Showing posts with label Spaceenergy. Show all posts
Showing posts with label Spaceenergy. Show all posts

16 September 2010

Why Not Space Solar Power?

Spacenews has published an OpEd by Don Flournoy on Space Solar Power
Why Not Space Solar Power?
Mon, 13 September, 2010
By Don Flournoy
The 2010 U.S. National Space Policy, which supports a robust and competitive commercial space sector, is good news for those of us working to design and launch the new types of satellites that will collect solar energy in space and deliver it to Earth as a nonpolluting source of electrical power.
Among the goals of President Barack Obama’s National Space Policy is expansion of international cooperation on mutually beneficial space activities to “broaden and extend the benefits of space” and “further the peaceful use of space.”
As members of the National Space Society, the Society of Satellite Professionals International and the Space Energy Group, we believe space, as a shared resource, can best be explored and developed by a partnership of nations and businesses working together.
Since acquiring clean and abundant energy is a common requirement for economic growth and an eventual necessity for the health of all societies, harvesting space solar power is a logical human endeavor when the high frontier is precisely where energy is most plentiful. But achieving success doing large-scale commercial innovation in outer space requires long-range planning, pooling of financial resources, sharing of knowledge and expertise, and the careful framing of a way forward that will earn and sustain the public trust.
In naming the CEOs who will serve on his new advisory board on trade issues, Obama noted in July that the U.S. is on track to double exports in the next five years, and he pointed to some of the ways the American economy is being repositioned to better compete abroad. When adding that announcement to the outcomes of the June summit of the Group of 20 major industrial countries in Canada and recent federal policy statements intimating that (certain) export controls will be relaxed and cooperation in space will be encouraged, it would appear that the U.S. could be entering a new era of openness for international business.
To this end, we would like to see some greater leadership and support given to space solar power development by NASA and the U.S. departments of Energy and Commerce. A helpful first step would be a U.S.-led space solar power feasibility study to which all interested nations are invited to contribute.
In the context of the U.S. National Space Policy, such a feasibility study could lead the way in assessing and promoting “appropriate cost and risk sharing among participating nations in international partnerships.” It would demonstrate U.S. “tangible leadership in space,” leveraging the capabilities of allies while assuring continuing adherence to the U.N. Treaty on Exploration and Use of Outer Space — now signed by 125 states, including China and India — that dictates “nuclear weapons and other weapons of mass destruction” shall not be placed in outer space.
At the International Space Development Conference held in Chicago in May, multiple nations participated in a National Space Society-initiated Solar Power Symposium to examine in depth opportunities and challenges for energy generation in near space. Former Indian President A.P.J. Abdul Kalam, scientist, aeronautical engineer and proponent of space solar power, addressing the symposium via videoconference, spoke to the need for international cooperation in space. He proposed a multilateral global initiative that could map out for us what needs to be done to bring space solar power to operational reality.
From our perspective, space solar power is a meaningful science, engineering and commercial challenge that deserves our attention and investment. In the wake of the Gulf of Mexico oil disaster, we think it is time for the U.S. to put space solar power on our national energy agenda. At the same time, we must seek opportunities to learn from and participate with Canada, China, India, Japan, the European Union and others taking their first tentative steps to bring space solar energy to Earth.
In a June Times of India commentary on strategic international diplomacy, U.S. Sen. John Kerry expressed support for a partnership with India that would include “the quest for new technologies and fresh ideas for economically viable ways to speed the shift to renewable energy sources.”
We believe that within the mainstream of global science, engineering and environmental management there are game-changing ideas and technologies that await testing. It is time to see some space solar power demonstration projects. Of all the possible alternative energy sources on the near horizon, we believe space solar power is our best chance for addressing the worldwide challenges of climate change, renewable energy and continued economic growth.
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Don Flournoy is a professor and editor of the Online Journal of Space Communication (www.spacejournal.org) at Ohio University. This article also reflects the opinions of Robert Bell of the Society of Satellite Professionals International, Mark Hopkins of the National Space Society, Stephan Tennsel of Space Energy AG, and Feng Hsu of the Space Energy Group.

More news and blog entries on the Indo-US SBSP proposal:

India-US space-based solar power plan could solve major energy issues - study
(ADPnews) - Sep 14, 2010 - A space-based solar power (SBSP) programme developed by India and the US could solve the energy security and climate change issues, according to a report by US Air Force lieutenant colonel Peter Garretson.

