I copied this from Jerry Pornelle’s web site from his quick forum on corn and ethanol.
This is the first that I have heard of displacement hydroponics. I also find the 200 tons per acre a bit hard to swallow, however achieved.
What we need, I suppose is a completely new starch crop that can prosper in this hydroponic environment. Since tomatoes work so well, then perhaps we can do this with potatoes. The only modification would be to prevent any light getting on the roots. Potatoes are also a preferred feedstock for ethanol anyway. In fact, why the hell are we producing corn to make ethanol anyway?
Corn produces ten tons of stover to produce perhaps one ton of starch in the form of corn. The complete reverse will be true for potatoes. We must be crazy!
So a hydroponics operation producing 200 tons of potatoes per acre per year certainly competes with the current state of algae production.
It also strikes me that the bulk of the nutrients will be in the plant itself and open to recovery.
So a simple hydroponic potato protocol may be just the ticket for the mass production of ethanol. It should operate with a minimized water and nutrient loss while producing essentially pure starch on a fraction of the land demanded by any other protocol.
We may even breed a consumer version with non toxic skins as they will not have to fight the soil.
This all achievable right now and ethanol producers can start by encouraging potato crops with their local suppliers since the subsidy game is not likely to last long with all this recent heat. Even field potatoes are a better production deal than corn once you decide to buy starch. Half the acreage will produce as least as much as corn.
The only problem with potatoes is storage which is much fussier than corn.
Subject: corn, food, and ethanol
Hi, Jerry - first, thank you so much for printing the entire exchange. I think you fairly represented my views, and I greatly appreciate your doing so.
I had intended to follow your site closely this week, but my evil overlord masters - AKA customers - demanded that I actually work for a living. Hence I've put in about 50-ish hours in the last 3 days, and today I am both frazzled and out of touch. But let me touch on a comment or two regarding our discussion.
Jim comments that "food availability is decreasing because food is being diverted to fuel production". I would disagree with that assertion; in fact, food is plentiful. There have been no riots due to lack of food; the riots have been caused because the food, although plentiful, was too expensive to purchase. That is a very, very important distinction. I state again: There's lots of food on the shelves. There is no shortage of food. The problem is not the availability, but the price.
In the United States, we have lots of land that is not in production, simply because there is no demand for the food that it could grow. If ethanol production increases, I would expect that the quantity of land not currently in production would decrease; but until it hits zero, diverting food to ethanol production will have no measurable impact on food costs.
Bob Ludwick offers some figures regarding the water requirements of corn growing. Well, he's right, sort of; but you wouldn't grow corn in the desert the way its grown in Nebraska.
What you would do is grow corn using a displacement irrigation hydroponics system. The way I did this, to grow tomatoes in January in my apartment 20 years ago, was to start with a tray filled with gravel. Below that, I had another sealed container with the nutrient solution; and every hour, a timer would start a pump which would pump the nutrient solution from the lower tray up to the gravel filled tray, which contained my tomato plants. When the upper tray was flooded, the air between the gravel was forced out; and when the timer kicked off, the pump would stop and the solution drained back into the lower tray. This sucked fresh air back into the spaces between the gravel, thus providing oxygen for the plants (plant roots require oxygen, or they rot).
This proved to be an amazingly efficient way to grow tomatoes. There was virtually no water lost due to evaporation; all I needed to do was add a tiny quantity of water to the lower tray every few days. (I also added fresh nutrient solution).
In fact, most conventional irrigation - just setting up a great big lawn sprinkler, which is essentially the way commercial irrigation is achieved - results in 90% water loss due to evaporation. This is why drip irrigation systems are so dramatically effective at growing plants, yet use virtually no water. And displacement hydroponics systems are considerably more efficient than drip irrigation.
Here's a quick quote from an article on hydroponics in the desert, from a quick google search:
"Naturally, the weather is hot and dry. The average yield for vegetables in the field is about 5 tons for each acre used (85,000 acres in all). Yet in the greenhouse at Riyadh, the American company gets more than 200 tons for each acre planted! No wonder the Saudis are impressed and keep urging the Americans onto higher achievements."
You can read the article at http://www.mayhillpress.com/arabian.html . There are probably better sources of information, but I'm too crusty and burned out this morning to hunt for them.
We will need water to do a lot of things, including growing crops. And given the importance of water, we should shift over to hydroponics for all our food production. If we could save 90% of the water used for irrigation currently, it would take a lot of the load off our current water woes.
But more generally: we need to confront all our challenges with a positive, 'can do' attitude. If we stop, throw down our tools and quit every time we bump into a problem, we will die. We'll die as individuals, and we'll die as a nation.
But America is a 'can do' nation. Or at least, it used to be; just a few weeks ago I was going through some old black and white photos from my youth, and discovered pictures I'd taken of the screen of our television, as one of the Apollo moonships lifted off. With the American flag billowing gently in the foreground, in the corner of the shot - I stopped, and looked at that shot for a long time. It brought tears to my eyes.
Jerry, we were once a nation that could do anything. We've walked on the soil of another planet. We've sent probes to Mars, not once, but many times. We invented nuclear plants, and every watt of power generated from nuclear energy on planet Earth today, owes its heritage to American Ingenuity.
Surely to hell we can figure out how to grow corn.
Take care, my friend - Charlie
I did some experiments with hydroponics back in survivalist days. We used hand labor -- lift the buckets by hand to make the hydroponic fluids flow -- and got amazing crops of tomatoes, cucumbers, squash; indeed a lot of edibles from a small shed in my back yard. The structure was plastic tubes, heavy plastic covering, some netting to provide wind strength, and some nylon line to anchor the whole system. It did use electricity in that there was an exhaust fan. I wrote it up in both Survive Magazine and in A Step Farther Out, the Galaxy Column. Hydroponics farming gives a huge return on time investment, and most of the work can be done by minor children. In my case it was labor intensive, but not horridly so. The boys were able to lift the buckets twice a day (that was our schedule as I recall; I would have to find the log books from 30 years ago to be sure). But one thing is certain, we got a lot of fresh vegetables from it. Another certainty: it wasn't worth the effort to keep it up once Lucifer's Hammer hit the best seller list and we wanted the back yard for a pool.
I still have room for a hydroponics shell (a small one) and if it comes to a real crunch on food I'll look into that again. Actually the proper time to look into it is now. The equipment isn't cheap but it's likely to be really expensive if we go into depression times. A vegetable garden in your yard is already a reasonable investment. If you want a lot of yield, look into hydroponics. It worked for me anyway.
As to whether American ingenuity can use that technology to help win us energy independence, I have to say it again: cheap energy will cause a boom. The only cheap energy I know of is nuclear. Three Hundred Billion bucks in nuclear power will do wonders for the economy. We build 100 1000 MegaWatt nuclear power plants -- they will cost no more than 2 billion each and my guess is that the average cost will be closer to 1 billion each (that is the first one costs about 20 billion and the 100th costs about 800 million). The rest of the money goes to prizes and X projects to convert electricity into mobility.
Of course we won't do that. - jp