

Everything in your post is a steaming pile of unsubstantiated bullshit. There is no energy future for the world that does not include nuclear power or widespread poverty. Oil prices will rise as it runs out, at some point this price point will reach to where synthesis of fuel from nuclear power is profitable. Or, more likely, the price of synthesized fuel lowers to the point it be competitive with petroleum drilled from the ground. Whatever the case the lines will meet on that graph and we will slowly transition from petroleum to synthetic fuels. I simply prefer it happen sooner than later. You spreading your lies is not helping.

For someone that constantly tells people to "Google it" for themselves you seem quite ignorant on the subject. Go Google it. If you can't be bothered to watch the videos given to you as links in a post then don't reply as if you have something useful to say.

Why do we need nuclear? What is wrong with existing renewable and storage technology?

The problem is we can't build it fast enough. Wind, solar, hydro, and geothermal take too much material. We don't have enough capacity to create sufficient amounts of steel, concrete, and other materials to build enough renewable energy to displace coal.

Here's an article that gives just a taste of the problem:
http://cmo-ripu.blogspot.com/2...

A very comprehensive analysis was done here:
http://www.roadmaptonowhere.co...

And here:
https://www.withouthotair.com/

If you want to tell me that we can wait until we have the infrastructure to build enough cement kilns and steel mills to keep up with the closing of current coal and nuclear, as well as increased needs for these materials not just for energy generation but also other construction, then I have to wonder just how urgent this need is to hold off global warming.

Even with over-building capacity it's still much cheaper than nuclear, and one of the primary objections to doing anything about climate change is the cost.

Nuclear is as cheap as wind and solar wish they could be. Some of the math is here: http://www.roadmaptonowhere.co...

We need to do this quick, and it has to make economic sense or it won't happen, and renewables offer massive opportunities for jobs and growth.

I agree, we must be quick. That's why we need to build wind, solar, hydro, geothermal, AND nuclear. If nuclear is not included then the world will fail to meet any CO2 reduction goals declared by the United Nations. Nuclear power makes economic sense. Any problems of costs for nuclear power are NOT in engineering, materials, or labor. The only costs associated with nuclear power that might make it uneconomical is political and regulatory. China figured out how to make nuclear power economical. One thing they do to keep costs down is shoot any protestors that hold up construction. I'm not saying we should do that in the USA but we can keep them from filing frivolous lawsuits and imprison them for their dangerous antics that interfere with solving this problem.

I saw in another thread someone claiming (jokingly I assume) that Greenpeace is causing global warming. Well, that's not far from the truth. The science shows that nuclear power would allow for a significant reduction in CO2 production, but Greenpeace opposes this. The science shows that cutting down trees for lumber, and planting new trees in their place, would create a considerable carbon sink for the CO2 we already produced, but Greenpeace opposes this.

Science tells us we need nuclear power or we will fail to reduce our CO2 in any meaningful time frame. That's why we need nuclear power. We need to include nuclear power in our solution to reduce CO2 or we will see CO2 output grow with all the global warming that comes with.

IT'S SCIENCE!! Are you a science denier?

Given the solar potential of that area of the world, they could use solar thermal to power the desal plants, mine the brine for lithium and magnesium and use the sodium & potassium salts for thermal energy storage

Taking the whole area of the Middle East, the population there, the solar power available, and the drinking water that solar power could produce, then I would agree that solar thermal is possible as a solution. There's a huge problem, the people in the Middle East are a bunch of groups that don't get along very well. Politics prevent this from being feasible.

First, solar desalination is a big fat valuable target in case of war or terrorism. You can't put a solar collector in a bunker and expect it to work. Maybe you can build it from bulletproof glass and such but it's still a big target if it's to collect enough sun to matter. Second, some of these nations are small with not a lot of open area for solar collectors. To get enough sun they'd have to "import some sun" from their neighbors in the form of desalinated water, electricity, or something else of value. This means trade with people that might just rather see them dead, and also having something of value to give in return. What would these nations have to trade? Other than the oil and natural gas that we'd rather not see burned?

I could go on but I hope I've made my point. This is not a problem that can be solved with solar power given the politics. That's even assuming the physics and economics work out. To convince them to switch to solar power you'd have to show them it can make them money, or be less of a money sink than using oil, natural gas, or nuclear power. I've seen the math and even in sunny UAE they cannot rely on solar power to provide the electricity and drinking water they need. They will have to use nuclear power or revert to a stone age existence in time.

Some sources:
https://www.withouthotair.com/
http://www.roadmaptonowhere.co...
http://cmo-ripu.blogspot.com/2...

Get a damn clue.

Then clue me in. I asked a very honest question with sincere curiosity. Germany has stated an intent to reduce its CO2 output by closing coal fired power plants. I see that is happening. What is also happening is the construction of new coal fired power plants. What is the capacity of these old plants compared to the new? Is this just closing down two coal plants only to build a new one that's twice their size, and therefore changing nothing in how much coal is burned?

I cannot take a nation's commitment to reduce CO2 output when that same nation has a commitment to abandon nuclear power. While it may be possible to do both it will be quite difficult as shown on this web page:
http://cmo-ripu.blogspot.com/2...

And this website:
http://www.roadmaptonowhere.co...

And this website:
https://www.withouthotair.com/

And here:
https://www.brightnewworld.org...

