The Remarkable Progress of Renewable Energy

[steve_bank]

I agree that a reduction in population is coming.

Hum amity will survive, it always has. The Dark Ages, The Plague. As long as knowledge of technology survives humanity will evolve into a new system or paradigm.


Wind and solar could support a smaller global population quite well.

It's not just power, but resources.

I agree. Water is already becoming an issue.

 

[Loren Pechtel]

Cost to manufactore is reflectednin codt to build. A nuke is far motre expensive in blabor, mterials, and design.

Nukes require special materials. Welding requirents are higher. Waste storage.

You think semiconductors don't have some very exacting requirements for manufacture? Far more than the physical infrastructure of a nuke plant.

The business term is total cost of ownership.

Contraction costs
Materials cost
Labor costs
Recurring costs-maintenance and any waste
Decommissioning costs--nukes have limited life

Saying materials for nukes and solar-wind both have to be manufactured is a false equivalence. If nukes were as cheap as solar and wind there would be a nuke in every town.
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Solar power can be used to make solar cells. The obvious observation.

The problem with nuke is political, not economic. And solar is nowhere near economic once you consider the actual cost of providing power--the storage problem makes it utterly uneconomic.

 

[bilby]

I agree that a reduction in population is coming.

Hum amity will survive, it always has. The Dark Ages, The Plague. As long as knowledge of technology survives humanity will evolve into a new system or paradigm.


Wind and solar could support a smaller global population quite well.

It's not just power, but resources.

I agree. Water is already becoming an issue.

You're both crazy. There's no shortage of water, nor of any other resources.

The only exceptions are fossil fuels and helium. Neither is a prerequisite for rebuilding civilisation.

In a post-disaster world, our former cities form a better source of accessible ores than any pre-industrial mining area ever did.

Where do you imagine that all this stuff mined in the last couple of thousand years has gone to?

 

[Loren Pechtel]

I agree. Water is already becoming an issue.

You're both crazy. There's no shortage of water, nor of any other resources.

The only exceptions are fossil fuels and helium. Neither is a prerequisite for rebuilding civilisation.

In a post-disaster world, our former cities form a better source of accessible ores than any pre-industrial mining area ever did.

Where do you imagine that all this stuff mined in the last couple of thousand years has gone to?

Heavy metals. We talk about hydrogen fuel cell cars--but we could only actually build enough for the US. Once.

 

[bilby]

I agree. Water is already becoming an issue.

You're both crazy. There's no shortage of water, nor of any other resources.

The only exceptions are fossil fuels and helium. Neither is a prerequisite for rebuilding civilisation.

In a post-disaster world, our former cities form a better source of accessible ores than any pre-industrial mining area ever did.

Where do you imagine that all this stuff mined in the last couple of thousand years has gone to?

Heavy metals.

What about them? Are they not subject to the First Law of Thermodynamics?

We talk about hydrogen fuel cell cars--but we could only actually build enough for the US. Once.

I am talking about rebuilding a collapsed civilisation. Hydrogen fuel cells play no part in that concept that I can see. In what way are they relevant to, well, anything?

 

[steve_bank]

Cost to manufactore is reflectednin codt to build. A nuke is far motre expensive in blabor, mterials, and design.

Nukes require special materials. Welding requirents are higher. Waste storage.

You think semiconductors don't have some very exacting requirements for manufacture? Far more than the physical infrastructure of a nuke plant.

The business term is total cost of ownership.

Contraction costs
Materials cost
Labor costs
Recurring costs-maintenance and any waste
Decommissioning costs--nukes have limited life

Saying materials for nukes and solar-wind both have to be manufactured is a false equivalence. If nukes were as cheap as solar and wind there would be a nuke in every town.
\
Solar power can be used to make solar cells. The obvious observation.

The problem with nuke is political, not economic. And solar is nowhere near economic once you consider the actual cost of providing power--the storage problem makes it utterly uneconomic.

I am well ware of what it takes to manufacture electronics. These days it is all highly automated with industry standard equipment. Other than clean rooms and vibration insulation and toxic waste disposal there are no major infrastructure requirements. Compared to the total energy budget of the USA electronics manufacturing is small.

Some of the materials are toxic. A common material is phosgene gas, a never agent.

Nukes do not solve the problem of resources like food and water. Climate change is already affecting food availability in the third world.

Economically not just new nukes, all the nukes in the USA will need to be replaced as they near end of life.

A govt study predicts the USA will cease to be a net food exporter. The LA region is heded towards a drinking water supply problem unrelated to drought.

Ca agriculture wells have gone deep enough to be contaminated by salt water. So much water has been pumped in Az the land has sunk in some places.

Nukes are both political and economic.

