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Solar from Space

How Space Solar Power can be implemented in the near future

Rocket Launch from Cape Canaveral Florida (Photo by SpaceX on Unsplash)

The future is demanding green energy, and today that’s more apparent than ever. Countless green solutions have been executed but none have been as effective as the fossil fuels killing our planet. The solution may be a new twist of current renewable technology, solar panels, and modern satellites. The coolest partnership in the universe!

Today I will be exploring how we could implement both solar panels, and satellites together to harvest efficient green energy from space, and how this is better than today’s renewable energy methods. Then I can explain what we would need to do to make this technology feasible.

First, we’ll need to know how both technologies work separately to go deep into how they will work together!

Solar Panels

An Array of Solar Panels (Photo by Jose G. Ortega Castro on Unsplash)

Solar Panels are powered by the technology of solar cells, which create energy by catching photons/light particles from the Sun. These photons are then used to knock electrons free from the solar cells which creates an electric current. Using wires, the current is then transported into an inverter, which then changes its wavelength and transforms the current into AC power. The energy is then ready to be used for use in places like your home!

Solar panels are typically made of silicon and many solar cells, which are usually about 36 square inches. A solar panel can have a configuration of either 32, 36, 48, 60, 72, or 96 cells, and can produce from 250 to 400 watts of energy per day. The typical solar panel system used in homes will produce between 1 and 4 kilowatts of energy each day.

Solar panels harvest renewable solar energy, an infinite energy source from the sun. Solar energy, therefore, doesn’t rely on fossil fuels and does minimal damage to the environment. Making it renewable energy!

In 2017 a report from the IEA (International Environmental Agency) also showed that solar energy is the fastest-growing renewable energy source in the industry, which is largely credited to the massive improvement in solar panel technology in the past decade.

Now that you have the basic rundown of solar panels let’s get another rundown on the second component of our technology: satellites.

Satellites

Satellite orbiting Earth (Photo by NASA on Unsplash)

Satellites are defined as an object that orbits either a planet or sun. So in reality, almost anything could be a satellite, a planet, a machine, a moon, or any other object as long as it orbits a planet or star. Most satellites are launched into space by a rocket and then when its speed overcomes Earth’s gravitational pull, it will then orbit the Earth.

What we usually refer to as a satellite are man-made machines that serve a variety of purposes such as communication, studying the Earth and other planets, predicting weather patterns, and tracking global warming.

Man-made satellites are being used on other planets such as Mercury, Mars, Venus, Jupiter, and Saturn for scientific purposes.

Satellites form a delicate and complicated network in the sky as well. To make sure that the 7,500 satellites don’t collide with each other, NASA and other international space organizations keep a close monitor of all satellites so we won’t need to worry about the widely important infrastructure of the system we have being destroyed by itself.

Now that we know the basics of how both technologies work, it’s time to go into how we can combine them to create green energy.

Combing the Two

A satellite with Solar Panels attached orbiting Earth

To create solar power outside of Earth we first need to make sure both pieces of technology can work together in the vacuum of space. We know that this is possible because we’ve seen solar panels in space before on projects like the International Space Station. However, to make it feasible and efficient, we need to create and transfer as much energy as possible while using as little energy as possible.

Northrop Gunman and Caltech are partnering up to create an array of photovoltaic solar panel satellites which means that the solar reaction would occur between two photons, catalyzed by the sun’s rays.

It’s important to remember that photovoltaics is the direct conversion of light to electricity on the atomic level. A lot of the tech we’ll be talking about uses this cool emerging technology!

Infographic showing how Photovoltaics work

To make it worthwhile we would need to harvest a large amount of energy and the best way to do it would probably be through an array of smaller satellites rather than one large one so they’d be easier to transport and easier to design.

With the recent advancement of technology in all these sectors we now know how to take advantage of photovoltaics, laser beams, and microwave power transmissions to wirelessly transfer energy from these satellites to Earth and be received by a ground receiver.

We will need our satellites to be equipped with the proper antennae so energy can be beamed back to Earth, whether that’s using laser beams or microwaves (we’ll talk about that below).

Now that we have an understanding of how we will combine the two. We have two ways in which we could transport our energy to the surface and we have to make sure the most efficient way possible is implemented to make this energy source worthwhile.

Laser vs Microwave

Our energy can be transported back to Earth in two ways, either through microwave or laser beam transmission. Each brings its own set of advantages and disadvantages to the table which we need to address when deciding which one we will pick to bring our energy to the surface.

Let’s start off with laser beam transmission

Infographic simplifying how energy can be transferred from space to Earth

In laser beam transmission, a laser beam sends concentrated light to a photovoltaic cell receiver and it works through these steps

  1. Taking direct current or DC energy from space and using it to generate monochromatic (single wavelength) light beams using the solar cells found in the satellite
  2. An optics system integrated into our satellite will then shape the laser light to the right size so our photovoltaic receiver on the surface can accept it
  3. A control system in our satellite then makes sure that our laser is pointed to the exact area of our receiver on earth
  4. Our energy is received and transformed using photovoltaics on Earth and can be used as green energy!

Laser beam transmission has many advantages including that it won’t interfere with TV, Wi-Fi, Cell Phone, Radio, and other communication signals when being transported to Earth. Laser transmission also requires smaller transmission and receiving equipment compared to microwave technology.

