Chris is an engineer, thinker, and philosopher who enjoys exploring futuristic ideas and technology.
Over 86 percent of the energy consumed in the United States comes from petroleum, natural gas, or coal. Unfortunately, our dependence on these nonrenewable resources could someday lead us straight to our demise. Without change, society as whole would be immobilized. But why wait for the inevitable when we can enact change now? Here are 9 sources of renewable energy that could potentially change how we power our future.
Currently, hydroelectric power plants provide only about five percent of the energy used in the United States. This type of power is more than a few centuries old as it has been used to power grain mills and other farm machinery. Unlike the water wheels of the past, modern hydroelectric power plants start with water stored in a reservoir behind a dam. The dam operators release water in a controlled manner through a spillway and over a turbine to generate electricity.
However, these types of power plants are not the panacea for our energy needs. In general, these structures have a relatively short lifespan and are prone to catastrophic failures. Another downside to hydroelectric power plants is their sometimes negative impacts on the environment. For example, in some areas whole populations of salmon have become eradicated because of their inability to swim upstream due to the presence of a dam. Downstream sediment transport is also blocked. This causes a severe reduction of nutrients in the water as well as excessive downstream river erosion. And finally, another problem with dams is finding an appropriate location to build them. There must be enough depth and space behind the dam to create a man-made lake, without destroying cities and natural life.
Geothermal energy works similar to a large heat exchanger. Deep in the earth's crust, heat from magma chambers and volcanic activity can be utilized to generate steam which can turn turbines. Alternatively, natural steam rising from crustal vents in the ground can be captured and directed into a power generation facility. The hot water vapor is directed towards turbines, which generate the electric power.
Geothermal power plants can also have very a short lifespan. Sometimes, the hot spots near the earth's surface can become inactive or run out of steam. The best geothermic sites have a magma chamber neither too shallow nor too deep from the surface. Ideally, a good geothermal site would also need to have natural channels or inlets, to constantly supply the hot magma with water.
One study indicated that if all the winds of North and South Dakota could be harness, it would provide 80% of the electrical energy used in the United States. Similar to hydroelectric power, wind power has been used for centuries. In the days of the old, it was used to turn grain mills or pump water. Nowadays these devices are very simplified. Basically, wind flows over a huge propeller that turns a turbine and generates electricity. Wind power stations provide a good amount of power in relation to the cost it requires to build them. They are inexpensive to build and are generally safe to use.
However, this technology does have a few downsides. Wind power farms usually create a lot of noise pollution. They could pose a problem if built near homes or in cities. Spinning propellers also pose a signicant problem to our bird populations. Additional, wind power is not completely reliable nor is it very efficient compared to other sources of energy. Despite these challenges, wind power is one of the most promising sources of alternative energy that scientists are considering today.
To harness the power of the tides you have to construct a dam or gate structure near the mouth of an ocean bay that has a large tidal range. The in and out flow of the oceans water is then used to move paddles which turn turbines to generate electricity.
Although this is a really great idea, it is not very practical. Most of the world’s coast does not have a tidal rise and fall large enough to create any usable amount of power. Current research suggests that the range must be at least 25 feet or more for sufficient power to be generated. It is also very hard to find suitable locations to build this kind of power plant.
Ocean Current Energy
Harnessing the power of the currents of the ocean is not a new idea. In the vast oceans of earth, there are currents that constantly travel the globe. The currents churn the sea in a never-ending underwater ‘river.’ This untapped source of energy may provide the electricity of the future. The concept is simple. A stationary set of turbines would rest in the ocean and would be turned by the natural movement of the water. This power generation facility essentially acts like a wind power plant except that it is constructed underwater. Challenges with this proposition include find a suitable location with enough water movement, constructing a machine that can survive the ocean, and preventing environmental damage.
Oceanic Thermal Energy
Between the Tropic of Cancer and the Tropic of Capricorn exists a portion of the ocean that experiences significant thermal stratification. These relatively shallow layers of water with varying temperatures have the potential to create electricity. To harness this energy, you would need to use a heat exchanging device to turn a turbine. However, in the case liquid ammonia would need to be piped through the system instead of water because of its low boiling point. Cold water from the lower layers of the ocean would be pumped into the system to cause the ammonia to condense. Then when it warms up in the hot layer of the ocean, it would turn back into a gas creating enough pressure to rotate a turbine.
Although a unique idea, current research shows that it is not likely to be very efficient. In addition to this, it would be difficult to transmit or store the energy generated from this to use where it is needed. Even so, this idea is not completely of off the table.
About seven percent of the energy consumed in the United States comes form nuclear energy. In this type of power plant, radioactive materials release energy by a process of nuclear fission. This energy is used to heat water that turn turbines to create electricity.
