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.