I see plenty of people on Slashdot talking about how solar power is inexpensive today, but no one seems to actually say how much it costs. Let's see some numbers. But first I'd like to see the numbers on coal power, because that's the biggest producer of CO2. Replace coal with most anything else and CO2 output is reduced. I'm not seeing Germany even doing that, and if someone could help me find some numbers then I'd appreciate that. Numbers of plants closed and opening is meaningless without knowing the size of the plants. Put it numbers my 11 year old nephew can understand, he wants to be an engineer some day.

Nuclear power.

When I see new nuclear power plants getting built then I will believe that politicians and the public are taking global warming seriously. I have read some encouraging news recently that US federal regulators are making real investments in the future of nuclear power. There's already been a shift in how nuclear power is viewed, and people are starting to embrace it again. One real reason people are embracing it is very self serving, a lot of nuclear power plants are reaching end of life and will be shut down soon and without a new reactor in its place a lot of jobs will be lost as well as a large source of electrical generation capacity in that region.

I don't much care why people are embracing nuclear power, only that people embrace it. Nuclear power is safe, low carbon, domestically sourced, and inexpensive.

Say what you will about past accidents with nuclear power, like Fukushima, Chernobyl, and Three Mile Island, all of them are irrelevant to embracing third and fourth generation nuclear power. All of those past accidents were with second generation nuclear, and as safe as second generation nuclear power has been on the aggregate we will see even safer power with third generation nuclear that is being built now. Fourth generation nuclear, such as molten salt reactors, will be safer still.

I've seen the numbers and models on a national grid based on wind, water, and sun. This is not a future with inexpensive, reliable, and safe electricity. It's quite likely not low in CO2 either. There is no future with inexpensive, plentiful, safe, clean, and "green", electricity that does not include nuclear power.

Here's a couple websites that do the numbers:
http://www.roadmaptonowhere.co...
http://withouthotair.com/

As an engineer, his book is the only thing worth reading on energy. It's all math which turns most people off because if you disagree with him you have to show why.

The simple fact is that nuclear is really the only energy technology that can reliably fill the growing need for energy.

Technically you're right, but only if we develop both reliable industrial-scale breeder reactors and the technology to extract seawater uranium on a large scale. There's just not enough U235 to generalize the use of nuclear energy on a worldwide scale, so we need breeders to burn U238, and get more of it than current reserves. Not sure about thorium reserves, but that would also require breeders. But indeed, with the aforementioned technologies we can sustain some growth, though not indefinitely. Further down the road, the only technology I'm sure would leave room for lots of growth is deuterium fusion; not deuterium-tritium (which would need to tap into lithium reserves to make tritium) but deuterium-deuterium, which is of course harder and much, much less certain than fission with breeder reactors.

What makes your point correct is that, although renewables can probably sustain us at current consumption rates, they won't allow for any significant growth. OTOH, any significant growth with any energy source will incur lots more waste heat, which would compound global warning. I don't have numbers for how waste heat would compare to current greenhouse-gas emissions in terms of warming the planet. But the numbers supporting my post can be found in Sustainable energy without the hot air, a bit dated but still a must-read.

This book, Sustainable Energy Without the Hot Air, although a bit dated, is a good reference on how much energy we actually consume, and what can possibly be produced with renewables and others. The conclusion agrees with TFA: North America probably can live on solar, wind and enough storage. Not that easily, but it seems possible.

That didn't seem right at first glance to me, so I've run the numbers:

So did this guy and he came up with a different conclusion:

https://www.withouthotair.com/

The land area of the UK is estimated to to be 241,930 square kilometres, so we're looking at around 1.5% of the total land area of the UK covered in solar panels.

You assumed 1kw/m^2 which is wildly wildly optimistic.

Firstly, solar panels are about 15% efficient. Secondly, the UK is at 51-59 degrees North. And cloudy some of the time. And there's this thing called "night". London receives between 0.52 kWh PER DAY per m^2 in winter, and 4.75 in summer.

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

The largest bit of uninhabited, unfarmed land (the Highlands) is nearly on the same latitude as Anchorage, AK.

so we're looking at around 1.5% of the total land area of the UK covered in solar panels.

Except you're about 2 orders of magnitude in your efforts and now it requires over 100% coverage of the land area, which leaves no room for anything else like crops which currently covers 70% of the land area.

lots of rainy mountains in Scotland and Wales)

Not really, no. It's a bit hilly but nothing at all like Norway. With 100% perfection you'd make 1kWh per hour per person.

Anyway read the book it's full of the kind of calculations you are interested in.

The UK is surrounded by sea for offshore turbines and almost every roof could have solar and storage (home and plugged in EVs) which can be linked together via microgrids.

It's still not enough.

we can run our civilization for 10000's of years with nuclear. That makes is sustainable. If we include seawater extraction and thorium we can run our civilization for millions of years.

According to http://withouthotair.com/ it's more like a few thousand years with seawater uranium extraction and breeder reactors (and maybe thorium). Without those technologies, uranium reserves would only last a few decades. And that's assuming total power consumption remains stable.

What stunned me further is that even deuterium-tritium fusion doesn't do better. It takes deuterium-deuterium fusion, if we ever manage it, to last millions of years at current consumption rates.

I suspect at some point we will have hydrogen fuel cells.

What? We already have them. Oh, you mean in cars. That's not happening. Hydrogen is very difficult to store and transport, unless bound chemically to something else. I'll get back to that.

The storage of the hydrogen is likely to be the killer app for carbon nanotech, as we don't want to substitute one waste of metals for another.

