YOU: Fix the US Energy Crisis

[mheslep]

from a 2014 thread
View attachment 87131

I recall reading that bit from Asimov back in the day. Problem is, the one billion people of the 18th and 19th centuries demolished forests in the Americas and Europe, obliterated fisheries, nearly exterminated the bison and wolves and some whale species, and regularly had famines among the human population. Now, with ~seven billion humans, not so much.

 

[mfb]

Well, it is hard to exterminate species that are extinct already, and killing the last groups is not commercially reasonable in most cases. We are exterminating species at a rate higher than ever before. Famines became rarer, especially in industrialized countries, right.

 

[jim hardy]

I recall reading that bit from Asimov back in the day. Problem is, the one billion people of the 18th and 19th centuries demolished forests in the Americas and Europe, obliterated fisheries, nearly exterminated the bison and wolves and some whale species, and regularly had famines among the human population. Now, with ~seven billion humans, not so much.

Well, as OM said

If all we did was solve how to feed ourselves, we'd be little more than cats.

but we still haven't figured out how to manage our litterbox.

 

[mheslep]

Well, it is hard to exterminate species that are extinct already, and killing the last groups is not commercially reasonable in most cases. We are exterminating species at a rate higher than ever before. Famines became rarer, especially in industrialized countries, right.

If I understand correctly, most of the species destruction today is from invasive species, not from out of control hunting and harvesting of the 19th century kind. That is, shrinking the human population back to one billion would not solve that problem.

 

[OmCheeto]

If I understand correctly, most of the species destruction today is from invasive species, not from out of control hunting and harvesting. That is, shrinking the human population back to one billion would not solve the problem.

That depends on which problem you are talking about.
When I was born, the town I grew up in had a population of 4000. It is currently populated by 110,000 people.
Driving through the area now, it's pretty amazing how the farms I once worked at, were sold off to massive housing developments.

I think a billion people would be much more manageable.
I calculated one day, if the state I live in, could survive with a sustainable harvest of timber, as a source of electrical energy.
We can't.

From the thread: Can a bio-fuel based energy be future houses? Post #19
...
29,201,748,097,500 watt hours of sustainable Oregon forest(annual)
46,800,000,000,000 Goonie* watt hours/yr consumption(based on my electrical usage and number of fellow Goonies)
...

So if the population Goonieland were to be cut to a seventh, the numbers look sustainable:

29 trillion watt hours of sustainable Oregon forest(annual)
6.7 trillion watt hours/yr consumption (based on my electrical usage and number of fellow Goonies)​

And since a sustainable harvest of trees is carbon neutral, it makes more sense to me, than a non-carbon neutral source.

I recall reading that bit from Asimov back in the day. Problem is, the one billion people of the 18th and 19th centuries demolished forests in the Americas and Europe,

Perhaps then, a billion is still too many.

obliterated fisheries,

From the sources I've seen, most of this happened in the last 40 years. Do you have any examples from the 18th & 19th centuries?
I can't imagine they were a fraction as efficient as we are today, at harvesting fish.

400 tons‽ of jack mackerel caught by a Chilean purse seiner[wiki-n-me]​

nearly exterminated the bison and wolves and some whale species, and regularly had famines among the human population.

Perhaps bison, wolves, and whales were once as plentiful as people, and without the internet, no one knew that slaughtering them was a problem.

Now, with ~seven billion humans, not so much.

I've been labeling myself as a techno-greenie for about 20 years, and I think it's very nice that technology can feed this many people.

hmmm... It strikes me that we've strayed a bit from Russ's original rule; "Provide a solution".
Pointing out a white elephant in the room, is not really a solution.
And "shoulda woulda coulda" doesn't really solve anything.

Perhaps @rootone should start a new thread. I'm sure it would generate quite a lively, and most interesting discussion.

------------
ok to delete. my thoughts on the matter, are saved

 

[mfb]

Oregon has a population of 15 per square kilometer, or 30 per square kilometer of forest.
The world average is 50 per square kilometer, or 180 per square kilometer of forest.

