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On Why We Need CCS, Part 2: Reactive Climate Change Mitigation

The carbon problem is mostly an energy economics problem because coal is such a cheap way to make electricity, on the order of half the projected end point of solar (zero cost for the PV surface).

So if you want something to displace coal without opposition, it needs to be less expensive.  If you want it to take over in a hurry, then it needs to be much less expensive.

If you can figure out a way to get the cost to lift solar power satellite parts to GEO down to where it is perhaps a third of the total cost, then they clearly win in the energy market.

Cheap enough electric power will also solve the transport fuels problem.  Once cent per kWh power will make $30/bbl synthetic oil, two cent will make $50/bbl.  (Straight forward chemistry and existing plants in the billion dollar class).

So one way to solve the carbon and climate problem (to whatever extent carbon contributes) is to reduce the cost to $100/kg or less for lifting million of tons of power satellite parts to GEO.

 

 

May 9, 2014    View Comment    

On Dollar a Gallon Gasoline

Since the 70s, it's always been the case that the microwave intensitiy is less than sunlight.  Birds.

The reason is makes sense is that the amount of energy collected over a year is much higher, the rectenna converts at around 85% as opposed to what you can get from PV, and the thing works 24/7 insteat of about 1/5 of the time for PV.  The rectenna structure is a lot lighter too.  Being mostly open space, you don't have to brace it much against wind.

It's worth reading the Wikipedia article.

April 29, 2014    View Comment    

On Dollar a Gallon Gasoline

JP, have you considered electric power tractors?  Or big trucks?  Or locomotives?  Or jet aircraft?  How about ships?

Or for that matter, the cost of replacing the entire fleet of hydrocarbon powered vehicles.

Not saying we should not switch to electric vehicles, just that it has consequeces far beyond running down to the store for a loaf of bread.

 

April 9, 2014    View Comment    

On Dollar a Gallon Gasoline

Robert, try here https://en.wikipedia.org/wiki/Sun-synchronous_orbit

It's an orbit that uses the earth's equitorial bulge to precess as fast as the earth goes around the sun.

April 9, 2014    View Comment    

On Dollar a Gallon Gasoline

Royce, that's not much of an argument.  Earth's shadow eclipses GEO power satellites less than one percent of the time.  And it happens spring and fall when the power demands are so small that the grid can shift power an hour east or west to cover the outages.

Cost is the determing factor.  With the lift cost reduced to $100/kg, I make a case for power satellites cheap enough to displace coal, 2 cents per kWh, and I can go through all the steps to justify that cost.  What cost do you get for the Sun-synchronous orbit?

I can't make a case for existing launch vehicles even if the tranmission was free.

April 9, 2014    View Comment    

On Dollar a Gallon Gasoline

Roger, part of the problem is how seriously do we take the buildup of CO2 in the atmosphere? 

Is that more or less important than military surpemacy?

There is also the point that the need to defend mid east oil supplies will go down if synthetic oil is seen on the horizon.

Another factor is that a propulsion laser can only see about 1/3 of the earth at a time.  For example, if the Chinese and Indians built one, the optimal place for the propulsion laser is over about longitude 130.  From there, in GEO, you can't see any of the continental US, and even Hawaii is an extreme slant.

I like your ideas re multiple people being able to cut them off.  Perhaps using a signal that is required for them to opperate at all.  To avoid accidental shutdown, perhaps the loss of two out of 7 signals would turn it off.

April 6, 2014    View Comment    

On Dollar a Gallon Gasoline

Roger, if the US were to build power satellites including the propulsion lasers, what could the Russians do?

If the Chinese were to build propulsion lasers, what could the US do?  (Short of going to war.)  And if the EU did it, currently the most likely possibility, what could anyone do about it?

I am not saying you are wrong, just that I don't see (for example) the US having an effective arguement against the Chinese or a Chinese/Indian joint project to responsibly solve their energy problems.

 

April 6, 2014    View Comment    

On Dollar a Gallon Gasoline

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"What portion of humanity is concerned with gasoline?"

I am using gasoline as a catchall term for liquid transportation fuels.  Everyone who eats is concerned with fuel for the tractors that plow the fields to the ships that transport grain across oceans.  Do you fly?  If you do and you are concerned about the cost of tickets, you are concerned with the cost of jet fuel.

If you ever need a ride to a hospital, you are concerned about the cost of gasoline.  If you buy anything made out of plastic, you are concerned with the price of oil even if you don't know the details of the organic chemistry that makes plastics.

Gail Tverberg is deeply concerned with the pervasive effect of oil as goods and services move through the economy.  If you expect a pension, you are indirectly concerned with the cost of gasoline (oil).