The best way we have to store hydrogen now is when bound to something else. Water works well to "store" hydrogen, as in being bound to an oxygen, but that's not much for a fuel. Binding hydrogen to a nitrogen or carbon works well as a fuel though. There's a reason why there is so much research into fuel cells that can run on methane and methanol, it's easier to solve the problem of extracting the hydrogen from these chemicals than to store pure hydrogen. The great thing about storing hydrogen by binding it to a carbon, we've been using hydrogen bound to carbon as fuel for a very long time. If we can make hydrogen cheap enough to use as a fuel then we can bind it to carbon and use it immediately as a fuel, no fuel cells needed.

The hydrogen can be generated in situ at home or the filling station with wind or solar power, so no dangerous tanks like with gasoline.

If you think that handling hydrogen is easier and safer than handling gasoline then I'm staying very far away from you. The hydrogen tanks will not be eliminated, the car has one. The car will need one if the fuel cells are going to propel the car.

Also, if you think that wind and solar is going to work for filling up a car for a daily driver then I suggest you check your math. Someone did do the math and it's not an easy problem to solve.
http://withouthotair.com/

Any biomass fuel is terrible at converting sunlight into energy we can use.
In comparison to what?

In comparison to anything else.
Biomass fuels get at best 2 W/m^2 in the most ideal conditions, more like 0.5 W/m^2 for much of the world.
Photovoltaic gets about 5-20 W/m^2
Wind is not much better than biomass at 2 W/m^2
http://withouthotair.com/c18/p...

Nuclear is about 1000 W/m^2
http://withouthotair.com/c24/p...

Much of Europe consumes energy at a rate of about 1 W/m^2. This is an easy calculation, just take the national energy consumption and divide by the area. If a western nation is going to maintain it's standard of living, and get that from biomass, then it will fail. There just is not enough land per person in those nations. That's just land needed for energy, people would still need land for the growing of food.

Using wind to power most any European nation means covering half of the nation with windmills. Photovoltaic energy still means nation sized areas covered in solar collectors, taking up 5% of the area with ideal conditions but more like 20% with more realistic collection.

If you want energy that is "green", and have any kind of energy independence, then there is going to have to be some use of nuclear power. Relying on foreign oil (such as from the Middle East), or natural gas (such as from Russia), or even running electric lines under the Mediterranean Sea to collect the plentiful sun from Northern Africa means Europe will be at the whims of foreign nations for its energy.

Larger nations with lower population densities, like the USA, Russia, Canada, China, and Brazil, have enough land and diversity of geography to get sufficient wind, solar, and hydro to meet domestic needs if they must. This means avoiding biomass fuels as that is a waste of land area, and even then some reliance on more energy dense sources of energy like natural gas (not ideal but better than oil or coal) or nuclear.

Since the goal is to replace oil, such as for use as fuel for cars, then we need to account for current electrical needs, current energy use from oil, and account for any growth due to population increases. Sure, some efficiency gains can bring this down, but it's not going to get close to what biomass can provide unless a nation uses as little energy as some Third World nations.

Any biomass fuel is terrible at converting sunlight into energy we can use.
In comparison to what?

In comparison to anything else.
Biomass fuels get at best 2 W/m^2 in the most ideal conditions, more like 0.5 W/m^2 for much of the world.
Photovoltaic gets about 5-20 W/m^2
Wind is not much better than biomass at 2 W/m^2
http://withouthotair.com/c18/p...

Nuclear is about 1000 W/m^2
http://withouthotair.com/c24/p...

Much of Europe consumes energy at a rate of about 1 W/m^2. This is an easy calculation, just take the national energy consumption and divide by the area. If a western nation is going to maintain it's standard of living, and get that from biomass, then it will fail. There just is not enough land per person in those nations. That's just land needed for energy, people would still need land for the growing of food.

Using wind to power most any European nation means covering half of the nation with windmills. Photovoltaic energy still means nation sized areas covered in solar collectors, taking up 5% of the area with ideal conditions but more like 20% with more realistic collection.

If you want energy that is "green", and have any kind of energy independence, then there is going to have to be some use of nuclear power. Relying on foreign oil (such as from the Middle East), or natural gas (such as from Russia), or even running electric lines under the Mediterranean Sea to collect the plentiful sun from Northern Africa means Europe will be at the whims of foreign nations for its energy.

Larger nations with lower population densities, like the USA, Russia, Canada, China, and Brazil, have enough land and diversity of geography to get sufficient wind, solar, and hydro to meet domestic needs if they must. This means avoiding biomass fuels as that is a waste of land area, and even then some reliance on more energy dense sources of energy like natural gas (not ideal but better than oil or coal) or nuclear.

Since the goal is to replace oil, such as for use as fuel for cars, then we need to account for current electrical needs, current energy use from oil, and account for any growth due to population increases. Sure, some efficiency gains can bring this down, but it's not going to get close to what biomass can provide unless a nation uses as little energy as some Third World nations.

They likely didn't consider ethanol powered cars because ethanol is a terrible fuel. Thailand is a tropical nation and so can grow plants that are more efficient at converting sunlight into fuel. Much of the rest of the world is not so lucky. Here's some data comparing the different plants:
http://withouthotair.com/c6/pa...

Any biomass fuel is terrible at converting sunlight into energy we can use. Why it's being used so much now boggles the mind. The math is not hard to figure out. We'd be better off using that land for solar panels to charge batteries. Even better is using that land to grow food and look for energy from somewhere besides the sun. Where would be a better place to go for energy? Anywhere. When food competes with energy then you'll have people needing to decide if they will have to cut down their apple tree for firewood and risk starvation in the summer, or keep the tree and risk freezing to death in the coming winter.

