Welcome to the Energy Blog

  • The Energy Blog is where all topics relating to The Energy Revolution are presented. Increasingly, expensive oil, coal and global warming are causing an energy revolution by requiring fossil fuels to be supplemented by alternative energy sources and by requiring changes in lifestyle. Please contact me with your comments and questions. Further Information about me can be found HERE.



After Gutenberg

Clean Break

The Oil Drum


Blog powered by Typepad

« Cypress: Solar Power to be Competitive in Five Years | Main | Scientific American Plugs Plug-ins »

March 18, 2006


Robert McLeod

Wow, that is so stupid it's not even funny. The concept they are describing is basically the Shuttle-C(argo) configuration which has been around since before the program started. NASA has looked at it, and ways to utilize the external tank, since the Freedom station days. Nothing has come of it. The weldalite can is not a vacuum vessel.

They don't seem to understand that you can't build an effective solar power system in low-earth orbit because it can't deliver power to a rectanna very often. The SPS (Shuttle) can't get to geosynchronous orbit, let alone lift the tank that high. The external tank is NOT carried to orbit.

There's a lot of issues with regards to basic microwave optics that don't appear to be on their radar. For example, to deal with the diffraction limit the antenna that transmits the power needs to be approximately a kilometer in size. The dish rectanna on the ground needs to be even bigger. We're talking the largest structures ever built by mankind here.

I find the suggestion that university research groups can afford to pay $25,000 a day for a tiny lab. That's $9 million a year. Very few universities could justify that sort of cash flow for such a limited payback.

File this under vapourware. Too optimistic to believe my cyanisiam? Take a look under the Jobs tab. They'll be hiring in 2004...


I've got to agree with Robert here, this is such a silly idea. It's not the first time its been proposed, nor will it likely be the last, but it is still pretty dumb.

Only 53% of the solar radiation incident at the top of the Earth's atmosphere is reflected back into space. The remaining 47% (or nearly half) makes it to the surface, and to your Earth-based solar facilities. That's not a very significant energy loss and hardly makes putting solar panels in space worth it.

The only way this could be worth it is you could build and operate your entire space-based solar facility for less than twice the cost of traditional land-based solar facilities. Considering the costs of launching everything into space, building space stations, land based recievers for this 'beemed' energy and of course all the solar panels, I doubt that this price target could be achieved.

Hey, I can't fault them for thinking big and dreaming of the stars, but let's focus on something a bit more realistic. Go ahead and try to prove me wrong though. I'm not gonna compain if by 2050, 90% of the planet's energy needs come from space based solar panels ... but you've got to admit, that sounds pretty rediculous.


You guys seem to know alot more about this topic that I do, but I don't think it's a silly Idea.

There was a time when space travel would have been laughable also.

Just because it's not feasible now or even in the next 20-30 years doesn't mean money shouldn't be spent on research. Onward and outwards as they say.


ps Nice detailed commentary and nice blog Jim.



I am not saying that this is an economical idea, but your numbers are a little off. A satellite with photovoltaic panels will receive sunlight 24 hours per day, as opposed to the average 5-7 or so at a given spot on the ground. So you are quadrupling the incident solar irradiance time as well as more than doubling the intensity, effectively multiplying it by 8. So if it costs less than 8x ground-mounted PV cost to launch PV as a satellite and microwave it down it could be economical.


The latest news on solar is that solar photovoltaic concrentrator designs are now aproaching 40% efficiency. That is 4 times the 10% efficiecy of flat panel arrays now in use.

That reduces the size of collectors needed to provide the same power to 1/4 of what they now are. And in a concentrating collector a fraction of the expensive part of the PV installation, the silicon wafers themselves, are needed.

And in a concentrating collector temperatures are high enough to use infrared PV cells as well to provide extra efficiency, maybe an added 15%? Also the higher temperatures can yield heat for cooking, heating domestic hot water, and home heating/cooling, for an extra 20%.

Overall efficiency close to 75% is possible. Compare the lower cost of this cogeneration design with the 8.5 year payback on this home solar installation.


A solar cogeneration system combining these well proven technologies to achieve this much higher efficiency of 75%, instead of the 10% efficiency of this real world 8.5 year payback would have a 5 year (or less)payback with no subsidies.

Add a small wind generator, around 12 feet in diameter, and a system of the same size as this New Jersey homeowner has installed (with solar cogeneration), will not only power his home (even charge an electric car), but it will provide electric power for a couple of his neighbor's homes as well.

So why this talk of economically impossible space based solar? A diversion maybe?

With global climate disaster severity growing at exponential rates, storms, droughts, ice caps melting, there is no time for diversion.

Out the scams and move on to practical schemes for renewable energy, SIG does not deserve publicity.


