How To Fix The World

I always wondered about the implications of free unlimited energy. Humankind as a whole would become much more powerful with all sort of potential implications. Basically, it would mean having more of everything. However, any energy changing hands means, by the second law of thermodynamics, waste heat. That is written in stone. There would be a limit for the maximum energy we can use before Earth temperature begins to increase, fixed by the capacity of Earth of dissipating heat into space. I wonder how close we are to such limit already..

Total solar irradiance of the earth by the sun is around 12*10^19 W (accounting for the average al. Total primary energy consumption is around 2*10^13 W. So there is still a factor of 6 million there. Very roughly, you would need a factor of 100 to get a 1 K increase of the temperature. So there is still a factor of 60000 until this scenario occurs. Mind, I don't think energy will ever be completely free. There is always going to be at least some maintenance cost, so there won't be that much incentive to completely waste generated energy.

I would be genuinely surprised if a multi-megawatt solar electric field produced a megawatt of waste heat. Pretty sure that's par for the course for any comparable nuclear plant. Thermodynamic cycles involving fluid-based heat transfer are just inherently hot in a way that light striking glass and semiconductor plates is not. Photons I believe do cause the atoms they strike to kick out some low-energy photons but these light rays would already do that when they strike the Earth anyways so the net heating added by solar electric production is negligible.

Technically, atoms by themselves are usually not really involved in this. Nevertheless, thermodynamics does ensure that high-energy photons tend to generate low-energy photons in the long run.

As @Timsup2nothin correctly pointed out, the net waste heat generation depends on what surface you put the solar panel over. Putting it over tarmac, will have very different results than putting it on desert. But let's make an estimation. Typically, a commercial solar module has an efficiency around 20%. So to generate 1 W of power, you need 5 W of sunlight. If we take use the average albedo of 0.3, 70% of that would have been absorbed anyway. However, for maximum efficiency, a solar panel has to be as black as possible. If we take 5% reflectivity (and I believe state-of-the-art solar panels are better than that), this means that 25% more of the sunlight is absorbed than would have been without the solar panel. 25% of 5 W are 1.25 W. This means, a solar panel put on an average surface is going to produce more waste heat than electric energy. So your multi-megawatt solar electric field is also going to produce multi-megawatt waste heat.

That said, power plants that convert thermal energy to heat (fossil fuels or nuclear) usually generate more waste heat per generated electric power than that.
 
Thermodynamics is often applied on a bunch bigger scope and scale of matter, energy, momentum, entropy, etc. that you're suggesting, in most calculations anywhere near accurate (as close as is even possible).
This isn't true. Thermodynamic effects are major factors in practically all aspects of modern life from how far you can go on a tank of gas to how fast your can charge your iPhone. Just because we don't normally acknowledge that this is happening doesn't mean it isn't a driving force in every day life.
 
It is used in aerospace but I was actually talking about more humdrum consumer and commercial electronics.
Well don't tell those starving children that their laptops and iphones have gold in them or they might dismantle them to extract the gold to buy rice ;)
 
Total solar irradiance of the earth by the sun is around 12*10^19 W (accounting for the average al. Total primary energy consumption is around 2*10^13 W. So there is still a factor of 6 million there. Very roughly, you would need a factor of 100 to get a 1 K increase of the temperature. So there is still a factor of 60000 until this scenario occurs. Mind, I don't think energy will ever be completely free. There is always going to be at least some maintenance cost, so there won't be that much incentive to completely waste generated energy.



Technically, atoms by themselves are usually not really involved in this. Nevertheless, thermodynamics does ensure that high-energy photons tend to generate low-energy photons in the long run.

As @Timsup2nothin correctly pointed out, the net waste heat generation depends on what surface you put the solar panel over. Putting it over tarmac, will have very different results than putting it on desert. But let's make an estimation. Typically, a commercial solar module has an efficiency around 20%. So to generate 1 W of power, you need 5 W of sunlight. If we take use the average albedo of 0.3, 70% of that would have been absorbed anyway. However, for maximum efficiency, a solar panel has to be as black as possible. If we take 5% reflectivity (and I believe state-of-the-art solar panels are better than that), this means that 25% more of the sunlight is absorbed than would have been without the solar panel. 25% of 5 W are 1.25 W. This means, a solar panel put on an average surface is going to produce more waste heat than electric energy. So your multi-megawatt solar electric field is also going to produce multi-megawatt waste heat.

That said, power plants that convert thermal energy to heat (fossil fuels or nuclear) usually generate more waste heat per generated electric power than that.

Bottom line, if every parking lot and street was under a solar panel shade we wouldn't need giant power plants in the desert anyway, and we'd be less inclined to run the grossly inefficient A/C in our cars too. Won't work in high rise urban settings, but could make suburbia almost worthwhile.
 
Fun fact. Fans of the gold standard think we should bribe poor regions to degrade their ecology so that we can mine a socially and industrially useful metal that we then lock in a box
 
Nearly everyone talks about reducing energy consumption. Cars get more mileage. Energy Star appliances. House insulation. Jevon's Paradox then kicks in.

Improving efficiency, yes. But what about actually reducing overall energy consumption by cutting consumption? Do people really need those vacations in Thailand to be happy? Just an example, there are numerous things that are consumed, and take energy to produce, that are only desired because there is a deliberate effort to make it so. How would a world without the "advertising industry" be like?
 
Improving efficiency, yes. But what about actually reducing overall energy consumption by cutting consumption?
It's a very hard (though currently necessary) thing to convince people of. Now, if there's sufficient improvement in efficiency, then one can actually increase net consumption while reducing consumption of the nonrenewable at the same time. But asking people to have a lower quality of life net year than this year is incredibly hard. If I knew how to do it, I would.
 
Sex, drugs, & violence.*

You know, the old standbys.

I suppose they could be convinced maybe to change their priorities so it isn't seen as a reduction in lifestyle, but that's really slow. Then again, everyone seemed to change from learning musical instruments to listening to compressed music files fairly rapidly... though that might be net negative on energy now that I think about it. The clarinet probably holds up than an ipod for better and for longer.

*The bad kinds.
 
Improving efficiency, yes. But what about actually reducing overall energy consumption by cutting consumption? Do people really need those vacations in Thailand to be happy? Just an example, there are numerous things that are consumed, and take energy to produce, that are only desired because there is a deliberate effort to make it so. How would a world without the "advertising industry" be like?

Do people really need anything then? Do we need mass televised sports or MRIs or 20m squared of living space per person? I mean we can be living in a human hive practically, but if you show people they can have more than that they will want more. Ain't no going back. All you can do is cut population growth in general, a new pandemic that some virologists are expecting within the decade that will hollow out our cities and raise the bargaining power of labour like the black death did.
 
Do people really need anything then? Do we need mass televised sports or MRIs or 20m squared of living space per person? I mean we can be living in a human hive practically, but if you show people they can have more than that they will want more. Ain't no going back. All you can do is cut population growth in general, a new pandemic that some virologists are expecting within the decade that will hollow out our cities and raise the bargaining power of labour like the black death did.


MRIs are pretty useful.

I just want that home farm @Farm Boy was talking about, and I want a robot to tend to it.
 
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