While this type of power plant can generate immense amounts of energy, many significant challenges and roadblocks exist for nuclear energy. These power plants are also very expensive to build and require a feasible way to dispose of the toxic waste. The perceived fear of terrorism and nuclear disasters is another roadblock for these clean and efficient power plants.
More recently though, there has been extensive research into the viability of Thorium as a greener and safer alternative to traditional uranium nuclear power plants. Thorium is much easier to find in nature and produces less waste. The process by which energy is extracted from this material is also different from that traditional uranium reactors. Expect to see more about this form of nuclear fuel in the future.
Have you ever thought about harnessing the immense energy located in lightning? The concept is simple. Large tesla-coil like devices would sit atop mountains and beckon the lightning to strike them. Lightning would strike metal rod in the device and electricity would be directed to large capacitors for storage. Then, the stored energy could be released slowly as it's needed to power homes and businesses. However this power source is not without its problems either. Energy from lightning is not very reliable and would never become a main source of power. Lightning and the high voltages associated with it are also very dangerous.
Solar (Photovoltaic) Energy
Solar power has been touted as the panacea for solving our society's energy problems. In theory, there really is no better alternative source of energy than what can be harnessed from the sun. The abundance of plant life covering the earth's surface has used sun to generate energy for millions of years. Life on earth as we know it could not exist without the sun. For a number of reasons, this celestial body is also the perfect energy source for all of humanities needs as well.
With the cost to design, locate, and build new solar plants declining rapidly, and the efficiency of energy collection increasing, it won't be long before these facilities become an everyday symbol of energy independence in our society. Solar power is passive, quiet, and requires little maintenance. In addition, most materials needed to create solar panels are readily available.
One downside to solar power is that these facilities typically require significant areas of land. However, if a decentralized approach to solar energy is employed, then solar panels can be placed on rooftops and parking structures. This adds diversity to the grid while also minimizing the impact to the environment. Another downside to solar power is that they can't generate electricity at night nor can they perform well when it is cloudy or rainy. For this reason, large batteries are often needed in order to store the energy generated by the panels for use on days with poor solar radiance. For now, most batteries are made with lithium, a rare material, however, new battery technology will one day help to make solar power the ultimate energy source.
In consideration for the future, we as a race will find it necessary to reduce our dependence on non-renewable resources such as petroleum. As with anything else in this world, nothing comes without a downside. For petroleum it was obvious. The future lies not with just one type of power plant, but with a variety of renewable energy sources, including some lesser known sources of energy such as biomass, used wisely in conjunction with the smart use and transmission of the electricity they generate.
This content reflects the personal opinions of the author. It is accurate and true to the best of the author’s knowledge and should not be substituted for impartial fact or advice in legal, political, or personal matters.
Questions & Answers
Question: Can you generate energy from stars?
Answer: Yes, generating energy from stars is certainly possible. First and foremost, the sun is a star. So in its most basic form, the solar energy that we generate all across the globe today is really star energy.
Many space vehicles use solar technology to generate energy for propulsion. "Solar Wind" can also push space vehicles along. In addition to this, many scientists have proposed "MegaStructures" can would, in theory, more directly harness the abundance of energy found in stars. Of course, we are a long way off from this kind of technology.
However, if you are thinking of constructing "star panels" to harness the energy of the glowing night sky, you will probably be disappointed. The technology we have available now is so inefficient that any energy obtained from starlight would likely be lost before it can get to a place where it can be used or stored.
Question: Is biomass energy a renewable energy source?
Answer: Yes, biomass energy is a renewable energy source, for the most part. Biomass energy is sourced from incinerated vegetative waste, trees, etc., to produce heat and energy. If the biomass is obtained using sustainable practices, then it is renewable.
Question: Can you generate energy from moonlight?
Answer: It's certainly possible that solar panels can be invented and erected that would capture some of the energy that comes from the moon. However, due to the efficiency of today's panels, the phases of the moon, and the how little light comes from the moon (which is just light reflected from the sun) it's not likely that moonlight would ever become a viable source of energy. Based on my research, the amount of energy coming to earth as moonlight is about 2.3 million times smaller than what comes to earth from the sun. These things make capturing energy from moonlight highly impractical.
Question: Can we use liquid hydrogen to generate power?
Answer: Liquid hydrogen is a fuel that could be used to generate power on a small scale. The most likely future application of this is in hydrogen vehicles. Hydrogen-powered vehicles are equipped with a fuel cell that is filled with hydrogen. The fuel cell helps keep the liquid hydrogen stable while it is being used.
However, one of the problems of hydrogen is that it is a secondary energy source. Hydrogen has to be manufactured before it can be useful as a fuel. Manufacturing hydrogen requires energy and due to the law of conservation of energy you cannot get more energy out of something then you put into it. In other words, it takes more energy to create hydrogen for fuel than the amount of energy we get out of it as a fuel.
