Transmitting energy in the form of microwaves, then converting them into electricity is enough to send a shudder throughout the copper industry. If it can be done to efficiently transmit solar energy beamed from space, it can just as easily be done to transmit electricity between any points on the earths surface - possibly reducing the waste presently experienced in transmitting energy?

The only advantage of much more expensive space based solar energy is that it would provide base load electricity free of GHG emissions. But then so do terrestrial based hydro, geothermal and nuclear, and they do it far more cheaply.

We can not ignore the fact that major advances have been and will continue to be made in both the storage and generation of electricity from solar energy produced on earth. It is even possible – though so far it has been glacially slow – that improvements will be made in the efficiency with which PVC’s convert sunlight to electricity.

Then of course, there is the question of vulnerability. Defending an earth-based power station with an array of missiles is more easily achieved than defending a PVC array and associated equipment in space. Remember the naught Chinese who flexed their muscles by shooting down one of their own satellites. That should have provided ample warning to strategic thinkers that it is not only communications satellites which are vulnerable.

In the end of course, it all comes down to the relative cost of the electricity generated free of GHG emissions and delivered to the consumer. If a PVC array in geo-stationary orbit can do it cheaper and with equal reliability, it’s a winner! However, nothing in the article suggests that this is at all likely.

On the other hand, development of the technology to improve transmission of electricity is a definite attraction and well worth pursuing

Nice idea but the devil is in the detail. First off the power station in space concept would be hideously expensive - billions of dollars to gain a few dollars worth of electricity.. then you have the huge problem of getting the electricity down from space.. microwaves will do but high voltage transmission using microwaves is an unknown area. the problems include the link between space and the receiving dish. What happens if the link is lost at the beam - thousands of megawatts - starts drifting across the countryside. Study the issue by all means, but don't expect too much..

Interesting idea, indeed. I remember reading this sort of stuff in the 70s.

Certainly it will be hugely expensive to build, but surely like many massive infrastructure projects like this, the initial expense is pretty much a once-off?

Consider the "space elevator", an idea first put forward by Arthur C. Clarke, which has been shown to be technically feasible. Sure, it's expensive - around the cost of the First Gulf War - but once built, the payoff in cheap access to space is immeasurable.

Mind you, I wonder how long it would take for Orange Bellied Parrots to show up in space? ;)

Will someone calculate the energy required to build the throw away launchers and the fuel needed to get the many satellites into orbit and then work out the payback period.
It will probably use more energy than the satellites will ever produce.
Then factor in the pollution generated by building the launchers etc. and in producing the fuel. And include the burning up in the atmosphere of the launchers and the waste of resources that are used in their building.

Really thought provoking article. Can see some technology challenges but it gives the lie that the earth is a closed system.

Peter A is representative of the green doomsayers - tedious.

Cheryl - sorry but PeterA has a point... to build something decent would require a very substantial effort consuming a great deal of energy. This is not about the pollution but about the energy consumed. Nor would it stop after the intial construction. Something that complex would probably require occasional maintenance visits and even refuelling (yes, satellite have their own fuel supplies - so they can undertake limited orbital corrections).. an noted, interesting idea but not likely to come about.. pity.

For a satellite to provide power to South Australia only.

1. Up to 80 launches required - one a month would take a few years and from where.
2. Fuel 500 tonnes or more per launch, will kerosine be available in decades time with peak oil?
3. Cost 400 billion dollars plus at todays prices.
4. No commercial launchers are available.
5. If it is in GEO orbit it would be beyond the ability to service, that is if there is a new craft able to take passengers into orbit. And it will need service.
6. If in LEO then it will need service as susceptible to damage to its large (very large array) from debris.

Now scale it up to meet Australia needs then the worlds.

This project (for SA only) would be on a scale that is beyond anything we have done to date and dwarves the space station and flying to the moon by magnitudes, could SA afford it?

This type of project is decades away and there are to many technical unknowns to be able to predict if it would pass a cost benefit analysis and an EIS.

The project is dependent upon PV’s to give us 24 hours power they could be installed on the ground with twice the size/capacity and the extra could be used for storage for later use (overnight).

The idea has been around for forty years and does not seem to have progressed very far which may indicate that no one really takes it seriously or even think it is practical.

I am an optimist in that we can fix this world but pessimistic in that politicians (big business) will prevent it happening.

Cheryl so you cannot answer my questions or comments and do not like the facts and have to drop down to a level to call people names - pathetic.

Just another thought - the energy received in the aerial has to be converted to electricity there is a loss in this conversion of about 20% which has to be dispersed to the local environment.

This loss will be in gigawatts for each installation.

This power, generated in space, is then transferred to the earth is extra heat and we already have a climate change problem.

Far better to have the solar power generated on the ground even if the installations are larger.

Space based power stations could be a reality within 10 years.

NASA however is constrained by Big American Business to Big American rocket techology. For the last 40 years we have seen this paradigm fail over and over. The world is far poorer in space advances than it was in 1973 as a result.

All we have from America is the gift to the world of Democracy-on-a-string and the Wall Street lift-pump that sucks real dollars out of new democracies with every rise and fall. It just $pumps & pumps into US consolidated $revenues. There is NO incentive in the US to make great strides in space. Nor will there be while oil companies like EXXon and the Peabody coal giant rule US space&foreign policy.

Its time to get unmesmerised from good 'ol yankee know-how and think for ourselves.

As an analogy, think of sending 100MB of internet data in one chunk across the Pacific. It can't be done. The internet splits it into 1KB chunks and sends them to all points of the compass along networks of servers till they meet up and get reassembled at their destination. Any 1Kb errors checked can quickly be resent and slotted into the file in real time probably via London or somewhere.

The same holds true for space. The impossibility of Big Rockets is palpable. The era of networking space by sending small packets of materiel via networks of "Server" platforms on Earth, LEO, GEO, L4/5 stationary points, the Moon and the inner planets is at hand. The servers themselves are just files of materiel and data, so they too can be auto-robotica-assembled.

IF Australian's think for themselves & get off the Americana Merrygoround we just MIGHT network our way to the moon using a 50-500Kg packet size over the next 10 years. Its about smarts, NOT Heavy Lift-Heavy fail.

Let's EXCEL-in-space. Let's DO IT.

EG.10Kg dynamo-module auto-connects to gas filled origami-fold-out-heat exchangers. 100 of these auto-assemble & align to the Sun in LEO..Instant Power station.

It's still cheaper to have solar down on Earth even if we need 4 times as much of it. Now, if the transmission part works as well as advertised we could build a global grid and beam Aussie solar power up and around to, say the US or Europe. I'm not altogether convinced.

Send a cable down from the satellite.
I recall an interesting calculus problem concerning this in the '60s. My Physics lecturer was convinced that a satellite with a cable was viable. I have no reason to doubt it.

Yes Precillian, a much more sensible idea.
Would those promoting the microwave idea tell me what the path loss
would be in decibels ?
Once we know that we can tell you how many times greater the transmit
power will be to obtain the desired power on the ground.

My guess is between 2 million and 10 million times the power.
So if the design was to produce 200 Megawatt on the ground, the transmit
power would be 400,000,000 Megawatt !
Where do you think you could get that sort of power amplifier at micro
wave frequencies !

Come in Dr Who.

The proven efficiency of power transmission between a microwave source and its rectanna is 85%.

Look it up!

This method of power transmission of course has other benefits. if you live near the beam you can take your frozen chicken dinner there and have it cooked in 2.5 usec.
Be careful to keep your hands out of the way.