Take the bad efficiency of burning wood -> electricity into account and you need a much smaller population to live based on that. Oh, and electricity is just a small fraction of the total energy demand.

 

[mheslep]

Do you have any examples from the 18th & 19th centuries?

Whaling of course,

"Yankee whalers" from the new American colonies replaced the Basques. Setting out from Nantucket, Massachusetts and Long Island, New York, they took up to 100 animals in good years. By 1750, the commercial hunt of the North Atlantic right whale was basically over.

and then http://www.oysterva.com/oyster-history.html :

Biologists have estimated that when the English settlers reached Virginia and Maryland in the 1600s, oysters were filtering the entire Chesapeake Bay once a week. The result was waters of remarkable clarity, even down to depths of twenty feet or more.
...
By 1875 a total of 17 million bushels was removed from the Chesapeake, yet harvesting continued to increase. At its peak in the mid-1880s, over http://www.oysterva.com/oyster-consumption.html
...
In the http://www.oysterva.com/oyster-landings.html began to decline. Many oyster beds were destroyed and reefs had been mined away. By the 1920s, the boom was over

Today oyster harvests in the Chesapeak Bay do not exist as a large commercial enterprise (though recently a comeback may be occurring).

None of this is meant to ignore the over fishing in the oceans via today's factory ships, but I see this as different thing from the wholesale obliteration that occurred in the 18th-19th centuries,

 

[OmCheeto]

Oregon has a population of 15 per square kilometer, or 30 per square kilometer of forest.
The world average is 50 per square kilometer, or 180 per square kilometer of forest.

Take the bad efficiency of burning wood -> electricity into account and you need a much smaller population to live based on that. Oh, and electricity is just a small fraction of the total energy demand.

I was going to mention that, but I was distracted by my continued psychological analysis of my new bff.
He reminds me a bit of humanity:
Incredibly stupid life choices, leaving him in a bit of a bind, but interested in learning.

Yesterday and today, we discussed how solar powered LED lawn lights work.

 

[mheslep]

And since a sustainable harvest of trees is carbon neutral, it makes more sense to me, than a non-carbon neutral source.

I suspect that would have the same effect as before, circa 1850, i.e. mowing down all the forests. No thanks. And wood combustion has far more traditional pollutants (CO, NOx, particulates, SOx) per unit energy (figure 2) than natural gas, even more than coal (except for sulfur compounds).

Some Europeans however are boldly returning to 1850 and ramping up biofuels. Germany now burns up half its annual timber harvest and biomass is now single largest source of renewable energy there (53 TWh/yr), larger than German wind (47 TWh/yr), biomass having tripled in the last 10-15 years. Unfortunately, the US and Canada are happy to mow down their own forests and supply Europeans with wood when they run short, having doubled exports of wood pellets in each of the last couple years.

 

[OmCheeto]

Whaling,

Your comment seems a bit selective.

"Yankee whalers" from the new American colonies replaced the Basques. Setting out from Nantucket, Massachusetts andLong Island, New York, they took up to 100 animals in good years. By 1750, the commercial hunt of the North Atlantic right whale was basically over.

... fast forward ...

The beginning of the 20th century saw much greater industrialization of whaling, and the harvest grew rapidly. By 1937, there had been, according to whalers' records, 38,000 takes in the South Atlantic, 39,000 in the South Pacific, 1,300 in the Indian Ocean, and 15,000 in the North Pacific. The incompleteness of these records means the actual take was somewhat higher.

100 per year <1750
38000+39000+1300+15000 = 93,000 in 1937

I really wouldn't mind the sustenance harvesting of whales by people in sailing, and row boats.

and then http://www.oysterva.com/oyster-history.html :

Today oyster harvests in the Chesapeak Bay do not exist any more as a large commercial enterprise.

None of this is meant to ignore the over fishing in the oceans via today's factory ships, but I see this as different thing from the wholesale obliteration that occurred in the 18th-19th century.

Wholesale obliterations, in the olden days, seem to have been confined to bays, and rowable/sailable distances.*

I think it's time to learn from the past, and move on.