On the other hand, laser beam transmission will suffer from atmospheric losses due to environmental factors such as clouds and rain. Laser beam transmission also has a low conversion efficiency using a lot of energy in the conversion to usable electricity.

Now, let’s take a look at microwave transmission

Infographic demonstrating microwave power can be transferred from space

Microwave transmission is sent to Earth in generally the same way with a few key differences that you don’t see in laser transmission, you can see how the energy is transmitted in the following steps

  1. Taking direct current or DC energy from space and using it to generate RF or Radio Frequency light beams rather than monochromatic light beams like the ones we see in laser transmission. This conversion happens using the solar cells built into our satellite
  2. Our satellite will then create a highly concentrated microwave beam (concentrated even more so than our laser beam). That can be aimed at the corresponding receiver on the surface
  3. The receiver on Earth can then collect and the RF light beams and convert them directly into electricity
  4. Once our light beam is converted into usable electricity using photovoltaics, the energy is ready to be used as green energy!

This method also presents its set of advantages such as its usage of highly developed microwave technology, which presents an 85% energy retention rate during transportation from space to the surface. However, this method may interfere with radio waves and will require large transmission and receiving equipment.

All in all both methods come with their advantages and disadvantages and it really depends on what we will prioritize to pick a better solution.

So, we have all this information on how to implement this technology. Is it even feasible?

Feasibility

An example of a satellite dish you can see today (Photo by Donald Giannatti on Unsplash)

Today we are at a turning point where the feasibility of this technology is actually becoming a reality. A solar panel in space is about 35% efficient compared to a maximum of 20% on Earth, and with the renewable energy sector valued at almost 700 billion US dollars, the technology will continue to improve.

Currently, wind energy dominates renewables by a huge margin and will be more effective than our space-based solar power as it is cheaper, easier to install, and produces more energy per hour.

Even hydropower is more feasible due to the lower price tag and of course the amount of ocean we have to place hydro dams. It’s much easier to build a green hydro dam to power New York City than to send energy from orbit down to power the city of almost 9 million people.

We also just don’t have the level of technology yet to make it feasible to transport the energy back to Earth in a way that’s more efficient than current renewables, even though the power generated from space would still be much more efficient and produce more than current renewable technologies. The problem is the last step of getting the energy from space down to Earth, similar to how the most expensive part of the fulfillment chain for packages at Amazon is the last-mile delivery. In this case, the last mile blows cost out of proportion and removes the viability of the technology.

Hopefully in the future companies like Northrop Gunman will be able to lower the price of getting the energy back to Earth, making space solar power a new piece of technology contributing to green energy for all.

Additionally, launching a satellite to space can cost anywhere between 10 and 400 million dollars depending on the weight and size. This is not something that we can afford to do on a regular basis when there are much cheaper alternatives available on Earth. This cost could decrease quickly in the coming years with large investment into the space sector from companies such as SpaceX, Blue Origin, Boeing, and governments around the world including the United States, Canada, the EU, Japan, and China.

Still, our space-based solar power is still extremely efficient and produces much more than panels back on Earth.

And there are still two niche energy markets that space solar power would fit right into…

Powering the New Frontier and helping us on Earth!

Illustration of what a future solar satellite orbiting Mars could resemble

Space solar power has one place that it fits perfectly into: Powering space, from space! Today producing energy in space is a huge problem and space solar tech is the best way to do so. The International Space Station and our satellites are dependent on solar power and this can be implemented in more technology we use in space today!

For example, putting any object into space takes a ton of energy (quite literally a ton of rocket fuel). If we can develop the technology and implement power stored from our super-efficient solar panels and use electric power in spacecraft, it would drastically cut the cost of space travel and could incentivize it further.

Solar energy from space can also be a valuable resource when trying to develop infrastructure in space and on Earth.

In space, having energy available to research and develop infrastructure is extremely valuable and is a huge factor in what’s holding back space infrastructure and the development of space technology today. For example, if we wanted to start infrastructure and a potential colony on a different planet shipping everything from Earth wouldn’t make sense in the long run.

If we had energy directly produced and from satellites orbiting the planet, it would be much more efficient to deliver and produce the energy and beam it directly down to the planet for projects and to continue developing infrastructure. The colonists would also have direct access to energy to produce resources when needed without the need to wait on shipments from Earth which would take about 7 months.

The need for energy on Earth would be smaller, but the huge benefit of space solar power in this situation is that it can be transported to almost any location on the planet by laser.

This is extremely valuable when needing to bring energy to a remote place for development or for a short period of time without spending resources on infrastructure you’ll only need once. Imagine being able to beam energy directly to remote communities that are underserved by their current energy supply. Think of communities cut off from major infrastructure, refugees trapped in a nation at war, and scientists researching in remote areas. All places where this technology presents a major advantage here on Earth.

In Conclusion

Satellite orbiting Earth (Photo by NASA on Unsplash)

After reading this article, I hope you learned about space-based solar power and how it could be implemented in the near future and how we can make it feasible on the level of our current renewables.

Space-based solar power is far from being a replacement for current renewables such as hydro or wind power. However, this technology can fit right into some niche areas where other renewables won’t make the cut and with further development, space solar power will make an amazing addition to our catalog of green energy powering our future.

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Gabriel Bernal

Gabriel Bernal

Hello! My name is Gabriel, I’m a 9th grade TKS Innovator looking to create meaningful change in the world. LinkedIn:www.linkedin.com/in/gabrielbernalonline