Renewable Energy Sources?
Offline These are sources that essentially cannot get depleted, at least while the Sun can still shine and the Earth's radioactive isotopes have not all decayed. But we need not worry about either running out for the next several billion years.
So what are the possibilities?
Geothermal uses the Earth's heat, which is generated by the decay of the Earth's radioactive isotopes, which include K40, Th232, U235, and U238. However, the Earth's internal temperature does not increase very fast with depth, with the main exceptions being volcanoes. So one has to use hot springs and the like, and these are not very widely distributed. An alternative to that involves esssentially creating one's own hot springs. Drill a long way down, then pump in some water to create some cracks. Drill into those cracks to recover the heated water, and continue with adding more water.
The other source, the Sun, can be tapped both directly and indirectly in a variety of ways; it must be pointed out that most of the ways have trouble as a result of how diluted sunlight is. Sunlight also has the problem of being easily blockable by clouds, especially in the sorts of areas where many people prefer to live, and by being blocked by the Earth for about half the time at every place on it.
A simple way of tapping solar energy is to put solar water heaters on one's roof.
One can get around the dilution by focusing sunlight with mirrors; one might even use the concentrated heat to run a tubine/generator setup with that to generate electricity.
An alternate approach is the solar tower or solar chimney approach -- a tall chimney surrounded by a tower skirt, big area covered with glass or transparent plastic that gets heated by the Sun. Air inside it will try to rise, and the skirt will direct the heated air into the chimney, where it can power some turbine/generators.
And one can also generate electricity directly with photovoltaic cells.
Less directly, the Sun's heat makes the Earth's air and water circulate, making winds, waves, and a temperature gradient in the ocean -- all of which can be utilized and sometimes have been.
Tidal power might seem associated with waves, but the tides' uitlimate power source is the gravity of the Sun and the Moon combined with the rotation of the Earth, and that source is also not likely to run out for several billion years.
Back to solar, i note that plants also capture solar energy; their chlorophyll and other photosynthetic pigments are inside antenna complexes that act like tiny photovoltaic cells. And one can then use the plant material as fuel: biomass. One can burn it, or else bake it or ferment it to produce more convenient fuels.
I note in passing that fossil fuels are largely fossilized biomass. But it is being consumed at something like a million times the rate at which it is foruming. And in some cases, it is even worse. Most of the Earth's coal deposits formed before the Triassic Period, about 200 million years ago, which is when termites evolved. They started eating the dead trees, keeping them from forming coal deposits. Their ancestors were early cockroach-like insects, and some present-day cockroaches like eating rotting wood.
Nuclear energy is based on another sort of fossil fuel: uranium and thorium, which are produced in the cores of massive stars as they collapse to become neutron stars, and perhaps also by binary neutron stars in their final stages of inspiral. And that fossil fuel was frozen into the Earth when it formed 4.5 billion years ago. Fusion relies on hydrogen, helium, and perhaps lithium isotopes, which are leftovers from the Big Bang. But hydrogen has the nice feature of being MUCH more common than uranium.
That overview being done, I concentrate on some practical issues.
First, many of these alternatives are best adapted for producing electricity. This is no real problem for stationary customers like homes and offices and factories and the like, but moble customers are another story entirely. It is rather difficult to get good energy densities in batteries, energy densities comparable to those of combustible fuels. Thus, electric cars have not been very feasible, and the most successful electric vehicles to date have been electric locomotives and railcars, which "cheat" by getting their electricity from extra rails or overhead cables. Electric trolleybuses get their electricity in the same way, from pairs of overhead cables. And electric ships or airplanes are much less feasible.
So while the drive-everywhere lifestyle may become less and less feasible over time, we may still be able to enjoy much of what electricity has made possible for us.
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Since then, I have discovered some evidence of an additional mechanism that produces fossil fuels. Oceanic Anoxic Events.
These are when all of the oceans below the surface become devoid of oxygen, suffocating everything below, and allowing the remains of organisms and such to become deposited in organics-rich sediments.
The causes of OAE's are obscure, but one interesting possibility mentioned is an increased abundance of carbon dioxide in the atmosphere. This can be the result of massive volcanic eruptions, and some large igneous provinces do correlate well in age with some OAE's.
So we are not only consuming oil over a million times faster than its geologically-averaged formation rate, we are consuming it at an even faster rate compared to its current rate of formation.
