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#1 2021-08-06 20:42:48

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

SPS Solar Power Satellite

For SpaceNut .... I couldn't believe this topic did not exist already.

I searched for SPS by itself (which you have indicated might not be long enough)

Then I searched for "solar" and "power" and "satellite" (without the quotes) and nothing came back.

Here is news that appears to be of sufficient quality and potential impact to justify it's own topic:

https://www.yahoo.com/finance/news/100m … 28769.html

Diagram showing how tiles like the one above could be joined together to form strips, then spacecraft, then arrays of spacecraft. Image Credits: Caltech

These will be small-scale tests (about six feet across), but the vision is for something rather larger. Bigger than anything currently in space, in fact.

"The final system is envisioned to consist of multiple deployable modules in close formation flight and operating in synchronization with one another," Hajimiri said. "Each module is several tens of meters on the side and the system can be built up by adding more modules over time."

The article at the link above reports on a funded research effort at Caltech.

The first test articles are due for launch in 2023.

What I like about what I understand from the article, is that the team has dropped almost all of the 1970's concepts for how SPS would be done.  if I understand the concept correctly, the Caltech concept is to deploy small panels that can "do it all", and then add more until the assembly amounts to something.

The original plan (as forum members know well) was to build a gigantic system that deliver nothing at all until it was finished.

(th)

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#2 2021-08-10 15:14:24

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

Re: SPS Solar Power Satellite

Louis has kindly provided an update that perfectly fits this new topic!

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#3 2021-08-10 20:17:33

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,750

Re: SPS Solar Power Satellite

Thats a test of beamed solar power in the link

I found these 2 topics

Solar Power Satellites to Power Human to Mars Mission

LOX - Ideal Solar Electric Propellent?

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#4 2023-01-06 20:58:51

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

Re: SPS Solar Power Satellite

Here's a report on a teeny tiny SPS test bed recently launched...

https://www.yahoo.com/news/why-solar-pa … 00886.html

The Hill
Could solar power work in space? Test aims to find out

Amy Thompson
Fri, January 6, 2023 at 9:09 AM EST
Editor’s note: This story has been updated to correct the headline. We regret the error.

Among the many space-bound satellites aboard the SpaceX rocket launched earlier this week was a small prototype designed to harvest the power of the sun.

Scientists are hoping to show that space-based solar power is more than a futuristic concept, and potentially the next big thing in clean energy.

Weighing in at just 110 pounds, the prototype satellite called the Space Solar Power Demonstrator (SSPD) is part of a larger effort to test out space-based solar power called the Space Solar Power Project (SSPP).

Built by engineers at CalTech, the demonstration mission blasted off into space on Tuesday morning. The team is hoping to see if the technology is capable of working in the harsh environment of space, and ultimately launching a constellation of solar panels that would form an orbital power station, beaming energy harvested from the sun back down to Earth.

Humanity has been harnessing the sun’s power since the advent of the first solar cells in 1880. Solar energy is clean, it’s cheap and we have an almost never-ending supply of it. Yet only about 5 percent of the world’s energy is supplied by the sun. That’s because solar panels are expensive and unreliable as a main energy source.

And they have historically been too big and bulky to launch into space — but that’s changing, along with the affordability of those satellite launches generally.

In 2015, SpaceX shook up the aerospace industry when the company proved that rockets could be reusable. To date, the company has launched 200 rockets and recovered 161 of them. This feat continues to drive down launch costs as more and more companies aim to make their rockets reusable.

On Tuesday, SpaceX launched SSPD as part of its Transporter-6 mission, a sort of cosmic Uber pool that allows many smaller satellites to share the cost of the rocket. This in turn enables more access to space.

Solar panels are designed to take energy from our star and convert it into energy we can use here on Earth to power our lives. However, there are some limitations: weather and the fact that the sun doesn’t shine at night. As such, the power we receive from these devices is not consistent.

But by moving solar power stations to space, we could produce electricity from solar power around the clock. That’s because the power would not be obscured by the day-night cycle or cloud cover, or affected by the changing seasons.

So what does a solar power station look like?

The SSPP team has developed one idea. To create its satellite, the engineers had to create a craft that was light enough for it to be scalable and cost-effective, while also being durable enough to withstand the harsh environment of space. It also had to be able to convert solar energy into energy that could be used on Earth. This called for the creation of new materials and technologies, resulting in the satellite we see today.

