[ExI] power satellites

[Tom Nowell]

Keith wrote:

"If that's the way you feel about it--without doing the hard work of 
looking at a design to cost engineering effort--that's ok.  In which 
case, what do *you* propose to supply the cubic-mile-of-oil per year 
energy the human population needs to avoid famines and resource wars?

The next best seems to be some 10 to 20 thousand nuclear reactors."

Well, I'd reckon the most feasible solution is the combination of a couple of dozen small partial solutions. The problem with the powersat solution is that it requires one big, solid financial commitment that must be reliably maintained until it is seen through to completion. To avoid Space Shuttle/International Waste of Space Station/ anything the USAF has commissioned in the past few decades/ anything the UK military has commissioned since 1980 problems, you need to avoid having design changes and major shifts of focus half way through.

Few bodies can afford the $350 billion price tag by themselves. Even if the US govt did back it, there would be a moderate chance of the next set of guys voted in either messing around with it or cancelling it. Big international projects like ITER and some ESA projects have shown that multinational projects can succeed, but it takes quite a few years of negotiation for everyone to agree on the share they're paying for, and where the major construction work is done.

So, without the single mega-project how do we get enough energy? Well, there are a lot of small partial solutions, many of which can be innovated by a single country, and when it is shown to succeed others can copy. Nuclear fission may work - the pebble-bed designs of South Africa may offer a way to burn the world's plutonium stockpile while producing small-scale needs, and didn't someone mention on this list a Japanese company's design for a reactor suitable for a community as small as 2000 people?

Market interference by governments could help - eg a requirement for utilities to buy a certain percentage of their energy from certain sources, this has worked for German solar power. Politicians would love this because it's not a direct tax that people would notice, it would just gently shove up people's utility bills (which get increased every year by the power companies anyway, regardless of general inflation rates) in a way the voters may just shrug their shoulders about. It provides an incentive to improve power generation technology through private sector investment.

Increasing the energy efficiency of infrastructure can help, and given the current rhetoric for spending our way out of recession by investing in infrastructure I can see this being sold politically - investing in US railways to ship US agricultural produce to world markets while using less oil will help keep the world fed while spending money now on employing workers.

Governments making a token gesture to public appeals to raise foreign aid could use their extra funding to invest in agricultural improvements in poor countries which minimise fossil fuel use.

I could keep going on, and mention funding OTEC for Hawaii and then exporting it around the globe, new transport alternatives, all the different solar/hydro/geothermal schemes, all the biotech schemes, and the rest, but there are lot of things that can ameliorate the problem. None of them will solve the problem single-handedly. Most won't even solve the problem even in combination with one other technology. However, given the combination of technologies and social policies and wise investment, there are many routes to success.

Don't get me wrong, I'd love for solar powersats to be a reality - I have a great love for schemes involving space, and deeply desire truly low-cost launches to orbit. The power satellite industry would form a colossal market that would force the price of space access down dramatically, and in doing so revolutionise our civilisation. I just wish there was a way of selling this that didn't seem too far beyond what projects we see today.

Tom