Grass in the tank - a native plant could help US energy woes

By Klaus Marre Jun 26, 2006, 4:00 GMT

Pittsburgh, Pennsylvania - US President George W Bush hopes that a grass that once covered tens of millions of hectares across North America could help the US kick its addiction to foreign sources of oil.

The plant, called switchgrass, looks nothing like grass in the traditional sense. It can grow up to 4 metres tall and has stems as thick and sturdy as pencils.

On their first forays into the massive plains at the heart of North America, European settlers found the tall plants spanning as far as the eye could see. But the grass rapidly gave way to corn, wheat and beans to feed the expanding movement, and to roads and cities.

In a twist of history, the grass once sacrificed for human food and space could soon grow again in vast fields to satisfy an even more pressing hunger for energy, if Bush, researchers and high profile investors have their way.

Most Americans first heard the term switchgrass in a major speech by Bush in January, when he proposed a ramped-up research effort into turning biomass into ethanol, a clean-burning fuel.

The ultimate goal is to replace petroleum-based petrol with pure ethanol or a mix of gasoline and ethanol. In that scenario, drivers with so-called flex cars would be able to pull up to a gas station and decide which kind of fuel they want to use.

The US government is not alone in investing more money into ethanol research and production. In May, investment bank Goldman Sachs put 30 million dollars into Iogen Corp., a Canadian company and leader in renewable cellulose ethanol technology.

Goldman Sachs spokesman Michael DuVally said his company saw the 'potential for an attractive return' on its investment, and with gasoline prices in the US at all time highs, other investors agree.

California-based billionaire Vinod Khosla, who has invested part of his personal fortune in ethanol technology, is an 'evangelist on this stuff,' said David Bransby, a professor at Auburn University in Alabama and an expert on switchgrass and ethanol.

For ethanol enthusiasts, Brazil is the holy grail, having weaned itself of foreign oil with a 30-year push to expand sugarcane production for fuel, now widely available and often cheaper than regular gasoline.

To date, most US ethanol efforts focussed on corn, a crop that experts say falls short of sugarcane's qualities because of the energy needed to grow it - in the form of fertilizer and cultivation - and its lower efficiency rating.

The ratings rank how much energy is contained in a fuel product per unit of fossil fuel used in its production. Ordinary gasoline has a 0.8 fossil energy balance rating; ethanol from corn, 1.5; ethanol from sugar cane, 8; and the emerging category of cellulosic ethanol, such as that from switchgrass, a range from 2 to 36, based on current experiments.

'Corn is not all that efficient as (an) energy crop,' said Scott Matthews, who teaches at Carnegie Mellon University in Pittsburgh.

In addition, corn production for ethanol cannot satisfy America's thirst for fuel. Currently, the US produces only 4 billion gallons of ethanol from corn - less than 3 per cent of its annual level of consumption.

The most optimistic production estimates are for 15 billion gallons of ethanol, but others say corn's potential has nearly been maxed out.

Although sugarcane is about five times more fuel-efficient than corn, it can currently only be grown in the south of the US, although sugar growers are exploring how to grow the crop further north.

That is where switchgrass comes in. Although its energy efficiency is uncertain, since it falls into the emerging category of cellulosic ethanol, it definitely outstrips that of corn, and has a number of other advantages.

As a native grass, it requires little fertilizer and is resistant to many pests and plant diseases, according to Bransby.

In addition, switchgrass is great at capturing carbon dioxide and trapping it underground with its three-metre deep roots, thus acting against the gas which is produced by burning fossil fuels and which many scientists say is the main reason for global warming.

Bransby hopes that switchgrass ethanol will be commercially available by 2012, as Bush proposed in his speech. There is more than 'just interest' in the topic, 'there is activity', the scholar adds.

He even sees soaring oil prices as a silver lining to the cloud, 'because it forces us to do what we should have been doing 20 to 30 years ago.'

In fact, escalating prices have created a sort of demilitarized zone for cooperation along the entire political spectrum. Conservatives are finally interested in alternative fuels to reduce US reliance on foreign oil, while environmentalists like the clean- burning qualities.

In Washington, lawmakers are beginning to take the subject seriously - although the US federal government is way behind countries like Thailand and the Philippines, where national governments are mandating increased biofuel use, or Brazil, which requires 25 per cent of its gasoline to contain ethanol.

Some individual US states, however, no demand some biofuel content.

Senator Kent Conrad, an opposition Democrat who has introduced legislation calling for a 40-billion-dollar investment over five years into alternative fuels and technology, has renewed the cry for enforced improvements in the fuel efficiency of vehicles as well as cleaner coal plants.

He is particularly enamoured of the switchgrass idea.

'Wouldn't it be great if the president, instead of looking to the Middle East, could turn to the Midwest, because we could help grow our way out of this crisis?,' Conrad said.