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Relying on Renewables
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Making fuel from corn in Iowa
by Carol Hills
October 5, 2000

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If you were to chart the quest for renewable energy sources and compare it to the rise and fall of oil prices, here's what you'd find: the higher the price of oil, the higher the level of interest in alternatives. Right now, oil is selling at close to $30 a barrel, and while that's a lot lower than it was last month, it's still high. And so many countries are showing renewed interest in renewable energy. In the first story of our four-part series, The World's Carol Hills takes us to Iowa, where researchers are finding potential energy sources just about everywhere they look.

***

(open with sound of people talking in a room)

There's a lot of corn in Iowa...and here, on a table in front of me, is what's left over after it's been harvested. There are corn cobs, corn stalks, corn husks, and corn leaves. It's what energy specialists call biomass. Biomass by definition is anything of recent biological origin. So that ranges from trees to manure. Iowa State University engineer Robert Brown says Iowa's rich topsoil makes the state a veritable petri dish for biomass research. Here at a lab, in the middle of a cornfield, Brown and his graduate students are trying to turn raw biomass into energy.

(sound of a blower)

This is a gasifier which converts solid fuels like woodchips and cornhusks into a gaseous fuel. It's kind of like combustion, says research engineer Jared Smenk, but more efficient.

Smenk: Combustion is the oxidation of fuel. Typically you're using air, the oxygen out of the air is your oxygen source and than reacting the air with your fuel and the product then is heat. What we do with gasification is a partial combustion. We only burn or oxidize about 25 percent of the fuel. The heat that's generated from that partial combustion draws reactions which converts the gaseous fuel. So you end up with a combustible gas called producer gas.

Like natural gas, producer gas can be used for heating and power generation. In other words, Robert Brown is trying to turn biomass such as corn leftovers and prairie grasses into a useful form of energy. If he succeeds, Iowa could be sitting on an energy goldmine. But Brown says it won't be easy.

Brown: Nature did all the preprocessing of coal into a fuel that we can use. Here, the farmer and the engineer have to put more effort into getting it into a usable fuel form so that there is a lot more capital costs, a lot more manpower costs in getting it into an appropriate form.

Brown mentions coal for a reason. Currently, Iowa depends on it for about 90 percent of its electricity. And it's not even Iowa coal. It comes in on rail cars from Wyoming. So Robert Brown looks around and thinks: Coal is dirty. It releases green house gases and we pay to ship it in. Iowa is rich in biomass. And right now we're just throwing it away. Why don't we use it to meet some of our energy needs? Alas, there's an answer to that question...

Brown: The unfortunate economic state of things is that any of these biomass crops that you look at here are more expensive than coal. We can afford to ship coal from Wyoming to the state of Iowa and it's still cheaper than switchgrass that you grow in your backyard, for example. to produce.

In fact, processing biomass costs 3 times as much as coal. And that, in a nutshell, is the obstacle facing renewable energy in the United States. How do you not only make it, but make it competitive. Robert Brown's strategy: Find a few niche markets -- perhaps overseas -- and then put your efforts into getting the technology right.

Brown: Right now it's very easy to go to China and say, let's use your agricultural waste to generate a gas you can use for cooking because they have no alternative. They've used up most of their native wood supplies and so this makes sense economically for them now. We need to be able to look at more technologies in the US and say, we can compete, but it's based on developing the technology first.

About a hundred miles south of here biomass proponents are taking a somewhat different approach to competing with fossil fuels -- essentially, if you can't beat 'em, join 'em.

( sound of boiler inside plant)

Here at a coal-burning electric power station in Ottumwa, Iowa, plant manager Cythnia Lord leads me through a labyrinth of machinery, burners, and giant pipes.

Lord: These pipes are where the coal goes in. This is the burner corner. We've got seven levels of burners where coal goes in. And the switchgrass you can see down there, it's a blue pipe. That's where the switchgrass is gonna go in....We're going to attach a pipe to the back of that...