The other challenge with hydrogen is infrastructure. At most temperatures on earth, hydrogen wants to be in a gaseous state. Storing it means that the containers must be perfectly sealed and capable of withstanding high pressures. Since hydrogen is the smallest atom, even the tiniest leak in the tank or pipes will allow hydrogen to escape. This is a challenging problem to fix.
Question: Can electricity be generated with falling rainwater droplets?
Answer: Yes, researchers are currently testing several new technologies that can generate electricity from falling raindrops. Such technology uses something called a piezoelectric cell which can take kinetic energy from motion and convert it into electricity. Another device that is being tested collects the rainwater in a tank and then releases it over turbines to generate electricity much like a waterfall or a water wheel. A third technology that shows great promise is one where a special coating is applied to a solar panel so that during rainstorms the energy from rainfall can be captured by the panel.
Question: We have long highways all across the country. When vehicles and trucks pass by a point, it generates a lot of wind. Is it possible to generate power using this wind?
Answer: Yes, it is certainly possible to collect energy from wind generated by vehicles traveling down the highway. This sounds like a pretty good idea. However, there may be downsides such as how to practically implement it. Also, this may not be an efficient way to generate energy. In any case, I believe that this is certainly an idea worth researching.
© 2011 Christopher Wanamaker
Jnanesh Sharma H on April 05, 2020:
Wow, well-written article. I loved the way you describe the nuclear power and lighting energy. Even I wrote an article for HubPages. I hope you would like it. http://hub.me/anqVa
Peter on January 21, 2019:
Nice article, please research more, Nevertheless you did a great job
Christopher Wanamaker (author) from Arizona on July 22, 2018:
Biswabijet - I can't recall my original reason for not including solar energy in this article so I went ahead and just added a section on the topic. Thanks for your input.
biswabijet on June 25, 2018:
it is odd that solar energy has not been mentioned, unlike other sources of energy.This renewable energy source does not hamper the ecosystem ,i do consider the low efficiencies of the solar pv cells but still it is a lot safer compared to nuclear ,which according our worthy comrades report to diminish from 2025.While on the other hand Sun is a medium star which has estimatedly 5 billion years more to live ...
Brian on May 27, 2017:
What a difference 5 years makes. Now solar and wind are available the cheapest of all energy sources below 3 cents per KWH.
140GW of solar and wind were installed last year.
over 5% of the USA electricity is from wind. 2% from solar pv.
Lightning is only about 20KWH per strike.
Nuclear power will be short of uranium in 2025 after supplying only 2% of the world's energy. Nuclear is not renewable in the slightest. Apparently, most people don't know this.
The IAEA says that we will have uranium shortages starting in 2025, then getting worse fast.
Pub1104_scr . pdf "As we look to the future, presently known resources
fall short of demand."
Fig 16 show the shortfall in 2025
fig 20 also show shortfall.
Arun Dev from United Countries of the World on July 12, 2015:
It is very necessary to save the planet Earth, which is the reason we could evolve and live. Renewable energy sources are some good options in this regard.
Seshagopalan Murali from Chennai, Tamil Nadu on June 29, 2015:
The hub is cool with detailed explanation. The most interesting fact is the lightening energy which was new to me.
stephiene meyer on March 21, 2015:
good,but its too much lengthy
Anna Sternfeldt from Svenljunga, Sweden on April 01, 2013:
I can't see that clean energy is a luxury, it is a must. But cars and transports can be luxury and other stuff, we need energy to be able to produce food and to heat our houses, and these are the basics.
coco-codi on April 01, 2013:
what happens to the land that the wind turbines sit on does the land become solely wind turbine "turf" or is the land farmable if not how is it sufficient in renewable sources when our food is more vital to survive compared to a luxury of "clean energy"
shit on January 31, 2013:
Alternative methods of Generating Electricity research
Anna Sternfeldt from Svenljunga, Sweden on January 01, 2013:
Great with discussions on this matters as we urgently must find solutions to replace fossil sources. As you and participants in the discussion have pointed out, there is really no energy source that could itself replace fossil fuel or provide us with most of our needs or even be as you say stable and reliable. And that is likely the future we have to face and accept. We have to be flexible. We need to use different kinds of sources and technologies.
As you, I am also aware of the ecological difficulties with hydropower and dams, so I don't think we should develop this anymore, but use the facilities that are already in place. Wind has its issues as mentioned, but I also know that there are wind plants that are not so noisy and also have addressed the problem with birds, so I think there are things happening here that will give us better plants, but as mentioned earlier, it has to be combined with other sources. Sun of course, and the ocean is interesting, it is huge and powerful so it has a potential for delivering energy, but sure... the technology is not there yet.
