Peak oil would not be a concern if there was alternatives with high EROEI. Without high EROEI alternatives peak oil may mean peak energy. The energy available in the future depends on the EROEI profile of the remaining energy reserves. I certainly don't know what this profile looks like, but it makes sense that we have been using the high EROEI energy sources first. The EROEI will decline continuously till we hit the EROEI of sustainable energy sources. The ratio of available energy to total energy = 1-(1/EROEI).
10    90%
5    80%
3    67%
2    50%
1.7    41%
1.5    33%
1.3    23%
1.1    9%
At an EROEI of 2 you have to invest half of a year's energy to have the same available energy next year.
I also do not know what the EROEI of the sustainable energy sources are. This is one area where technology may be able to help out. If we can increase the EROEI of sustainable sources there is a brighter future. On the other hand the peaking of other resources could actually decrease the EROEI of sustainable sources. For example copper prices have doubled twice in the last 3 years. This is going to have a big impact on all electrical projects. I seem to remember reading that hybrids use twice the copper of regular vehicles.
Altough it is ok to try to harvest a little bit more energy from "renewable" sources, energy creation is prohibited by the laws of physics.  I will assume that you know this law, mostly because people writting in the OilDrum usually have more knowledge than average person.

What you call technology is made of the following :

  1. Invest time (and energy) to make a concept for harvesting energy
  2. Elaborate the means to build it
  3. Find and extract the needed ressource in order to built it (all ressources need to be extrated or salvaged from previous extraction)
  4. Transform and put in basic shape the founded ressources
  5. Transport the needed ressources to some kind of manufacturing system (be it a plant, a coop, a oneman operation, it needs to be manufactured)
  6. Do all the needed operation to build it.
  7. Transport and install the built device to the place of energy harvest location (be it wind, solar, oil, hydro, coal, biomass, etc)
  8. Use part of the harvested energy to make the device work.
  9. Convert that energy in a portable fashion.
  10. So on

You get the point, in no place can you make more energy than what is harvestable.  

I wonder if the EROEI of feeding an horse is better than producing any biomass fuel.  

Why would you keep using a car anyway?

Where would you go with it?

To your current unsustainable job? (that you will loose no matter how hard you will try)

Ask yourself what do you really want to do with an electric handmixer.  Do you want to save time cooking so you can still keep your work?

Right now, use all the tool you can, that's what I do.  I have a car and use it because I can and it is the way the system work.

When the system will cease to function, you will have to adapt and I predict a handmixer will be of relativly low help.

There is several orders of magnitude more solar energy falling on the earth's surface each day than we use as a species so far. Energy availability is not the issue. Capture and conversion to useful forms is the issue. Furthermore, while I know that some people here diss the space program, serious studies have been done about increasing the captured solar energy from earth orbiting power stations and beaming that energy back to the ground as low intensity microwaves. None of thid involves creating energy, just capturing it. So go figure - we already have more energy hitting the earth's surface than we use from fossil fuels. And we already have the know-how to even expand upon that to capture more solar energy in the near earth region.

So what's the problem? The problem we have is not in capturing available renewable energy. The problem we have is one of mindset, of psychology, and of deliberately choosing to begin going down a road towards a renewable sustainable lifestyle. This problem is not only about energy. It's also about the myth of endless growth (which must stop) and that includes the endless growth of human population.

Even at 6 billion people, we have the knowledge to make the world a sustainable place. It would be very very different from the culture in which we live today but it doesn't have to be medieval serfdom or mad max. We just have to choose to do it. The sad thing is that so far we have actively refused to deal with these issues, especially the myth of endless growth being sustainable.

We will NOT be able to fuel the cars of the people that will feed the people also using their car in order to build those space solar panel.

Maybe you havent understand that Oil is the energy subside of everything NASA scientist could come up with.

I'm certainly aware of our planet receiving more solar energy than what is used as fossil fuels.  The problem reside in getting it concentrated enough.  

Even if we could (for very not any good reason) power some kind of car, the problem would then reside in getting enough nat gas or coal to keep on manufacturing fertilizers.

The problem is NOT a supply problem, it's a DEMAND problem.  Until the system is working, you will be able to use your car.  Once the system break, you wont need your car.

