Solar Energy Produced Directly From Space. Is It Even Possible? - Alternative View

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Solar Energy Produced Directly From Space. Is It Even Possible? - Alternative View
Solar Energy Produced Directly From Space. Is It Even Possible? - Alternative View

Video: Solar Energy Produced Directly From Space. Is It Even Possible? - Alternative View

Video: Solar Energy Produced Directly From Space. Is It Even Possible? - Alternative View
Video: Will our electricity come from space in the future? 2024, November
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More than seventy years ago, in 1941, Isaac Asimov wrote a story in which the energy of the sun was transmitted through microwave beams to neighboring planets using a space station. Years have passed, and today scientists are trying to translate this science fiction into reality on Earth. Concepts for harnessing solar energy from space or directly in space have been developed since the mid-20th century. Many projects are waiting in the wings.

Solar energy is the future

By using solar power in space (SBSP), we could solve our energy and greenhouse gas emissions problems with minimal impact on the environment. Professor Sergio Pellegrino of Caltech recently stated that the massive energy production of the SBSP system and the fact that our sun will continue to operate for another 10 billion years suggests that our energy source will not run out for a long time.

One of NASA's most extensive studies of all time, the Satellite Power System Concept Development and Evaluation Program, focused specifically on the SBSP and cost more than $ 50 million between 1976 and 1980. Another basic NASA-funded study to re-evaluate and understand the feasibility of SBSP was called Space Solar Power Exploratory Research and Technology. The study involved a huge amount of solid scientific research, but the overall conclusion was:

It is clear that nothing is clear. Let's dive deeper into the basics of this exponential technology and its feasibility.

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What is solar energy from space?

Solar energy produced in space is the concept of capturing solar energy in outer space and transmitting it directly to Earth or other nearby planets.

Simply put, we could put some kind of mechanism in outer space to capture the energy of the Sun almost continuously and transfer this energy to the Earth. This can happen day or night, rain or clear sky. Once we get the energy on Earth to the rectenna (a special antenna for receiving energy), we can easily distribute it using our usual methods. Everything is very simple.

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There are many ideas related to the configuration and architecture of the SBSP engine that we could use. System location, satellite architecture, power harvesting and power transmission are major major points to look at when understanding the various SBSP systems. Given the number of concepts on offer, we'll only look at some of the more notable options.

Where to locate the solar energy production system?

Geosynchronous, also known as geostationary, (GSO) orbit, medium earth orbit (MCO) and low earth orbit (LEO) are options to consider. The most promising is the GSO due to the simplified geometry and alignment of the antenna in relation to the rectenna, scalability and almost continuous power transmission. The main problem of GSO is a large amount of radiation. Common space hazards such as micrometeorites or solar flares also pose a threat.

Satellite architecture

Creating lunar factories with a lot of traffic, or developing asteroids for assembling or self-assembling SBSP satellites - in any case, creating autonomous space factories will be a difficult task. Any construction in space will require the use of local and free materials (that is, lunar), while it imposes certain restrictions on the complexity of the structures when compared with those that can be built on Earth.

One interesting installation we are currently building on Earth is a modular solar cell developed by Caltech and Northrop Grumann. Check out the video below.

Another interesting concept from the private company Solaren. In the future, she plans to experiment with the construction of a solar power plant SBSP with a capacity of 250 MW in geostationary orbit. In 2009, Solaren entered into an agreement with California's largest energy company PG&E to provide its space solar energy.

Even NASA's concept of an arbitrarily large phased array (developed in 2012) has garnered recent attention from John S. Mankins, one of the world's leading SBSP experts.

How to collect energy from the sun in space?

The two main concepts associated with energy harvesting are the use of photovoltaic cells (solar cells) or solar heat. You can capture solar heat (and thus energy) by using mirrors to concentrate light and heat the liquid. The steam, in turn, will rotate the turbine and generate electricity. This concept has a certain weight advantage over solar panels as it reduces the total weight per watt. However, most of the concepts are supposed to use ultra-light and highly efficient photovoltaic cells.

How to transfer the energy of the sun from space?

Microwave power transmission is a typical choice in SBSP designs due to its overall efficiency, but using laser beam power transmission is another interesting option due to its reduced weight and cost. However, the thought of a powerful laser beam raises the fear that it could be turned into a space weapon (death ray). However, security protocols could easily eliminate this threat. Designs can be designed to meet all microwave safety requirements. There will be no threat to the inhabitants of cities and living beings on the path of the rays to the earth. Simple feedback between the antenna and the rectenna would allow the transmission to be disabled if it deviates from the course.

Now that we have a better understanding of what SBSP is, let's dive into its biggest limitations.

Space energy transmission installation cost

It may seem that everything is fine and the sun will provide us with free energy for billions of years. However, there is always a catch. We have already noted a number of security concerns, but the main obstacle is the cost of shipping all the materials required for the SBSP. Current cost estimates for sending approximately 1 kg of payload into space range from $ 9,000 to $ 43,000, depending on the rocket and spacecraft used.

If we look only at solar panel shipping, the lower end of the cost spectrum for launching a 4MW ultralight SBSP system is 4,000 metric tons. But the SBSP will most likely be in the 80,000 metric ton range.

Low estimate: 4,000 metric tons x $ 9,000 per kilogram = $ 36,000,000,000

High estimate: 80,000 metric tons x $ 43,000 per kilogram = $ 3,440,000,000,000

While these numbers will be extremely rough, we still get an approximate value of $ 36 billion to $ 3.4 trillion. Using a factory on the moon or asteroid suddenly seems cheap.

NASA research results show that space-based solar power is "economically viable" if start-up costs range from $ 100-200 per kilogram. While prices continue to fall, thanks in part to SpaceX's reusable rockets, there is still a long way to go. However, this trend will follow Ray Kurzweil's Law of Accelerating Recoil, and launch prices will continue to decline from billions and millions to several hundred dollars.

Needless to say, the problem is not technology, but cost.

The future of solar energy

SBSP's ability to provide clean, reliable electricity to the planet 24/7 at a fraction of the cost of any other source is absolutely real. But it will take decades of investment, assembly, testing, and successful implementation before the system begins to recoup its initial investment.

Still, the right political climate is an essential component of promoting SBSP as a de facto source of energy.

Why do we need the energy of the sun?

Politics aside, with SBSP (or nuclear fusion) in the next decade, we could implement these scientific concepts:

  • Space elevators and space towers
  • Orbital rings - using space elevators to create a ring around the Earth instead of a space station for cheap cargo movement and space exploration
  • Dyson Spheres are giant shells that envelop an entire star and absorb all of its energy output
  • Matryoshka brains - Dyson's layered spheres to transform stars into massive computers using the energy released by all stars
  • Ring worlds are artificial planets using an entire star

Ilya Khel