Garretson, who is on a sabbatical as an international fellow at the institute for defence studies and analyses in New Delhi, considers that the two countries should conduct a feasibility analysis on such a programme, whose aim will be to replace fossil fuel energy with SBSP by 2025. However, in order to work on such a plan, India should first sign the Missile Technology Control Regime (MTCR) document, which the country declined to do earlier, deeming it discriminatory.

In his report, Garretson has included a three-phase plan, which starts with an initial five-year programme costing USD 10 million to USD 30 million for the development of contributing technologies and competent workforce. It is followed by a USD-10-billion investment in the construction of a sub-scale space solar power system over a 10-year period. The concluding stage envisages the establishment of an Indian-US consortium to face energy security and carbon mitigation issues.

Such a SBSP programme could be managed by the US Department of State's Office of Ocean Environment and Science and the Prime Minister's Council on Climate Change in India, according to Garretson's report.

Making the Case An Indo-USA Space-Based Solar Power Programme
By Bill Moore
I had a rude awakening this evening. What began as a casual journey into India's space programme -- the reasons will be apparent momentarily -- ended with the sobering realization that along with the sub-continent's explosive economic growth and the rise of the middle class, also comes the apparent need to flex its political muscles militarily in the form of nuclear submarines -- the first launched last year with more on order -- tactical transport aircraft jointly developed with the Russians, and even their own armada of aircraft carriers. And then there's their plan to send men to the moon by 2016.
I've been reading Peter Garretson's 2009 research paper for Indian Defense Studies and Analysis entitled, "Sky's No Limit: Space-based Solar Power, The Next Major Step in the Indo-US Strategic Partnership?" It is a heavily footnoted document of some 174 pages and six appendices. In it, Garretson makes the case that the next step in the United States and India's strategic relationship should be establishment of a "big policy" programme (I'll use the British spelling) to put solar power generation systems in earth orbit. While the paper doesn't go into the technological issues, it does focus on the policy implementation barriers of such a collaboration.
Of course, as a parochial American with only a passing knowledge of Indian food -- which I love -- and Bollywood movies -- which I also find highly entertaining as long as I can keep up with the English subtitles -- I asked myself was India, in fact, technologically capable of making a meaningful contribution to such a programme? Sure, their Chandrayaan-1 moon mission was an impressive achievement, discovering evidence for water, but could they really be expected to lift millions of pounds of components into geosynchronous orbit to build hundreds, even thousands of 5 km width solar arrays?
The answer is, in fact, yes. The Indian Space Research Organization (ISRO) has a series of launch vehicles; the largest being the GSLV III, now in development, will be capable of lifting 4,500kg (10,000 lbs) of payload into geosynchronous transfer orbit, putting it on a par with competing American and French launch vehicles. Importantly, it appears they can do it rather cheaply. The Chandrayaan-1 mission in 2008 cost just US$79 million.
And why should India or the United States even consider such an initiative, either alone or in partnership? Besides the fact that the Japanese are spending money on their own SBSP program and plan to have a 1 GW platform in orbit by 2030, you mean? Garretson takes pains to explain that it may, in fact, be the only choice the planet has to provide humanity with the clean, pollution-free, electric power it needs, especially in populous nations like India where 50-60% of it citizens will be living in cities by 2039. At present, India, as well as the United States, depends on coal-fired power plants for half of its electricl power generation capacity. It is estimated India's coal reserves will last 80 years, but Garretson points out that at a projected growth rate of just 5 percent a year, those reserves will be exhausted in 45 years; and this doesn't even address the critical problem of water shortages in India, water on which thermoelectric power plants, both fossil fuel and nuclear, are dependent.
So, why not simply build vast solar farms in India's Thar Desert, which stretches across the northwestern states of Rajasthan and Gujara, and occupies more than 2.5 million square kilometers? Efficiency and intermittency are why. All earth-bound solar installations suffer from the same problem: the sun shines on them only part of the day and the atmosphere -- and its associated weather -- reduce their efficiency even further. Space-based solar stations can provide solar power, transmitted back to earth in the form of low-frequency radio waves, 24 hours a day at the sun's maximum power rate of 1330+ watts per meter. At least that's the theory. Those same radio waves have to penetrate the atmosphere and its weather, be converted by circular farms of specially-designed rectenna's with 80 percent-plus efficiency back to electric power and then distributed to urban centers. In a footnote(14) on page 23 of Garretson's paper, it is estimated that only two percent of the energy transmitted down to earth would be lost in the form of heat, and that the type of radio wave being considered will have no or virtually no impact on humans or animals. He notes that, "NASA, DOE, and EPA have conducted extensive experiments to assess if there were ill effects to biological life or the upper atmosphere due to such beams. None of the studies conducted so far suggest that there is any significant detrimental effect."
Assuming all other objections and technical issues can be resolved, what's the potential of SBSP and what's its cost? Citing studies by James Snead and Harry Stine (footnote 10, page 22) Garretson estimates, "the exploitable energy in orbit exceeds not just the electrical demand of the planet today, but the total energy needs of a fully developed planet with over 10 billion people." As for the question of cost, Sky's No Limit estimates that the world currently spends $6 trillion on energy of all forms annually. Most of that energy produces highly undesirably pollution and climate change, which SBSP would not. Further, SBSP would make no environmental demands on the planet's freshwater supply.
The idea would certainly seem to have merit. Imagine an EV world where all our motor vehicles are powered by electricity transmitted from thousands of orbiting solar stations. However, moving such a project from the dreamer's stage to the schemer's stage will prove the first major obstacle to overcome. If nothing else, Sky's No Limit makes thought-provoking reading. It certainly opened my eyes to the state of technological development taking place in India beyond Tata Nanos, Revas and Hero electric bicycles.

