Space-based solar power is a cool idea, but it's out of reach

What can the laying of the first transatlantic telegraph cable tell us about the likelihood that we are going to soon see electricity generated from solar power collectors floating about in space?

I ask myself the question because recently, I have been struck with the sense that at the time they were proposed, both initiatives seemed to be almost impossible.

Some background. Starting in the 1850s, efforts were made to put a roughly 3,000-kilometre-long telegraph line down on the ocean floor between Trinity Bay in Newfoundland and Valentia Island, Ireland. It took five attempts and nearly 10 years to create a system that really operated effectively.

It took a long time to lay a working cable because Murphy's Law, as applied to technological development, was in full effect: Wires continually broke, burned out or corroded, and picking broken lines off an ocean floor sometimes 3.2 kilometres deep was next to impossible in an age before submarines. Even success had an odour of failure: the first working line ceased operating after a few weeks, causing writers of the time to speculate that the whole enterprise was a hoax to spur stock market speculation.

The construction of space-based solar power sounds similarly difficult.

It entails sending up satellites to a spot 35,800 kilometres above the Earth. There, they are parked in a fixed orbit where they can always face the sun. Alongside the satellites are kilometre-wide fields of mirrored panels that redirect the sun's energy onto photovoltaic arrays. Since they are above the Earth's atmosphere, these rays are 25 to 35 per cent stronger than the rays that hit the Earth — not to mention that this sunshine is never blanked out by nightfall or storms, so you can have a constant supply of power.

The arrays turn these purer, more constant sunbeams into laser beams or microwaves. These are directed to power plants on the ground where their energy is turned into electricity.

Japan, California first to invest

Formal proposals for doing something like space-based solar power (SBSP) have been around since the 1960s, and both NASA and the U.S. Department of Energy evaluated them. The verdict through the 1990s was: cool as a concept but way too expensive and technologically challenging to consider seriously.

'Space solar power can solve our energy and greenhouse gas emissions problems. Not just help, not just take a step in the right direction, but solve.' —U.S. National Space Society

Now, people are looking again at SBSP — in no small measure because the world has become traumatized by fears of global warming and future energy shortages.

"Space solar power can solve our energy and greenhouse gas emissions problems. Not just help, not just take a step in the right direction, but solve," thunders the U.S. National Space Society's website. 

Linked to this are analyses saying that the costs of building and operating solar platforms in space are declining. In 2007, the Pentagon's National Security Space Office said, "a government-led demonstration of proof-of-concept could catalyze commercial sector development."

The coalescence of the need for sustainable energy and technological advances has created a recent flurry of activity in SBSP.

Earlier this year, the Solaren Corp. joined up with California's Pacific Gas & Electric Corp. in a plan that promises to provide 200 megawatts of space-based solar power to consumers by 2016.

At the beginning of September, the Japanese government, in conjunction with the Mitsubishi Electric and Mitsubishi Heavy Industry, announced that it was going to invest $21-billion US into building a 1,000-megawatt, four-square-kilometre solar power station. It would hopefully beam back enough energy in 30 years to power close to 300,000 average Japanese homes.

With the triumph of the transatlantic telegraph as a background, you would think that I should be counseling you to expect power from space in your lifetime.

I'm not.

No market advantage

What the telegraph story says to me is that space-based power is increasingly more likely to fail than to succeed. It's the market-timing paradox.

When the telegraph line was put in, its only competition was the transmission of information using ships. Sailing across the Atlantic took the better part of two weeks and led to the newspapers of the time often featuring stories with the attribution "a recently arrived boat passenger has reported." Conversely, once the telegraph line was actually functional in the 1860s, it could transmit Morse-coded accounts of events in minutes.

What this leap in the speed of information transmission meant is that there was effectively no competition for a telegraph. Accordingly, customers were charged $5 a word for the initial transmissions. To put this in modern context for you, when inflation is taken into consideration, that would translate into a 140-character internet tweet costing upwards of $4,000.

Therein lies the fundamental problem with space-based solar power: it isn't different from any other kind of electricity. Toasters or computers or the internet won't run faster or smoother or better when powered by solar energy from space. And this means that space solar power is — in price, reliability, availability and reduction of global warming — in competition with every other form of alternative and conventional energy.

It is as if laying telegraph cables existed in a world where primitive forms of radio transmissions and cellphones and internet signals were also developing. In this complex marketplace, price isn't set by a monopoly medium but by all media in competition. The most optimistic of scenarios today has space-based solar costing five to 10 times as much as traditional energy sources.

Prohibitive cost

The argument that proponents make is that a variety of technological advances could bring this cost down. However, there is a root problem in this. The same pressure to provide sustainable, environmentally friendly energy sources is at work through out the power industry. And Earth-based technologies have an intrinsic advantage in what is called "the learning curve." Jonathan Koomey, who co-authored in 2007 an article called "The Risk of Surprise in Energy Technology Costs," points out that when developing something like a better wind power generator, errors teach you things.

"You learn what went wrong, correct it and build another one," Koomey said from Yale University, where he is a visiting professor.

But space construction bedevils any simple learning feedback. Simply getting to where the problem exists to determine the problem and fix it is a huge issue. A single space shuttle flight costs about $1 billion. Even cheap launch vehicles envisaged for the future are estimated to cost around $78 million a flight.

How can you be nimble and do quick redesigns with this kind of overhead? I don't think you can.

And thus the paradox: if SBSP gets better but its competitors do as well, space power might never be good enough to compete in the energy marketplace.

So, what the transatlantic telegraph tells me is a great irony for proponents of space solar power. Despite all its recent activity and advances, SBSP seems today more likely to fail because external circumstances mean other energy alternatives are more likely to succeed.

Does this mean just writing off the notion of SBSP entirely and forever?

Even with this pessimistic analysis, I hope not. It is cool. It does have obvious advantages. It doesn't have the stop and go aspect of conventional wind and solar power generation. It doesn't use agricultural land as biofuels do. It doesn't have the waste disposal issues of nuclear. But I don't think that those advantages are going to count for anything until we actually do see how much Earth-based, non-global-warming-inducing energy generation we can produce.

And at what price.

In all this, I take my counsel from that unintended guru of technological development, William Shakespeare: "Ripeness is all."