The boom in ethanol plants has also diverted resources, some of which, I would think -- like construction workers, welders, installers of monitoring instruments, etc. -- they would share in common.

Has anybody looked at this possible link?

These are only my personal opinions.

...I don't think they'd include ethanol in the study, Ron, sorry (a good idea for a study though, we should look into it).  Ethanol plants provide fuel for vehicles, but not so much for power plants.  I'm pretty sure the E85 and other standards doesn't apply to fuel used in gas powered plants, so it's effect would be minimal in that respect.

I'm interested in a cross-comparison between the construction costs for traditional power plants and wind farms of the same output though.

I'm not talking about the fuel, I'm talking about the construction of ethanol plants. These require skilled workers, and many of the components (like pipes, pumps, concrete) that are also required in the construction of power plants. If two industries are competing for the same inputs, that drives up prices.

These are only my personal opinions.

Having bought a lot of power gen equipment, I can assure you that ethanol is secondary (although of course, any manufacturing boom will drive up prices for associated manufacturing goods).  The big drivers are that (a) China and India are building massive volumes of power plants (far in excess of what we're building in ethanol and; (b) the US is concurrently entering a "build cycle" in the power fleet, as the old capacity runs close to full-bore and we have to build new generation to serve growing load.

Note though that these costs affect all power generation technologies, regardless of how "green" they are.  If you want to buy a generator (e.g., the copper wires that turn shaft power into electricity), you'll find prices are up about 2x from 5 years ago.  Ditto for steam turbines (the things that turn steam into spinning shaft power).  And steam generators. Thus, whether one is building a plant that is running on coal, biomass or waste heat, the construction costs are all up dramatically.  

Personally, I don't think this has a direct bearing on energy efficiency, since it hits all generators equally.  However, the indirect effects are strong - primarily because it makes the costs of all new generation sources more volatile, which tends to concentrate the attention on what we really want as a new generation source.  

The big efficiency story though is on the variable costs: higher fuel prices, and lower coal-plant efficiencies (due, paradoxically to clean air compliance) means that those plants have 2 - 4x the operating costs as they used to as well.  And on this metric, efficiency is a slam dunk, since it always lowers opex.

RON WRITES: I'm interested in a cross-comparison between the construction costs for traditional power plants and wind farms of the same output though.

According to the Union of Concerned Scientists analyst Steve Clemmer:

Renewable energy creates:

Nearly twice as many jobs as fossil fuels.  355,390 vs 197,910

$8.2 billion in income

$10.2 billion in GDP

... based upon a 20% by 2020 Renewable Energy Standard
Source UCS, Reviewing America's Economy, 2004, using EIA model.
Bob Gough