Wednesday, November 6, 2019

Geothermal Energy is the Renewable Energy Answer


Renewable Energy Choices

The world runs on energy. 

Without a steady supply of ready-to-use energy, the world would fall apart very quickly. 

The progress humanity has achieved and the abundance and standard of living we’ve become used to is possible because of available energy. When we discovered fossil fuels and the many sorts of products that could be distilled from crude oil, we had found our cheap and abundant energy source which would power invention, innovation, and industrialization. 

Fossil fuels have been abundant and cheap and therefore have been factored into the use of anything whose priorities have been widespread adoption, mobility, and cost-efficiency. Most notably, fossil fuels are heavily used in the production of electricity and in powering transportation in the form of cars and trucks.

Fossil fuels have a major downside, though. They aren’t renewable. When we’ve used all there is, there won’t be anymore coming around. If one totally ignores or sets aside the entire issue of global warming/climate change and just focuses on the ability of an energy source to be renewed and therefore infinite, we still need to think about what sort of energy to replace fossil fuels with. It would be foolish to continue on with the status quo without forming some sort of long-term plan concerning our future energy needs.

There are quite a few renewable energy options to consider. Most of them have merit, and some are maybe not the best option as a total solution but are the best when considering a specific application.


Electricity


One option is to switch everything that is powered by fossil fuels to electricity. This applies heavily to the application of cars and trucks. If instead of powering those personal transportation solutions with gasoline and diesel, they were able to be run using electric motors fed by battery, then we would greatly reduce our need of fossil fuels. 

This would be a great thing for progress but does have some major limitations. 

Firstly, battery technology is not as advanced as would be ideal. Even the highest range electric vehicles have a significantly shorter range than standard gasoline or diesel-powered vehicles. Electric cars and trucks would be great for people who have a need to travel shorter distances, somewhere under 30 miles between charges. 

There have been major advancements in battery technology (at companies like Elon Musk’s Tesla) which have increased the range of electric vehicles, but many people would drag their feet in purchasing a fully electric vehicle because of the range issue. So, if the electric car were to find widespread consumer adoption, the range and battery issues would need to be resolved.

Secondly, switching from fossil fuels to electricity doesn’t really eliminate the use of fossil fuels, it just changes where the fossil fuels are being burned. Most electricity is produced in power plants that run on coal. When you charge your electric car at home between trips, you are storing in your car’s battery electricity which was produced with fossil fuels. While concentrating the combustion of fossil fuels to fewer central locations could help by allowing greater efficiency, it is still not a total solution.


Solar


Another option is solar energy. There are two major types of solar energy production. There are photovoltaic cells and there is thermal solar.

Photovoltaic cells produce electricity when they are exposed to sunlight because the photons excite the atoms in the cells and cause electrons to flow. How awesome?! It’s like a magic sheet that just makes electricity when you shine light on it. It seems like a satisfactory total solution. 

Photovoltaic cells would be a great option in many instances, but this technology has difficulties to overcome. The PV cells are difficult and expensive to produce, making them an unsavory upfront investment. The production of PV cells requires toxic materials which are difficult to obtain and are finite, so we won’t be able to make an unlimited number of PV cells.

The other form of solar is thermal solar. Thermal solar takes advantage of the heat the sun gives off. 

Thermal solar can be engineered in many configurations, but one option is to arrange a bunch of mirrors to concentrate the power of the sunlight across a large area into a small, central spot. The focus of all the heat energy would be oil or water in a sealed tube which would heat up, expand, and spin a generator’s turbine. As the expanded fluid moved the turbine it would cool down, contract, and be moved around through the piping back to the place where the mirrors would fill it with heat again. 

One other configuration of thermal solar, which doesn’t have electricity as a product, is to cover the roof of a house with tubes filled with fluid which would absorb the heat from the sun, then circulate that heated fluid throughout the house to heat the house. This would prevent the use of electricity or natural gas in heating the home.