---------------------
*To all you smarty pantsers... We're discussing non-human creatures here. No need to bring up the last 6000 years of humanity vs humanity slaughters.

 

[Buckleymanor]

Well one way to fix the energy crisis in the US and everywhere else would be to reduce the number of people.
Apparently that idea isn't very popular though.

Yes reducing the number of people won't be the most popular idea but how about encouraging people to be smaller.
Same effect but no one has to be denied a life or die.

 

[Shadow-Shocker]

There is one problem I see that is a bit of a big factor to consider when solving for energy, money. First off, people in the industrial revolution invested a lot of money in the face of oil, so much so that the government started to invest money into sovereign wealth funds (SWF), which are investments for big governments towards excess reserves. The United States (US) alone from SWF investing in foreign oil cash their investment in the hundred-billion-dollar range. This may be good for the US, but this action is damaging the planet. Since more oil=fossil fuel burning=thinning of the ozone layer=higher temperatures=more green house gases=global warming=Artic poles melting=flooding of countries=ruining economies=harming civilization=chaos etc. Plus, this type of investing in oil leads to war with other countries since it impedes countries on their rights, (Ex: The wars in the middle east). What I believe we should do is to move the investments towards electricity, try to recover more works from Nikola Tesla, reconstruct the Wardenclyffe tower, and find a way to make this type of electricity profitable so we can maximize the best we can on economies. Easier typed than done.

 

[jim hardy]

I say "Global Warming ? Just in the nick of time. We were due another ice age."

 

[JM samuel Liu]

Well after reading most of the replies, I have two points to make.

The first is that people seems to overlook what wave energy is able to do. The main problem of wave energy is that we are not able to harness it. The amount of energy out there in the ocean is humongous and will be able to solve whatever energy crisis no problem. In comparison to tidal, wave energy technology can obviously produce more and wave farms can also be deployed at many more locations (offshore for maximum power extraction) around the world than tidal technology.

The second is that we are simply not going to run out of fossil fuels and the CO2 emission is what's causing the panic. Investments into technology which deals with the increasing level of CO2 can be a easier and more painless option than transforming the whole of US into sustainable energy. Apparently researchers are trying to create compounds which can absorb CO2 in the air. As long as we are fixing the Earth's atmosphere at the same rate as we are damaging it, we will be fine for a bit.

 

[mheslep]

Wave energy is not as abundant as you might think. http://www1.eere.energy.gov/water/pdfs/mappingandassessment.pdf of wave energy available off the US lower 48 coasts, or 104 GW average, against the US installed shore capacity of over 1000 GW, for electricity alone. At the moment, there are no large scale (>10 MW) wave power installations operating anywhere in the world. The few wave demonstration projects total less than 3 MW, or the size of single large locomotive engine. And wave power suffers to a degree the same major problem as solar and wind, intermittentcy.

 

[AJacq]

Apologies if I lack correct terminology...

Oil, gas and coal have a very high energy density which I believe is why our society has been able to grow so rapidly (not to mention the innumerable derivative products we get from fossil fuels)... from what I understand from physics, nothing can ever be gained nor lost, it is just transformed... with this in mind, millions of years of stored solar power and chemical reactions which sedimented, and transformed with pressure, heat and a lot of time turned into oil and gas... how can a society built on the use of this type high density energy be expected to switch to very low density "real-time" energy ?

Renewable energy such as solar, wind, wave, etc. are not on demand sources : we can only get what nature provides at a given time, at a given place. Whereas oil, gas and coal can be moved, stockpiled and used readily to satisfy demand... so we would need to install a LOT of extra capacity, converting electrical power into chemical power and storing it. e.g build massive solar and wind farms that produce hydrogen that can be stored and used on demand by converting it back to electricity... but from what I understand, every time energy is converted from one form to another we "loose" some of it through inevitable inefficiencies... which leads us to building even more extra capacity.

Solar panels, wind turbines, etc., all these systems require energy to be built, deployed and maintained... considering my 2 previous points about low energy density and extra capacity, we would be using a lot energy to make a little energy... would this work in the long run ?