Actually, the demand problem will be solved rather easily (at least in the USA). Most people won't be buying gasoline because they won't be able to afford it. A trip in the car will be an important journey done for a purpose, because it will be too expensive to waste on anything trivial. There is a giant gap opening in the USA between the haves (top 10%) and everybody else. Rising oil prices are going to put the nail in the coffin.
Using satellites to convert solar energy to microwaves has an extremely low EROEI. Its not that the technology is impossible, its just impractical. Remember 1/R^2 losses.
I wonder if the EROEI of feeding an horse is better than producing any biomass fuel.

Certainly not. I have about 3 acres of pasture around my house. This is not enough to feed a hores all the year round (I would have to buy hay for winter, or have another couple of acres of pasture to make my own).

I'm sure that if I planted rapeseed, I could get more miles as biodiesel than I would ever get out of a horse; I really ought to do the calculation. (bearing in mind that a certain proportion of that biodiesel would be consumed by the tractor required to plough it).

In answer to your question as to whether it would be better energetically to keep horses or use pasture, hay fields and acres planted in oats (power bar equivalent for horses), you might be interested in checking out the Land Institute's Sunshine Farm project.

visit http://www.landinstute.org/ and search for "Sunshine Farm."

My recollection of their early conclusions was that there are pluses and minuses to both approaches.  Under certain conditions, there may not be much difference between the two.  One advantage to horses is that they replicate themselves, and do not require factories, metals, etc. to do so.  

Considerations in choosing one over the other may include the proclivities of the farmer (some folks do better with animals than others), the type of land included in the farm (amount of land that may be useful only for pasture or hay) and the suitability of the land and climate for growing oil crops.

Thanks for that Barb...
I found the article :
the crop acreage requirements of horses is no greater than that for tractors operating on biodiesel. In our feasibility study, detailed calculations, based on numerous early bulletins from the United States Department of Agriculture and state agricultural experiment stations, show draft horses require no more cropland for feed than tractors do for biodiesel on a net energy basis, both roughly one-fourth of a farm's cropland.

Fair enough, and very encouraging in terms of the productivity of post-oil farming... but this is discussing farm traction, not transport, which was the original question.

Another quote from the article is pertinent to that aspect :

Tractors provide timeliness in field operations, but horses can be used when time is not critical.

Timeliness is important in transport. I live about 8 miles from the nearest market town. I could go there with a pony and trap to do my shopping, but it would take me all day. If I can go there with an ethanol-powered scooter, or some lightweight biodiesel car, for the same energy input in terms of agricultural surface, then I've gained several hours.

Sorry to have missed that transport issue.  

Here in the U.S., farmers frequently lived not more than 3 miles from some town, which is a distance than can be covered by horse and buggy in about an hour.  You still see a town, or the remnants of a town, every 6 miles.  That is truly the case in the area where I grew up.  In less populated areas, you would often find some sort of small general store, the 1900s equivalent of a convenience store, on a rural crossroads.  These stores also doubled as post offices.  In addition, many farm families did not go to town during the week, but only made the big trip on Saturdays or to sell livestock or crops.

Formerly, many towns in the Midwest, East and South were on or no more than 20 miles from a railroad, which made delivery of goods much less energy intensive.  If we here could rebuild some of these low-use or spurs even for light use, we would be in much better shape.  That would be hard to do, though, on a sixth to a third the amount of liquid transportation fuel.

For smaller holdings or market gardens there may be advantages to the Electric Tractor
Or this interesting How To Convert

The extra weight of batteries and low-end torque of electric motors are great features for a tractor. Electric motors don't waste any energy when you aren't moving and the torque is greatest when you first start moving, right when you need it the most.

And although 'timeliness' is a factor, tractor use is intermittant with the tractor frequently found sitting in the shed for long periods of time...

Future developments of Gantry Systems my also help ameliorate other problems - depending on the situation.

Whatever the case, the present range of Very Large
Tractors
may not have much of a future...

Other thoughts/comments?

I also do not know what the EROEI of the sustainable energy sources are.
You need to look at The Ergosphere FAQ more often!
We are on almost the exact same wavelength. I see you even got to the bio-butanol story before I did. I just wrote about it last week:

Bio-Butanol

You wrote about it six months earlier in that FAQ.

RR

You know, I'd forgotten about that...

Funny thing, almost 40% of today's hits at The Ergosphere have been from clicks on that one link.  I hope people found it worth their time to read!

Cool. Thanks for this RR! Any idea how good university research on this stuff is in places like China/India/Brazil? Might the biofuels revolution come from the Far East?