You can claim some future advancement in genetically engineered crops and/or better biomass conversion will change this but that's not going to happen in ten years. Go ahead and try, but I think we'll need a backup plan.

Why not biofuels? No nasty radioactive waste to deal with.

Because bio-fuels don't add up.
http://www.withouthotair.com/c...

I think one conclusion is clear: biofuels canâ(TM)t add up â" at least, not in
countries like Britain, and not as a replacement for all transport fuels. Even
leaving aside biofuelsâ(TM) main defects â" that their production competes with
food, and that the additional inputs required for farming and processing
often cancel out most of the delivered energy (figure 6.14) â" biofuels made
from plants, in a European country like Britain, can deliver so little power,
I think they are scarcely worth talking about.

The problems of nuclear waste is not only solvable but largely already solved. Encasing the waste in glass and burying it in the ground is a completely viable solution.
http://www.withouthotair.com/c...

Why not biofuels? No nasty radioactive waste to deal with.

Because bio-fuels don't add up.
http://www.withouthotair.com/c...

I think one conclusion is clear: biofuels canâ(TM)t add up â" at least, not in
countries like Britain, and not as a replacement for all transport fuels. Even
leaving aside biofuelsâ(TM) main defects â" that their production competes with
food, and that the additional inputs required for farming and processing
often cancel out most of the delivered energy (figure 6.14) â" biofuels made
from plants, in a European country like Britain, can deliver so little power,
I think they are scarcely worth talking about.

The problems of nuclear waste is not only solvable but largely already solved. Encasing the waste in glass and burying it in the ground is a completely viable solution.
http://www.withouthotair.com/c...

• North America does have enough sun (and deserts) to live entirely on renewables; Europe doesn't, though a Europe+North Africa block could; it doesn't say about China, which has deserts but also a much larger population. The book dates from 2009, meaning it didn't anticipate photovoltaics' improved efficiency, which helps. Wind power can also provide a significant part of the required power, though not all.
• Nuclear isn't renewable, but assuming you want it to last 1000 years at current consumption levels, you need both breeder reactors and an industrial-scale process to extract uranium salts from the ocean, otherwise you can't provide more than a fraction of the required power for the world's population with known uranium reserves — and that's without population or consumption growth. Not sure about thorium, but I think that uses breeder designs anyway. As for fusion, even deuterium-tritium fusion doesn't cut it; we can only hope to manage deuterium-deuterium fusion someday, in which case we'll be home free with lots and lots of margin.

I do agree that, to prevent a global catastrophe, we must decarbonate the world's entire economy as fast as possible, which requires:

• Phasing out all gas-based transportation in favor of electric vehicles (EVs); both cars and trucks. In turn, this requires...
• A several-fold increase in total electricity production even while phasing out gas- and coal-powered power plants. For this, we need a massive deployment of solar or nuclear, preferably both and preferably nuclear breeder reactors (which will take a long time, so start ASAP, and deploy solar in the meantime).
• Overhauling the power grid to reliably handle the extra load. Also, in an all-renewables scenario, storage is required to smooth out variations on production and consumption. The book suggests using the new EVs' batteries, which requires cooperation from people and/or a very smart grid and market (make electricity costs fluctuate in real time even for home users).
• Massively improve buildings' and homes' insulation, and replace existing heating systems with heat pumps (which can double as air conditioners when it's hot). Yes, current heating systems consume almost as much on a global scale as ground transport.
• Air transport is a huge problem, because there's a minimum required energy to keep a plane aloft, and we're almost already there. Right now it's fortunate that most of the world's population doesn't fly as much as that of developed countries, but that's bound to change, which would result in completely unacceptable CO2 emissions; biofuels would help, but it's not clear whether we can produce enough. The book proposes zeppelins (efficient but way slower). I propose hydrogen planes (if they can be made safely). In the meantime, air travel should be actively discouraged.

One could argue that the above measures are too disruptive and require too much cooperation at every level (from worldwide to individuals) to be realistic. That means that we should also research ways to mitigate the catastrophe:

• Increase agricultural productivity in hotter conditions.
• Find ways for population to stay alive in places that will become unhinabitable due to the heat (underground cities?)
• Build dams against rising sea levels, hurricane-proof coastal areas.
• Promote reducing the population, handle population aging.
• ...
• Profit! And in fact, those are economic opportunities, aren't they? King of like the broken-window fallacy, but what if you can't avoid breaking the window?

The vast majority of worldwide solar is likely going to be concentrated solar in the world's deserts. Yes, there are a few beetles and scorpions that might have a few more shady places to rest during the day.

An extremely good, and free, e-book on climate change recommended this solution in 2008. The author, David MacKay, was the Chief Scientific Advisor to the Department of Energy and Climate Change (UK).

Here's the book - I thoroughly recommend it: Sustainable Energy - without the hot air.

It attempts a quantative approach to determining whether particular alternative sources of energy are useful and sustainable or not. It's a short read, politics free (neither "bah, it's all a hoax!" nor "do this immediately or DIE!") and is definitely worth the time of anyone interested in the subject.

That's the problem with skimming the book, looking for reasons to doubt it.

The section you linked to was part of the "technical chapters" that was explaining how to convert a "long distance" flight to standard units of energy, and then to contrast that with the amount of electrical energy that would need to be generated. He has several such chapters on various bits (cars, wind generation, etc) and will use them as examples of a potential "stack" of energy use or generation.

