Tag Archives: energy

Plastic from algae: How green?

Plastic from algae: How green?

Posted by Evan Beach at May 18, 2010 08:30 AM | Permalink

A story in Discovery News on new algae-based plastic highlights green benefits but misses the challenges.

ShareThis

An article in Discovery News offers a rare look at how algae can be used to make something other than fuel or animal feed: plastic.

The story would have been more informative if the reporter had discussed the challenges that remain before algae fuels or plastics can become widespread. It is still not clear how algae can be produced sustainably on a large scale.

Reporter Alyssa Danigelis describes a new plastic that can be made with up to 50 percent algae. The company developing it hopes it will be 100 percent algae in a few years. Danigelis draws attention to the major green benefits of this new technology: it uses what would probably be a waste material from biodiesel production, it should not have any impact on the food supply, and further research and development could lead to a compostable material.

The 50 percent algae product also contains polypropylene (PP), a plastic often encountered in everyday life, for example, in microwaveable food containers. Such blends of natural and synthetic materials are not completely biodegradable but they often help to reduce consumption of limited resources.

By using algae left over from fuel extraction, this new plastic supports the idea of a “biorefinery.” The oil, coal and gas industries don’t just produce fuels – they produce the chemical building blocks for everything from industrial solvents to pharmaceuticals, leaving almost nothing to waste. Similarly, biofuel production will be more competitive if all of the raw materials are used productively. Plastic from algae is a step in that direction.

However, water, nutrient and energy demands can be extremely high and these issues are just as serious as whether the technology will compete with food production. Until the science is worked out, the “greenness” of algae – beyond its actual color – is not yet certain.  The story could have made this more clear.

New energy source discovered?

New energy source discovered?

Posted by Adelina Voutchkova at Mar 16, 2010 09:50 AM | Environmental Health News

A CNN report on a “new energy source” needs scrutiny and more explanation so readers do not misinterpret the findings.

In a recent CNN article, Shelby Lin Erdman reports on a new development from MIT researchers who “discovered an energy source that you can see only through a microscope,”

The original research published in the journal Nature Materials describes a highly novel way of channeling energy generated by a chemical reaction through carbon nanotubes. This discovery has revolutionary implications for reducing the size of batteries and other devices, and as such should be applauded.

But, Erdman could have offered more information to clarify for readers the technology’s limitations, its long-term prospects and its potential toxicity. Simply including comments from one or more experts not involved in the development of the technology would have gone a long way to putting this story into context.

Firstly, the discovery is not an “energy source;” instead it is a new way of transmitting energy generated by a chemical reaction. Secondly, the realistic applications of this technology are still a long way from becoming a reality.

A third point concerns toxicity. The article’s senior author asserts that “batteries made from this new thermopower technology would be completely nontoxic.” While reassuring, this is not accurate. Recent research studies have repeatedly shown that carbon nanotubes – the nanomaterials used to make these new devices – are toxic to cells,  rats and mice.

The article further states that when burnt the devices would produce only carbon since these new “batteries” would be made of carbon-containing materials. While this is theoretically true, the process of making carbon nanotubes usually requires heavy metals – such as cobalt, nickel or iron – which become incorporated into the nanomaterials. Incinerating the tubes could produce toxic metal oxides, although little is understood about how nanomaterials behave under those circumstances.

In sum, while this article highlights an important step forward in the development of small energetic materials, by misinterpreting the science, the journalist gives readers an overly optimistic understanding of this discovery’s implications. This could be easily avoided by including opinions from other experts knowledgeable about the subject.