 

[lpetrich]

A govt study predicts the USA will cease to be a net food exporter. The LA region is heded towards a drinking water supply problem unrelated to drought.

Ca agriculture wells have gone deep enough to be contaminated by salt water. So much water has been pumped in Az the land has sunk in some places.

 Desalination to the rescue. It is, however, an energy-intensive process, with the best case of it being 3 - 5.5 kWh/m^3 from reverse osmosis. This is roughly comparable to freshwater pumped in from long distances, but locally-available freshwater goes much lower, to as low as 0.2 kWh/m^3.

One can avoid consuming a lot of water by doing drip irrigation, like with perforated hoses, and by doing xeriscaping, landscaping with dryness-tolerant plants.

Also, desalination is suited for intermittent energy sources like wind and solar -- and also for constant sources like nuclear. This is because one can easily store water that one does not need right away.

 

[steve_bank]

Saudi Arabia has large scale desalinization yet they are also buying water by the tanker. They have also attempted to tow icebergs.

Another question nobody has mentioned. It is al about greenhouse gasses.

Thermodynamically all consumed energy in the end shows up as heat. Being in a vacuum the only way to get rid of het is by radiation.

Asa rough approximation from dq = m*c*dT where q is total electric power and gasoline power consumed, m is heat capacity of air, m is mass of atmosphere what amount of energy is required to raise atmosphere 1 degree c. Assunibg nass of air much less than mass of the Erath.

 

[Loren Pechtel]

A govt study predicts the USA will cease to be a net food exporter. The LA region is heded towards a drinking water supply problem unrelated to drought.

Ca agriculture wells have gone deep enough to be contaminated by salt water. So much water has been pumped in Az the land has sunk in some places.

 Desalination to the rescue. It is, however, an energy-intensive process, with the best case of it being 3 - 5.5 kWh/m^3 from reverse osmosis. This is roughly comparable to freshwater pumped in from long distances, but locally-available freshwater goes much lower, to as low as 0.2 kWh/m^3.

One can avoid consuming a lot of water by doing drip irrigation, like with perforated hoses, and by doing xeriscaping, landscaping with dryness-tolerant plants.

Also, desalination is suited for intermittent energy sources like wind and solar -- and also for constant sources like nuclear. This is because one can easily store water that one does not need right away.

Yes, this is the real answer to much of the grid balancing problem. We need the water, we need to do something with unwanted power.

However, I must disagree on perforated hoses for drip irrigation. I've had nothing but trouble with them and have ripped out every one of them I've used. Everything now uses individual emitters.

 

[Loren Pechtel]

Saudi Arabia has large scale desalinization yet they are also buying water by the tanker. They have also attempted to tow icebergs.

Another question nobody has mentioned. It is al about greenhouse gasses.

Thermodynamically all consumed energy in the end shows up as heat. Being in a vacuum the only way to get rid of het is by radiation.

Asa rough approximation from dq = m*c*dT where q is total electric power and gasoline power consumed, m is heat capacity of air, m is mass of atmosphere what amount of energy is required to raise atmosphere 1 degree c. Assunibg nass of air much less than mass of the Erath.

This is not an important issue at current energy use levels.

 

[steve_bank]

Saudi Arabia has large scale desalinization yet they are also buying water by the tanker. They have also attempted to tow icebergs.

Another question nobody has mentioned. It is al about greenhouse gasses.

Thermodynamically all consumed energy in the end shows up as heat. Being in a vacuum the only way to get rid of het is by radiation.

Asa rough approximation from dq = m*c*dT where q is total electric power and gasoline power consumed, m is heat capacity of air, m is mass of atmosphere what amount of energy is required to raise atmosphere 1 degree c. Assunibg nass of air much less than mass of the Erath.

This is not an important issue at current energy use levels.

Says who? When LA turned off lights at night for some occasion the temperature dropped.

 

[Loren Pechtel]

Saudi Arabia has large scale desalinization yet they are also buying water by the tanker. They have also attempted to tow icebergs.

Another question nobody has mentioned. It is al about greenhouse gasses.

Thermodynamically all consumed energy in the end shows up as heat. Being in a vacuum the only way to get rid of het is by radiation.

Asa rough approximation from dq = m*c*dT where q is total electric power and gasoline power consumed, m is heat capacity of air, m is mass of atmosphere what amount of energy is required to raise atmosphere 1 degree c. Assunibg nass of air much less than mass of the Erath.

This is not an important issue at current energy use levels.

Says who? When LA turned off lights at night for some occasion the temperature dropped.

The total power liberated by mankind is a drop in the bucket compared to what we catch from the sun.

 

[bilby]

Says who? When LA turned off lights at night for some occasion the temperature dropped.