But when he talks about actual usage, he uses official numbers. For instance, his 125 kWh/person/day in the U.K. is an official number from UN and U.K. sources (footnoted here). The US figures come from the UNDP source. He has a nice chart (18.4) that compares dozens of countries energy consumption vs GDP. All the chapters are extensively footnoted (at the end of each chapter).

It's an extremely well-reviewed book with glowing reviews from academia, the science press, serious mainstream newspapers, Bill Gates and Cory Doctorow. It's probably the best sympathetic but cold-eyed view at what going carbon free really means.

That's the problem with skimming the book, looking for reasons to doubt it.

The section you linked to was part of the "technical chapters" that was explaining how to convert a "long distance" flight to standard units of energy, and then to contrast that with the amount of electrical energy that would need to be generated. He has several such chapters on various bits (cars, wind generation, etc) and will use them as examples of a potential "stack" of energy use or generation.

But when he talks about actual usage, he uses official numbers. For instance, his 125 kWh/person/day in the U.K. is an official number from UN and U.K. sources (footnoted here). The US figures come from the UNDP source. He has a nice chart (18.4) that compares dozens of countries energy consumption vs GDP. All the chapters are extensively footnoted (at the end of each chapter).

It's an extremely well-reviewed book with glowing reviews from academia, the science press, serious mainstream newspapers, Bill Gates and Cory Doctorow. It's probably the best sympathetic but cold-eyed view at what going carbon free really means.

First, we need to drop our average per capita energy usage from 250 kWh/day to 125 kWh/day.

That number seems wrong. I looked at his website (the design is Geocities, circa 1998 - nice!) and it's not immediately obvious where that number came from, but it appears to be too high. In 2015 the US generated 4,077.6 TWh of electricity so that's around 35 kWh per capita per day. That year 3.22 trillion miles were driven, if everyone magically had a Telsa Model S (which uses 340 wh/mi, smack dab in the middle in efficiency for electric cars listed by the EPA) instead of their current car that would be another 9.3 KWh per day per capita.

So that's around 45 kWh for electricity and transportation, where does the other 205 kWh come from? Heating? The electricity number already includes all the electric heating (as well as commercial and industrial use) so it would just be oil and natural gas - do those really add up to 205 kWh? We used 27.3 trillion cubic feet of natural gas, but a ton of that is already included in the electric number. According to the EIA it was closer to 15 trillion for residential, commercial and industrial use. That would be another 38 kWh. We burned around 390 billion gallons of heating oil, that's another 1.5 kWh. I don't necessarily think that converting the total heat available in those substances to kWh is a valid comparison but let's ignore that for now. We are still only to 84 kWh per person per day, where is the missing 166 kWh?

Looking further on his site I think I see what the issue is. He just makes up numbers and then adds those to his total. For example, on this page he guesses at a number for kWh per airline passenger and then rather than using data like actual miles flown he just assumes every person makes exactly one intercontinental trip (from London to Cape Town) per year and extrapolates a 30 kWh usage for that. He does similar things throughout the site, instead of using actual consumption data he makes estimates based on broad assumptions. I'm sure he has interesting things to say but there's certainly no rigor in his numbers and it's a poor site on which to base a numbers post.

Actually, it doesn't completely add up, for a couple of reasons.

First, Musk is (semi-purposely?) conflating the area required to generate the same amount of electricity that the US uses each year with the amount of energy that the US uses. Second, he's talking about the square footage of panels, not the square footage of any reasonably designed panel array (multiply that number by 4).

The late physicist David MacKay, an adviser to the UK's Department of Energy and Climate Change and author of the great "Sustainable Energy - Without the Hot Air" book and website, worked the numbers and came up with the following figures to totally wean the US off of fossil fuels.

First, we need to drop our average per capita energy usage from 250 kWh/day to 125 kWh/day. He's assuming some of this will occur due to electrification of transport but was skeptical we could get completely down there, but assumed for the sake of argument that we could.

We start out needing to build out 2600 GW of wind power. This is 200 times the amount we had at the time and would cover an area about the size of California. That provides about 42 kWh / day / capita.

We then build out offshore wind for most of the shallow waters surrounding the country. This provides about 4.6 kWh / day / capita.

We then build out our hot-rock geothermal potential over 50 years to get another 8 kWh / day / capita.

Hydro currently supplies about 3.6 kWh / day / capita. There isn't a whole lot of capacity left but he generously allows us to double it to 7.2 kWh / day / capita.

That only gets us to 62 kWh / day / capita. You're going to need about 13,225 square miles (a 115mi x 115mi square) of concentrating solar power to supply the rest.

But that doesn't sound good - all of California covered in wind farms, all of the near-coast also covered in wind farms, thousands of hot rock geothermal wells plus 13,225 sq mi of CSP in deserts. And that only gets you to half of what we're currently using and we haven't even talked about batteries...

OK, scrap that plan. Let's just go to CSP in deserts - it's about the best renewable resource and you can build in molten salt reservoirs to provide nighttime energy - no need to build out all those batteries. And let's be realistic - the US isn't going to significantly drop its energy use as its population continues to grow, so let's peg that at the current levels.

You now only need a 139,000 square miles of CSP to provide our 250 kWh / day / capita energy use. Hurray! That's only all of Arizona (114,000 sq mi) and a big chunk of New Mexico...

Algae fuel is experimental. People have done hydrocarbon synthesis for a very long time. The only switch on this process is using nuclear power to drive the process. We've been doing nuclear power for a long time too, but there's a lot we can gain yet on that.

So, sure, go do that algae experiment and see how that works out. I have an idea on how well that would work out because Dr. MacKay did the math on that too.

http://www.withouthotair.com/c...