Both of these solar energy designs suffer from the same weakness – they only work when the sun is out. They stop working if it is nighttime or if it is cloudy. If a system were totally reliant on solar energy, then there would be regular cycles of power outages. The surplus energy created while the sun is shining may be stored in batteries for use during periods of darkness, which could realistically overcome this objection. Even still, solar energy works well as a supplemental source, a piece of the puzzle, but it won’t work as the only source.


Wind


Wind energy is another possibility. Wind energy can be harvested using large windmills which have fans that catch the wind and spin a turbine which produces electricity. These large wind turbines can create a lot of energy, and so seem like a great option. 

However, wind turbines only work where there are usually strong winds. There are places where it just isn’t ever that windy, and so the wind turbines would produce next to nothing. And even where a typically windy site is found, the wind isn’t constant, so there are times when the turbines won’t spin. 

The windmills are sometimes protested by the people who live near them because they are seen as eyesores, giant ugly sticks. They are resisted because they can make constant scraping sounds as they spin. They are large, expensive, and difficult to construct. Because of their limitation, they also won’t work as a total solution. They would work well if placed in concentration in locations where there is ample wind and then that energy is distributed to as wide a space as possible.


Hydroelectric


Hydroelectric energy, mostly harnessed using dams, is power created using the flow of water. Turbines connected to wheels covered in paddles can be placed in a river and the flow of water would engage the paddles, spinning the wheel and turbine. This could produce some electricity. 

On a massive scale, and to improve efficiency, large hydroelectric dams are built, stopping up a natural river, and ensuring that every drop of water that passes through applies energy to turning turbines. The water is routed through large tunnels or pipes and once it has turned the turbine, it is let go into the river on the other side. The essence of this, of course, is the force of gravity which is always pulling water to a lower point. This provides a massive amount of electricity and is very constant and renewable. 

The major drawbacks to hydroelectric power are its ecological effects and its location limitations. The dams built to help harness the power of flowing water interfere with the natural movements and lifecycles of fish and other wildlife. And rivers which have a sufficient volume of water to create electricity are limited in number, and most have already been tapped as energy sources. They provide a lot of electricity, but there isn’t much room for growth.


Tidal or Wave


Tidal or wave power is energy collected from the motion of waves in the ocean. The waters of the ocean ebb and flow because of the gravitational pull of the moon. As the moon travels around the Earth, it attracts the bodies of water, and then when it moves far enough away, the water returns to its original position. This constant pull and release of the massive bodies of water hold lots of potential energy. 

Underwater turbines or articulating see-saw type contraptions are used at the coasts to harness the tidal energy. The movement of the water is used, acting on the contraptions, to spin turbines which create electricity. 

The problems with this technology are similar to that of hydroelectric dams: ecological harm and location limitation. The fish and plant life are affected by the presence of these generators. And the places where tidal energy would work the best are along the coasts where land meets ocean. There is a lot of coast available, but it wouldn’t do much good for landlocked nations or communities far from the ocean.


Alcohol and Biofuels


Alcohol and biofuels have been suggested as possible replacements for fossil fuels. These two products would work in most automotive engines with few alterations. So, in terms of adoptability, they would be pretty easy. 

Alcohol is made by fermenting things that contain sugar to create a first-round alcoholic liquid, and then distilling that until you have concentrated, flammable alcohol.

Biomass is similar, but requires any plant material that contains fiber (most plans recommend wood, grass, or corn fodder because of the abundance of the material and the fiber content) and that material is either fermented into a diesel-like product that has a high octane rating and so explodes under great pressure, or the material is simply burned to produce heat.

Both alcohol and biomass can be used in automotive applications or in electricity-generating power plants. These options are great because they are able to be produced anywhere and at almost any scale because plant material and sugar occur everywhere on the planet and fermentation, distillation, and combustion can happen anywhere. 

