Wireless Energy Transmissions: Making the Seemingly Impossible Possible

 In 1901, Nikola Tesla began the creation of the Wardenclyffe, a “power tower”, foreseen to one day be able transfer energy wirelessly in all directions around it. But, soon after this project had begun it was scrapped, and the tower with it, due to low funding and lack of investors.

Fig. 1 Tesla’s Wardenclyffe Tower

One hundred and fourteen years later, scientists have finally taken Tesla’s work to the next step, and have succeeded in transmitting energy wirelessly. JAXA (the Japan Aerospace Exploration Agency, or the Japanese equivalent of NASA) has harnessed the power of microwaves, directed this power at pinpoint accuracy at a small target, and delivered 1.9 kilowatts of power 55 meters away for the very first time, no wires attached. Scientists aim to use this technology for the generation of solar power in outer space. But 55 meters is miniscule compared to the 22,300 miles away that scientists aim to place these solar stations. Yet, this could be a major breakthrough in renewable energy: humans may one day be able to harness a virtually undisturbable, inexhaustible source of energy. In space, there is never a time of day or type of weather that is unfit for the capture of solar rays. And we still have billion years, give or take a few, until our sun begins to die. 

Fig 2. What the solar panels in space may end up looking like

Technology like this has existed previous, but in different forms. First of all, typically, energy, or in it’s usable form, electricity, is transmitted via power or distribution lines or wires. In addition to wired transfer, there are also two different types of wireless energy transmission: near-field or non radiative, and far-field or radiative. Near-field is somewhat newly conventionalized, but nonetheless relatively commonly used for charging devices, such as phones, electric toothbrushes, and cardiac pacemakers. You may have see this method in your local technology store as a mat that you can place your phone on to wirelessly charge.

Fig. 3 An example of near-field non-radiative technology: the wireless charging mat

The type of wireless energy conveyance that JAXA has just now harnessed is far-field, or radiative transmission. Also known as “power beaming”, radiative transmission occurs via beams of electromagnetic radiation, such as microwaves or laser beams. The solar space stations would use the microwave technique to beam precisely pinpointed streams of energy down to earth.

Fig. 4 Another idea of what the wireless space solar panels may look like

Though inexhaustible radiative wireless energy seems to be faultless, as with any new innovation there are challenges as well as possible flaws. How will JAXA move this gigantic solar system into space? How will they choose to construct it? Maintain it? I assume that this process of but moving from the earth into space, and position will take years. And, what will it look like from earth? Will we be able to see it?

Will it be efficient, more so than existing solar panels? Though they will certainly generate a massive increase in amount, I hypothesize that there will be energy lost along the way, as 22,300 miles is an extremely long distance. And if the beam is concentrated and powered high enough not to be inefficient, what will become of the people, animals or objects that get in it’s way? After reading comments on what informed readers believe will occur, I have come to the conclusion that, because this beam will be incredibly hot, it could cook or vaporize anything in it’s way. Though a JAXA spokesman has said that this beam will not fry a bird or airplane in it’s path due to low-energy density, it is hard to make solid conclusions when this method has only been tested in the range of 55 meters and not yet an exponentially larger scale.

Fig. 5 A third layout of how these panels may be aligned, and how they function

The station itself is bound to cost millions, if not billions of dollars, which will either drive taxes or the cost of energy itself up. In addition, JAXA has been working on this Space Solar Power Systems idea for years, and has only made it to the first, vital step: transmission itself, and for only a short distance. A representative from the Agency has stated that it could take decades before the practical application of the technology becomes a reality. News providers and science enthusiasts have speculated no earlier than the year 2030 or 40.

Fig. 6 A group of JAXA Scientists

Though wirelessly transmitted energy will not be an innovation of the near future, I believe that when the Space Solar Power System is implemented, and the method is working, that it will change the way we think of energy altogether. In fifteen years, nonrenewable resources will begin to dwindle. There will be unrest, and slowly our beautiful earth will begin to be saturated with turbines and panels, streaking across the landscape. An alternate option will be desired, if not necessary. And what better option than putting these energy collectors outside of our world entirely, and making them infinite? It is unavoidable to state that wireless solar space energy could very well be our future. And if so, it will certainly be a bright one.