The best you can get from solar power is about 1000 W/m^2, that's a top limit. The processes we have to convert that sun into useful energy are incredibly inefficient. And, again, there is a top limit based on the area and if we can only extract 10%, 20%, or 30% of that then that is a lot of area needed. Nuclear power today gets ten times the power by area, and we've only started on that. 1000W with maybe 1500W on the top end for solar compared to 1000w on the bottom end for nuclear and any form of solar, including algae, cannot compete.

I used to think algae was a great idea too, but then I saw the math.

While it is true that running a car off of bio-fuels is potentially low carbon what it is not is sustainable. We simply do not have enough land to grow both our food and our fuel.

https://www.withouthotair.com/...

I think one conclusion is clear: biofuels can't add up - at least, not in
countries like Britain, and not as a replacement for all transport fuels. Even
leaving aside biofuels' main defects - that their production competes with
food, and that the additional inputs required for farming and processing
often cancel out most of the delivered energy (figure 6.14) - biofuels made
from plants, in a European country like Britain, can deliver so little power,
I think they are scarcely worth talking about.

What does seem viable is the seawater to jet fuel system that the US Navy is working on. By using nuclear power and some pretty basic chemistry we can get zero carbon fuel.

http://www.businessinsider.com...

Give me all the bullshit you like about nuclear waste scaremongering but here's the deal, nuclear power works now. This seawater to fuel technology works now. This does not require any new technology and 90% of the infrastructure to make this replace fossil fuels already exists by virtue of it being a hydrocarbon, just like the fossil fuels.

We could be zero carbon in just a few decades if we went on this track, and 99.9% of the population would not even know it's happening. We'd need to issue nuclear power licenses at a rate of two per month in the USA to do it. That might sound like a lot until you compare it to how many cornfields, solar panels, and windmills it would take for the same energy.

It doesn't need to, which you would have realized if you had taken your own advice and rewatched the video you linked. The TED Talk specifically said that rooftop installations in England were getting 20W/m^2, 4x the number you quoted (which was for solar parks in England). At those numbers, home-based installations would only need to cover 5% of England in order to achieve 100% coverage of the country's energy needs. And that's ALL of the country's energy, including transportation, businesses, and home use.

Yes, of course, my mistake. I did see on his website a caveat that such efficiency in current solar panels would be impractical for mass deployment because of excessive cost.
https://www.withouthotair.com/...

While it can be done, using only solar power from 5% of the nation's area, it would mean energy prices would quadruple. Keeping energy within sane prices AND using only solar would mean needing 20% of the nation's area covered in solar panels. This assumes stable prices for everything, which is impossible if demand for fossil fuels drops to zero and demand for solar goes to... I don't know, 1000 times current demand?

Even if the rest of the world was covered in England's stereotypically gloomy weather, they'd only need to have rooftop installations covering 0.7% of their land area.

I don't know why the cost of these alternatives were not mentioned in the video but they are important to discuss, perhaps the matter of cost was cut from his speech due to time constraints. He mentions this as impractical on his website. He also did not claim that any one "lever" to a carbon free future is all we should choose, only that declaring one less desirable means pulling harder on the others. I agree with this. Solar power alone cannot solve this for many reasons, the area needed is a problem, which is just one of many things that contribute to the cost.

And that's before we even get into the efficiency gains that have occurred in the five years since he gave that talk, not to mention the fact that the sun's rays are far weaker in England than they are in much of the rest of the world.

I'm not going to fret too much over the math here since we are trying to get an order of magnitude idea of the problem. You might say that covering 1% of the world in solar panels is trivial but it is not. That is a lot of area to cover and this does not include issues of storage, transport, cost, or the political issues of relying on neighboring nations for a vital resource like the energy needed to heat your homes. Ask Europe about how well relying on Russian natural gas has gone.

Efficiency gains in solar power have not been what they used to. We've not seen much gains in efficiency, but prices have gone down for the same efficiency of panels. Sadly we won't see an update on this from Dr. MacKay as he died last year.

Maybe I botched the math somewhere, but this doesn't seem nearly so far fetched as you're trying to suggest, especially since your one and only source directly contradicts your claims.

Again, not going to argue on the order of magnitude math too much. Whether this is a Texas sized problem, an Alaska sized problem, or one the size of Ohio, this is still a big problem. I see no contradiction, except perhaps in that the information provided is incomplete. The TED talk was intended to be a bird's eye view of how to address this issue, and I believe he did an excellent job. He did such an excellent job that I'd argue that one should not need another source. He gave real world numbers to make his case, and gave very conservative estimates of potential gains when extrapolating to the near future. Science is not a matter of popular opinion, it's a matter of who has the best evidence. Dr. MacKay gave plenty of evidence on his website.

All of which is to say, yes

In an analysis done by the English physicist David McKay, he goes into some detail about how the US is one of a very few countries where solar and wind could provide 100% it its energy needs keeping the current standard of living. This is based purely on available energy in the environment and ignores everything else.

Feel free to point out errors in the analysis.

Does he mean ignoring things like chopping up endangered species of birds and bats, destroying delicate desert habitats and such?

Feel free to point out errors in the analysis.

You need about 50 nuclear reactors the size of Sizewell B (1.2 GWe) to get to 1/6th of the current net energy use of the UK. We're not talking about just electricity but replacing all hydrocarbons (fuel for transport and industry, embedded energy from imports). MacKay actually assumed some fairly significant efficiency gains from electrification and technological advances, enough so that those 50 plants might handle a full third.

