I disagree with more than Simberg in Snead's presentation of a case for an aerospace plane and space based solar power (SBSP):

At $100 per barrel, America’s annual cost of imported oil is about $440 billion per year. During the six to eight years required to bring the aerospaceplanes into operation, America will send to foreign countries $2.6–3.5 trillion for imported oil. Every year that we fail to act to substantially decrease our need for imported energy is $440 billion spent unnecessarily in the future.

The $440 billion that we spend on imported oil is primarily going to fuel cars. SBSP would provide electricity. We can already save 90% on energy expense by switching from oil to electricity. If SBSP replaces the energy we are importing, there is still the expense of batteries and electric propulsion or similar. The cost of the batteries and hybrid or electric propulsion system is more expensive than the fuel saved for many drivers.

In sum, we can already achieve energy independence from foreign oil simply by building more coal-fired power plants and implementing electric cars. But we are not implementing electric cars with cheap power from coal. Why would we do so with expensive power from SBSP? And expensive it would be.

The near-term system Snead refers to costs $70 billion to develop and will cut costs to orbit to $1000/lb (including development costs) if there are 240 missions per year to deliver six million pounds to LEO. More expensive to GEO. With manufacturing costs $160/lb and solar only 4x as efficient as terrestrial solar, Snead's space plane has done nothing to reduce the cost of solar from terrestrial costs much less make it competitive with coal for electricity or electricity competitive with oil for transportation.

---- Update 12/5/7 4:00 PM CST ---

Charles Miller pointed out that there are plenty of high value off-grid uses of power where terrestrial solar is unsuitable. Anywhere that generator fuel is being flown in comes to mind: that's about $6/kwh; 625,000 lbs of solar cells can deliver 20 MW of continuous power at that price ($1B/year) for perhaps $20 billion (which would be $32,000/lb all in). For 1 GW at $0.30/kwh (a good guess at the value of the median off grid use for which terrestrial solar is unsuitable), it's $2.5B/year revenue which at $1,000/lb in launch costs + $150/lb in manufacturing costs at about 45w/lb would cost about $25B. That's definitely achievable by current space technologies at a flight rate sufficient for 1 GW/yr in installed capacity (22 million pounds) much less 20 GW/year for 10 years for 10% of US 2040 power needs (440 million pounds/year or trillions of dollars of launch demand over the ten year window). $440 billion in launch demand per year would be about 150 times the current annual money demand and would require a steep ramp up.

I am forced to retract my criticism of Snead since this closes the revenue portion of the business case for his space plane: demand for $1000/lb launch costs would allow 150 million pounds of SBSP to deliver 6.75 GW of electricity after 25 years at between $0.50 and $1 per kwh which is worth $30-60 billion per year. The plane/SBSP program could be paid for out of revenues in less than 10 years after it starts flying and after three years if the SBSP generators can be sold for ten times annual revenue.

I'd think it would be easier to use the electricity to do the coal -> syngas conversion than to both build the coal plants _and_ convert all the vehicles.

Can't do that. Coal is EVIL and causes GLOBAL WARMING!!!!one

Sam,

What makes you think all that imported oil is fueling cars? I think it's mostly fuel oil and plastic. Check your facts and figures. Something like thirty to forty percent of our gasoline is imported from refineries in the Carribean. I don't think that gasoline is even counted in our "oil imports" since, strictly speaking, it's not oil anymore.

"What makes you think all that imported oil is fueling cars?
Posted by Jardinero1 at December 3, 2007 04:49 PM"

Because in fact, it is.

Sam, my agreement with Snead was about the need for the infrastructure he describes, if we want to become space faring. It had nothing to do with whether or not SBSP is an economically viable idea. I'm an agnostic (on the skeptical side) on that.

I may be wrong, but aren't most plastics made from natural gas, not crude?

I think you are right Big D.

IIRC, only about 10% of Crude is used as feedstock for plastics and asphalt.

Food for thought:

http://www.export911.com/ref/oriPlast.htm

Gasoline makes up less than half of refinery production in the US. Other products i.e. inputs for plastics makes up about a quarter. Fuel oil is the rest. I refer you to this table for the numbers:

http://www.eia.doe.gov/emeu/finance/usi&to/downstream/update/#tab3

I stand corrected on the amount of imported gasoline. The actual amount is on the order of nine to twelve percent, but growing.