Solar Energy: Abundant, but Inefficient!

This week I read an article from the University of Colorado website, “Solar Power”, which focused on the abundance and cost of solar energy. What intrigued me about this article was its description of how much solar energy is available, but not really useful to us now. This is due to the fact that the solar panels are simply not efficient enough. However, there is so much solar radiation in our atmosphere, the article claims, that we have 16,000 times our current needs of energy available to us. The only problem is that we cannot efficiently convert solar energy to electricity, or store it cheaply. This class has looked a lot at new technologies springing up around coal, oil, and other fossil fuels. Coal is very dirty, and hydraulic fracturing presents many dangers of its own as well. In fact, just last week, a train carrying oil from a fracking industry, blew up in West Virginia. This was because it was carrying both coal and oil, which are polluted and non-renewable resources. People around our country are praising the fossil fuel industry for bringing the cost of gas down in recent years. On the other hand though, this article actually informed me that there is far more renewable energy available from the sun than we will ever need. Our current problem in this area comes from photovoltaic panels (See below in Figure 1)

Figure 1: Active Solar Photovoltaics:

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A solar panel uses two layers of silicon with different charges, sandwiched between other kinds of metal to produce an electric current from sunlight. Right now, most solar panels available are only 10% efficient: if the panel absorbs 100 joules of sunlight energy, it only produces 10 joules of electric energy. Therefore, the technology is also expensive! The article shows how 1 kilowatt hour of electricity from coal can cost as little as 10 cents, and the same electricity from a solar panel can cost 50 cents, or as much as 85 cents on a cloudy day.

There has been such a focus of money and energy on coal and oil recently. If those same resources were put towards solar efficiency, solar panels might look a lot more attractive to consumers, and we might be able to tap into the vast resources from the sun.

Could Cheaper Oil and Energy Be Dangerous?

In the article titled, “Preserving Ancient Art In Land Marked For Solar Energy Development” by Jeremy Miller, we get a look at the dangers that come along with the benefits of the new fracking industry that has boomed in the US. Cheaper oil and energy seems to be a good thing, but there are prices to pay, including increased carbon in the atmosphere, which only speeds up climate change.  In fact, Figure 1 shows a chart of all the amounts of carbon dioxide emissions by the United States alone. (2)  As you could have guessed from Figure 1, carbon dioxide is the most popular greenhouse gas being released into the atmosphere by humans, harming the environment.

Figure 1: All U.S Carbon Dioxide Emission Estimates (2)

gases-co2

 

Alternatives would give us a brighter future, but they also come with problems. One example is the BrightSource Ivanpah Solar Power Facility, almost operational on the southern border between California and Nevada. This will be one of the larges utility facilities in the United States, “supplying nearly 400 megawatts of electricity, enough to power 140,000 homes during peak sunlight hours.” (1) This means 400 million joules of electrical energy every second. Compared with fracking, and the damaging pollution that it brings, an array of solar panels seems like a great idea. However, a whole list of issues has come up in the recent months while the solar panels were being installed. For example, the air around an active solar panel becomes heated. A large array of panels can create a “solar flux” (1), which is a pocket of super heated air that could rise and kill birds. This utility is built in the remote Mojave Desert, and may be endangering a rare species of desert land tortoise. This article shows that there is no easy answer to our energy needs. Even though peak energy consumption dropped off slightly after the 2008 recession, our country still needs to find clean, new, and efficient sources of energy that will have minimal impact on the environment. 

I always assumed that solar energy was good, and I was surprised at how many problems were arising from one energy plant. Another one that really struck me was the cultural impact: the land contains some ancient rock art from early Aztec people. Now the archeology is endangered. The descendants of those first natives still live in the area, but their communities are cut across by the array, and some of their native languages, which are only spoken by a handful of people today, are also now endangered by the solar panels. The result is that any new source of energy comes with problems, and these problems and issues need to be weighed against each other.

Sources:

(1) http://www.hcn.org/blogs/goat/preserving-ancient-art-in-land-marked-for-solar-energy-development

(2) http://www.epa.gov/climatechange/ghgemissions/gases/co2.html