Space-Based Solar Power Beams Become Next Energy Frontier

popularmechanics.com ^ | January 2008 issue. | Erik Sofge

[shove_it]

They're officially all the rage in the Pentagon and the private space industry: orbiting satellites that send solar power back down to earth to fight global warming—and turn a profit.

Space-based solar power may become an important energy source as fossil-fuel supplies dwindle in midcentury: A single 1-kilometer-wide solar array could collect enough power in a year to rival the entire world’s oil reserves.

snip

A Pentagon report released in October could mean the stars are finally aligning for space-based solar power, or SBSP. According to the report, SBSP is becoming more feasible, and eventually could help head off crises such as climate change and wars over diminishing energy supplies. “The challenge is one of perception,” says John Mankins, president of the Space Power Association and the leader of NASA’s mid-1990s SBSP study. “There are people in senior leadership positions who believe everything in space has to cost trillions.”

The new report imagines a market-based approach. Eventually, SBSP may become enormously profitable—and the Pentagon hopes it will lure the growing private space industry. The government would fund launches to place initial arrays in orbit by 2016, with private firms taking over operations from there. This plan could limit government costs to about $10 billion.

As envisioned, massive orbiting solar arrays, situated to remain in sunlight nearly continuously, will beam multiple megawatts of energy to Earth via microwave beams. The energy will be transmitted to mesh receivers placed over open farmland and in strategic remote locations, then fed into the nation’s electrical grid. The goal: To provide 10 percent of the United States’ base-load power supply by 2050.

Ultimately, the report estimates, a single kilometer-wide array could collect enough power in one year to rival the energy locked in the world’s oil reserves.

snip

[thackney]

7,641,193 Trillion Btu / 3412 Btu per kWH = 2,239 Trillion kWH
= 2,239 Million MegaWH
= 2,239 Thousand GigaWH
= 2,239 TerraWH

I think they are still way off.

But not a single satellite but a continuous band of solar arrays circling the earth? Maybe 275,000 km in total length? That would get closer, with shadows and angle of incidence you would have probably a 1/3 the available power of a continuous flat array. I think they are still way off.

[thackney]

Oops, Terra Watt years, not Terra Watt hours.

Okay, it is in the ball park.

Thanks for the information about what they intended to build, I didn’t catch that.

So theoritically possible. I wonder how many times greater than the World’s GDP would be the cost of building such a structure. Pretty tough to calculate since the scale of the project would make meaningless most of the cost values we could find.

[theFIRMbss]

>Putting entire Chinese factories in orbit and wafting down palletloads of high value manufactured goods

Right. And when Chinese
get pissed over a recall,
a load will 'waft down'

onto say, New York...
Orbital anything will
someday kill millions.

[hippyhater]

The NASA doc seems to back up their theory. At the very least, we have a neat new weapon to keep the CHicoms in check.

[SunkenCiv]

Thanks kevindavis.

orbiting satellites that send solar power back down to earth to fight global warming... massive orbiting solar arrays, situated to remain in sunlight nearly continuously, will beam multiple megawatts of energy to Earth via microwave beams. The energy will be transmitted to mesh receivers placed over open farmland and in strategic remote locations, then fed into the nation's electrical grid.

I think these receivers should be located on some beautiful beachfront property I can sell them in Florida. Or for those who don't know, on the Brooklyn Bridge (I'm also selling that).

The late Gerard K. O'Neill used to tout this as one of the waves of the future that he foresaw, one of the great benefits to moving human civ out into space. I'm surprised I've never read how the technology for the so-called space elevator concept could be used to build an extension cord to conduct the generated electricity to the surface from geostationary satellites.

I declare a patent on that idea, BTW. ;')

[Kevmo]

For the renewable energy ping list.

I remember seeing some proposals like this in the 1970’s.

[mikrofon]

massive orbiting solar arrays ... will beam multiple megawatts of energy to Earth via microwave beams. The energy will be transmitted to mesh receivers placed over open farmland and in strategic remote locations, then fed into the nation’s electrical grid

Around these locations there will be an explosion in KFC and other fast-food franchises...

[BreezyDog]

and we all know how realistic of a guidepost simcity can be...

The results of raising and lowering taxes is spot on...at least back when I played it in the early mid ninties.

[Cvengr]

Either that or some nice satellite based weapons systems. (and you thought that nifty GPS in your car helped you track your milage.)

[RightWhale]

Even the founder has abandoned the company. The real players will be the major corporations.

[timer]

good number crunching. Once again it’s an area vs volume ratio. Solar has to cover huge AREAS, oil/coal is already bunched up into small VOLUMES.

[anymouse]

For those interested in learning more about Solar Power Satellites, please visit this forum - Solar Power Satellite Place at http://tech.groups.yahoo.com/group/solarpowersatelliteplace

[John Jamieson]

Thanks so much for the calculations! I love when someone actually puts pencil to paper.

[colorado tanker]

This kind of thing is usually done by a megalomaniac intent on world domination, like Scaramanga in the Man with the Golden Gun, Gustav Graves in Die Another Day or Blofeld in Diamonds Are Forever.

[Kozak]

Yeah, and the first time a birdie migrates through the beam, or they discover a purple titmouse burrow near the collector the greenies will nix this form of energy too.

[NYCRebublican]

Is that 1,365 watts per sq. meter per day?

[DungeonMaster]

Space-based solar power may become an important energy source as fossil-fuel supplies dwindle in midcentury: A single 1-kilometer-wide solar array could collect enough power in a year to rival the entire world’s oil reserves.

BS

[thackney]

Is that 1,365 watts per sq. meter per day?

Watts is a measurement of power, not energy. It is an instantaneous unit. You need to measure "watt x time" to have a energy measurement during a duration. Typically it is measured in kiloWattHours or larger units.

[NYCRebublican]

Thanks

[Kellis91789]

A band as shown which is in geosync orbiting around the equator would have 75% of its surface dark at any one time.

A flat donut in a polar orbit would have 100% of its surface in sunlight all the time. Of course, that way you’d need to be constantly aiming the microwave beam since the ground below you would be moving. And microwave transmission efficiency would fall off whenever the receiver grid wasn’t directly below.