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that will match petroleum in versatility and energy density will be no easy matter. The main benefit of petroleum when compared to its potential competitors is that as a source of energy it has one heck of a big energy punch in a relativeley small volume/weight (i.e. very high energy density). As of right now there are no practical alternatives that can come close to competing with conventional petroleum in usefulness, ease of production, and all round versatility for mankind. And that's not even taking into account the other benefits we get from petroleum as a feedstock for a whole bunch of different products fundamental to our consumer society.
You appear to be willing to take it on faith that the guys in the white lab coats will pull an energy rabbit out of their hat in time to save our bacon. Well maybe they will and maybe I'll win the lottery next week as well, but it would be a mistake to base my future plans on it. In any case, The time for making such a discovery and getting the infrastructure in place for a seemless switch over appears to be quickly running out.
Broadly speaking, our situation is this: our society demands energy inputs on a scale, absolute and per capita, that can't possibly be maintained for more than a little while longer. Sustainable energy sources can only provide a small fraction of the energy we're used to getting from fossil fuels. As fossil fuel supplies dwindle, in other words, everybody will have to get used to living on a small fraction of the energy we've been using as a matter of course.
Of course this is an unpopular thing to say. Quite a few people nowadays are insisting that it's not true, that we can continue our present lavish, energy-wasting lifestyle indefinitely by switching from oil to some other energy source: hydrogen, biodiesel, abiotic oil, fusion power, "free energy" technology, and so on down the list of technological snake oil. Crippling issues of scale, and the massive technical problems involved in switching an oil-based civilization to some other fuel in time to make a difference, stand in the path of such projects, but those get little air time; if we want endless supplies of energy badly enough, the logic seems to be, the universe will give it to us. The problem is that the universe did give it to us - in the form of immense deposits of fossil fuels stored up over hundreds of millions of years of photosynthesis - and we wasted it. Now we're in the position of a lottery winner who's spent millions of dollars in a few short years and is running out of money. The odds of hitting another million-dollar jackpot are minute, and no amount of wishful thinking will enable us to keep up our current lifestyle by getting a job at the local hamburger joint.
www.hubbertpeak.com/whatToDo/DeindustrialAge.htm
Considering that Hydrogen is frequently touted as the fuel that will run our industrialized societies in the future lets take a look at some of the many problems associated with a switch to a hydrogen economy, not the least being that it currently takes more energy to derive the hydrogen, whether by electrolysis of water or by extracting it from natural gas (the preferred method) than we can get by burning the hydrogen or using it in a fuel cell to produce electricity. By the way the Energy Returned on Energy Invested in conventional Petroleum from a land based pre-peak oil well can range upwards of 30 to 1 while for oil produced from tar sands it's something like a measly 1.5 to 1.
The media was all aglow recently with Spencer Abraham's announcement that the U.S. now has a roadmap for making the transition to a hydrogen economy. Secretary of Energy Abraham announced the plan at the Global Forum on Personal Transportation held in Dearborn, Mich. In his presentation, he touted the line that hydrogen produced from renewable resources can provide unlimited energy with no impact on the environment. Secretary Abraham noted that the transition to hydrogen would be a long-term process, which will require the participation of both industry and government.
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The document is at least 80 percent public relations. While admitting that in all areas there are serious problems to be overcome before we will be able to make a transition to hydrogen fuel cells, nowhere does this document take a serious look at the obstacles. Instead, this paper paints a pretty picture of our hydrogen future and leaves the details to future research and investment. So let us look at a few of the difficulties of developing a hydrogen fuel cell economy.
First off, because hydrogen is the simplest element, it will leak from any container, no mater how strong and no matter how well insulated. For this reason, hydrogen in storage tanks will always evaporate, at a rate of at least 1.7 percent per day. Hydrogen is very reactive. When hydrogen gas comes into contact with metal surfaces it decomposes into hydrogen atoms, which are so very small that they can penetrate metal. This causes structural changes that make the metal brittle.
Perhaps the largest problem for hydrogen fuel cell transportation is the size of the fuel tanks. In gaseous form, a volume of 238,000 litres of hydrogen gas is necessary to replace the energy capacity of 20 gallons of gasoline.
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A third option is the use of powdered metals to store the hydrogen in the form of metal hydrides. In this case, the storage volume would be little more than the volume of the metals themselves. Moreover, stored in this form, hydrogen would be far less reactive. However, as you can imagine, the weight of the metals will make the storage tank very heavy.
www.culturechange.org/hydrogen.htm
More on the EROEI problem
When an energy source that has an EROEI ratio of 4:1 is replaced with another, alternative, energy source which has an EROEI ratio of 2:1, twice as much gross energy has to be produced in order to reap the same net quantity of resulting usable energy.
This can be worse than it looks. Consider that I inherited one barrel of oil, and the EROEI was 4:1. I could use my one barrel and end up with four barrels. Now consider that the EROEI was 2:1, and I still wanted four barrels. Well, I can use my one barrel to extract two barrels, then I have to use those two barrels to extract the four barrels that I want. Thus with an EROEI of 2:1, it has cost me three barrels to gain four; whereas with an EROEI of 4:1, it only cost me one barrel.
This means that when a society moves to using energy sources that have lower EROEIs, the actual amount of energy available to use (for manufacturing, transport, heating etc.) inevitably will diminish
www.abelard.org/briefings/energy-economics.asp#tarsands_table
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