The SSPD is composed of three different experiments rolled into one. The Deployable on-Orbit ultraLight Composite Experiment (DOLCE) will test the mechanisms needed to deploy solar panels in orbit. Another experiment onboard, known as ALBA, will analyze 32 different types of photovoltaic (PV) cells to see which cells perform better in the harsh environment of outer space. Finally, the Microwave Array for Power-transfer Low-orbit Experiment (MAPLE) will evaluate an array of 32 different microwave transmitters.

The SSPP hopes its satellite will lead to the development of a constellation of modular spacecraft that collect sunlight, transform it into electricity, then wirelessly transmit that electricity over long distances wherever it is needed — including to places that currently have no access to reliable power.

John Mankins, a former NASA researcher, says that harvesting sunlight in space and delivering it wirelessly to Earth would be more feasible than one would think, noting that NASA has been exploring it for decades.

And he said recent studies have shown that a modular, mass-produced approach to building the necessary hardware would make it economical.

“Combine low-cost launches with modular technology, and suddenly the economics of space solar power become obvious,” he said.

Phil Metzger, a planetary scientist and former NASA researcher, said this technology could be game-changing not only to those who don’t have access to traditional power sources, but also for planetary missions and other activities in low-Earth orbit.

“We should be developing off-planet mining and manufacturing which will make space-based solar power even more economic and scalable,” Metzger said.

“The cost of building things in space drops faster than launch costs and the impact of fossil fuels on the environment will continue to go up, so space-based solar power will become economical.”

Mankins says that one of the biggest hurdles — after cost — will be to ensure that we can beam as much of the power collected back to Earth as possible and that it ends up where we want it. Earth’s atmosphere can prove tricky, but the more this technology is tested, the more refined it will become.

To that end, CalTech isn’t the only enterprise tossing around the idea of space-based solar power. The European Space Agency, Japan and China are also conducting studies into its feasibility.

“Space-based solar power would be an important step towards carbon neutrality and energy independence, not only for Europe, but for everyone,” said Josef Aschbacher, director general of the European Space Agency. “Our studies have shown that.”

The U.S. military also recently conducted its own solar power experiment in space, contained inside the X-37B spaceplane, which evaluated the sunlight-to-microwave conversion process. SSPD will help take it one step further.

(th)

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#5 2023-01-07 14:28:44

RobertDyck
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From: Winnipeg, Canada
Registered: 2002-08-20
Posts: 7,782
Website

Re: SPS Solar Power Satellite

Has anyone successfully beamed power over great distance? I haven't read any tests lately. The tests I did read about only achieved an efficiency of 30% over a few miles. The advantage to solar power satellites is they receive sunlight 24/7. Earth's atmosphere blocks some light due to water and oxygen, clouds block more, and of course there's no sunlight at night. But if you only get 30% sunlight and power cables deliver that power with 100% efficiency, as opposed to a satellite that gets 100% sunlight and beamed power only receives 30%, then the result is the same. Setting up a solar power system on Earth requires a truck to deliver parts, while orbit requires a launch vehicle. Repairs on Earth require a technician in jeans in normal clothing while space requires a spacecraft on a launch vehicle and spacesuit. Cost to set up a system on Earth is orders of magnitude cheaper.

Then there's safety. A multi-megawatt microwave beam better have perfect aim. If it misses and hits the nearby city, it could cook residents. Even with perfect aim, an aircraft flying through the beam would be extremely dangerous.

I have argued for decentralization. Instead of one big power utility, each house can generate its own power. Solar power roof and helical windmills in the back yard. Giant windmills for power utilities use propellers because they work more efficiently with consistent wind direction. However, low to the ground in a suburb with multiple building causing wind to swirl around those buildings, wind could change direct to any of the 4 points of the compass from one second to the next. Helical windmills work with wind coming from north, east, south, west, or even an up draft. So helical windmills are more efficient for a single house. Besides there's a German manufacturer that makes helical windmills that look like a piece of art. When weather is overcast so less sunlight for the solar panels, it tends to be windy. When skies are clear with bright sunlight, there's no wind. So solar and wind complement each other. Combine high efficiency photovoltaic panels that completely cover the house roof, with a few helical windmills in the back yard, geothermal heat pump, and deep-cycle batteries in the basement. Result is a house that's 100% energy independent during worst case weather, even in northern locations like Winnipeg, where I live. Of course Winnipeg is just 60 miles north of the border with North Dakota, so this would work in North Dakota, Minnesota, and Montana as well.