If you want to read a short and informative (but depressing) page that goes into what you can actually achieve with renewables based on solid physics, read this,

Possibly because most solar / wind advocates (which I am all for) hand wave away the scope problems. Solar and wind are extremely energy diffuse - you need a lot of land to gather the amount of energy of even a modest coal or gas plant.

I'm a big fan of David MacKay's (RIP) work - Without the Hot Air. He, like me, wanted to move to a decarbonized energy economy but he worked out the hard numbers and showed the magnitude of the scope involved. Just to get to 1/6th of the current consumption of UK energy, you need wind farms covering the entirety of Wales - every square foot would need to be within a few hundred meters of a wind mill.

He advocated large-scale energy efficiency measures to try to drive down that amount, but even dropping the UK energy consumption in half (which is already nearly half of the US per capita) still results in a Wales sized wind farm supplying only a third of the power required. Solar within the UK was basically a non-starter in terms of total impact, but if you created a solar farm twice the size of Greater London in the Sahara, you could get another third. Add another 50 of the largest possible nuclear plants and you reach your no-carbon goal.

But all of this assumes enormous efficiency gains. If the efficiency stays about the same, double those numbers. Technology has gotten somewhat better since he died, but not enough to significantly change the numbers.

Hear, hear. The people telling you that "It's better to switch to a diet of energy conservation, efficiency, and renewables" are completely out of touch with reality. While the first world is busy sprinkling their landscapes with renewables and prematurely shutting down nuclear plants, the global share of clean energy is actually declining, and the reason is quite simple: growth. Before advocating unrealistic solutions based on ideology, please educate yourself.

There are already billions doing without, burning dung and wood just to survive; telling them that they can't have a better life is insulting. The developing world will choose the most economical option, and today that is coal. They desperately need cheap, abundant, and reliable energy to build out infrastructure and industry. It is our job to push technology, as only a better option will dissuade them from realizing the mountain of coal plants currently on the drawing board. Once built, they will continue to burn coal for the next 40-60 years.

Molten salt reactors were proven 50 years ago, and can solve the problems facing conventional nuclear. The primary obstacles are political in nature, and while it will require courage, they can be overcome. There are dozens of companies trying to push nuclear forward, but they are mired in overzealous regulations and unfair policies distorting the market in favor of renewables only and not clean energy in general. In reality, these policies lock in fossil fuel backup, which will remain the bulk of generation. Only when reactors are rolling off of assembly lines, do we have any hope of truly closing the book on fossil fuels. Until then, it is foolish to leave any effective clean energy options off the table.

(Also note: the Bulletin of the Atomic Scientists is an anti-nuclear organization; leading climate scientists, among others who genuinely care about the environment, do not exclude options based on the "green" ideology.)

Let's conside London, since that was under discussion. Consider how diving in London would be if: (a) the tube was switched off (hint: a tube strike) (b) with the tube operating as normal The existence of mass transit has a direct, positive effect on the use of private tansport.

(1) You're arguing there that transit subsidies have a positive effect, not that they don't exist. (2) Ending subsidies for London transit wouldn't abolish it, it would simply force Londoners to pay the true cost of what they actually use.

This figures I quoted included the complete power use including station lighting, escalators etc etc etc. Try again, bucko!

You need to read and understand what you cite, "bucko". Not only does MacKay fail to account for non-propulsive energy usage, his argument isn't even about actual energy usage of the London subway system, it's an estimate of what a system might achieve under "ideal" conditions and if they are willing to give up the flexibility of a private vehicle.

Yes, a net flow of money from X to Y does indeed demonstate that Y does not subsidise X. The net flow of tax money is from London outwards, so London subsidises the rest of the UK, much like the blue states subsidise most of the red ones.

Sorry, but net flows of tax money tells you little about net subsidies; you need to look at what the money is spent on and who benefits, as well as opportunity costs. For example, my state gets tons of federal funding for crap we don't want; that isn't a "subsidy" of the state.

Mostly I'm arguing for policies so the tanspot system affecting the daily lives of 10 million people doesn't collapse.

Indeed, that's what you're actually doing: trying to find arguments to justify the conclusion that the subsidies need to keep flowing. And you're right: eliminating subsidies overnight would be a disaster for London. But that merely means that Londoners have become dependent on subsidies, not that the subsidies are good.

That's why, as far as the US is concerned, it's best for cities to avoid getting into the unenviable situation the the UK and London are in in the first place.

This guy wrote a book on energy policy using nothing more complicated than high school physics, yet it's incomprehensible to most people who've supposedly have taken at least a year of physics.

I've always felt an advocate should be more critical of the cause he is advocating than the average lay person. Presumably he is more knowledgeable about whatever it is he is advocating, and thus able to see more of the flaws, problems, and drawbacks than the average lay person. If someone only posts in favor of what they are advocating while only critical of alternatives, they are merely advocating their bias, not the cause.

That's why I'll often ask people arguing for something to do their best to argue against it, or vice versa. That'll quickly reveal if the person has a good handle on all the pros and cons of both sides of the issue, indicating that they've made an honest attempt to research it before arriving at a conclusion. Or if they've come to a conclusion first and have just memorized only facts and arguments which support their position.

