[QUOTE=sweeteviljesus]
There are those who call for significant public investment in alternative energy on the scale of the Manhattan or Apollo projects. I tend to object to this for various reasons, but what do you think about it?
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The DoE and DARPA already fund a variety of alterative energy programs at various levels. Putting more money out there may accelerate development, but there is no guarantee of a revolutionary leap in technology just 'cause you throw money at it. A government-controlled program analogous to the Manhattan Project or the Apollo Program may bring together a lot of talent and stimulate innovation, but frankly I don’t know that it is that sort of development, nor that there is currently the kind of sustained impetus to keep such a program funded across several Congressional elections.
[QUOTE=sweeteviljesus]
Also, with regard to passive solar design, that is all well and good for new construction but what do you do about existing homes? Plant lots of trees in your yard? Is this mainly a consideration for reducing future energy demand? Also, how would it effect construction prices? I know that there are lots of houses here in Texas that were built before central A/C which are comfortable in 100 degree heat, but they don’t build them that way anymore.
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Bulldozing those awful, homogenous subdivisions would be a start. 
Most new construction is designed specifically to use high volume forced air HVAC primarily for heating and cooling, and there is little that can be done to remediate that. However, one of the major problems is that many building codes restrict or prohibit construction methods that would allow high efficiency natural thermal regulation; updating these standards would be a start, since many of these methods integrate well with existing layouts. Estimates of construction costs vary; I’ve seen the claim that German Passivhaus buildings are virtually cost neutral; more commonly, 20%-50% is the rule of thumb depending on what methods are used. Part of the problem is that relatively few contractors are familiar with the methods used to build passively heated/cooled homes, so labor costs are higher even though the actual labor may not be significantly more, and any special materials may not be as readily available; both issues would presumably be resolved if such construction were more common.
[QUOTE=Chronos]
Anyone have the current figures for wind power? Last I heard, wind was the most promising of the alternate-energy options… Is it still?
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Wind power with modern high efficiency turbines is highly cost effective on an individual basis, often giving a return on investment within three years or less. Modern turbines are almost maintenance free and if installed properly virtually impervious to normal operating damage (i.e. high winds). The problem with wind on a large scale, however, is finding suitable geography where wind power is effective, locations where it doesn’t interfere with sightlines and sound, avoiding environmental impacts (i.e. bird habitats, pollination patterns), and of course the vast footprint that windpower takes up. On land, wind power is most effective when the geography funnels wind through a pass or valley to give consistant power. At sea, offshore wind farms can make good use of reliable sea breeze patterns, although again you have to be cautious about affecting littoral habitats and upsetting people who paid top dollar for their beachfront real estate. It may also be possible to capture wind energy on a microscale for localized applications (think nanoscale “windmills”, although they’ll look like nothing that a microscopic Don Quixote would charge at) this is more of an off-grid, portable energy application.
In short, wind is a good, cheap, essentially non-polluting, and mostly environmentally neutral impact energy source (unlike hydroelectric or tidal power), but it’ll likely remain a supplement rather than provide a majority fraction of energy needs.
Stranger