I have also suggested mounting the photovoltaic panels on a copper manifold. The matte black colour of high efficiency photovoltaic panels will convert to heat any energy not converted to electricity. A copper manifold with smooth top surface, but bottom sheet has channels pressed into it for water flow. Add silver solder between channels, braze the outer edges, then bake the manifold in an oven hot enough to melt the solder. The result will preheat water destined for the water heater, reducing power consumption for hot water. Mount the photovoltaic cells using the same thermal compound that computers use to mount the CPU to a metal heat sink. Add thermal insulation to the back of the manifold. This makes the solar panel dual mode: photovoltaic and thermal. But it also ensures the photovoltaic cells do not overheat. That's how solar panels fail, so the manifold will extend the life of the solar panel.

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#6 2023-01-07 19:25:19

SpaceNut
Administrator
From: New Hampshire
Registered: 2004-07-22
Posts: 28,750

Re: SPS Solar Power Satellite

Caltech news release

DOLCE (Deployable on-Orbit ultraLight Composite Experiment): A structure measuring 6 feet by 6 feet that demonstrates the architecture, packaging scheme and deployment mechanisms of the modular spacecraft that would eventually make up a kilometer-scale constellation forming a power station;
ALBA: A collection of 32 different types of photovoltaic (PV) cells, to enable an assessment of the types of cells that are the most effective in the punishing environment of space;
MAPLE (Microwave Array for Power-transfer Low-orbit Experiment): An array of flexible lightweight microwave power transmitters with precise timing control focusing the power selectively on two different receivers to demonstrate wireless power transmission at distance in space.

DOLCE_unfolding.max-500x500.gif

more details on the project
https://www.spacesolar.caltech.edu/

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#8 2023-01-17 19:55:28

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

Re: SPS Solar Power Satellite

Here's another view of the satellite reported in SpaceNut post #7

http://newmars.com/forums/viewtopic.php?id=10413

SpaceX Rocket Sends Solar Power Prototype Into Orbit
Editor OilPrice.com
Tue, January 17, 2023 at 1:00 PM EST
The Caltech Space Solar Power Project (SSPP) prototype launched into orbit, dubbed the Space Solar Power Demonstrator (SSPD), will test several key components of an ambitious plan to harvest solar power in space and beam the energy back to Earth.

Space solar power provides a way to tap into the practically unlimited supply of solar energy in outer space, where the energy is constantly available without being subjected to the cycles of day and night, seasons, and cloud cover.

For more lots more images, gifs and video, here are the links: 1st, Cal Tech’s press release. Then 2nd, the project web site.

The launch represents a major milestone in the project and promises to make what was once science fiction a reality. When fully realized, SSPP will deploy a constellation of modular spacecraft that collect sunlight, transform it into electricity, then wirelessly transmit that electricity over long distances wherever it is needed – including to places that currently have no access to reliable power.

A Momentus Vigoride spacecraft carried aboard a SpaceX rocket on the Transporter-6 mission carried the 50-kilogram SSPD to space. It consists of three main experiments, each tasked with testing a different key technology of the project:

DOLCE (Deployable on-Orbit ultraLight Composite Experiment): A structure measuring 6 feet by 6 feet that demonstrates the architecture, packaging scheme and deployment mechanisms of the modular spacecraft that would eventually make up a kilometer-scale constellation forming a power station;

ALBA: A collection of 32 different types of photovoltaic (PV) cells, to enable an assessment of the types of cells that are the most effective in the punishing environment of space;

MAPLE (Microwave Array for Power-transfer Low-orbit Experiment): An array of flexible lightweight microwave power transmitters with precise timing control focusing the power selectively on two different receivers to demonstrate wireless power transmission at distance in space.

An additional fourth component of SSPD is a box of electronics that interfaces with the Vigoride computer and controls the three experiments.

SSPP got its start in 2011 after philanthropist Donald Bren, chairman of Irvine Company and a lifetime member of the Caltech Board of Trustees, learned about the potential for space-based solar energy manufacturing in an article in the magazine Popular Science.

Intrigued by the potential for space solar power, Bren approached Caltech’s then-president Jean-Lou Chameau to discuss the creation of a space-based solar power research project. In 2013, Bren and his wife, Brigitte Bren, a Caltech trustee, agreed to make the donation to fund the project. The first of the donations (which will eventually exceed $100 million) was made that year through the Donald Bren Foundation, and the research began.

