Wednesday 3 July 2024

The Engineer's Story

Poul Anderson, "Hiding Place" IN Anderson, The Van Rijn Method (Riverdale, NY, December 2009). pp. 555-609.

CS Lewis called hard sf "the Engineer's Story." Some of us just read past technical details. Here are some examples. Technic civilization taps converters directly with stepdown methods. Lacking such methods, the Eksers run a large generator with a heat exchanger, drawing A.C. from it. They pass A.C. through copper oxide rectifier plates to get D.C.

Technic civilization uses a light element converter which develops electric current directly. Ekser power plants might utilize heavier elements with small positive packing fractions. This was found to be impractical on Earth but maybe the Eksers are better engineers. Such a system would require less refined fuel which would be advantageous when visiting unexplored planets and maybe:

"'...enough to justify that clumsy heat exchanger and rectifier system. We simply don't know.'" (p. 588)

I don't know, either. In fact, I am no wiser than when I started to write that summary. We know which sf writers have had a scientific education.

7 comments:

Sean M. Brooks said...

Kaor, Paul!

I still see the "Eksers" adopting some types of Technic engineering tech as more convenient for their needs. With Old Nick brokering that for a "modest" fee!

Ad astra! Sean

paulshackley2017@gmail.com said...

I will shortly travel to London.

Sean M. Brooks said...

Kaor, Paul!

Have fun!

I'm expecting the Labour Party to win a majority in the Commons. Oh, well!

The Tory wets have only themselves to blame. They angered and alienated millions of Conservative leaning voters. Hence the rise of Nigel Farage Reform Party.

Ad astra! Sean

Jim Baerg said...

I think I see what Anderson was thinking & writing about.
Technic civilization is using something like the proton-Boron-11 reaction, which puts out all the energy as charged particles so conversion to DC electricity is close to 100% efficient. They might have something better than early 21st century tech for getting from the *high* voltage DC that would produce to AC or DC at whatever voltage is most convenient for the application

The Eksers are using some nuclear reaction that can run on easily available stuff, put just generates fairly high temperature heat, like current fission reactors. So the heat is turned into AC electricity with some sort of heat engine, turning an AC generator, efficiency probably <50%. Their electric technology is equivalent to early 20th century earth, thus if they want DC at a given voltage they use a transformer to get AC at the desired voltage and the copper oxide rectifier, rather than something like current high power rectifiers.

I vaguely remember looking up "copper oxide rectifier" on an early rereading of the story and finding that tech was made obsolete by the silicon diodes of mid to late 20th century power electronics.

I guess the main point is at least some Ekser tech was inferior to what Van Rijn was accustomed to.

Sean M. Brooks said...

Kaor, Jim!

Thanks for some interesting technical comments. I thought, from a History Channel program about Thomas Edison and Nikola Tesla, that the AC electronics developed by the latter was superior to Edison's DC system.

Ad astra! Sean

Jim Baerg said...

Until fairly late in the 20th century it was hard to turn DC into AC.
However, it is easy to turn AC at one voltage to AC at another voltage, and then turn the AC at that voltage to DC at that voltage. All at fairly high efficiency. That copper oxide rectifier BTW is lower efficiency than the silicon diodes currently used.
Look up 'rectifier' for AC to DC converter, and 'inverter' for DC to AC converter.

High voltage and low current electricity can be moved long distances with much less loss of energy to heat than low voltage high current electricity, but the latter is easier to use for many applications. So the easy conversion between high & low voltage (look up 'transformer') is the *big* advantage of Tesla's AC system over Edison's DC system. Then until reasonably efficient inverters were devised it was better to generate AC & convert to DC only when the application needed DC.

The copper oxide rectifier was a plot point because it would destroy itself in a hydrogen rich atmosphere, which eliminated one of the possible 'zoo animals' as the owners of the ship.

For a somewhat similar 'Why are the aliens doing it *that* way question' as a major plot point in a story:
There was a story in Analog a bit more than a decade ago, in which a radio signal is received from a nearby star, asking for an exchange of technological ideas. The aliens send data about their best fuel cells and ask for any improvements. Their fuel cells are better than anything humans have and humanity is wondering "How can we reply so the aliens think it is worthwhile to send more such information".
The solution comes when someone looking at the instructions for sending the reply, notices that the method seems rather kludgy, and then has a rather 'Andersonian' realization that "Oh they don't have solid state electronics. They are using vacuum tubes etc." So humanity's reply is "Thank you for the fuel cell tech. This might interest you" Then instructions for making 1950s level transistors.

Sean M. Brooks said...

Kaor, Jim!

Many thanks for these very interesting technical comments. And the ANALOG story you cited reminded me of how, as so often, Anderson also wrote a story touching on how to communicate with aliens, "The Word to Space." The twist in that story being how difficult it was for humans to exchange scientific information with these non-humans, due to them being ruled by an Iranian style theocracy not interested in such things. And it was a Catholic priest and scientist who suggested a way of subtly undermining the theocracy.

Ad astra! Sean