These products are very mobile, allowing them to power moving vehicles. The products are carbon-neutral, or nearly that, because the material being burned has spent its whole life consuming and trapping carbon from the atmosphere.

There aren’t as many detractor points for alcohol and biomass as there are for some other alternative energy sources. One might be that the process for creating these products is very active, requiring constant collection of material and the never-ending processing of that material. 

While all the material used can be scrap from other processes, making use of what would have otherwise been waste, it would probably be more efficient to grow whole crops intended for these sorts of fuel production. This use of crop land might take away from food crops and might cause a shortage of food or an increase in food prices. Overall, I think this is a very viable solution for many of our energy needs.

There are likely more alternative energy possibilities available, but I don’t know much about them, and they might be so niche that they aren’t worth discussing here. My main purpose in talking about the alternatives I have is to essentially say that they aren’t going to work as a total energy solution, all building to my final alternative, which I believe will work as a total energy solution.


Geothermal


Geothermal energy is the best sort of renewable energy possible. 

The Earth is in constant motion, always rotating very fast, and the inner core, outer core, and mantle layers of the Earth move past each other causing friction. All of this friction caused by a huge amount of matter moving quickly and ceaselessly creates a tremendous amount of heat. The heat at the center of the Earth is so hot as to keep metal in a liquid state! This heat is always present, constantly being produced and renewed, and expected to be around as long as the Earth is. 

Geothermal energy is harvested by drilling a hole extremely deep into the Earth, past the Crust and into the Mantle. The hole is fitted with piping that allows fluid to be pumped down into the extremely hot layers of the Earth, where the fluid boils, expands, and is returned to the Earth’s surface, to the power plant, to run through a steam engine turbine to produce electricity. The same fluid cools and is re-pumped back into the Earth. 

There are many possible configurations and differences between setups, some requiring more or less construction, some requiring deeper holes to be drilled. I’m not intending to teach the specifics of how to build a functioning geothermal power plant, just a simple overview.

Geothermal is such an excellent choice for a source of renewable energy because it checks all the boxes. 

It is infinite and renewable, as the heat within the Earth will continue to constantly be produced. 

The power plants that harvest the energy can be build nearly anywhere on the planet. It might be easier to build them where the distance to the Mantle is shortest (so not on mountains), but the Mantle exists under all the Earth, and could even be harvested from the ocean (though that wouldn’t probably be practical). 

There is nothing toxic involved in the process and it is totally carbon-neutral because nothing is being burned. There would be much less maintenance required for this sort of power plant because of the lack of a combustion chamber, and no need to clean or filter any exhaust products. The water or fluid being used in the turbine will be constantly recycled and so won’t need to be treated or replaced. 

This energy source is extremely powerful and limitless. This would work very well to create electricity but wouldn’t directly apply to cars and trucks without switching to electric cars that run on batteries.

While a combination of all these options would probably work the best, diversifying our investments in energy and allowing experimentation in many directions, I think it isn’t necessary. I think we can narrow down to geothermal for all electricity production, electric vehicles which run on battery storage which can use the geothermally produced electricity, and for any vehicles not running on battery power, alcohol and biomass can be used.

Geothermal seems to be a perfect and total solution to our energy dependence problems as well. Each country depends to at least some degree, on trade with foreign nations to obtain all the energy they need. They work to import and export fossil fuels. But with geothermal, the power plants can be built anywhere, so each nation can have their own supply.

I don’t really see why there is any further discussion about where to invest green-energy dollars. Geothermal is the solution. It is renewable and independent. It is clean and safe. It doesn’t require any strange or rare materials. I see no downside. 

I think a real, firm step towards a real-world, literal utopia would be to invest in geothermal, and continue to do so to the degree than electricity becomes nearly free. Once humanity has its energy needs fully satisfied, it can set its sights on accomplishing bigger goals.

Please tell me what you think in the comments. Am I wrong? Am I mistaken? Do you agree?




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