NEW PLAYER IN SPACE SOLAR

PowerSat: Space Solar Flies Closer to Earth
Jennifer Kho, June 16, 2009 (Earth2Tech via Reuters)
and
PowerSat Files Patent That Accelerates Viability Of Space Solar Power (SSP) Satellite Systems; Two advanced technologies reduce the cost of developing a new base load generation system from space by roughly $1 billion
Aaron Lindenbaum, June 16, 2009 (PowerSat)

SUMMARY
PowerSat Corp. has filed a provisional patent for two technologies, BrightStar and Solar Power Orbital Transfer (SPOT), that could help make the transmission of space solar power (SSP) more cost-effective by reducing the price for launch and operation of a 2,500 megawatt SSP station by ~ $1 billion.

Solaren, another SSP company, recently signed the first-ever power purchase agreement for the delivery of 200 megawatts of solar energy from space with California megautility PG&E. (See ANOTHER LOOK AT SPACE BASED SOLAR)

Space Energy, a Swiss SSP company, is working toward the launch of a prototype satellite in the next 2-to-3 years.

The basic idea behind SSP is to use orbitting satellites, called powersats, to beam solar energy in space, many times more potent than the hottest brightest desert, to earth. Unlike the intermittent solar energy on the planet's surface, SSP is uninterrupted and virtually unlimited emissions-free energy undiminished by atmosphere or cloud cover. Operating 24 hours per day, 7 days per week, a powersat system would receive 25 times the energy of a comparably-sized solar power plant at (theoretically) the cost of a large hydroelectric power project.

(click to enlarge)

An SSP system is composed of proven technologies: Standard satellites, standard high capacity solar panels, electricity to radio wave converters and radio wave transmitters and receivers. The companies working in SSP agree a utility-scale system should be deployable within the next decade.

Having obtained $3-to-$5 million in angel funding, PowerSat Corp., a partner of PowerSat Limited in London and a subsidiary of PowerSat International in Gibraltar, filed U.S. Provisional Patent No. 61/177,565 for “SPACE-BASED POWER SYSTEMS AND METHODS.” The company, founded in 2001, will begin the proof of concept process with a 10-kilowatt demonstration of wireless power transmission capability on Earth. It, meanwhile, is negotiating a first venture round of further financing in “the single-digit millions.” It hopes to launch a $100 million, low-earth-orbit project by 2015 and partner with a utility or government agency on a utility-scale project of ~2.5 gigawatts, at a cost of $4-to-$5 billion, between 2019 and 2021.

http://www.youtube.com/watch?v=4TYhYrnKd5Y

From wmaness via YouTube

COMMENTARY
SSP is a science fiction-sounding concept, implausibly Tomorrowland to some and excitingly imaginative to others. Everything in the concept, though, is a proven technology.

The same satellites that now carry the communications systems transmitting cell phone and television signals will carry solar arrays in the same kinds of geosynchronous orbits. The solar arrays are essentially the same as those now used to power the international space station and, in general, the same kinds of thin film solar panels as the ones on rooftops around the city.

The solar arrays generate direct-current (DC) electricity which is converted by the satellite communications equipment into radiowaves, the same radiowaves that send enertainment to a car radio or voices between cellular phones. The communications satellites send a beam about a quarter the density of sunlight to ground receiving stations on earth that convert the waves back to DC electricity which is then sent into the transmission system, potentially by the gigawatt, to power air conditioners and laptop computers and electric toasters anywhere and everywhere that transmission wires go.

Satellite solar array sending radio wave enery. (Image from Kris Holland/Mafic Studios - click to enlarge)

SSP has been a theory since at least the 1960s. As science has caught up with imagination, the plausibility has advanced theory into hypothesis. It is still, according to PowerSat, thought to be a risky place to invest billions of dollars because the power that is generated may not be enough to return a profit on the expense. That won’t really be clear until a powersat system is in place but to put one in place somebody is going have risk the price of a launch.

The first of PowerSat’s 2 breakthrough cost cutting technologies is called BrightStar. It reduces the single big, array-carrying satellite into a cluster of hundreds of small satellites that work together in a form of wireless electronic connectivity to broadcast a single beam to the earth receivign station, called a rectenna. BrightStar allows for the launch of a constellation of beaming elements in varying capacities. They are joined in a more efficient system that is more reliable because a failure of an element does not mean the failure of the entire system and faulty individual elements can be replaced without causing down time for, or replacement of, the whole system.

The other breakthrough PowerSat technology, Solar Power Orbital Transfer (SPOT), allows the solar array’s electricity to be used to power the satellite’s electronic thrusters. The thrusters boost the satellites from Low Earth Orbit (LEO, 300-to-1,000 miles up) to Geosynchronous Earth Orbit (GEO, 22,236 miles up). Using solar energy-generated electricity for the boost eliminates the need for a launch rocket to carry fuel into space to lift the system from LEO to GEO, cutting the weight of the launch by 67%, dramatically decreasing its cost.

In conjunction with new launch vehicles like the Falcon 9 from SpaceX that make the cost of lifting off more affordable, the PowerSat technologies seem to be turning science fiction into something more substantial than the stuff that Trekkers dreams are made of.

A receiving (rectenna) station. (Image from Kris Holland/Mafic Studios - click to enlarge)

QUOTES
William Maness, CEO, PowerSat Corp: “This patent filing is a watershed moment not only for PowerSat but for a renewables industry that, until now, could neither compete economically nor generate power at the base load scale of oil or coal…Today, the convergence of technology and energy demand, combined with the political will to wean us off of fossil fuels, enables space solar power (SSP) to fill a widening clean energy supply gap.”