The promise of fusion energy in the future is nice but right now I only see 1 viable option : nuclear fission... it has a lot negative aspects to it but if we want to maintain our lifestyle which fuels (pun intended) the current trend for global energy demand and economic growth, I see no other alternative.

 

[jim hardy]

how can a society built on the use of this type high density energy be expected to switch to very low density "real-time" energy ?

Gonna be a period of adjustment...
People will adjust to a smart grid saying what smart appliances can run when.

 

[AJacq]

Gonna be a period of adjustment...
People will adjust to a smart grid saying what smart appliances can run when.

That seems like a big change in habits and mindset for a society used to having it all, right away, all the time.

But what about something like air travel without fossil fuels ?

The only solar airplane I know of carries only 1 at 43 mph with a wingspan of 208 ft... a Boeing 787 carries 300+ at 560 mph with a wingspan of 197 ft...

Solar airplane per passenger : 4410 pounds to travel 1566 miles in 36 hours
Fossil airplane per passenger : 1856 pounds to travel 8790 miles in 15 hours

More than twice the weight for 1/5 distance at 1/13 speed

...that's a big adjustment

 

[johnbbahm]

Apologies if I lack correct terminology...

Oil, gas and coal have a very high energy density which I believe is why our society has been able to grow so rapidly (not to mention the innumerable derivative products we get from fossil fuels)... from what I understand from physics, nothing can ever be gained nor lost, it is just transformed... with this in mind, millions of years of stored solar power and chemical reactions which sedimented, and transformed with pressure, heat and a lot of time turned into oil and gas... how can a society built on the use of this type high density energy be expected to switch to very low density "real-time" energy ?

Renewable energy such as solar, wind, wave, etc. are not on demand sources : we can only get what nature provides at a given time, at a given place. Whereas oil, gas and coal can be moved, stockpiled and used readily to satisfy demand... so we would need to install a LOT of extra capacity, converting electrical power into chemical power and storing it. e.g build massive solar and wind farms that produce hydrogen that can be stored and used on demand by converting it back to electricity... but from what I understand, every time energy is converted from one form to another we "loose" some of it through inevitable inefficiencies... which leads us to building even more extra capacity.

Solar panels, wind turbines, etc., all these systems require energy to be built, deployed and maintained... considering my 2 previous points about low energy density and extra capacity, we would be using a lot energy to make a little energy... would this work in the long run ?

The promise of fusion energy in the future is nice but right now I only see 1 viable option : nuclear fission... it has a lot negative aspects to it but if we want to maintain our lifestyle which fuels (pun intended) the current trend for global energy demand and economic growth, I see no other alternative.

It is not all bad news, we can store and accumulate the low density irregular energy from alternative sources
as man made hydrocarbon fuels, We loose some energy in the storage process, but the resulting fuels are identical
to the ones made from fossil oil, except the carbon comes from the atmosphere.
http://jalopnik.com/5948969/this-e-fuel-works-just-like-gasoline-but-is-entirely-carbon-neutral

 

[AJacq]

It is not all bad news, we can store and accumulate the low density irregular energy from alternative sources
as man made hydrocarbon fuels, We loose some energy in the storage process, but the resulting fuels are identical
to the ones made from fossil oil, except the carbon comes from the atmosphere.
http://jalopnik.com/5948969/this-e-fuel-works-just-like-gasoline-but-is-entirely-carbon-neutral

The idea is intriguing but I am skeptical (just as the author of the article) :

- Gasoline is about 1000 denser in energy than methane : so for every litre of gasoline we want to replace we need to produce 1000 litres of e-gas.

- How much renewable energy is required to produce e-gas energy ? To illustrate my point, let's take a totally hypothetical 2:1 ratio for example purposes... every time we want one extra unit of e-gas we have to built infrastructures that produce 2 units of energy from renewable sources... but renewable sources have variable outputs so extra capacity is required to insure constant production of e-gas, so we get a 3:1 ratio to account for variability... but those infrastructures require energy for fabrication, deployment and maintenance, so we get a 4:1 ratio... in the end would we be using 4 units of energy to make 1 unit energy... I'm not sure that can be sustained long-term, on a global scale.

