An economist welcomes such methods as a way of achieving a stated goal (fewer net emissions) at lowest cost.
In theory biofuels produce low net emissions of carbon dioxide, since burning them merely recycles atmospheric carbon absorbed by the plant as it was growing.
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Some Latin American countries are already doing things to reduce net carbon emissions that put them ahead of governments elsewhere.
The U.S. is still No. 2 worldwide in net CO2 emissions, trailing only China, and is still No. 10 per capita.
Davis - that there's only a 2 percent difference in the net carbon emissions between ethanol and gasoline, which is virtually negligible - when the ethanol comes from corn.
It is renewable and it evokes credits in net carbon dioxide emissions, as well.
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This destruction of ecosystems which remove carbon from the atmosphere can lead to a net increase in emissions.
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The new regulations in Massachusetts, which will take effect in June, will promote smaller and more efficient combined-heat-and-power biomass facilities that require less fuel and have lower net carbon dioxide emissions over time.
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In net terms, emissions are likely to be much the same as they would have been without a significant shift to gas, provided that goverments stand by all the commitments they have made to curb carbon emissions.
The National Renewable Energy Laboratory estimates that the use of soybean B100, which is 100 percent biodiesel, in urban transit buses reduces net carbon dioxide emissions by 78 percent and reduces lifecycle petroleum consumption by 95 percent, which takes into account fuel required to cultivate crops, refine and transport the biodiesel.
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That has led the Manomet Center for Conservation Sciences to say that the net effect on greenhouse gas emissions is higher.
An attributional accounting protocol that relies on facilities-level GHG balances to report net CO2 uptake and track otherwise unregulated GHG emissions throughout fuel and feedstock supply chains.
His system has a design that makes it easier to get the air through it, uses cheaper materials and does not draw electricity from the grid, which adds to costs and reduces the net amount of carbon stored (since grid electricity comes with carbon emissions attached, from the fuel used to make it).
Jodie Marcyniuk, a transit priority engineer at Calgary Transit, notes that each of its transmitter-equipped buses saves 2, 000 gallons of fuel and nearly 50, 000 pounds of carbon dioxide emissions per year compared with buses on regular routes. (The calculations do not net out the extra gallons idled away by drivers on the cross streets.) "It works out beautifully, " says Marcyniuk.
Data shows that greenhouse gas emissions fell by 99 million tonnes of carbon dioxide equivalent (CO2e) during 2008, making a total net reduction of 627m tonnes of CO2e from 1990 levels.
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