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Comment by Eduard | Hacker News Reader

At night, Germany's solar power equals 0 nuclear plants.

Wrong. The energy from solar power can be stored in water reservoirs and that water can be used at night to generate power.

At night the demand for electricity is significantly lower.

Germany is developing the whole range of renewable energy including new storage options.

Not just solar.

That's true. Fortunately: (1) it's always sunny somewhere (2) we are increasing our ability to store power (3) industrialized countries use less power at night.

His point is that if one depends too heavily on solar, there are times when they'll have no access to power. How does one transport solar power from Japan to Germany?

You don't. Instead you add wind and storage and quick-cycling natural gas.

You put mirrors in space.

But seriously, solar power generation by huge space stations that beam the power down to earth, then use mirrors to feed it where it is needed.

I think it's been shown that it's infeasible. You'd lose too much power in the beaming process, or you'd have a death ray beam that destroys anything that flies between it... you could increase the area, but then you'd need a collector dish the size of montana.

The best idea might be something like in the movie Moon where the power is stored chemically, then shipped back to earth.

We actually already have energy-storage technology (in your macbook, too!) - it's just terribly inefficient.

I think the most common technology in use today at powerplant-scale is the "Pumped-storage hydroelectricity plant". You basically pump water uphill when you have energy - and let it flow downhill again, through your energy-producing turbines, when you need it back.

Either way, there is tons of research in this area (e.g. SmartGrid). It seems like a problem that we will solve eventually.

Energy-storage technology isn't inefficient. Energy-storage technology is expensive.

"Efficiency in general describes the extent to which time or effort is well used for the intended task or purpose."

Comparatively high cost is the main factor why it is still be considered less efficient although that is slowly changing.

If you go on to the next paragraph in the wikipedia article you copy-pasted without citation, you'll see "The term "efficient" is very much confused and misused with the term "effective". In general, efficiency is a measurable concept, quantitatively determined by the ratio of output to input. "Effectiveness", is a relatively vague, non-quantitative concept, mainly concerned with achieving objectives."

Your post consists almost entirely of factual errors:

You'd lose too much power in the beaming process

http://en.wikipedia.org/wiki/Wireless_energy_transfer#Microw...

"Rectenna conversion efficiencies exceeding 95% have been realized."

Here's another experiment that achieved 84% efficiency. http://en.wikipedia.org/wiki/Space-based_solar_power#Microwa...

you'd have a death ray beam that destroys anything that flies between it

http://en.wikipedia.org/wiki/Microwave_transmission#Common_s...

A bird flying above a rectenna on actually proposed designs would feel warmer and keep flying.

but then you'd need a collector dish the size of montana.

There are no collector >dishes< involved, as far as I know, rectennas don't need a parabolic reflector. Parabolic dishes add directionality, but increasing the effective aperture is a better design for power receiving. Proposed collector area is typically on the order of one or a few squares mile, which compares favorably to the footprint of existing power generation schemes.

The best idea might be something like in the movie Moon where the power is stored chemically, then shipped back to earth.

The power wasn't stored >chemically< in the movie.

somewhere... I'm living at north of NRW, and this spring wasn't sunny at all - only last week was sunny here, while 3 first week of May were rainy :-(

Actually at night it equals 10 :)

This is not a fair argument. When a nuclear reactor is being inspected, re-stocked, checked, repaired, refurbished, its output equals zero solar panels.

Fukushima's output has been equal to zero solar panels for over a year, despite its incomparably greater cost.

The amount of time a nuclear reactor is offline for inspection, refueling, repair, etc is far less than the amount of time it is dark.

But nuclear plants burn fuel at night when nobody needs the energy. Pumped-storage hydroelectricity is needed for both.

The sun burned fuel for billions of years well there was no one around whatsoever.

When it by earthquake/tsunami I know which plant I'd prefer to be near. The pacific rim would not seem ideal for nuclear power.

Which?

http://www.reuters.com/article/2011/10/20/us-japan-nuclear-t...

Most of those things are by-design made to be sturdy as fuck. And so far, no-one has died from Fuku-radiation?

Japan has 50 reactors. That's an investment of more than 100 billion dollars.

Currently none of those is operating. Several of them will stay shutdown.

The clean up of Fukushima is costly.

That's a huge economic loss.

OTOH most of the other power plants (i.e. non-nuclear) are running.

Are you joking? The area is unsafe, and it seems it will be for a fair while. Guess you don't know anyone who has been evacuated.

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