This part of the article really caught my eye:
Current “use it or lose it” water laws don’t allow farmers to sell any surplus allotment, so they end up growing as much alfalfa as they can and selling it on the global market. Peter Culp estimates that 50 billion gallons of water—1.5 pulse flows—is shipped to China each year in the form of alfalfa, and even more to Japan. An open water market would allow both cities and environmental groups to pay farmers far more than they currently make growing alfalfa.
Terrible! The US West has been fighting water scarcity problems for 10+ years and we're exporting billions of gallons of water overseas?
There is also a new documentary out called DamNation which looks quite interesting. http://damnationfilm.com/
The theory is, that by ensuring we have a broad set of food stocks that we can potentially draw on should circumstances dictate, then we are capable of maintaining the basic elements of survival. (Energy Security is another one on the list - it's why we have aircraft carriers in the middle east).
Those farmers might be shipping Alfalfa to China right now, in the face of that thing called "Free Markets", but faced with a food stock collapse in the United States, it would take little more than a few strokes of the pen to require that same alfalfa go to American cattle.
Also, look at Upstate New York and Northern Pennsylvania if you are interested in food security. This used to be the grain basket of the country, but the farmland is all abandoned and reverted to forest, the hilly country is too difficult to farm with large machinery. But it's rain-safe, unlike further out west. I think in the face of climate change, farmland in that area is a most excellent long-term investment.
Couldn't resist. Not often alfalfa comes up in conversation.
A solar panel produces roughly (we're lowballing) 100 watts per square meter. Solar panels to produce 2 GW -- the power output of Lake Mead -- would cover about 20 million square meters, or 20 square kilometers. If we assume the solar panels only operate at capacity for a third of a day, that's 60 square kilometers. If we also assume that only half of the used land is actually light-capturing, that's 120 square kilometers.
Even under the most pessimistic of assumptions, solar still uses five times less land than hydro. Realistic solar installations would probably be significantly more efficient than I've assumed. Batteries are also significantly more space-efficient than hydroelectric storage.
I'm actually working on national-level hydro assessments at a national lab. We don't really predict more huge reservoir installments, but there is plenty of capacity out there. These set-ups (particularly non-powered dams) are also generally pretty cheap per kWh generated over their lifetimes (which in some cases reaches 70+ years).
Do you have wildlife issues to consider in the design? E.g., are the dams on rivers fish migrate up?
The badger hydroelectric plant in Wisconsin is 86 years old, and that's just one I happened to know because I collected data on it recently. If you go further east in the states and then across the Atlantic, the plants can get older than that as well. http://www.kaukaunautilities.com/about_us/default.asp?Catego...
EDIT: Oh, and in terms of cost, when planning out capital expenses most hydro projects are assuming a shorter lifespan than actual. I don't have numbers in front of me, but I feel like costs are generally accounted for a 20-40 year lifespan (weighted towards 20), although they do expect the plants to operate for 2-3x as long.
I'm guessing that is it's primary value. The power generation is secondary.
Is this really a common misconception? Has no one ever seen a dam? I can't think of any other form of energy production whose sole requirement is massive amounts of land to flood.
Brazil's debate on hydroelectric dams (and we have a lot of them) are solely bound on the flood areas and environment/habitat destruction they cause.
I really doubt that's a common misconception.
There are engineering concerns with waves and the usual problems anytime you mix water electricity and metal.
There are biological concerns where polluted water is already anoxic enough so blocking light is not going to help.
Still there's no inherent reason the land can only be applied to one tech.
Maybe if you have an infinite supply of cheap incredibly tall concrete pylons you could mount windmills too, although that's sounding unlikely.
Do you have any ballpark ideas about how the cost of producing the dam (most concrete, I guess) compares to the cost of producing 120 km^2 of solar panels + 'enough' battery capacity, in terms of some kind of ecological footprint?
My intuition is that the ecological capital costs of solar panels greatly exceed the capital costs of the dam, but I have little faith in my intuition....
But these usually flood a minimal area like 10000 square meters.
Public companies that develop hydro power projects annual reports is a good place to look for this type of information.
If it's important to you, let your legislators know, and vote accordingly.
I will be eating fewer hamburgers after reading this.