National Space Society Position on Space Solar Power in Economist Magazine Debate

The Economist magazine has conducted an open, on-line forum on the topic, “Can Solar Energy Save the World,” which concluded on Friday, November 8, 2013. The Washington DC-based National Space Society (NSS) has voted “YES” in this debate.

NSS urges that the European Union (EU) allow Space Solar Power to be given equal treatment with other sources of renewable energy as part of the European system of feed-in tariffs, which have worked for ground-based solar power to create a viable new market for energy. Feed-in tariffs are a guaranteed offer of a price and a market to generators of renewable electricity and not a tax on imported goods.

Dr. Paul Werbos, Chair of the NSS Policy Committee, said “What are some good strategies to really help develop space resources? The best strategy is one which tries to ‘kill two or three birds with one stone.’ And so, at nss.org/EU [and reproduced below], you will see a new position statement aimed at three goals — to create new jobs where they are badly needed in the EU, to accelerate low-cost forms of solar farms on Earth, and to set the wheels in motion for serious market-oriented investment in space solar power.”

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National Space Society Statement on Space Solar Power (SSP) and Feed-In Tariffs

Germany has long had a feed-in tariff system (EEG), which, among other things, guarantees a market and a price for large scale wind and solar farms. Some critics argue that these should simply be abolished, because of the damage they claim has been done to the German economy; however, the German economy seems to be doing quite well, compared to other major developed economies on Earth. The feed-in tariff is not a tax or a tariff like the tariffs we pay for imported goods; it is essentially just a guaranteed offer of a price and a market to generators of renewable electricity.

Just as we urge opening up the launch services market to more competition and new technologies, the National Space Society (NSS) also urges opening up the European electricity market to more large sources of renewable electricity. For the sake of lower energy prices, greater competition and greater economic stability, we propose that the feed-in tariff for large solar farms be extended to all solar farms in the European Union, and also to all rectennas to be located in the European Union supplying electricity from energy beamed from space.

Even just a year ago, the possibility seemed to be remote that industry might build such rectennas; however, the new design and analysis at www.nasa.gov/pdf/716070main_Mankins_2011_PhI_SPS_Alpha.pdf, combined with potentially useful efforts on key technologies to reduce the cost of access to space such as the DARPA XS-1 program and private sector efforts like SpaceX and others, suggest that we should not rule out such a development.

In the market based approach, we do not choose which technology we believe in more; rather, we offer the same incentive to all forms of benign solar energy anywhere in the EU, and let suppliers decide for themselves what to invest in and where. A firm price guarantee can be very useful in stimulating the kind of private sector investment and jobs which all major economies need today. For the EU, especially, a new supply of renewable electricity would be a great thing for consumers, who otherwise would be paying for more expensive offshore wind or imported natural gas — so long as solar suppliers on Earth or in space can meet the offer price. As in the past, this should be a standing law, allowing suppliers to decide on their own schedule for deployment.

Near-Extinction Event in 1883 Indicates Threat from Space May Be Greater Than We Thought

NSS Board of Directors member Al Globus reports:

We have known for some time that Near Earth Objects (NEOs) are a serious threat to civilization. We also know, more-or-less, how to reduce that threat significantly at very reasonable cost. We have thought, however, that comets were much less of a threat which is a good thing, as they are much harder to deal with.

Unfortunately, it appears that a large comet may have missed Earth by only a few hundred kilometers in 1883. If the comet fragments “had collided with Earth we would have had 3275 Tunguska events in two days, probably an extinction event” [MIT Review].

We know that comet Comet Shoemaker–Levy 9 struck Jupiter in 1994. Comet C/2013 A1 is currently believed to have a 1-in-8,000 chance of striking Mars in October 2014, passing within 120,000 km. That’s close enough to endanger satellites orbiting the Red Planet.

It appears that either we are in a period of unusually frequent close encounters with comets, or cometary threats to our existence are fairly common. Defense against comets is much more difficult than against NEOs. Comets spend most of their lifetime in the far outer portions of the solar system where they are hard to observe, and when they do come through the inner solar system they are usually moving very fast, giving little time to respond even if we detect the threat before a collision.

NASA spends about $20 million/year of NEO detection, most of which pays for ground telescopes. For one percent of NASA’s budget ($160 million per year) we could have an absolutely outstanding NEO detection and deflection program. The immediate need is for an infra-red space telescope to find most of them, for example, the B612 Sentinel. As NEO defense is essential to our survival, it is a little silly, and potentially criminally negligent, that we spend orders of magnitude more money on very interesting, but much less important, projects.

Cometary defense, however, is not cheap. Detecting a cometary threat in time to do something about it requires extremely capable telescopes. Comets are dirty snowballs which tend to break into pieces making them very difficult to deflect. If further analysis finds comets to be a significantly greater threat than currently believed, be prepared to open the checkbook.

Clues to the SpaceX “Big Rocket”

NSS Board of Directors member John K. Strickland reports:

A major clue to the “Big Rocket” from SpaceX (bigger than the Falcon Heavy) was recently revealed when an agreement with the Stennis Space Center to test the Raptor engine showed that its vacuum thrust is almost 600,000 lbs. We had been expecting a much smaller engine for upper stage use. This means the methane oxygen engine could be used on both the first and second stages of the Big Rocket.

We could assume that the same configuration as the Falcon 9 is used, with the upper stage having a single engine with a nozzle extension to allow greater thrust in space, and with the engine-out capability of the 9 engine Falcon 9, duplicating its basic eight-and-one first stage configuration with the new engines. This would mean that the Big Rocket’s total thrust would be about 5.4 million lbs of thrust (about 2500 tons at sea level), more than 2/3 that of the Saturn V, and with more efficient engines to boot.

Methane engines have a higher specific impulse than the RP1 and oxygen used in the Merlins. The new engine will also use combined cycle or closed loop combustion, a significant improvement over the existing Merlin engine design. This means the engines can produce more thrust with the same amount of fuel, part of Musk’s deliberate process of “continuous improvement.”

One observer wondered if the rocket could use 11 such engines, 10 in a circle and one in the middle. This would depend on the width and spacing requirements of both the engines and the first stage circumference. With this configuration, the total thrust would be 6.6 million lbs.

This means that the Big Rocket is not just a publicity gambit, as some critics have alleged. The 27 foot diameter given for the Big Rocket now makes sense. Such a rocket could launch cargo or vehicles up to 40 feet in diameter in a reverse fairing.

An article in the Oct 28 edition of Space News says that parts for the Raptor methane-oxygen engine will be tested at Stennis early in 2014. This indicates that Raptor development is well under way. It is unclear how long it will take to build a new test stand for a 600,000 lb thrust engine, six times what current stands there can test.

The engine is described as “highly reusable.” One would then think that the HLV Big Rocket it is designed to work with would also be “highly reusable.” The SpaceX spokesperson said that it was the first in what would be a family of engines. Based on the known development times for the Falcon family, the Big Rocket should be ready to fly (and land for another flight) well before 2020.

It is unclear if such engines will be tested at any other locations, and also what the schedule might be for the actual rockets that would use them. A short, fat booster is structurally much easier to get down into the troposphere intact than a long skinny booster like the Falcon 9.

References:

http://www.nasaspaceflight.com/2013/10/spacex-press-abort-test-raptor-engine/

http://www.spacenews.com/article/launch-report/37859spacex-could-begin-testing-methane-fueled-engine-at-stennis-next-year