... and I also may be way off in my reasoning (I'm not a scientist) !

 

[Buckleymanor]

The idea is intriguing but I am skeptical (just as the author of the article) :

- Gasoline is about 1000 denser in energy than methane : so for every litre of gasoline we want to replace we need to produce 1000 litres of e-gas.

- How much renewable energy is required to produce e-gas energy ? To illustrate my point, let's take a totally hypothetical 2:1 ratio for example purposes... every time we want one extra unit of e-gas we have to built infrastructures that produce 2 units of energy from renewable sources... but renewable sources have variable outputs so extra capacity is required to insure constant production of e-gas, so we get a 3:1 ratio to account for variability... but those infrastructures require energy for fabrication, deployment and maintenance, so we get a 4:1 ratio... in the end would we be using 4 units of energy to make 1 unit energy... I'm not sure that can be sustained long-term, on a global scale.

... and I also may be way off in my reasoning (I'm not a scientist) !

Gasoline might be 1000 denser in energy than methane but that is only it's energy density by volume.To get a more precise picture of a substances energy content you have to take into account it's net calorific value by mass. When you look at that, the difference between gasoline and methane is not much.

 

[johnbbahm]

The idea is intriguing but I am skeptical (just as the author of the article) :

- Gasoline is about 1000 denser in energy than methane : so for every litre of gasoline we want to replace we need to produce 1000 litres of e-gas.

- How much renewable energy is required to produce e-gas energy ? To illustrate my point, let's take a totally hypothetical 2:1 ratio for example purposes... every time we want one extra unit of e-gas we have to built infrastructures that produce 2 units of energy from renewable sources... but renewable sources have variable outputs so extra capacity is required to insure constant production of e-gas, so we get a 3:1 ratio to account for variability... but those infrastructures require energy for fabrication, deployment and maintenance, so we get a 4:1 ratio... in the end would we be using 4 units of energy to make 1 unit energy... I'm not sure that can be sustained long-term, on a global scale.

... and I also may be way off in my reasoning (I'm not a scientist) !

From what I have read the process is now about 70% efficient, which means it would take 55 Kwh
to make a gallon of gasoline, and about 58 Kwh for a gallon of diesel fuel.
Someone went to the trouble to figure out how many acres of solar panels it would take to generate
1 Gwh per year (2.8 acres).
http://www.energymanagertoday.com/i...wh-of-solar-energy-per-year-says-nrel-094185/
Based on that, the 2.8 acres would generate enough energy to create around 18,000 gallons of gasoline per year.
Countries like Iceland with geothermal resources, could become net fuel exporters.

 

[AJacq]

Gasoline might be 1000 denser in energy than methane but that is only it's energy density by volume.To get a more precise picture of a substances energy content you have to take into account it's net calorific value by mass. When you look at that, the difference between gasoline and methane is not much.

I agree : energy density (MJ/L) versus specific energy (MJ/kg)

Gasoline : 34 MJ/L and 46 MJ/kg
Methane : 0.0364 MJ/L and 55 MJ/kg

It's a force of habit because I tend to look at a situation in a business way... here is my reasoning : If I need to carry/transport 1000 MJ of energy, with gasoline I'm figuring 30 litres weighing 22 kg, with methane I'm figuring 28000 litres weighing 18 kg... but what about the size and weight of the container ? With gasoline two 5-gallon plastic buckets of negligible weight will do fine. With methane, I would need two 6K ultra high-pressure steel cylinders that are 60 inches tall, have a combined weight of 600 pounds and contain the methane at 6000 psi.

1000 MJ of gasoline : 30 litres and about 23 kg
1000 MJ of methane : 28000 litres and about 618 kg

How much energy will I have to expend to transport 1000 MJ of gasoline versus 1000 MJ of methane ?
How much energy will I have to expend to put (pour) 1000 MJ worth of gasoline in the 2 buckets versus to put (compress) 1000 MJ worth of methane in the 2 cylinders ?

