News & Views item - June 2006

 

 

Two Caveats About the Production of Energy -- Choose Your Expert. (June 29, 2006)

    Following are two news items. On the left from the Journal Science.  On the Right from ABC News Online.

 

A Possible Snag in Burying CO2

By Richard A. Kerr
ScienceNOW Daily News
28 June 2006

Deep test.
Liquid CO2 in the tank truck pumped 1500 meters down was monitored at an observation well (foreground).
Credit: USGS

    Scientists testing the deep geologic disposal of the greenhouse gas carbon dioxide are finding that it's staying where they put it, but it's chewing up minerals. The reactions have produced a nasty mix of metals and organic substances in a layer of sandstone 1550 meters down, researchers report this week in Geology. At the same time, the CO2 is dissolving a surprising amount of the mineral that helps keep the gas where it's put. Nothing is leaking out so far, but the phenomenon will need a closer look before such carbon sequestration can help ameliorate the greenhouse problem, say the researchers.

Drillers often inject CO2 into the ground to drive more oil out, but researchers conducting the U.S. Department of Energy-sponsored Frio Brine Pilot Experiment northeast of Houston, Texas, pumped 1600 tons of CO2 into the Frio Formation to see where the gas went and what it did. "We're the first looking in this huge detail so that we can see what's going on," says geochemist and lead study author Yousif Kharaka of the U.S. Geological Survey in Menlo Park, California. He and colleagues found that the CO2 dropped the pH of the formation's brine from a near-neutral 6.5 to 3.0, about as acid as vinegar. That change in turn dissolved "many, many minerals," says Kharaka, releasing metals such as iron and manganese. Organic matter entered solution as well, and relatively large amounts of carbonate minerals dissolved.

The loss of carbonates worries Kharaka particularly. These naturally occurring chemicals seal pores and fractures in the rock that, if opened, could release CO2 as well as fouled brine into overlying aquifers that supply drinking and irrigation water. Perhaps more troubling, says Kharaka, is that the acid mix could attack carbonate in the cement seals plugging abandoned oil or gas wells, 2.5 million of which pepper the United States. The lesson is that "whatever we do [with CO2], there are environmental implications that we have to deal with," he says.

Geochemist Julio Friedmann of Stanford University is less concerned about corrosion eating away the seals on a sequestration site. "The crust of Earth is well configured to contain CO2," he says. He points to 80 U.S. oil fields injected with CO2 for up to 30 years. "We've seen no catastrophic failures." Nevertheless, the Frio results do "suggest an aspect of risk we hadn't considered before," says Friedmann. It is now obvious that if CO2 made it only so far as an overlying aquifer, he says, it could wreak havoc.

 

Related site

  • Frio Brine Pilot Experiment  (Requires Internet Explorer 6 or higher)
  • Wind farm industry a fraud: McGauran
      

       Thursday, June 29, 2006.
      
    9:30am (AEST)

     

    Peter McGauran ... says wind farms are not a cleaner alternative to coal fired power stations (Inside Business)

        The Federal Agriculture Minister Peter McGauran has attacked the wind farm industry, describing it as a fraud relying on taxpayer subsidies.

    Mr McGauran made the comments while addressing a group of dairy farmers.

    He says wind farms are not a cleaner alternative to coal fired power stations and should only be allowed in places where the community wants them.

    "Wind farms don't live up to the hype that they are an environmental saviour and a serious alternate energy source and the effect they can have on their neighbours are so serious it means they should not be allowed to get away with the exaggerated claims, their claims are fraudulent," he said.

    Mr McGauran says community concerns that wind farms are unsightly and cause property values to decrease should be taken into account.

    "These wind farms are not producing any electricity of any measurable amount and because they're having such an effect on rural communities, they should only be permitted where the community is firstly, engaged, and secondly, accepting of them."

    Susan Jeanes from the Renewable Energy Generators' of Australia says the comments are disappointing.

    "I suspect that it's better that we let the Environment Minister comment on matters relating to renewable energy and climate change and let the Agriculture Minister comment on matters relating to agriculture," she said.

    Ms Jeanes says the entire national electricity market was built with Government money.

    "Scientists around the world have predicted that we need to reduce emissions by up to 60 per cent by 2050, emissions from Australia's electricity sector are predicted to be at 250 per cent above 1990 levels by 2050," she said.

    "You can not do nothing and just sit back and just wait for a solution because it's not going to come without some form of assistance."

    Six hundred wind farms have so far been built or been approved in Australia under the Coalition Government.