But the circumstances of its formation suggest a way to form more of it: to cause super Global Warming. But despite the trouble it would cause, it would still not form oil fast enough.
Often the argument is made that there isn't enough energy in renewables to produce enough power to meet our needs. This is, of course, hogwash because nobody has really tried yet. Like in WW2 when people would plant victory gardens whereever they could so too could a massive war industry scale effort to free ourselves from polluting fuel sources be done.
There are plenty of rooftops where solar panels could be attached. Currently there is a limit on the amount of silicon being produced. It's an abundant source and there are companies like Evergreen solar that produce panels with hardly any silicon. America has the manufacturing infrastructure and labor to produce solar panels in mass quantities.
Wind is a easy resource to collect and wind turbines are found in numerous sizes. The only limitations is people who don't like wind turbines obstructing their views of grass or hills; the NIMBY crowd.
Improving efficiency is the easiest way to cut down on demand but the only limitation is industry who doesn't want to improve (auto manufacturers who still insist people want 10mpg when gas is $3 a gallon) and politicians who have been bribed to avoid legislation improving efficiency.
There are techniques to extract oil and gas from trash. Companies like Global Resource Technologies can convert old tires or coal to oil and gas without carbon emissions. If there's one thing America has plenty of it's trash.
There are a host of new technologies available but there will is implementing them on a mass scale is what's lacking. Having already passed the Hubbert's peak some time ago you'd think our country would look for a solution rather than await the upcoming recession with feinged looks of surprise.
I wonder how many nuke plants it would take to wean the energy grid off fossil fuels? After that, how many more would it take to power electric cars assuming a mass switchover?
Morte alla tyrannus et dei
I have also heard of a way to make plastic based solar panels that can absorb a wider spectrum of light without the need of direct sunlight/facing the sun directly. Cheaper and better then the current ones we have.
Another problem is that the standard turbines can't be used in cities because of multi-directional winds (whipping around buildings and such). However they have a kind of turbine that is a helix shape that can use wind energy from any direction in any configuration anywhere.
Another thing that could help a lot is use of thermal mass. Earthships use this among other technology currently available to the general public. It creates stable temps without using any heating or cooling element. Nothing but the mass anyway which is only powered by the sun and properties of insulation.
The solution will be the use of a lot of technologies. Mainly because solar cells don't work at night and wind doesn't work when there isn't wind.
Battery technology is improving and with it being used in military, space travel, and business applications the money needed for the research is at hand.
H2 is probably another thing that will help with it being able to store more energy in a more compact space and weight then batteries. This idea has already been used with success in a house that uses solar panels to gather energy in which the extra is stored in hydrogen using electrolysis. The person who did this also has a hydrogen powered car which he can use to power his home if he needs to.
Also the car needs to be rethought to work electricity. It is inefficient as it is. It can be lighter while being just as strong and use insulation to improve the effectiveness of temp controls. With battery power the energy of breaking can be captured. The motors have to be inwheel motors (energy used directly to the motion of the wheel), if they are not you are wasting power for no good reason. The capturing of energy can be and has been done in this kind of system with ease.
Most of these systems can be implemented in current homes. They would be an investment but will save money in the long run, to make this work it has to make sense financially. Solar cells on the roof with a wind turbine could go a long way.
With water look up Earthships. England's Millennium Dome uses the water catch idea for toilets. In the earthships they use water in the house 3 times.
I suggest anyone interested in these kinds of technologies take a look at a mini-series called eco-tech. Thats how I heard about a lot of these things or at least gave me a direction to run in.
Yes, there are the thin solar cells which I think use plastic. I invested in Evergreen solar which uses a lot less silicon that other types of cells. The price is certainly going down.
There are turbines which look like a small jet engine which fit on the roof or there are also ones that look like small sails which are produced from Mariah power. It tends to be the large industrial farms that are limited since their size provides fewer options. They tend to be more cost effective though.
Sadly I invested and lost a bunch of money in hydrogen. The technology to cheaply and cleanly produce hydrogen isn't available yet. Hydrogen is produced through petrol sources and require a lot of energy. It can be produced from water and solar power but it's more time consuming. A car that is powered on hydrogen has less of a range than one powered on the same amount of fuel of gasoline. While the hydrogen is abundant the technology is still far off. So far electric cars are the best option.