Stories tagged greenhouse gas
Large scale study shows 540% net energy gain when ethanol is produced from switchgrass
Panicum Vergatum: Switchgrass
Courtesy U S Govt
Kenneth Vogel, a geneticist with the U.S. Department of Agriculture in Lincoln, Nebraska, and his colleagues, found that ethanol produced from switchgrass yields 540% of the energy used to grow, harvest, and process it into ethanol.
Their results, published online in Proceedings of the National Academy of Sciences, shows that switchgrass, farmed using conventional agricultural practices on less-than-prime cropland yields only slightly less ethanol per hectare on average than corn.
Farmers planted switchgrass on 10 farms, each of which was between 3 and 9 hectares. They then tracked the inputs they used--diesel for farm equipment and transporting the harvested grasses, for example--as well as the amount of grass they raised over a 5-year period. ScienceNOW Daily News
Switchgrass monoculture or mixed prairie grasses?
Anyone remember our Buzz post "Chalk one up for diversity"? David Tilman in that post is quoted saying, "diverse prairie grasslands are 240 percent more productive than grasslands with a single prairie species"
Now I read:
... Vogel says, is that yields on farms using fertilizer and other inputs, such as herbicides and diesel fuel for farm machinery, were as much as six times higher than yields on farms that used little or no fertilizer, herbicides, or other inputs to grow a mixture of native prairie grasses. ScienceNOW Daily News
Who is right? Can anyone explain why two reputable researchers are getting such different results?
Tags : New fossil evidence indicates that the ancestors of modern kangaroos walked on four legs, had fangs and climbed trees -- a sobering thought. Meanwhile, scientists studying marsupial flatulence have discovered that kangaroo gas contains no methane, and thus does not contribute to greenhouse gasses. A spokesman for kangaroos said he was glad no kangaroos were involved in changing the Earth's climate.
All hail to the beer fridge!: Canadian beer drinkers are destroying the planet, but having too good a time to notice.
Courtesy Brian Warren
Canadians love their beer. However, possessing only the standard number of kidneys (2), they must drink it slowly, and store it until they are ready. To keep their cold ones, er, cold, they have developed the tradition of the “beer fridge” – an old, used refrigerator, kept in the garage or the basement, and used just for beer and snacks. (Newer, nicer fridges go in the kitchen.)
But a new study by the Canadian government claims that this piece of native culture is wrecking the environment. The old refrigerators use more energy than newer models. Researchers have suggested buy-back programs, which basically amounts to taxpayers buying me a new fridge. Finally, a government subsidy we can all get behind!
There’s no reliable data on the energy consumption of the beer-launching fridge, clearly the greatest achievement in the history of civilization.
A study in Norway shows that an adult moose emits about as much greenhouse gas in a year as a car. Cows are even worse.
A new study found a link between human use of fossil fuels and an increase in the severity of hurricanes. The burning of fossil fuels has increased the level of greenhouse gases in the atmosphere, which has led to the warming of oceans in regions where hurricanes develop. The warmer the ocean water, the more severe the hurricane.
Pollution exchange: photo from Wikimedia Commons
Marketing pollution on the Chicago Climate Exchange
Most people will agree that something needs to be done about the pollution and greenhouse gasses resulting from our consumption of petrochemicals. One solution would be to encourage reducing emmissions by financially rewarding those that meet their quotas and penalize those that don't.
How it works
To illustrate, the American Electric Power's Mountaineer coal plant is America's single largest emitter of greenhouse gases - sending as much out from its stacks as Canada.
Last year the Mountaineer plant generated 10.5 million megawatt-hours of electricity, and a corresponding 8.6 million tons of CO2e. That would make its emissions, in CCX terms, a $39 million cost. If improvements yield just a 1 percent cut, the plant has almost $400,000 of emissions to sell. Looked at another way, the emissions are suddenly 20 percent of the cost of Mountaineer's fuel. CNN Money
The Chicago Climate Exchange (CCX) is the world’s first and North America’s only voluntary, legally binding greenhouse gas (GHG) reduction and trading system for emission sources and offset projects in North America and Brazil. Members make a voluntary but legally binding commitment to reduce GHG emissions.
By the end of Phase I (December, 2006) all Members will have reduced direct emissions 4% below a baseline period of 1998-2001.Phase II, which extends the CCX reduction program through 2010, will require all Members to reduce GHG emissions 6% below baseline. CCX website about page
AEP Mountaineer plant uses the CCX in three ways. If its emissions are below its allowance, it can sell the difference, meaning the company has an incentive to emit as little as possible. If it needs to emit more, it can buy the difference from another member. Or AEP can invest in an offset program - say, planting carbon-sucking trees - that would earn the company new credits. The goal of the CCX is to create a market for pollution that, in effect, becomes a mechanism for reducing it.
The cost to pollute has doubled in six months
The currency at the Chicago Climate Exchange is a Carbon Financial Instrument contract, otherwise known as a CFI contract. One CFI contract is equal to 100 metric tons of CO2. The price of a CFI unit was less than $1 in 2004, rose to $1.75 in Jan. 2006, and now (Aug) are over $4.
To see what Europe is doing
go to European Union Greenhouse Gas Emission Trading Scheme (EU ETS)
Corn field: Corn is used to produce ethanol fuels, such as E85. Photo courtesy killermart, Flickr Creative Commons.Biofuels are fuels that are derived from recently living organisms, such as corn or soybeans, or their byproducts, such as manure from cows. A recent study at the University of Minnesota examined the total life-cycle cost of all of the energy used for growing corn and soybeans and converting these crops into biofuels to determine what biofuel has the highest energy benefit and the least impact on the environment.
Corn grain ethanol vs. soybean biodisel
Two types of biofuels are becoming more visible as we look for alternatives to petroleum because of increasing gas prices: soybean biodisel and corn grain ethanol, such as E85. The study showed that both corn grain ethanol and soybean biodiesel produce more energy than is needed to grow the crops and convert them into biofuels. However, the amount of energy each fuel returns differs greatly. Soybean biodiesel returns 93 percent more energy than is used to produce it, while corn grain ethanol currently provides only 25 percent more energy than is used to produce it.
The study also compared the amount of greenhouse gases each biofuel released into the environment when used. Soybean biodiesel produces 41% less greenhouse gas emissions than diesel fuel while corn grain ethanol produces 12% less greenhouse gas emissions than gasoline.
Not a silver bullet
The researchers conducting this study caution that neither biofuel is ready to replace petroleum. Even if all current U.S. corn and soybean production were dedicated to biofuels production, it would still only meet 12 percent of gasoline demand and 6 percent of diesel demand, and we still need to produce these crops for food. Biofuels are steps in the right direction, however, and can be a piece of the overall puzzle needed to be put together to solve our energy needs.
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