I’ve been getting a lot of good comments on an earlier post about the viability of ethanol fuel. Many commenters seem to feel that corn-based ethanol is not a realistic long-term solution to our fuel problems, and it always seems to surprise them when I acknowledge that in fact, that’s true.

Corn-based ethanol cannot possibly become the primary, or even a primary, fuel source in the United States. The reason is obvious: even if we took every acre of arable land that wasn’t absolutely required for food production and planted corn on it wall-to-wall, the amount of fuel that would be produced would only be a fairly small fraction of the fuel we use. There just isn’t enough available land; plant-based fuels are relatively low in energy density and so you need a lot of plant feedstock to make a gallon of good fuel.

Why, then, should we be pursuing corn-based ethanol? The answer is simple: it is a bridge to an alcohol economy. Bob Zubrin’s excellent book “Energy Victory” lays out the case for transitioning the US to an alcohol-based, rather than petroleum-based, economy for our heating and transportation needs. He makes the case far better than I could, so although I won’t promise not to blog about it, I will forego the ten-page lecture for now. The bottom line is that the US can very easily become self-sufficient in fuel if we have an alcohol-based fuel economy, a self-sufficiency that we simply cannot attain with a petroleum economy. We should use our oil to make plastic, and use our staggering agricultural power as the basis for our fuel needs. At the very least, we need an alternative fuel source. 

But wait – didn’t I just say that we can’t do it with corn? Yes, I did. But right now, corn is the feedstock of choice for the ethanol technologies that we have. We have to start somewhere; it’s very difficult for both technological and economic reasons to just declare a full-fledged alcohol economy. The analogy I like to use is the development of oceangoing ships. We started with sailing vessels, which over time became larger, more complex, more powerful, and more capable. Eventually sailing ships became obsolete as wood- and then coal-burning steamships were developed – and for a long time, both sailing ships and steamships plied the same trade lanes. Coal-burners were in turn made obsolete by oil-burning ships, which used the same basic technology but which were much easier to refuel at sea and could go longer distances without refueling. Those ships were in turn made obsolete – although again, there are still plenty of them in the ocean – by nuclear-powered vessels that drew on the power of the atom and never need refueling.

In terms of the alcohol economy, we are at the sailboat stage. We’ve begun to develop the next generation of coal and wood-burners – but we’re still quite dependent on the sailing ships we already have sitting out at the dock. We still have to trade with countries overseas, and we can’t just shut down the trading economy while we wait for the steamships to get better – because the steamships will never get better if there is no trading economy for the researchers to sell into. We go to sea with the ships we have, and we constantly work on making the next generation better.

On Monday I’ll tell you more about why we need corn in order to get to the next stage of ethanol development.

In the last couple of weeks, I’ve talked about water and the unique role it plays in a modern agricultural economy. I mentioned how some nations without adequate rainfall have nonetheless developed thriving agriculture sectors, through the use of “fossil water” – water laid down and locked up thousands or even millions of years ago in aquifers - which countries like Saudi Arabia pump to the surface and use to irrigate strategic food crops, such as grain. That era is coming to an end, because the easily accessible aquifers are being drained dry, and fossil water does not replenish itself in the way that the normal water cycle provides.

In the immediate years to come, that’s probably good news for US farmers, because it means that grain and other commodity crop prices will be rising globally, without a parallel rise in American farmers’ cost of production. Irrigation is important to many US farmers, but most of our crops are grown with dryland techniques – they rely on rainfall, not engineered water systems, for the water every crop needs to grow. In addition, the irrigated crops that we do use don’t tend to use fossil groundwater – instead, we bring water from the natural water cycle to a new geographical location.

In the medium and long term, however, US agriculture may be facing a water crisis of epic scale. The reason is our old friend, climate change. Global warming alarmists are fond of claiming a stronger scientific consensus than actually exists, but regardless of the politics and controversies, there has been one constant in the history of weather and climate: it changes. It changes on the short timescale, and it changes on the long timescale. Northern Britain used to be a tropical forest. The Great Plains used to be a glacial tundra. Whether Al Gore is an idiot or a genius is irrelevant: we can predict with 100% certainty that our current climate expectations will be changing.

And unfortunately for many US farmers, one of the most commonly forecast change is a vast reduction in the amount of snowfall over the western United States. Unlike the eastern half of the country, which is well-watered through rainfall, the west relies on the snowpack to even out water flows throughout the year. Snow accumulates all winter, then melts and runs off all through the spring and summer – turning the Colorado River, among other vital arteries, into a huge torrent of water that is used for drinking and irrigation. Even modest warming can have an enormous impact on the west, because modest warming means rain instead of snow – and rain in wintertime does agriculture no good whatsoever absent some means of storing that water until it is needed. Snowpack provided that service for free – we can construct reservoirs, but the quantity of water involved is truly stupendous and so would be the expense.

The results of continued reduction in the snowpack could be very grim for western farming and ranching in general. Most farmers have water rights, entitling them to a certain amount of water from local sources and from rivers like the Colorado. But those water rights will not be worth much if the water isn’t there to fulfill the contract. Climate change could put a serious cramp in western agriculture’s style in the next few decades.

Next week we’ll see how the water problem is likely to affect agriculture worldwide.

I think our governments will remain virtuous for many centuries; as long as they are chiefly agricultural.

Thomas Jefferson to James Madison; December 20, 1787