 

[AJacq]

From what I have read the process is now about 70% efficient, which means it would take 55 Kwh
to make a gallon of gasoline, and about 58 Kwh for a gallon of diesel fuel.
Someone went to the trouble to figure out how many acres of solar panels it would take to generate
1 Gwh per year (2.8 acres).
http://www.energymanagertoday.com/i...wh-of-solar-energy-per-year-says-nrel-094185/
Based on that, the 2.8 acres would generate enough energy to create around 18,000 gallons of gasoline per year.
Countries like Iceland with geothermal resources, could become net fuel exporters.

Indeed !

The United States consumes about 140 billion gallons of gasoline per year... that's the equivalent of 35000 square miles of solar farm (48000 square miles with enclosed land)!... about 40% of Arizona covered in solar panels just to make gasoline.

 

[Buckleymanor]

I agree : energy density (MJ/L) versus specific energy (MJ/kg)

Gasoline : 34 MJ/L and 46 MJ/kg
Methane : 0.0364 MJ/L and 55 MJ/kg

It's a force of habit because I tend to look at a situation in a business way... here is my reasoning : If I need to carry/transport 1000 MJ of energy, with gasoline I'm figuring 30 litres weighing 22 kg, with methane I'm figuring 28000 litres weighing 18 kg... but what about the size and weight of the container ? With gasoline two 5-gallon plastic buckets of negligible weight will do fine. With methane, I would need two 6K ultra high-pressure steel cylinders that are 60 inches tall, have a combined weight of 600 pounds and contain the methane at 6000 psi.

1000 MJ of gasoline : 30 litres and about 23 kg
1000 MJ of methane : 28000 litres and about 618 kg

How much energy will I have to expend to transport 1000 MJ of gasoline versus 1000 MJ of methane ?
How much energy will I have to expend to put (pour) 1000 MJ worth of gasoline in the 2 buckets versus to put (compress) 1000 MJ worth of methane in the 2 cylinders ?

A cheaper method quite often used in industry to transport large amounts of gases is to pipe it.

 

[AJacq]

A cheaper method quite often used in industry to transport large amounts of gases is to pipe it.

Yes you're right of course... but gasoline is primarily used for cars... an average car has a 50-litre tank, so 38 kg of gasoline worth 1650 MJ... what would be the size and weight of the tank for a car that carries 1650 MJ worth of methane ? How much inefficiencies would this car sustain carrying about 1000 pounds of tank-weight.

... and how much energy would we expend to mine, transport, smelt, fabricate and install an extra 1000 pounds of high strength steel for each car... would would we still come out ahead energy wise ?

 

[johnbbahm]

Indeed !

The United States consumes about 140 billion gallons of gasoline per year... that's the equivalent of 35000 square miles of solar farm (48000 square miles with enclosed land)!... about 40% of Arizona covered in solar panels just to make gasoline.

Consider two things,
1: What are the other alternatives?
2: There is no requirement that the solar panels be in a contiguous space.
Personal transport, is not really the problem, but Ships, tractors, and jets.
Fuel economies will continue to increase, I drove a rental in Europe in 2009 that got
an honest 59 US MPG, and was fun to drive.
I think Toyota is already making a fuel cell hybrid
https://ssl.toyota.com/mirai/
As that technology improves, perhaps Mr. Carnot can finally retire.
I personally would like to see some improvements in steam reformation, to extract the hydrogen stream
from liquid hydrocarbon fuels, as storing hydrogen is still a big problem.
The point is the energy is there, just not in a high density usable form.
the ability to store and accumulate the energy in a liquid hydrocarbon format,
solves many of the problems with the alternative energy solutions.