New Space Energy Newsletter:
http://www.spaceenergy.com/AnnouncementRetrieve.aspx?ID=56424
It reviews the IDSA-CFR paper on Indo-US Space Solar Power cooperation.


Introduction of Peter Garretson´s New SBSP Paper: "Sky´s No Limit"

Hot off the press, Space Energy is proud to announce the publication of the latest paper from one of the original SBSP `caballeros´, Peter Garretson, entitled “Sky’s No Limit: Space-Based Solar Power, the Next Major Step in the Indo-US Strategic Partnership?”

Referred to as IDSA Occasional Paper No. 9, this paper provides a policymaker's overview of a highly scalable, revolutionary, renewable energy technology, Space-Based Solar Power (SBSP), and evaluates its utility within the context of the Indo-US strategic partnership.  After providing an overview of the concept and its significance to the compelling problems of sustainable growth, economic development, energy security and climate change, it evaluates the utility of the concept in the context of respective Indian and US political and energy-climate trajectories.  The paper concludes that a bilateral initiative to develop Space-Based Solar Power is highly consistent with the objectives of the Indo-US strategic partnership, and ultimately recommends an actionable three-tiered programme to realize its potential.

Peter Garretson's credentials are unparalleled.  He was a Council on Foreign Relations (CFR), International Fellow in India, and a Visiting Fellow at the Institute for Defence Studies and Analyses (IDSA) in New Delhi.  He is an active duty Air Force officer on sabbatical as an Air Force Fellow.  He was previously the Chief of Future Science and Technology Exploration for Headquarters Air Force, Directorate of Strategic Plans and Programs, and is a former DARPA Service Chiefs’ Intern, and former Los Alamos National Laboratory (LANL) Service Academy Research Associate.  He is a published author on Space Grand Strategy, and is a recipient of the National Space Society’s (NSS) Space Pioneer Award.

Peter Garretson´s past IDSA papers can be found here.

A presentation made by the author of the IDSA-CFR Report can be downloaded from here:

19 June 2010

Space Solar Update

Outstanding Video of HLV Deploying Prototype Space Solar Power Satellite:
http://www.frassanito2.com/SPS/

New SpaceEnergy newsletter:
http://spaceenergy.com/AnnouncementRetrieve.aspx?ID=50293


First Solar Sail Spacecraft Photographed (Japanese Deepspace Probe Ikaros "kitecraft" propelled only by sunlight)
http://www.space.com/missionlaunches/worlds-first-solar-sail-photo-japan-100618.html

Funny Episode of the Daily Show on Energy Independence:
http://www.thedailyshow.com/watch/wed-june-16-2010/an-energy-independent-future

05 November 2009

Space Based Solar Power on TED

Peter Sage from SpaceEnergy lays out the case for Space Based Solar Power




http://spacemovement.blogspot.com/2009/11/peter-sage-speaks-on-ssp-at-ted.html
http://www.facebook.com/pages/Space-Solar-Power/95417219921
http://www.youtube.com/watch?v=3_m6tlF901g&feature=player_embedded

Also, Space Solar Power made #1 of WSJ's top "Five Technologies that Could Change Everything":
From: http://online.wsj.com/article/SB10001424052748703746604574461342682276898.html

SPACE-BASED SOLAR POWER

For more than three decades, visionaries have imagined tapping solar power where the sun always shines—in space. If we could place giant solar panels in orbit around the Earth, and beam even a fraction of the available energy back to Earth, they could deliver nonstop electricity to any place on the planet.