Bren said, “For many years, I’ve dreamed about how space-based solar power could solve some of humanity’s most urgent challenges. Today, I’m thrilled to be supporting Caltech’s brilliant scientists as they race to make that dream a reality.”

The rocket took approximately 10 minutes to reach its desired altitude. The Momentus spacecraft was deployed from the rocket into orbit. The Caltech team on Earth plans to start running their experiments on the SSPD within a few weeks of the launch.

Some elements of the test will be conducted quickly. “We plan to command the deployment of DOLCE within days of getting access to SSPD from Momentus. We should know right away if DOLCE works,” said Sergio Pellegrino, Caltech’s Joyce and Kent Kresa Professor of Aerospace and Professor of Civil Engineering and co-director of SSPP. Pellegrino is also a senior research scientist at JPL, which Caltech manages for NASA.

Other elements will require more time. The collection of photovoltaics will need up to six months of testing to give new insights into what types of photovoltaic technology will be best for this application. MAPLE involves a series of experiments, from an initial function verification to an evaluation of the performance of the system under different environments over time.

Meanwhile, two cameras on deployable booms mounted on DOLCE and additional cameras on the electronics box will monitor the experiment’s progress, and stream a feed back down to Earth. The SSPP team hopes that they will have a full assessment of the SSPD’s performance within a few months of the launch.

Numerous challenges remain: nothing about conducting an experiment in space – from the launch to the deployment of the spacecraft to the operation of the SSPD – is guaranteed. But regardless of what happens, the sheer ability to create a space-worthy prototype represents a significant achievement by the SSPP team.

Ali Hajimiri, Caltech’s Bren Professor of Electrical Engineering and Medical Engineering and co-director of SSPP said, “No matter what happens, this prototype is a major step forward. It works here on Earth, and has passed the rigorous steps required of anything launched into space. There are still many risks, but having gone through the whole process has taught us valuable lessons. We believe the space experiments will provide us with plenty of additional useful information that will guide the project as we continue to move forward.”

Although solar cells have existed on Earth since the late 1800s and currently generate about 4 percent of the world’s electricity (in addition to powering the International Space Station), everything about solar power generation and transmission needed to be rethought for use on a large scale in space.

Solar panels are bulky and heavy, making them expensive to launch, and they need extensive wiring to transmit power. To overcome these challenges, the SSPP team has had to envision and create new technologies, architectures, materials, and structures for a system that is capable of the practical realization of space solar power, while being light enough to be cost-effective for bulk deployment in space, and strong enough to withstand the punishing space environment.

Pellegrino commented, “DOLCE demonstrates a new architecture for solar-powered spacecraft and phased antenna arrays. It exploits the latest generation of ultrathin composite materials to achieve unprecedented packaging efficiency and flexibility. With the further advances that we have already started to work on, we anticipate applications to a variety of future space missions.”

Hajimiri noted, “The entire flexible MAPLE array, as well as its core wireless power transfer electronic chips and transmitting elements, have been designed from scratch. This wasn’t made from items you can buy because they didn’t even exist. This fundamental rethinking of the system from the ground up is essential to realize scalable solutions for SSPP.”

The entire set of three prototypes within the SSPD was envisioned, designed, built, and tested by a team of about 35 individuals. “This was accomplished with a smaller team and significantly fewer resources than what would be available in an industrial, rather than academic, setting. The highly talented team of individuals on our team has made it possible to achieve this,” Hajimiri added.

Those individuals, however – a collection of graduate students, postdocs, and research scientists – now represent the cutting edge in the burgeoning space solar power field.

“We’re creating the next generation of space engineers,” said SSPP researcher Harry A. Atwater, Caltech’s Otis Booth Leadership Chair of the Division of Engineering and Applied Science and the Howard Hughes Professor of Applied Physics and Materials Science, and director of the Liquid Sunlight Alliance, a research institute dedicated to using sunlight to make liquid products that could be used for industrial chemicals, fuels, and building materials or products.

Success or failure from the three testbeds will be measured in a variety of ways. The most important test for DOLCE is that the structure completely deploys from its folded-up configuration into its open configuration. For ALBA, a successful test will provide an assessment of which photovoltaic cells operate with maximum efficiency and resiliency. MAPLE’s goal is to demonstrate selective free-space power transmission to different specific targets on demand.