 

[AJacq]

Consider two things,
1: What are the other alternatives?
2: There is no requirement that the solar panels be in a contiguous space.
Personal transport, is not really the problem, but Ships, tractors, and jets.
Fuel economies will continue to increase, I drove a rental in Europe in 2009 that got
an honest 59 US MPG, and was fun to drive.
I think Toyota is already making a fuel cell hybrid
https://ssl.toyota.com/mirai/
As that technology improves, perhaps Mr. Carnot can finally retire.
I personally would like to see some improvements in steam reformation, to extract the hydrogen stream
from liquid hydrocarbon fuels, as storing hydrogen is still a big problem.
The point is the energy is there, just not in a high density usable form.
the ability to store and accumulate the energy in a liquid hydrocarbon format,
solves many of the problems with the alternative energy solutions.

Just to be clear, I was not suggesting that a contiguous 48000 square mile solar farm be constructed... I was simply illustrating the size and scope of the solar energy requirements to replace gasoline... I used Arizona because of the abundant days of sunshine.

Unless I'm mistaken, I don't believe much gasoline is used to supply energy to dwellings, commercial buildings or industrial parks... in those cases it's electricity and natural gas... how much coal and fossil methane is used each year in the US alone ?

I believe personal transport is part of the problem... but I agree that ships, trains, trucks, airplanes are big contributors also... I don't see trucks running on methane, much less airplanes.

Our modern society evolved and prospered in great parts through the use of readily available abundant high density energy sources... yes other energy sources are available but as I see things now they are expensive energy-wise to implement for very little energy return : the energy input is greater than the energy output... How many solar panels would it take to generate enough energy to build a solar panel ?... from mining the raw materials through to maintaining it throughout it's life-cycle... AND how much would this additional newly-added solar panel be able to contribute energy-wise to build yet another solar panel ?

As for your questions about alternatives... I honestly don't know... If I think of something I'll post it.

 

[johnbbahm]

Just to be clear, I was not suggesting that a contiguous 48000 square mile solar farm be constructed... I was simply illustrating the size and scope of the solar energy requirements to replace gasoline... I used Arizona because of the abundant days of sunshine.

Unless I'm mistaken, I don't believe much gasoline is used to supply energy to dwellings, commercial buildings or industrial parks... in those cases it's electricity and natural gas... how much coal and fossil methane is used each year in the US alone ?

I believe personal transport is part of the problem... but I agree that ships, trains, trucks, airplanes are big contributors also... I don't see trucks running on methane, much less airplanes.

Our modern society evolved and prospered in great parts through the use of readily available abundant high density energy sources... yes other energy sources are available but as I see things now they are expensive energy-wise to implement for very little energy return : the energy input is greater than the energy output... How many solar panels would it take to generate enough energy to build a solar panel ?... from mining the raw materials through to maintaining it throughout it's life-cycle... AND how much would this additional newly-added solar panel be able to contribute energy-wise to build yet another solar panel ?

As for your questions about alternatives... I honestly don't know... If I think of something I'll post it.

First the man made hydrocarbon fuels most likely to be made would be the liquid variety, as our infrastructure,
and uses are already in place to handle gasoline, diesel, jet fuel, ect.
Will it take a lot of area, of course, but I expect some double dipping of home solar will be involved.
A home in the south with sufficient panels to run the AC in the summer, will have abundant surpluses for as much as
six months a year. The ability to store energy over a several year time frame, means fall and spring surplus
could be directed to fuel production. Northern homes could store the surplus from long summer days for winter heating.
If we ever get any where near 50% solar homes, the grid will need some sort of dump load, so the surplus does not
damage the grid. Hydrocarbon energy storage, would be a good choice to bleed off the excess power from the grid.

 

[jim hardy]

But what about something like air travel without fossil fuels ?

JP7 is about 43,000 mj/kg. Edit oops, strike those zeroes ( thanks Ajacq)

You seem to appreciate energy density.

Perhaps with today's satellite and radar weather airships will return.

I went to a wind energy conference last year.
One of the exhibits was promoting ammonia based energy
it'll flow through existing pipelines
it's a known chemistry
and this morning i learned of a green way to make it.
http://resourceinsights.blogspot.com/2014/02/is-ammonia-holy-grail-for-renewable.html

At this point it's just an idea to be aware of and watch.

i don't know anyting about its energy density