Source: New Scientist
Sunlight is reflected off giant orbiting mirrors to an array of photovoltaic cells; the light is converted to electricity and then changed into microwaves, which are beamed to earth. Ground-based antennas capture the microwave energy and convert it back to electricity, which is sent to the grid.

The technology may sound like science fiction, but it's simple: Solar panels in orbit about 22,000 miles up beam energy in the form of microwaves to earth, where it's turned into electricity and plugged into the grid. (The low-powered beams are considered safe.) A ground receiving station a mile in diameter could deliver about 1,000 megawatts—enough to power on average about 1,000 U.S. homes.

The cost of sending solar collectors into space is the biggest obstacle, so it's necessary to design a system lightweight enough to require only a few launches. A handful of countries and companies aim to deliver space-based power as early as a decade from now.
Blogger's Note, as of right now, that list of companies include: 
SpaceEnergy (http://www.solarenspace.com/)
Solaren (http://www.solarenspace.com/)
ManagedEnergy (http://managedenergytech.com/)
Welsom Solar
PowerSat (http://www.powersat.com/)
HelioSat
PlanetPower
Packer Engineering (http://www.packereng.com/services/research_development.html)
Space Island Group http://www.spaceislandgroup.com/solarsat.html)
and several of the major Aerospace and Energy companies have displayed tepid interest.

09 July 2009

SpaceEnergy to Engage China on SSP

According to its newsletter: On the 18th and 19th of this month, Space Energy will also conduct a workshop on SBSP in Shanghai. In attendance will be several representatives from the Chinese Government’s energy sector, along with commercial and technical experts in the photovoltaic field.

22 April 2009

Will Space-Based Solar Power Finally See the Light of Day?