“Many times, we asked colleagues at JPL and in the Southern California space industry for advice about the design and test procedures that are used to develop successful missions. We tried to reduce the risk of failure, even though the development of entirely new technologies is inherently a risky process,” said Pellegrino.

SSPP aims to ultimately produce a global supply of affordable, renewable, clean energy. More about SSPP can be found on the program’s website: https://www.spacesolar.caltech.edu/

***

Your humble writer says this is a huge success right now. And will add a thanks to a privateer investor, Donald Bren, his wife, Brigitte Bren, and his foundation. Sometimes great wealth gives back in a great way.

There isn’t a failure possible in this. The test equipment is in orbit and the information, every byte, is a success. The question that exists is just how fully realized will the tests and experiments get? One hopes far enough to encourage more investment and further research.

By Brian Westenhaus via New Energy and Fuel

More Top Reads From Oilprice.com:

(th)

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#9 2023-12-18 08:09:14

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

Re: SPS Solar Power Satellite

This topic has been quiet for nearly a year ....

A post by kbd512 in another topic reminded me of SPS, so I asked fluxbb if we had a topic ...

The variation I would like to offer today is of the Sun Synchronous Orbit category for placement of SPS devices

The advantage is that the distance to be covered by microwaves is less.  According to Wikipedia, such satellites orbit in the range of 600-800 km (370-500 miles).

The disadvantage is that ground stations must be located along the path, and the energy supply is necessarily limited to about an hour per day.  However, during that hour, the energy supply would be reliable.

I think this idea has come up before in the forum, but in a topic with an unrelated title.

(th)

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#10 2023-12-28 12:49:32

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

Re: SPS Solar Power Satellite

A relative sent this update on the Caltech SPS experiments ...

https://www.cnn.com/2023/12/27/climate/ … id=ios_app

World / Climate
This wild, futuristic space plan could help save the world. But some say it’s too far-fetched
By Laura Paddison, CNN
9 minute read
Updated 8:21 AM EST, Wed December 27, 2023

An illustration of the UK-designed CASSIOPeiA solar power satellite. Space-based solar power involves harvesting sunlight from Earth orbit then beaming it down to the surface where it is needed.

Space Solar
CNN

Ali Hajimiri has spent a decade researching how to put solar panels in space and beam the energy down to Earth. Yet when the Caltech electrical engineering professor talks about his work, people always have three questions, usually in this order: Why not just put solar panels on Earth? Are you going fry birds in the sky? Are you building a Death Star?

Hajmiri jokes he plans to have the answers printed on a card. “I’m going to have it in my wallet to show people,” he said.

Originally a space solar skeptic, Hajimiri’s interest was piqued when he started looking more closely at the idea. “On average, you get about eight times more power in space” compared with solar on Earth, he told CNN. The beam won’t kill animals either. And as for the Death Star? The beam won’t be powerful enough to be weaponized, he added.


This year, Hajimiri and his team made a step towards making space-based solar a reality.

In January, they launched Maple, a 30-centimeter-long space solar prototype equipped with flexible, lightweight transmitters. The aim was to harvest energy from the sun and transfer it wirelessly in space, which they did, managing to light up a pair of LEDs.

But the “stretch goal” was to see if Maple could also beam down detectable energy to Earth. In May, the team decided to launch a “dry run” to see what would happen. On a rooftop on the Caltech campus in Pasadena, California, Hajimiri and the other scientists were able to pick up Maple’s signal.

A worker cleans solar panels at a new energy base of Tengger Desert on December 9, 2023 in Zhongwei, Ningxia Hui Autonomous Region of China.
After a terrible year of climate news, here are 5 reasons to feel positive

The amount of energy they detected was tiny, too small to be useful, but they had succeeded in wirelessly beaming down power from space. “It was only after the fact that it dawned on us a little bit that, OK, well, this was something very special,” said Hajimiri.

Space-based solar may sound a wild, futuristic idea, but it is not new. As far back as 1941, it was described in a short story by science fiction writer Isaac Asimov. In the decades since, countries including the US, China and Japan have explored the idea — but for years it was written off. “The economics were just way out,” said Martin Soltau, CEO of the UK-based company Space Solar.

That may now be changing as the cost of launching satellites falls sharply, solar and robotics technology advances swiftly, and the need for abundant clean energy to replace planet-heating fossil fuels becomes more urgent.