Geothermal energy has a good potential in certain areas, for instance in Nicaragua, where there is pretty much thermal activities close to the surface. I have been there once and visited a power plant.
Nuclear energy is as I see it not an option. Too dangerous, no solution for the waste and it is not even economically viable when you calculate all costs included. The same with the usage of Thorium, not a sustainable economically viable option.
R.NAGENDRA on December 09, 2012:
I have a new idea to generate power from running trains for better implementation how can i contact in with u
Christopher Wanamaker (author) from Arizona on May 24, 2012:
G.srikanth - Yes, there are plenty of other methods available that can be used to obtain renewable energy. If you are interested see my many other hubs on this subject. I have one called "Five Alternative Forms of Energy You Have Never Heard Of" that poses some unique solutions to our power problems. In addition to this, I have written about biomass energy and thorium power plants.
G.srikanth on May 24, 2012:
Is there any chances other than this.
jerrysaliu from Warri, Nigeria on December 07, 2011:
Christopher Wanamaker (author) from Arizona on December 05, 2011:
Jennifer Essary - Thanks for stopping by. Since this hub is pretty popular, I may write another one discussing additional sources of energy.
Christopher Wanamaker (author) from Arizona on December 05, 2011:
Princesswithapen - Hey, Thanks for sharing! I felt that solar energy deserved its own hub, which I will write sometime in the future. Traditional nuclear energy does have some major issues. However, if we used Thorium as a fuel instead of traditional Uranium-235/238 in reactors, most of the issues associated this type of energy would be eliminated. I wrote a hub about Thorium if you are interested. https://hubpages.com/technology/Powering-Our-Futur...
Jennifer Essary from Idaho on December 05, 2011:
Excellent hub on a topic that deserves a great deal of attention. Voted Up!
princesswithapen on December 05, 2011:
What about solar energy? It's unfortunate that nuclear energy has massive downsides when it comes to destructive uses and other dangers of radiations. Classic example of its danger was seen during the Tsunami in Japan, like you've rightly pointed out. Interesting hub which gives an overview of the many available energy sources that mankind has not fully tapped. I'm sharing it with friends and followers.
John Coviello from New Jersey on September 26, 2011:
There are limitless way to generate electricity from renewable sources. Many doable today or within reach within a few decades, and some that will require technological advancements far in the future.
Some I have read about include wind mills floated up into the jet stream to harness the wind energy that is much stronger and more consistent at high altitudes. Floating wind and wave electrical generating ships that generate electrify from the wind and wave action on the oceans then unload their electrical cargo on land. Solar arrays in space that beam electricity down to earth.
Regarding Larry's concerns about wind not being available for base electricity needs. That is true today, but perhaps not much longer, as large utility scale batteries and electricity storage methods become technologically feasible.
Thanks for this excellent Hub!
Kristin Trapp from Illinois on September 26, 2011:
These are all very interesting ideas. I have read about harnessing the power of the ocean before and found it intriguing. I had not heard of the lightening idea up to this point, but it has some value too. I just think all of this shows that there are other methods than what we have traditionally relied upon and diversification maybe is what is needed to provide people with power.
Christopher Wanamaker (author) from Arizona on September 25, 2011:
Well said Larry. I agree that wind power is overrated and unreliable. Personally I believe that the future is with Concentrated Solar Power and possibly Thorium. None of the other sources of energy are very reliable or practicle on a large scale. I still have much to learn about thorium though. As far as I can tell, its future is uncertain.
Larry Fields from Northern California on September 25, 2011:
I have a few comments about wind energy. First, an innovative design, called the Mamikon Spinner, may be prove to be superior to the convention propeller models. Future research will determine which is the more efficient design. However birds and bats will be less tempted to fly into Mamikon Spinners. That's the good news.
Now for the bad news. Winds turbines don't do squat for peak loads, because they're not dispatchable. Except in a few windy areas, wind turbines are not sufficiently reliable to contribute much to base loads either.
Except in areas with abundant hydro, wind turbines increase the need for natural gas turbines, which are dispatchable. The upshot: When you introduce wind power into the mix, you burn more natural gas, but less coal. Is that a good thing, or is it a bad thing? My unequivocal answer: Yes.
The Brits have already reached the point of diminishing returns with wind power. At times, they're actually paying windfarms to turn off their bloody turbines, because the beasts introduce too much instability into the system.
In most places, it is not realistic to get more than 10% of your electric power from wind turbines. Moreover even that small 'green' portion of electricity generation can greatly inflate electric bills. Ask the shivering British retirees, who must choose between good nutrition and adequate heat during their increasingly cold Winters.