This is one of the best, most comprehensive articles written on the subject. Kudos to Adam Hadhazy and SCIAM!
Scientific American: Features - April 16, 2009
Will Space-Based Solar Power Finally See the Light of Day?
A satellite that reaps the sun's energy in space and beams it down to Earth for use as electricity may leave the realm of sci-fi and edge closer to reality this week following an energy deal in California
By Adam Hadhazy
Pacific Gas & Electric Co. (PG&E) has long invested in renewable energy sources, including geothermal, wind and solar. Earlier this week, the utility company reached for the stars in announcing the first-ever deal of its kind: The California power utility, says spokesperson Jonathan Marshall, plans to purchase clean energy generated by a satellite beaming solar power from orbit.The agreement between PG&E and Solaren Corp., an eight-year-old company based in Manhattan Beach, Calif., still hinges on state regulatory approval. If the deal gets the green light, Solaren must then privately raise billions of dollars to design, launch and operate a satellite as well as an energy-receiving ground station slated for the Fresno County area, says Cal Boerman, director of energy services for Solaren.The challenges of building this satellite (due to be completed in 2016) and introducing so-called space-based solar power (SBSP) remain formidable. But driven by the urgency of climate change and the lowering costs of solar technology, a growing number of countries and companies believe an energy revolution could be in the offing.Why bother harvesting solar energy directly from space? It is abundant, and "you can get [this] power 24/7," says Marty Hoffert, an emeritus professor of physics at New York University. Sunlight is some five to 10 times stronger in space, and its shine would reach energy-gathering satellites placed into geostationary (fixed) orbits—the realm of many currently deployed communications spacecraft—more than 99 percent of the time.SBSP could, according to energy experts, provide constant, pollution-free power—unlike intermittent wind and cloud cover–sensitive ground-based solar, and without the emissions of fossil fuels or radioactive waste from nuclear power. "[SBSP] is a disruptive technology [in that] it could change the whole energy equation," says Frederick Best, director of the Center for Space Power (CSP) at Texas A&M University in College Station, Tex.The premise (and promise) of SBSP has been considered scientifically feasible since the late 1960s. The basic concept of beaming microwave frequencies to Earth from orbit has already been proved: A fleet of solar-powered communication satellites routinely beam various electromagnetic frequencies to ground receivers, linking cell phone calls or relaying TV signals to rooftop dishes, for example. Converting solar energy beamed from space into electricity in a power grid, however, has not yet been demonstrated.Space Energy, a Switzerland-based SBSP start-up, aims to change that by deploying a prototype orbiter in the next several years, possibly before Solaren's pilot plant reaches orbit. "You can argue the physics [of SBSP] all day, but you'll only know with a prototype," says Peter Sage, a co-founder of Space Energy, started in 2008.Last year, U.S. and Japanese researchers crossed an important SBSP threshold when they wirelessly transmitted microwave energy between two Hawaiian islands about 90 miles (145 kilometers) apart, representing the distance through Earth's atmosphere that a transmission from orbit would have to penetrate, says Frank Little, associate director of the CSP.Many other technologies relevant to SBSP have made "enormous progress" in recent years, says John Mankins, who led the Hawaiian island test as chief operating officer and co-founder of Ashburn, Va.–based Managed Energy Technologies, LLC. A little over a decade ago, the best photovoltaic efficiency, or sunlight conversion into electricity, was 10 percent, Mankins says; now it can reach 40 percent. And satellite technology has also improved: Autonomous computer systems as well as advanced, lightweight building materials have also made leaps and bounds, he says.Despite such progress, and spending some $80 million, SBSP has not gotten past the U.S. government's drawing board so far. A key reason, Little says: NASA does not do energy, and the U.S. Department of Energy (DoE) does not do space.The U.S. Department of Defense, however, has recently shown interest in SBSP. Air Force Colonel M. V. "Coyote" Smith cites high fuel costs, along with risks to personnel when supplying petroleum to U.S. combat theaters and bases. A 2007 Defense report (pdf) from the Pentagon's National Security Space Office (NSSO), viewed the commercial development of SBSP quite favorably, especially as traditional, fossil fuel energy sources get ever scarcer in the years ahead. "We've got to identify sources of safe, clean energy in order to help us prevent energy wars in the future," says Smith, one of the authors of the 2007 report.The NSSO report said it would be in the fed's interest to encourage the commercial development of SBSP, but that the government should not design or operate the eventual orbiting power plants.The previous government work, including a joint NASA and DoE report from the 1970s about SBSP, has left its mark on many current architectural schemes, though. This textbook approach calls for a massive, microwave-beaming satellite several miles wide that would sport multiple enormous solar arrays connected to a central hub [like the artist's conception on the first page of the article]. The craft would be perched in orbit about 22,400 miles (36,050 kilometers) above Earth, or a tenth the distance to the moon. There, the satellite would maintain a geostationary, or fixed, position relative to a point on Earth's surface while its solar panel arrays bask in the constant sunlight.Captured solar energy then gets converted on board the satellite into electromagnetic carrier waves, specifically microwaves, ideally at a frequency of either 2.45 or 5.8 gigahertz (both fall on the spectrum between infrared and FM/AM radio signals) for subsequent beaming back to the ground. At that frequency, the waves pass easily through the atmosphere, although some energy—physicists do not know exactly how much yet—would be lost during the transfer, Smith says.This invisible column of microwave energy, measuring perhaps a mile or two (two to three kilometers) across, would be beamed at an oval-shaped, ground-based rectifying antenna, or a "rectenna," of similar size, and from there the energy would flow into the traditional electrical grid.Despite the clear analogy to a science fiction death ray, scientists believe the diffuse energy beam from above would not pose a health threat to people or wildlife, even at its most intense center."Microwave radiation is nonionizing, just like visible light or radio signals," says Jim