Feeds:
Posts
Comments

Posts Tagged ‘CO2 emissions’

While we’ve all grown accustomed to seeing the words “natural”, “healthy” and “environmentally-friendly” thrown around in advertisements for a variety of consumer goods, it’s important to remember that household items are not the only things capable of being greenwashed – case in point, natural gas.

The word “natural” has been used to connote things such as ‘green’, ‘healthy’, ‘non-toxic’. Many people’s cursory understanding of natural gas is that if it’s “natural”, it must be good, right? Unfortunately the truth about natural gas is more complicated. While it is true that natural gas emits far less CO2 than coal upon combustion, there are a host of other ‘fine-print’ problems that come along with the switch, most notably, fugitive emissions.

Leaky pipes and valves allow methane, a powerful greenhouse gas, to escape into the atmosphere.  Photo by Kevin Moloney, NYT

Methane, a powerful greenhouse gas, escapes from wells and leaky pipes and valves into the atmosphere.
Photo by Kevin Moloney, NYT.

Fugitive emissions are the emissions not intended to take place and that usually result from pressurized equipment leaks. While these leaks are relatively tiny, when expanded to a large enough scale the amount of methane being leaked into the atmosphere can have a large impact on climate. While the EPA originally reported that average leakage rate in natural gas production was somewhere around 1.5%, a collaborative study by scientist from several universities and government agencies released this past October revealed that the figure should be much closer to 3%. Even worse, there have been reports of methane leakage upwards of 12% at some production sites.

Many climate change mitigation plans focus on reducing CO2 emissions, but methane and its effects should not be overlooked. The IPCC has reported that over a 100-year period, methane is 35 times more potent of a heat-trapping gas than CO2. When looking at the effects of methane over 20 years, this figure jumps to 87. Suddenly, that comparatively small amount of methane being leaked out of wells, pipes and valves is incredibly important. In other words, 1 ton of methane being released into the atmosphere has the same heat-trapping effect over a 20 year period as releasing 87 tons of CO2.

20 Year Climate Impact of Natural Gas vs CoalWhile the CO2 emissions from burning natural gas are about half what is produced by burning coal plant to produce the same amount of power, after accounting for fugitive emissions and converting leaked methane into CO2 equivalent (using the IPCC 87x factor referenced earlier), natural gas climate change impact is almost as bad as coal.

(more…)

Read Full Post »

algae-open-pondChlorella sp. is a species of algae that has a significant proportion of fatty acids to its body mass. For humans, this can be a problem. But, in a world needing more clean energy, fatty biomass is considered a promising option by many scientists and engineers.

Why algae? Algae can grow in a body of water almost anywhere. We don’t need to use any of our precious farmland to grow it. Water conservationists may initially be concerned, but a group of scientists found that Chlorella sp. thrives in our waste water. Not only that, it cleans up the water, removing ammonia and a host of toxic metals. According to their report, the algae could be used to help clean up waste water at municipal water treatment plants then harvested for biofuels.

graph_algaeI had a chance to speak with Dr. Martin Poenie, Associate Professor in Molecular Cell & Developmental Biology, at The University of Texas at Austin. The Poenie Lab is helping to develop a technique for harvesting the oils from algae that could greatly reduce cost. Dr. Poenie also told me algae can be a significant source of phosphates, which we use in fertilizers. One of the most significant things about algae biofuels, is their small carbon footprint and high energy content. CO2 is sequestered during the growth phase of the algae and it is not released until the fuel is burned. On the whole, biofuels from algae look promising, and the variety of products that can be derived from it will make algae farming even more profitable.

Texas could do more to capture the energy and job benefits from this home grown energy source. Texas Legislature should act to strengthen renewable energy goals. HB 303, SB 1239, and HB  723 would all be good steps in the right direction.

Read Full Post »

We have known for a long time that CO2 emissions are absorbed by the ocean.  This is actually a very, very good thing, or else we’d have warmed at least 5 or 6 times as much as we have.

The problem is basic chemistry.  When you add CO2 to a water solution (or a salt water solution), you create carbonic acid. Though a weak acid, increased carbonic acid has already affected the ability of coral to reproduce and lowered the ocean’s pH by .1 points.  Under a business as usual strategy, this could increase to .4 or .5.  While this may not sound like much, that’s about the same as going from fresh water to the pH of soda.  Anyone remember the elementary school science fair project where you dissolved a tooth or a penny in Coca-Cola?

And now scientists have found that increased acidity harms other forms of marine life, specifically, THE CLOWNFISH.  A report from the National Academy of Sciences has shown that acid levels disrupt the clownfish’s olfactory sense (smell) which could leave them lost at sea.  Nemo!!  No!!!!

Read Full Post »