Your concern for power satellites crashing into each other is misplaced.  They are worth more than communication satellites.  Keeping them in the right places would be a done at least as carefully with the added advantage that there would be plenty of people in GEO to deal with whatever problems came about.

I partly agree with you, "Right now there are no space craft that can do the job," but I disagree with "decades will pass before there are."  Reaction Engines will take orders for Skylons with delivery dates starting in 2021.  It will take 5-6 of them to haul the parts for the laser propulsion station to LEO.  That will take about a year, and then a couple of months to fly the station out to GEO where it can start hauling parts out for power satellites.

I find it amusing that people such as you object that Skylon has not flown.  As far as I know, there are no MSR around, and, as far as I know, no funds have been allocated to build one.  Let me know when there is progress and I will be cheering.  You might consider doing the same for Skylon.  It's not like these project compete for skilled workers or even funding.

I use gasoline simply because more people are aware of what they pay at the pump than they are for most other forms of energy.  Would you be more in favor if I emphasized desalinating water and pumping it inland for irrigation?  Cheap energy lets you recycle just about everything that now winds up in landfills.  Would it help if the proposal included sending the hundredth power satellite to Mars where it could support tens of tons per hour to and from the surface and to and from the earth?

April 6, 2014    View Comment    

On Dollar a Gallon Gasoline

NN, I don't mind criticism, but I would appreciate it if you get the numbers right.  For a search term, you might use "geosynchronous collision."  I don't think there have been any of them.  ". . . large number of devices in orbit," actually it's only perhaps 3000 of them.  They tend to be large, 5 GW each.  For the rest of your thoughts, you might want to talk to someone who is in the orbital mechanics business.  

My objection to nuclear energy cost is simply that it isn't cheap enough to make transport fuels at a low enough price to meet Gail Tverberg's criteria for a vibrant economy.  1-2 cents a kWh for TW of energy is a tough goal.  There are other problems, cooling water being a big one. 

As to dismissing this simply because it hasn't been done already, there is a reason.  It's only been a few years since lasers got big enough and cheap enough to consider using them to power rockets.

Your complaints about solar are well founded, though in some cases solar cost less than any other source of power.  The big problem with solar, of course, is the fact that the rated output happens at best only about 1/5th of the time.  Solar works a lot better in a place (geo) where the sun shines 99% of the time.  It works even better when you don't have to support the collectors against gravity and wind.

Re the rest of your concerns, if you are in the US, you don't need to worry about the cost of this project coming off your taxes.  Whatever merits and cost the project may have, it's very unlikely the US will have anything to do with it until we are buying synthetic transport hydrocarbons from the Chinese.

 

April 5, 2014    View Comment    

On Dollar a Gallon Gasoline

NN, the transmission of microwaves from space to the earth is not just theory.  It's the basis of the entire $100 billion communication satellite industry. 

Colisions in GEO don't genearte fragments since the relative speeds are, at most, in the fender bender range.  As you say, there are a lot of them up there and there has yet to be a colision.  Lower satellies in inclinded orbits are different.

Higher temperatures would be better, but the current versions of nuclear power plants disipate about 2kW of waste heat for every kW they put on the lines.  Rectennas disipate around 150 W for each kW they put on the lines.  I.e., nuclear reactors put about 13 times as much heat into the earth's ecosystem as power from space would.

I am not oppoised to nuclear reactors.  As you note, they have been around a long time.  They have problems, China, for example is finding it hard to place any more of them near sources of cooling water.

You might note that I am not a supporter of space based solar power unless it is substantially less expensive than anything except hydro.

April 4, 2014    View Comment    

On Dollar a Gallon Gasoline

Dennis, this is essentially Jerry O'Neill's space colony scheme.  It failed to take root because it cost too much and took too long.  The current estimate for this project is ~$60 B and ten years to 500% ROI.  The only recent work I know of for a lunar industral base up to the task of building power satellites was estimated at $2 T and generated no revenue for 20 yeears.

I know this stuff fairly well.  Normal 0 MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";}

http://en.wikipedia.org/wiki/L5_Society

Eventually, with nanotechnology, it will be possible to put an industrial seed in a coke can.  But that's a ways off.

 

April 4, 2014    View Comment    

On Dollar a Gallon Gasoline

Nathan, there have been communication sats in GEO for decades.  I have never heard of one of them being damaged by either natural space junk or human caused.  If this comes about, there will be thousands of people in GEO to recover anything that's not where it belongs.

I would be really interested if you have any idea about sabotage.  There would be upwards of 3000 power satellites separated by several hundred km.  They could, of course, be destroyed by a large number of nuclear weapons, but sabotage seems no more likely than trying to destroy a ground based solar power plant that way.

 

April 3, 2014    View Comment