Five Alternative Forms of Energy You Have Never Heard of
In my first article about alternative energy, I offered nine ways that we can generate electricity using renewable sources. For the most part, the methods discussed in that article have been tested, researched, and are familiar to the lay person. In this article I will shift gears slightly and discuss some forms of energy that aren't as well known as the others I have talked about before. Please keep in mind that some of the methods I will present here may be highly impractical (for the foreseeable future) or just plain out of this world. But perhaps at least one of the following strange energy production methods will one day become an integral way that civilization generates its electricity.
I'm not just talking about pedal power here. If you have seen the movie The Matrix, then you have seen the potential power that the human body can generate. There are two main ways that humans can be utilized to generate electricity to power external devices. The first method utilizes motion and movement to generate electricity. Devices that harness bodily motion can include things like kinetic generators as well as crank-like mechanical devices.The second method generates energy by utilizing the radiant heat generated by our bodies.
Kinetic devices are generally passive and generate electricity as you do normal tasks throughout the day such as walking, eating, and breathing. Kinetic generators are already in use in many pieces of technology including wrist watches, pacemakers, hearing aids, and even a few smartphone prototypes. Its foreseeable that kinetic devices could become so powerful and efficient that they could charge a typical cellular phone or even a laptop computer simply by walking around.
Mechanical devices, such as bicycle generators, are active devices that generate electricity only when the user is turning the crank. There are many instances where the electricity generated by this method has been used to power a television set or even a desktop computer. Most often the efficiency of this type of activity is on the order of 2.6-6.5% and has already proven its viability on a large scale operation. Just take a look at some of the human powered gyms that Hong Kong has.
The second method involves capturing the heat that is naturally radiated from our bodies by using a biothermal device. These devices already exist on a small scale and are being used to power pacemakers. The great thing about this form of energy creation is that no actual movement is needed to generate the electricity (just calories burned).
Energy from Noise and Sound
If you have ever been to a rock concert, then you are certainly no stranger to the deafening power of sound. Since sound is a vibration that travels through a medium, it's possible for that energy to be captured and redirected into some power generation mechanisms. If a speaker can convert electricity into a sound, then a piezoelectric sensor would be the machine that could do the opposite. Most sound to energy devices that exist utilize piezoelectric devices to directly convert vibrations into energy. There have already been prototype cell phones that can charge themselves simply by speaking (or yelling!) into the microphone.
There have been plenty of other concepts for ways to generate electricity from sound, but most have aren't viable on a large scale. Most of what science has to offer at this time is a novelty item at best. However, one concept that may prove useful on a large scale is a device that uses a large "drum" to move air in and out of a chamber as it vibrates. This moving air turns a small turbine which is then able to generate electricity. Perhaps someday "sound farms" that generate power from the ambient sounds of our noisy world will become just as common place as wind farms are.
Energy from Rainfall
Another energy concept that utilizes piezoelectric sensors is the idea of converting the impact energy of raindrops into power. Imagine covering your roof with these devices and being able to live off of the grid every time a nice storm rolls around. Better yet, why not combine rainfall energy harvesting techniques with that of solar plants. In essence you could have a power plant that generates electricity from the sun as well as precipitation.
The latest research into this technology has shown that rainfall has enough energy in it to power many of the small devices we already use everyday. If the efficiency of these devices can be increased, rainfall energy may become practical on a large scale.
Yes, there are ways to generate electricity from pee! According to the Royal Society of Chemistry, researchers at the Bristol Robotics Laboratory created a microbial fuel cell (MFC) capable of generating electricity from urine. In the experiments, just 25ml of urine was able to generate 0.25mA of electricity continuously for a periodic of 3 days.
While utilizing pee-power to run your computer seems highly impractical, consider the abundance of this chemical in our world. Each person on in the USA generates about 2/3 of a gallon of urine per day and most of it ends up in the wastewater stream. When you factor in your the waste generated by pets and farm animals, the amount of urine available each day for energy production is enormous. Imagine if all of that liquid waste was recycled and used to power our world? Perhaps in the future urine could become as valuable as any other material for our power needs.
What happens when you combine the concepts of geothermal energy with that of the urban heat island effect? You get a new source of energy that's what! Typical urbanized environments experience unnaturally higher temperatures due to the fact that so much of the ground surface is covered by asphalt and concrete. These materials have the ability to retain lots of heat. Anyone living in Arizona will confirm that the pavement can get quite hot in the summer. You can literally fry an egg on the street because it is so hot (people have also been hospitalized because they tried to cross the street with bare feet).
The concept to generate power is simple, inside of the asphalt pavement is a serpentine system of pipes that circulate a liquid such as anti-freeze or water. The water is warmed up and could be pumped into a heat exchanger located inside of a nearby power plant. The heat can be used to generate steam to turn turbines. Alternatively, the warm water can be used directly in lieu of using traditional or solar water heating methods. Another concept allows the natural circulation caused by the water's increase in temperature to turn turbines directly. With all that heat being stored in our infrastructure it may one day prove viable to harness the energy of our urban heat islands.
References and Resources
Alternative Energy. Forget Solar, Human Power is the Future. February 19th, 2010. <http://www.alternative-energy-news.info/human-power-is-the-future/>
Biophan Technologies, Inc. Biothermal Power. 2011. <http://www.biophan.com/dmdocuments/Biothermal%20pullsheet%20FINAL.pdf>
Broadwith, Philip. Pee-Powered Fuel Cell Turns Urine to Energy. October 31, 2011. <http://www.rsc.org/chemistryworld/News/2011/October/31101103.asp>
Cattermole, Tannith. Mobile Phones Charged by the Power of Speech. September 20, 2010. <http://www.gizmag.com/mobiles-powered-by-conversation/16417/>
Ceclia @ Innovative News. Top 5 Unusual Ways to Generate Power. July 28, 2008. <http://www.sikantisearth.com/earth/?p=129>
Chapa, George. Could Sound Power Your Home? June 6, 2007. <http://inhabitat.com/sound-could-power-your-home/>
Gilmore, Adam M. Human Power: Energy Recovery from Recreational Activity. January 14, 2008. <http://www.soe.uoguelph.ca/webfiles/gej/articles/GEJ_001-008-016_Gilmore_Human_Power.pdf>
Zimbabe Metro. Scientists Say Urine Can be Used to Generate Electricity. November 18, 2011. <http://www.zimbabwemetro.com/30709/scientists-say-urine-can-be-used-to-generate-electricity/>
© 2011 Christopher Wanamaker