Whoops old blog address. Here it is updated.



Chris, you are right about that. My bad. That does give them a bit more room to work with I suppose. I'm still not sure they can pull it off, but they can certainly go for it.

Ralph Buttigieg


There are reasons to criticize this proposal but lets gets the facts straight. The outer shell of the tank may not be a vaccum vessel but the inner oxygen and hydrogen tanks are. The habitat would be build inside the propellent tanks. This is not new. Skylab was built in the propellant tanks of the Saturn 5. The original proposal was the "Wet" Skylab which would have launched the Saturn fully fueled and have the astronauts
fit out the tank. This would have allowed a Skylab module to be placed around the Moon. Lack of mission and lack of funds killed Wet Skylab not feasibility.

The Solar Satellite may be assembled in low orbit but theres no reason it has to stay there. The ample electricity produced can be used to power an ion engine to move the powersat to Clarke orbit. Ion engine have been used in Space for years by comsats for station keeping (which the SPS will also require)

The problem I have with it is that is way beyound anything yet attempted in Space . The ISS has yet to be completed, this will be several orders of magnitude bigger.



eric blair

Lets pretend the idea happens. Now you have heat being added to the Earth's envelope.

If one accepts global warming, how does adding heat to the envelope help?


There are also the obvious safety factors to consider. If I can make a MASER out of old microwave oven parts that can light a piece of plywood on fire at 100 yards with a microwave beam, what are we looking at if this power generating satellite goes slightly askew and starts cutting a kilometer wide swath of destruction across the country side because the super-double-redundant-nothing-can-go-wrong failsafes failed?

Alex Timiryasov

Make a better picture with parts and such!

I need for science class!


If you have looked into solar energy as a method for heating your home, panels are usually the first things that come up.

There are, however, other unique methods.

The Solar Heating Aspect You Have Never Heard of Before

The power of the sun is immense. The energy in one day of sunlight is more than the world needs. The problem, of course,

is how does one harness this power. Solar panels represent the obvious solution, but they have their downside. First,

they can be expensive depending upon your energy needs. Second, they do not exactly blend in with the rest of your home.

Passive solar heating represents a panel free method of harnessing the inherent energy found in the sun for heating

purposes. If you come out from a store and open the door of your car in the summer, you understand the concept of passive

solar heating. A wide variety of material absorbs sunlight and radiates the energy back into the air in the form of heat.

Passive solar heating for a home works the same way as the process which overheats your car in the parking lot.


you are all way to into this just accept it that aliens(japanese) are better than you.buahahahaha


this is a web site about the calculation of insolation for houses



this is a web site about the calculation of insolation for houses



Ralph Buttigieg above points to my big issue with space-based solar power: adding more energy (and all energy eventually becomes heat) to an over insulated planet. Even if it becomes economically feasible we don't want to deploy it until we get atmospheric CO2 levels back down to pre-industrial levels. To me space-based solar power should be regarded with the same suspicion as coal-to-liquids fuel.

Bob Wallace

There are two reasons to consider this idea.

1) Power would be available 24/7/365. No problems with the sun setting or cloud cover. No storage problems.

(I'm assuming the ability to relay power to other satellites which are in contact with the earth stations.)

2) Moving to this system would mean that we could take some of coal and petroleum plants off line, thus reducing our global warming blanket.

(Not that there aren't other legitimate reasons why this wouldn't work.)

Kit P

Good job Bob, you just explained why solar does not work,

“Power would be available 24/7/365. No problems with the sun setting or cloud cover. No storage problems.”

which explains why solar does not “mean that we could take some of coal and petroleum plants off line.”


Space based solar power shouldn't add any more heat to the planet than is released by the equivalent GWHs of fossil fuel power.

Bob Wallace

Good point about leaving that 'heat' in the ground.

We're using a somewhat inefficient source of stored solar power and producing waste heat in the process of making electricity.

Power "beamed in" would be largely pure power (I'm guessing).

Solar Systems

Great post.Solar Energy from Space is very amazing,truly an informative website.Thank for information....


hat's great that you think in this way there's many times that people get boring reading a book.

solar hot water

Transferring the sun rays and heat in to required form is know as solar energy. This is most frequently available solar energy resource. Installing solar energy system is convenient as compare to other energy systems. We can setup this for any size of residential or industry project.


I am not saying that this is an economical idea, but your numbers are a little off. A satellite with photovoltaic panels will receive sunlight 24 hours per day

Solar panels maryland

Well the solar panels can be called as a primary and only source of power for the satellite and we can't even think about the consequences if these power source was not there because the internet , long distance calls an gps will stop working by then

The comments to this entry are closed.

. .

Batteries/Hybrid Vehicles