As best as I can tell, mdsolar has never met a solar installation he didn't like. I'm not sure "troll" is the proper classification, but it's pretty close. If you are seeking a messenger to deliver unbiased and even-handed facts and figures, he is not it. If you genuinely want an even-handed overview of the different energy sources, their advantages, and their drawbacks, I'd recommend David MacKay's web book. I should warn you though, it actually requires you to read, comprehend, and think about the trade-offs. There are no "X is good, Y is bad" one-liners.

http://www.withouthotair.com/

We have been working on grid energy storage for well over 30 years. And we still don't have a solution. What evidence do you have that it will be solved in just a few years? And well i don't think you understand the scale of energy needs. Right now there is no way in hell you could replace base energy with solar or wind or both even if all you do is build solar and wind in decades let alone a few years. Since you need a fuckton of it *everywhere*. Really run the numbers.. http://www.withouthotair.com/

This goes a long way to answer your question, but requires 3 hours of reading and a thorough` understanding of eighth grade math. It was written by a physicist and contains a lot of numbers. No algebra is required, but it does have a lot of numbers. Most people don't like numbers because they can't argue against them. No science or sociopolitical knowledge is required as there are no moral judgements made, just numbers.

Thanks for that, I'll check it out. I think one of the biggest issues people forget is the amount of energy that goes into mining Uranium in the first place. Below 200grams U per ton of rock Nuclear is no longer viable due to energetic requirements to get the fuel in the first place. That's even before the energy expenditure on the disposal of the reactor at the end of it's service life.

I think we are at the end of the once through reactor fuel cycle for that reason and burner reactors aren't really viable until materials technology catch up.

This goes a long way to answer your question, but requires 3 hours of reading and a thorough` understanding of eighth grade math. It was written by a physicist and contains a lot of numbers. No algebra is required, but it does have a lot of numbers. Most people don't like numbers because they can't argue against them.
No science or sociopolitical knowledge is required as there are no moral judgements made, just numbers.

Scotland plans to be 100% renewable by 2020, but only by generating 200% of what it needs with half from renewables and exporting the excess.

Well, that sounds like more SNP massive head-in-the-clouds wishful thinking to me.

http://www.withouthotair.com/s...

Page 2 contains a chart for the whole of britain. Cover tthe entire south facing country's roofs with solar panels. Put wind farms on over the top 10% of windiest land and put 500km of wave machines along the roughest parts of the coastline. And that matches about 50% of the UK's energy use. Those levels of coverage are truly astronomical.

There's no figures just for Scotland, but it's about 10% of the size populationwise, so let's say 10% energy use. Even if you're generous be generous and assume all of the windiest land is in Scotland, as are the waviest costs. And let's ignore solar. Scotland has very roughly half of the land area of England. They'd have to cover about 2% of their entire country with wind turbines and much of that is very wild and inaccessible without the infrastructure for such a major undertaking, and cover about 10% of their coastline with technology that doesn't yet exist[1].

That's theoretically possible, but given it would take that long ust to construct the roads to the required places, it's nothing more than wishful thinking. Unless this is of course SNP speak where "entirely renewables" actually means "entirely except for ones that are too big to deal with so we ignore then" coupled with "taxes from England can pay for all of this".

[1] Practical wave power generation is still a thing of the future. We can generate power from waves easily. Making a machine which can survive 10 years in the sea and not be destroyed by the occasional huge winter storm is an unsolved problem.

- the nuclear plants require a lot of sweet water for cooling, 24/7, and the world is running out

Not really. Only once-through nuclear plants require large amounts of fresh water continuously. Most plants use cooling towers instead. Some plants don't even use water in the recirculating parts of the cooling systems (e.g. molten salt reactors).

Also, once-through reactors, if designed to do so, can use salt water instead of fresh water.

- it's pretty much unflexible regarding any peaks or lows in consumption

Only because they aren't designed to do so. You can significantly reduce the output of a plant very quickly, but you can't speed it up quickly, currently, because of the buildup of Xenon-135 as a fission byproduct, which is a strong neutron absorber, and the only way to get beyond that is to pull the fuel rods out far more than is safe, and once the uranium fission restarts, the Xenon is quickly destroyed, resulting in a rapid increase in neutron levels in the core, which would overheat the reactor before you could bring it under control.

However, there are a couple of designs that don't suffer from that problem—integral fast reactors and molten fuel reactors both allow the xenon to be separated from the fuel. And I think pebble bed reactors could also be readily made to be largely immune to this effect by cycling in different fuel pellets in while the xenon in the recently used pellets slowly decays.

- the latest generation concrete housings' carbon foorprint takes a decade to offset

I think your numbers are way off. According to David MacKay, spread over a 25-year lifespan, it only comes to about 1.4 grams of CO2 per kWh. In other words, it offsets its construction cost compared with coal in just a little over a month, by my math.

The UK has enough renewables... We have excellent wind and wave resources, and lots of existing hydro electricity.

Actually no we don't.

http://www.withouthotair.com/c...

We have juuuuust about enough renewables to power the country (not quite), but only with (a) optimistic assumptions about efficiency and (b) do things on a scale so vast that it would never fly.

Seriously, have a read of that book, it is very good.

Tidal is marginal at best.

http://physics.ucsd.edu/do-the...

"But my overall goal is to assess which forms of power can take on a substantial fraction (possibly up to a quarter) of our power needs. Only those sources capable of expansion at this scale stand any chance of achieving even half of that. Tidal is not one of those players."

Nuclear should be the way to go until we achieve fusion (improbable) or achieve a way to use solar/wind along with a scalable grid battery (slightly more probable but still difficult). That and natural gas which is abundant and the cleanest hydrocarbon.

We should ditch coal as soon as possible. And diesel too.

Oh, by the way, this is obligatory reading for everyone interested in this topic:
http://www.withouthotair.com/