Let's face it, one day, possibly in some of our lifetimes we will run out of oil, perhaps not all oil, but cheap oil. When it runs out what will we do? This is a common question, especially when we'll reach 9 billion people before the end of the century, combine this with more and more people on the planet becoming middle class and consuming insane amounts of energy.
Also, it's not just oil that we need to worry about abusing and using up, it's other dirty sources of energy such as coal and natural gas. Fossil fuels in general are dirty and the sooner that we can stop burning them the better.
So, what are our options? Solar, geothermal, wind, nuclear, and future technologies not yet invented or being researched heavily right now. These are all great technologies, but they all have flaws and limitations. So even if these alternative sources of energy replaced 100% of our use of fossil fuels we would still need oil. Let's explore this further...
Our addiction to oil
The human species is drunk on oil, it's been pretty much the sole source of power for all of modern history, and is found in pretty much everything.
We are so dependent on this stuff that to quit using it will be harder than a heroin addict trying to quit. Add to the mix that the world reached peak oil several years ago, and it's all downhill from here in terms of the amount of oil left, and you'll see that the world needs to make some radical shifts to alternative sources of energy.
Oil just isn't what we use for energy, it has so many more uses and is used in just about everything from tires to plastics to pesticides that are sprayed on our food crops. So even if 100% of our energy came from alternative sources, we still need oil for so many things.
It's dirty, but cheap, really really cheap. It's basically in the same category as oil, but only really used for electricity.
Coal is one of the biggest sources of electricity in the world, found and used in just about every country with a decent amount of land, it will be extremely hard to stop burning this substance in exchange for energy production.
This is what people think of most when they think of alternative energy, yes it's great, but it has it's downsides. It's expensive to manufacture the solar panels, and they're actually not that efficient as the moment. It also only works when it's sunny, so for 10+ hours of the day you're not creating any energy at all.
One method of non-stop energy is storing the energy that solar power produces in a medium. A common one is molten salt, in this method the solar energy would heat tanks of salt to such high temperatures that it becomes molten. The energy stored in these tanks can then be used for non stop 24 hour steam generation used to spin turbines for power generation.
Wind, just like solar is great, but also has it's downsides, such as only working when it's windy. However we are making some great strides with this technology, which can be seen in countries like The Netherlands where they have moved these wind powered monsters into the sea, where they can produce over double the amount of electricity with no landscape eyesores.
Tapping the energy deep in the ground isn't anything new, it's a vast amount of cheap/free energy, but only exists in a few places on the planet. This will definitely become more and more desirable energy source as it's pretty much free.
Geothermal isn't perfect however, releasing the energy also releases many greenhouse gases into the atmosphere that are trapped deep in the earth. And although the energy produced is free, there are many start-up costs involved in creating these geothermal power plants. But when compared to many other energy sources this is a very good one that we should be investing in.
This stuff is great, in theory. In reality, you would have to use almost all of the arable land in the United States to produce enough of it to power this energy hungry nation. In essence, it takes more energy to make ethanol than you get from burning it, which is just ridiculous.
It's true that Brazil has had much success in producing ethanol and using it in approximately 88% of their vehicles throughout the country. One huge advantage that Brazil has over countries such as the United States is the ability to grow sugar cane, which is much more efficient at turning into ethanol than using corn. There have been many negative impacts on the country however due to producing this fuel such as farmers growing less food and thus driving up food prices. There are also more rainforests and natural habitats being destroyed to create more arable land for growing crops for this fuel.
Still not the solution as not only does it take a lot of energy to make this, but it's crazy dangerous. If we turned into a hydrogen economy, everybody would be driving around hydrogen tanks on four wheels that can aren't too hard to blow up.
Also, even though there is a huge abundance of hydrogen on the planet it's not as though you can drill a hole in the earth's crust and suck it out. Hydrogen production in it's cleanest form would come from separating the oxygen and hydrogen molecules from water. This separation is extremely simple as all it requires is electricity, currently this electricity comes from burning fossil fuels or alternative energy sources like solar and wind that are pricey to set up, and not very efficient (as of yet). So it's not as though hydrogen is free, it does come with a price tag to produce.
So is the planet screwed?
No, we're not screwed, but there is no magical future technology or energy source that will save us. I feel that the only hope that mankind has is to use a combination of alternative energy sources combined with using more energy efficient vehicles, homes and appliances.
We waste so much energy everyday running devices powered by electricity that only need to be run a fraction of the time. Not to mention how much energy we waste shipping good and food around the world that can easily be grown locally.
The human species is extremely adaptable and history has shown that we can change when we need to, no matter how stuborn we are. Combine this with the massive advances in technology that we have made over the last 200 years and I'm very optimistic that we will be okay in the future.