There’s a “nexus of different technologies coming together right now just when we need it,” said Craig Underwood, emeritus professor of spacecraft engineering at the University of Surrey in the UK.

The problem is, these technologies would need to be deployed at a scale unlike anything ever done before.

What is space-based solar?

At its heart, space-based solar is a fairly straightforward concept. Humans could harness the enormous power of the sun in space, where it’s available constantly — unaffected by bad weather, cloud cover, nighttime or the seasons — and beam it to Earth.

There are different concepts, but it would work roughly like this: huge solar power satellites, each more than a mile long in diameter, would be sent into a very high orbit.

Because of the colossal size of these structures, they would be made up of hundreds of thousands of much smaller, mass-manufactured modules, “like lego bricks,” Soltau told CNN, which would be assembled in space by autonomous robotic assembly machines.

The satellite’s solar cells would capture the sun’s energy, convert it into microwaves and beam it down to Earth wirelessly via a very large transmitter, able to hit specific points on the ground with precision.

With the International Space Station and the tallest building in the world, the Burj Khalifa, shown for scale, this illustration demonstrates how massive the CASSEioPia array would be.

CNN
The microwaves, which can easily travel through clouds and bad weather, would be directed to a receiving antenna (or “rectenna”) on Earth made of mesh — “think of a sort of fishing net hung on bamboo poles,” Soltau said — where the microwaves would be converted back into electricity and fed into the grid.

Illustration - Space-Based Solar Power involves transforming solar power into electricity via photovoltaic cells in geostationary orbit around Earth. The power is then transmitted wirelessly in the form of microwaves at 2.45 GHz to dedicated receiver stations on Earth, called 'rectennas', which convert the energy back into electricity and feed it into the local grid.

Power would be transmitted wirelessly in the form of microwaves to dedicated receiver stations on Earth, called "rectennas," which convert the energy back into electricity and feed it into the local grid.
ESA
The rectenna, approximately 6 kilometers (3.7 miles) in diameter, could be built on land or offshore. And because these mesh structures would be nearly transparent, the idea is the land underneath them could be used for solar panels, farms or other activities.

A single space solar satellite could deliver up to 2 gigawatts of power, roughly the same amount as two average nuclear power plants in the US.

An idea whose time has come?

There’s “nothing science fiction” about space-based solar, Underwood, the UK professor, told CNN. The technology is mature, he said. “The big stumbling block has been simply the sheer cost of putting a power station into orbit.”

Over the last decade, that has begun to change as companies such as SpaceX and Blue Origin started developing reusable rockets. Today’s launch costs at around $1,500 per kilogram are about 30 times less than in the Space Shuttle era of the early 1980s.

And while launching thousands of tons of material into space sounds like it would have a huge carbon footprint, space solar would likely have a footprint at least comparable to terrestrial solar per unit of energy, if not a smaller, because of its increased efficiency as sunlight is available nearly constantly, said Mamatha Maheshwarappa, payload systems lead at UK Space Agency.

Some experts go further. Underwood said the carbon footprint of space-based solar would be around half that of a terrestrial solar farm producing the same power, even with the rocket launch.

But that doesn’t mean space-based solar should replace terrestrial renewables, he added. The idea is that it could provide “baseload” power that can be called upon around the clock to fill in the gaps when the wind doesn’t blow and the sun doesn’t shine on Earth. Currently, baseload power tends to be provided by power plants running on fossil fuels or nuclear energy, which are able to operate with little interruption.

The power would be “very portable,” said Peter Garretson, a senior fellow in defense studies at the American Foreign Policy Council. It could be beamed from space to the top of Europe, for example, and then to the bottom of Africa.

Many advocates point to the potential it could offer developing countries with deep energy needs but a lack of infrastructure. All they would need is a rectenna. “It will provide real democratization of abundant affordable energy,” Soltau said.

Space-based solar could also help power remote Arctic towns and villages that lie in almost complete darkness for months each year, and could beam power to support communities experiencing outages during climate disasters or conflict.

The challenges

There is still a huge gulf between concept and commercialization.

We know how to build a satellite, and we know how to build a solar array, the UK Space Agency’s Maheshwarappa said. “What we don’t know is how to build something this big in space.”

She gives the example of the Burj Khalifa in Dubai, the tallest building in the world, which stands at around 830 meters, or roughly 2,700 feet. “The structures that we are talking about are twice that,” Maheshwarappa told CNN. “So we have not even built something this big on the ground, let alone in space.”