I don't know if we stopped importing oil, as Sam proposed, how that would affect plastic production. I am not sure we wouldn't need the same amount of crude oil inputs to produce the same amount of distillates for plastic. Does anyone know that to be the case?

The problem with Mike's approach is that it requires all these expenditures before you make the first dollar off of any space enterprise. This requires that the government foot the bill, which requires politics, and the politics just aren't there to support this idea.

He knows this and yet continues on. God bless him and I hope that he enjoys spending the time on this but I am tired of wasting time on grand plans like this.

The highest volume plastic is polyethylene, IIRC. The monomer, ethylene, is made by thermal cracking of light hydrocarbons ("naphtha"), hydrocarbons that are too light to use in gasoline.

Most of the oil used in the US is used for transportation -- gasoline, diesel fuel, jet fuel. This share was 68% in 2006. Relatively smaller amounts are used for home heating, electricity generation, and as a chemical feedstock.

BTW, at $3/gallon and with its combustion heat captured at 80% efficiency, you would break even replacing oil heat with electric resistive heat if electricity were less than about $.09/kWh. I suspect there is already a lot of this substitution going on, since the capital cost for electric resistive heaters is small ($50 for a room sized unit), and that figure does not include the savings from being able to fully heat just the areas of the home being used.

Whatever the oil is being used for, it can be replaced with electricity generated from anything that costs less than 10 cents per kwh, instead of SBSP. That may include wind, coal, nuclear, and even terrestrial solar. For heating applications, one doesn't necessarily even need photovoltaics.

The point is that SBSP solves a problem we don't have: cheap, plentiful, independent sources of electricity. If we want independence from foreign oil, we have to find cheaper substitutes for the jet fuel, gasoline and plastics that we are using it for. Cheaper than the current price of electricity and a cheap conversion process. If we renounce the cheapest fuel supply (at the margin given our existing infrastructure), we will drive our own cost of energy up and the cost of energy for the rest of the world down. Less money for oil-rich countries like Canada, but less expense for importers like China.

Rand: Producing a $75 billion space plane is pushing on a noodle. The plane would not pay back bond holders: $6 billion/year Snead needs for six million pounds is twice the worldwide annual military and commercial demand and the 25000 lb payload limit crowds out some of that demand. The plane would default on its bond debt. Maybe after that at $500/lb it would have enough demand to have high utilization, maybe even for SBSP. Better to subsidize payloads and let people like you innovate to get them there.

Paul,

Thanks for the analysis on the cost of heating oil. I never understood burning oil for heat. Off peak electricity here (when you would do most of your heating) is 3.5 cents/KWh, and natural gas is cheaper than electricity. Is electricity that much more expensive in the Northeast?

Mark in AZ

Producing a $75 billion space plane is pushing on a noodle.

I don't agree that we should build a $75B space plane. I'm not even sure where that number came from.

Mark - the short answer is yes, it is that much more expensive.

My numbers are not completely up to date, but I haven't heard anything fundamentally shifting the relationship. (Like a raft of nuclear plants.)

In the West, there's a lot of hydroelectric power. A substantial fraction of the entire western grid. In Washington, we were getting electricity at $0.04 per kW-hr. I moved to upstate NY -> $0.20 per kW-hr.

There isn't a really good transmission system from the 'western grid' to the 'eastern grid', and the losses incurred are too high for those two numbers to approach one another.

In the West, there's a lot of hydroelectric power.

There is also lots of very cheap sub-bituminous coal (Powder River Basin, for example).

The $70 billion came from Snead's paper which I linked to; that gets two separate launch systems for added reliability that at least one kind will be working. If the $1000/lb works for SBSP in volume the only question is whether the $35 billion development is fundable.

Charles Miller pointed out that there are plenty of high value off-grid uses of power where terrestrial solar is unsuitable.

And microwave SSP is also not suitable, since the users are too small. So you'd need laser SSP, so you can scale the system down. Fortunately, high efficiency fiber lasers appear to be making some progress.

Don't space lasers suffer from some of the same problems as solar? Or is there a frequency we can lase that doesn't mind cloud cover?

Clouds would be a problem -- but night wouldn't be a problem.