Logan, former chief of medical operations at NASA's Johnson Space Center and an expert on aerospace medicine. That means it lacks sufficient energy, like x-rays and gamma rays, to remove an electron from an atom or a molecule to make a charged particle that can damage DNA and biomolecules, he says.Birds passing through the heart of the carrier wave from space might feel some warmth, Logan wrote in a February white paper on SBSP safety for Space Energy, but not at elevated levels. And should the beam stray from its rectenna target, it would be designed to defocus, Logan says, and not "run amok all over the landscape." Sage of Space Energy says: "We won't be frying birds or turning clouds to steam."Space Energy's first operational array, which adheres to the typical SBSP setup just described, would be designed to generate one gigawatt almost continuously, about the same output as a large nuclear plant. Pursuant to a successful prototype experiment in several years, Space Energy expects that investors would pony up the billions estimated to make a full-scale commercial plant a reality.Building segments of the plant's solar arrays on Earth, along with supports and a central transmitter, would take two years or so, says Stephan Tennsel, CEO and co-founder of Space Energy. Some 40 to 60 launches would boost all the components for the first SBSP satellite into a low Earth orbit (LEO) where a combination of automatic panel unfurling ("like an umbrella," Tennsel says) and robots would assemble and integrate them.Dangers and engineering challenges abound, however: Space junk like that which recently threatened the International Space Station, for example, could collide with the skeletal space solar satellite during assembly. And keeping the satellite's huge beam and the distant rectenna reliably synced up also stands as an unsolved technical issue, says CSP's Little.Overall, the how may be much easier to overcome than the how much. "Technically, we're a lot closer to space-based solar power than we are economically," Little says. The biggest obstacle, he says, continues to be launch costs. "Large structures in space are not showstoppers, but the cost of getting up into space is the real hang-up [for SBSP]," CSP's Best says. In Space Energy's business plan, for instance, half of the $250 million allotted for their communication satellite–size prototype goes toward just lofting the approximately 1,760-pound (800-kilogram) craft into orbit.Though Solaren is tight-lipped about what its pilot power plant will look like, a 2005 patent retained by the company indicates that the firm intends to use mirrors—another oft-explored SBSP element—to gather and focus sunlight prior to converting it to microwaves. According to the patent, Solaren also looks to eliminate many of the structural connectors on its craft—that is, some or all of the satellite's components, including the mirrors, power module and microwave emitter could be "free-floating" in space, orbiting in tandem. "The big thing is to get the weight down so the weight costs don't kill you," says Solaren's Boerman.Backers of SBSP hope that the rising commercialization of space—sparked by the allure of space tourism and the economics of cheaper access—will bring down the expense of rocketing into orbit. Some of the best-known entrepreneurial ventures include Richard Branson's Virgin Galactic and Elon Musk's SpaceX, but almost 20 companies are trying their hand at lowering launch overhead. "These organizations could potentially change the picture of launch costs," Best says.Many other obstacles stand in the way of commercially viable SBSP. A crucial regulatory matter: getting clearance from the U.N.'s International Telecommunication Union (ITU) that allocates use of the electromagnetic spectrum. SBSP's ideal microwave frequencies are already used by wireless systems such as Bluetooth, according to Smith. "Even if we could narrow the beam [from space] down and ensure complete signal integrity in the broadcast wave area," the ITU may deem the possible interference from SBSP as too disruptive to some extant technologies, he says.Some think that SBSP efforts should zero in on lasers rather than microwave transmission to avoid this and other confounding issues. "I think an approach using microwaves is doomed," N.Y.U.'s Hoffert says. Given the necessary size of microwave transmitters and their solar arrays, "it's a huge capital investment before you get one kilowatt of power," he adds.A higher efficiency, laser-based approach would require far smaller satellites and transmitters, perhaps requiring just one launch, Hoffert notes. One proposal involves capturing sunlight in space via photovoltaics, converting the energy into a visible or an infrared laser and then beaming this concentrated light onto existing solar panel arrays in the desert around the clock. Weather can disrupt laser transmissions, however, and Hoffert says other technical hurdles remain for both microwave and laser light approaches.The Japan Aerospace Exploration Agency (JAXA) is covering all bases as Scientific American magazine reported last year. JAXA hopes to have a one-gigawatt satellite in geostationary orbit around 2030 that may use either microwaves or lasers to send its energy back home.Yet another school of thought involves placing solar-power generators and microwave transmitters on the surface of the moon, or even using a lunar base to construct the satellites before launching them (with relative ease, due to moon's far weaker gravity) into a geostationary orbit. Many of the raw materials for crafting the satellites could be mined from the moon as well.If these and other far-flung, future missions ever come to pass, their creators may look back on PG&E's faith this week in Solaren as a key moment in the history of SBSP development, Logan predicts. "If [Solaren] is able to deliver this energy, you're talking about the first time space-based resources have ever been imported to Earth," he says. "It's a significant breakthrough in the awareness of the fact that we're not limited to just the resources on the planet."Auspiciousness aside, Solaren has a long road ahead of it in terms of raising capital and constructing the first-of-its-kind SBSP operation. Soothing local fears of death rays from space will also take some finessing, Logan admits.In the end, PG&E has not invested its customers' or shareholders' finances in the deal, says Marshall, the company spokesperson; rather, Solaren is on the hook to deliver the power first. Over 15 years, Solaren has agreed to provide 200 megawatts of electricity almost continuously, enough for a quarter million homes, starting in June 2016. "Even though PG&E took pains to assure the public they were not investing and that it was only a supply contract, it is still a big step," says CSP's Little. "If another energy supply contract is signed in the near future, I expect interest in space solar will really accelerate."