Then there’s regulating this new energy system, to ensure the satellites are built sustainably, there’s no debris risk, and they have an end-of-life plan, as well as to determine where rectenna sites should be located.

Public buy-in could be another huge obstacle, Maheshwarappa said. There can be an instinctive fear when it comes to beaming power from space.

But such fears are unfounded, according to some experts. The energy density at the center of the rectenna would be about a quarter of the midday sun. “It is no different than standing in front of a heat lamp,” Hajimiri said.

And to build a satellite capable of doing harm to people, it would have to be many times bigger than the concepts currently being developed, Hajimiri said. “Anyone who tries to start building that, everyone else would know.”

That doesn’t mean questions shouldn’t be asked, he said. The idea is “to benefit humanity, and if it doesn’t, there’s no point.”

An artist’s impression of what a solar power satellite could look like
ESA

For some, however, the whole concept of space-based solar is misplaced.

Amory Lovins, a physicist and adjunct professor at Stanford University, said the world would be far better focusing on terrestrial renewables. The extra energy in space and the ability to harvest it nearly 24 hours a day “is not valuable enough to pay for the cost to collect it and beaming the energy down,” he told CNN.

For Lovins, promises that the system would be a great source of baseload power don’t hold up either. There are techniques to match energy demand to supply, rather than the other way around, without consumers even noticing. Having a huge power source that is producing all the time is “undesirably inflexible,” he said.

“Why spend money on something that has no chance of a business case if you succeeded, whose need will have been met before you could build it and whose most optimistic future cost estimates are the same as the current price of terrestrial solar power plus batteries?” he asked.

The future
But governments and companies around the world believe there is huge promise in space-based solar to help meet burgeoning demand for abundant, clean energy and tackle the climate crisis.

A development program able to demonstrate proof of concept is about five or six years away, Soltau said. It will then take another five or six years to industrialize and scale up the gigawatt-scale system to be fully operational.

Strong government support will be key, he said. “It’s an ambitious thing to create a brand new energy technology.”

In the US, the Air Force Research Laboratory has plans to launch a small demonstrator called Arachne in 2025, and the US Naval Research Laboratory launched a module in May 2020 aboard an orbital test vehicle, to test solar hardware in space conditions.

The China Academy of Space Technology, a spacecraft designer and manufacturer, is aiming to send a solar satellite into low orbit in 2028 and into high orbit by 2030, according to a 2022 South China Morning News report.

Illustration - Space-Based Solar Power involves harvesting sunlight from Earth orbit then beaming it down to the surface where it is needed.
An illustration of what a space solar satellite could look like. Governments around te world are investing in programs to research and develop the concept.

Andreas Treuer/ESA
There’s been a burst of activity from the UK government. It commissioned an independent study which reported in 2021 that space-based solar was technically feasible, highlighting designs such as the UK-led CASSIOPeiA, a satellite 1.7 kilometers (1 mile) in diameter that aims to deliver 2 gigawatts of power. In June this year, the government announced nearly $5.5 million in funding to universities and tech companies “to drive forward innovation” in the space-based solar sector.

And Europe has its Solaris program, to establish the technical and political viability of space-based solar, in preparation for a possible decision in 2025 to launch a full development program.

“Obviously, before you build something, everything is speculation,” said Garretson, “but there are strong reasons to think that this might actually be economically possible and viable.”

Back in California, Hajimiri and his team have spent the last six months stress testing their prototype to extract data to feed into the next generation of design.

Hajimiri’s ultimate vision is series of lightweight, flexible sails, that can be rolled up, launched and unfurled in space, with billions of elements working in perfect synchronization to send energy where it is needed

He views their project as “part of this long chain of people who build upon each other’s work and help each other,” he said. “So we are taking an important step, perhaps, but it is not the last step.”

(th)

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#11 2024-03-04 12:19:43

tahanson43206
Moderator
Registered: 2018-04-27
Posts: 16,755

Re: SPS Solar Power Satellite

The Caltech initiative is mentioned in the report that Mars_B4_Moon posted recently...

https://newmars.com/forums/viewtopic.ph … 26#p220026

The bottom line that jumped out at me was that NASA does NOT want this assignment.

I think it would be better suited to the Military or perhaps DOE.

The assumptions cited in the article are downbeat (as I understand them).

The US Military could power entire island bases from SPS, and not have to import a barrel of oil.

(th)

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