Originally posted by pavil
Are you sure it takes up large amounts of land? I know a group here in Michigan that has prospected (mapped and tracked) the wind speed of areas of
the Great Lakes and Eastern Rockies at a height of 100ft. The winds at that height are 7.4 to 11 m/s on average that high up. One 600 kW wind turbine
can produce conservetively 1,467,328 kW-h. This is based on actual data of 8,283 hours (94.5% of a year).
Well, a few things to consider. The US used roughly 28,421,000,000,000 kilowatts per year (or 97 quadrillion BTU, for our UK friends) in 2000.
It would take 19,369,220 fans, in an area that provided at least that much wind, to provide the energy needs neccesary for the US. The United States
itself boasts a mere 3,537,441 square miles. That means we'd have to have 8 or 9 fans in every square mile to meet the
current energy needs.
This doesn't even account for the fact that our need increases about 1-2% each year. By now, it would probably take 10 fans per square mile to meet
current usage. That's assuming every single fan got at least that amount of wind turn.
Now consider the wind-stealing effect of fans. You can't line them up exactly with each other, because the one in front steals the wind of those in
back. So you have to do a cross-hatch pattern, leaving enough space behind it for wind to build back up. Anyone here familiar with sailing can tell
you how the same concept works with "overbearing". I'm not sure what the distance is, but it is a decent amount.
Now, there are 1609.3 meters in a mile, and a 600kw fan is about 44 meters wide. This means that you have room for about 36 fans, in any square mile.
Using a crosshatch pattern to allow 3 miles worth of wind to build up again, you're looking at a max of 12 fans per square mile, which allows for
very little increase in our future demand.
So, even if people could deal with the eyesore of having a giant fan on every single city block (which, granted, is quite possible), by the time we
could blanket every square mile with these fans, we'd have already met the max energy capacity.
Between the physical limitations, wind limitations, relatively low amount of power generated per unit, and the enormous magnitude of effort required
for "upgrades", I honestly don't think there's any future in wind-power except for small, lightly populated cities.
Even small communities may not want to go this route, since usually one of the benefits of living in a small community is the unspoiled scenery. If
the scenery is ruined with fans, it loses the appeal. Even if it doesn't lose its appeal, somehow, the small town will eventually become a larger
town, or a network of towns, requiring yet more power.
So while I admit it
would be a possible alternative, within our current power consumption, if we assumed that:
1.) Power needs for the U.S. never increased further than about 100 quadrillion BTUs (if it hasn't already)
2.) The people would stand for a ruined landscape of fans across every single square mile of the US.
3.) The fans were around 99% recycleable. Otherwise, you're going to have to find a place to put tens of millions of broken or outdated fans, their
parts, and so forth.
4.) Every square mile receives a steady wind that averages out to the same level of power that you mentioned in your post.
I hate to be a doomsayer on this, but I can't ever see wind power taking up the slack for more than 5% of the total power demands, short of a major
holocaust in the U.S.
REGARDING TRANSPORTATION ENERGY
A very good point has been brought up:
We cannot assume the same source will power both transportation and our electricity needs. Additionally, we'll need to think in terms of transition
from the status quo, to the "new standard".
Let's look at transportation first, as it's probably going to be the hardest transition to make. There are anywhere from thousands to millions of
gasoline-powered automobiles in any given city, and throughout the city, an infrastructure designed entirely around delivering this type of fuel to
the automobile. Not only must you get hundreds of millions of automobiles to change, you have to change the whole infrastructure to suit the new
energy.
Thus, I believe that, whatever the "New Standard" fuel will
eventually be, the interim transition will need to be a similarly delivered
liquid source that can make use of the existing infrastructure for about 10-20 years. I say 10-20 years, because that's about how long it will take
from the time we decide on a "New Standard" and the time it can be implemented
as a standard).
It would also make sense to use as much of our byproducts of existing refinements as possible. Waste not, want not.
That said, it seems like the most likely source of "transition" fuel, before the New Standard will be biodiesel, as it requires the fewest
modifications, pollutes less, already has a board with lobbyists, and is a least-cost alternative for non-petrol fuels.
Our long term goals for the "New Standard", however, will depend heavily on the future of transportation itself, and unfortunately there's no way
to really know how big of an impact mass transit will have in the future, or even the prospect of aerial vehicles. However, if I had to hazard a
guess, if we stick to ground-based transportation, I'd go with electricity, supplied with some manner of high-yield rechargable battery or
track-wire.