Timtom77 said:
-Do you think we will run out of fossil fuels?
Yes, for a very simple reason: Fossil fuels are finite vs. an exponential growth of energy requirements. Even if opinions differ on just how much oil there is left, how much coal and gas is left, etc... there is one thing we do know is a fact: the supply is limited.
The problem everyone fights about ofc is "when?", however both sides of the discussion have proven they can't count. Here's two hallmark numbers you need to remember when talking about exponential growth of anything:
a 7% (per annum) growth rate means doubling in 10 years,
a 3.5% growth rate means doubling in 20 years.
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Given our economies (and energy consumption) are supposed to grow (growth is good, right), and that outside of economic crisis the growth numbers generally land in the 3-7% range depending on which country you look at, that has a dramatic influence on reserves of any limited fuel.
For the sake of the argument, i'll take the 10 year doubling 7% growch rate, but the reality doesn't change much even if you assume a 15 or 20 year cycle:
If say we have a 100 year reserve of fuel X, that sound well and good, but
- 10 years down the road, the consumption doubled, bringing the reserve down to 50 years, 10 of which have already passed
- 20 years later, that 100y reserve equivalent to a 25y reserve, and 20 of those have passed....
And oops, we're about to run out.
Even if we take a 200 year supply, the actualy supply is still really short:
- 10y down the road, it's a 100y supply (10 of which have passed),
- 20y down the road it's 50y (20 of which have passed),
- 30y down it's a 25y supply
And ooops, we're out a while ago -- that's right, with double the initial reserve, we get about one more cycle, and not even that.
A 1000 year supply (estimated Thorium supply for Thorium breeder reactors)?
0:1000; 10:500; 20:250; 30:125; 40:62.5; 50:31.25
-- and ooops our 1000 year supply lasted less than 50 years.
Now, there are discussions about when peak oil has been reached, and if it has been at all. In the US, it certainly has, sometimes in the early 70ies, since then oil retrieval in the US is on the decline, which gets compensated with imports; worldwide there are differing opinions, but if the actual oil production stats are an indicator, we'we reached world-wide peak oil already - from now on, less and less oil can be pulled out of the ground, and that includes oil production of predicted discoveries of oil fields that have not yet been made.
The reality of that curve has one more implication: if peak oil has indeed been reached, that means half the oil that exists world wide (including undiscovered reserves) has already been used. According to our exponential function above, that would mean we have one more cycle before oil runs out.
There's caveats to that statement ofc: oil is not the only form of energy we use, things that run on oil get more efficient, and we might hit a bump-up on the road down if we're lucky. Also, the 7% growth numbers is a high estimate given the current economic crisis (worldwide GDP growth 2007-2010: 5.2%, 3.1%, -0.7%, 4.9%).
However the problem of the exponential function vs. a limited fuel supply is fundamentally true, for oil, for gas, for coal, for uranium. You can delay, and dodge a bit, but you can't change it. Mining a limited resource faster (Drill, baby, drill!) is obviously not a solution to the problem - it's a concept known as "strength through exhaustion" and complete idiocy to anyone who can count.
We might supplement fossil fuels by fermented "fossil" fuels, ie. ol produced by genetically engineered organisms, however there's alsso a slight problem with that: you need to feed those organisms, and agriculture needs energy (in fact, agriculture may well be defined as the industrial process by which energy is changed into food). Sooner or later, thermodynamics will give us the middle finger on that one - again, it can delay & help, but it's not a solution.
-Do you think Global Warming is a problem/exists/is caused by us?
Yes, although i believe the warming is less of a problem than the pollution or the above mentioned problem of exponential growth vs. a limited supply.
-Do you think we need to change from a fossil fuel based society? Why?
Because otherwise the exponential function will have surprise buttsex with our economies.
A combination of solar, hydro, wind and fusion to replace fossil fuels; with renewable resources heavily subsidized to accelerate the transition, as well as infrastructure changes that allow limited local producers of electricity (say solar panels on my roof) to feed electricity into the network.
What would also help would be cost-transparency. Every now and then we get a bunch of hippies running around demonstrating against nuclear fission; the reality is that right now we don't have much short-term alternative. The reality of fossil burnable fuels is pollution (which causes all sorts of respiratory diseases which don't get factored into the energy cost), and he reality of fission is that - while normally safe and clean - we have no final storage concept for nuclear waste, and accidents that do happen have unforseeable consequences (&costs).
There are ofc no perfect solutions: Hydro causes massive changes in the environment through construction; solar panels construction involves pollution & heavy metals while most of the countries who can currently afford them are in the location where solar panels are least effective, wind-power is ugly & noise, and fusion - while awesomesauce, and the tokamak reactors being failsafe, is still quite a ways off.