The total power liberated by mankind is a drop in the bucket compared to what we our planet catches from the sun.

FTFY.

Unfortunately, it's a very big planet, and solar energy is therefore very diffuse even in the tropics. So while the planet gets a lot of energy, we don't.

The planet also has a nasty tendency to rotate, and to place clouds between the sun and the surface.

So while the total planetary insolation is vastly more than human energy use, it's sadly impractical to use it to power a hi-tech society. For that we need much greater energy densities than are available in sunshine.

 

[steve_bank]

In the vacuum we are in over time even with a relatively small increase in energy as heat, temperature will rise and continue to rise.

Put a sealed box in space filled with nitrogen. Dissipate 1 mill watt in the gas with say a simple resistor. If heat internal > radiated heat by the box temperature will rise towards infinity, until the resistor and power source melts.

 

[bilby]

In the vacuum we are in over time even with a relatively small increase in energy as heat, temperature will rise and continue to rise.

Put a sealed box in space filled with nitrogen. Dissipate 1 mill watt in the gas with say a simple resistor. If heat internal > radiated heat by the box temperature will rise towards infinity, until the resistor and power source melts.

What makes you think that this is a good model of the Earth?

Why do you assume that for the Earth, radiated heat is less than insolation plus internal heat generation?

The Earth was in approximate equilibrium between insolation/heat generation and radiative losses. Then we had an industrial revolution, and two things happened - we started to generate heat, and we changed the composition of the atmosphere - that change that equilibrium. The atmospheric changes are VASTLY more significant as a source of warming. This is not difficult to demonstrate, and indeed the IPCC, NASA, and others have done just that.

You can do the math yourself if you doubt theirs.

But until you have done so, you are in no position to assert confidently that the mere generation of heat by human activity is sufficient to be a concern in the absence of greenhouse gas emissions.

And once you do so, you will discover that at current levels of heat production, it is not.

 

[steve_bank]

Says who? When LA turned off lights at night for some occasion the temperature dropped.

The total power liberated by mankind is a drop in the bucket compared to what we catch from the sun.

Well I'll have to take a look at that.

 

[bilby]

Says who? When LA turned off lights at night for some occasion the temperature dropped.

The total power liberated by mankind is a drop in the bucket compared to what we catch from the sun.

Well I'll have to take a look at that.

That would be an excellent idea.

Total solar irradiance incident on the Earth is about 1.7x10¹⁷W

Total energy currently used by humans worldwide is about 1.5x10¹³W - four orders of magnitude less.

About 30-35TW of heat arrives at the Earth's surface from the core in the form of primordial heat (the heat due to the collapse of the materials from which the Earth formed). About half of this comes from the core, and half from the mantle.

Radioactive decay in the Earth's interior accounts for about another 12 Terrawatts - a similar order of magnitude to that from human activity.

So humans contribute about one part in ten thousand of the energy the sun delivers - and that's in the post industrial age (obviously we previously added far less). Our contribution is about a fifth to a quarter of the geological heat at the Earth's surface (primordial plus radiological).

Energy from the sun is more than 99.99% of the amount the Earth needs to radiate into space to maintain equilibrium. Our industrial heat is a drop in the bucket. At around 0.002% of the total (the other 0.008% being geological).

The insulating effect of Greenhouse Gas Emissions operates on a very large fraction of this total (basically all of it except what immediately reflects into space, so in the ballpark of 70-80%), while even if we multiplied our energy used by ten, it would still only go from 0.002% to 0.02%.

 

[James Brown]

Bilby, are you saying that we could maintain our industrial and commercial output, but without emitting greenhouse gases, and our climate would not be affected?

 

[Jokodo]

Bilby, are you saying that we could maintain our industrial and commercial output, but without emitting greenhouse gases, and our climate would not be affected?

Do the math.

I suspect that the changes in surface albedo due to land use are actually going to be a bigger factor than the sheer heat released.

I have no idea which way that would go, though, so the overall effect could even be a (very slight) cooling.

 

[bilby]

Bilby, are you saying that we could maintain our industrial and commercial output, but without emitting greenhouse gases, and our climate would not be affected?

I don't know about 'unaffected', but according to the back of my envelope, the effect of our activities in such circumstances would be a minuscule fraction of the effects our current greenhouse gas emissions have.

Even if we had a population of ten billion, all using energy at the rate that Americans currently do, I wouldn't anticipate measurable warming of the planet in the absence of atmospheric pollution.

As Jokodo points out, the impact is likely to be swamped by other factors, such as changes in land use - cutting down dark forests and replacing them with lighter coloured crops may well have a sufficient cooling effect to completely swamp the warming effects due to mere energy consumption.