That's right -- switchgrass, which is native to the prairies. Lord's employer, Alliant Energy, is part of a project to try to make electricity greener substituting switchgrass for about 5 percent of coal

Lord: Right now we're just looking to test the feasibility and the economic feasibility of it. If it's not economically feasible, it's likely we won't be using it on a regular basis. That's the main purpose of our first test, to test the economic feasiblity of it.

Lord says if switchgrass is not economically feasible, Alliant Energy will drop the project. Jim Cooper, who runs a rural development organization says that would be shame.

This is such a large powerplant that a 5 percent substitution really represents about 200,000 tons of switchgrass use annually. Five percent doesn't sound like a lot but it is still a fairly significant piece So that's a five percent renewable source where none existed before.

One hundred and fifty miles northwest of Ottumwa you'll find more advocates of renewable energy. But instead of looking to the ground for an answer, they're looking to the sky.

Here, on Iowa's Buffalo Ridge, turbines are generating electricity from the wind. This is one of the largest wind farms in the world. Several hundred of these 300 foot wind turbines tower above corn and soybean fields. Unlike the switchgrass project, there's nothing experimental about this. When the wind blows, you can generate electricity. And it's cheap. At 3 cents per kilowatt hour, wind power is competitive with coal and natural gas. And yet, Ken Hach, of the Enron Wind Development Corporation, says American consumers are reluctant to switch off the fossil fuels and switch on the renewables.

Hach: We're very spoiled. We have a very good lifestyle here. When we flip a switch, the lights come on, when we turn the thermostat, the oven comes on, the air conditioning comes on. And we really don't want to change and we really don't have to with renewables. But we've been told that it is going to change our lifestyles in some ways, in the past, so now we're finding out that it's not going to be that change. Also, the United States doesn't have an energy policy. It's not a planned thing, it's a market by market thing.

Hach remembers a time when the United States was a leader in wind energy. But now some of his company's biggest clients are Denmark, Spain and Germany. Still, folks like Chuck Goodwin, remain true believers in the power of wind.

Godwin: I feel it's the wave of the future. I just think it's great for the country. It's going to give us cheaper energy some day.

Goodwin is neither a scientist, a policy wonk nor a Birkenstock-wearing environmentalist. He's a retired farmer who's lived on the same patch of Iowa earth since 1936. That land now has 3 wind turbines on it...in a straight line between rows of seedcorn.

Godwin: We're not going to have a bunch of holes in the ground to dig out oil, to buy oil from the foreign countries and pay their exotic price. This energy will be renewable and the money will stay here in the United States.

In fact, some of it is staying right here with Chuck Goodwin. That's why he agreed to have the wind turbines. Ken Hach's company pays Goodwin for each turbine the farmer puts on his land. And the more power the turbines generate, the more money Goodwin makes.

Godwin: We are guaranteed $750 per year, per turbine. And these 3 turbines on our property sits about on an acre and a quarter which is pretty darn good rent right there from the turbines. As it looks to me right now, I am anticipating $2000 a year from each turbine.

That's about $6000 a year, a healthy addition to Goodwin's annual income. All he has to do is take a bit of land out of cultivation. The turbine company does the rest.

On this farm at least, renewable energy makes good economic sense. And project head Ken Hach says, when more widely used renewables will make environmental sense too.

Hach: The best thing is we've become competitive at a time when people are really becoming concerned about CO2 buildup, the greenhouse effect Many many countries take it very very seriously. We in the United States don't.

Well, some people do. The Iowa legislature passed laws in 1983 and 1990 requiring utilities to purchase approximately 2 percent of their power from renewable sources, mainly wind. But it took 16 years of court battles with the utilities before the green power finally went on-line last year. Iowa's Governor also proposed increasing renewables from 2 to 8 percent of Iowa's power by 2011. The bill died in committee.

For The World, I'm Carol Hills.

 


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