Blatant Reality

NPR has a nice article discussing how much energy the sun provides the earth when compared to how much we use each year. Basically, the amount the sun provides (86,000 terawatts/year) far outweighs the energy we use (15 terawatts/year). The only problem is that we don’t have the technology to properly harness and store all this energy. Therefore, the author argues that we should look to photosynthesis to properly store all this power.

And what is the best plant out there to do this? Algae.

Meanwhile, it turns out that there’s a great way to make oil from sunshine. It’s called photosynthesis. Plants absorb sunlight and use the energy to convert atmospheric CO2 into organic products. Indeed, that’s how our current hydrocarbon reserves were generated in the first place: with the aid of geology, the ancient products of photosynthesis were crushed and converted into oil and coal.

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Most land plants don’t make oil except in their seeds; the CO2 they fix goes largely into making shoots and roots and walls and starch, material that can be converted into ethanol but not into oil. But there’s a diverse and abundant population of photosynthetic organisms, collectively called the algae, that can be induced to make the likes of olive oil, oil that can fly jet airplanes just fine.

So, full disclosure: About two years ago I started up some experiments in my lab that related to algal biodiesel, and they worked, and I now have funding from the Department of Energy to pursue these leads. Having studied the sex life of a particular green soil alga, Chlamydomonas reinhardtii, all my research life, during which we made lots of cool discoveries that had no planetary impact whatsoever, it’s a trip to be asking interesting questions of Chlamy that are potentially also relevant.

When you deprive Chlamy of nitrogen, it bloats up with triacylglycerides (TAGs) until it looks like a fat-guy cartoon. (The image accompanying this blog shows this, where the red is chlorophyll fluorescence and the yellow comes from a dye that fluoresces yellow when it’s embedded in TAGs.])Same goes for marine diatoms: they all but burst with TAGs when deprived of silicon. Chemists can take these TAGs and readily convert them into transportation fuels. Better yet, the fat-extracted algae can be dried down and fed to chickens.

The algal biodiesel field is in its infancy. The solar industry is booming by comparison. There are daunting problems to be solved: how to grow enough cells and maximally elicit their TAG potential; how to protect them from the predators that make their way into cultivation ponds; how to harvest the TAGs. But there are also very smart engineers and start-up companies thinking hard about how to implement this potential source of fuel.

A new catalyst has been developed that separates the Oxygen from a water molecule. The hope is that with this cheap catalysts, researchers will be able to develop a way for the sun to power the necessary reaction, thus creating a new, sustainable source of energy.

Daniel Nocera, a professor of chemistry at MIT, has developed a catalyst that can generate oxygen from a glass of water by splitting water molecules. The reaction frees hydrogen ions to make hydrogen gas. The catalyst, which is easy and cheap to make, could be used to generate vast amounts of hydrogen using sunlight to power the reactions. The hydrogen can then be burned or run through a fuel cell to generate electricity whenever it’s needed, including when the sun isn’t shining.

 

Solar power is ultimately limited by the fact that the solar cells only produce their peak output for a few hours each day. The proposed solution of using sunlight to split water, storing solar energy in the form of hydrogen, hasn’t been practical because the reaction required too much energy, and suitable catalysts were too expensive or used extremely rare materials. Nocera’s catalyst clears the way for cheap and abundant water-splitting technologies.

 

Nocera’s advance represents a key discovery in an effort by many chemical research groups to create artificial photosynthesis–mimicking how plants use sunlight to split water to make usable energy. “This discovery is simply groundbreaking,” says Karsten Meyer, a professor of chemistry at Friedrich Alexander University, in Germany. “Nocera has probably put a lot of researchers out of business.” For solar power, Meyer says, “this is probably the most important single discovery of the century.”

However, this still doesn’t solve all the problems with using hydrogen as a fuel. Another catalyst needs to be developed to create hydrogen ions that is cheaper than the current platinum ones used.

Nocera created the catalyst as part of a research program whose goal was to develop artificial photosynthesis that works more efficiently than photosynthesis and produces useful fuels, such as hydrogen. Nocera has solved one of the most challenging parts of artificial photosynthesis: generating oxygen from water. Two more steps remain. One is replacing the expensive platinum catalyst for making hydrogen from hydrogen ions with a catalyst based on a cheap and abundant metal, as Nocera has done with the oxygen catalyst.

 

Finding a cheaper catalyst for making hydrogen shouldn’t be too difficult, says John Turner, a principal investigator at the National Renewable Energy Laboratory, in Golden, CO. Indeed, Nocera says that he has promising new materials that might work, and other researchers also have likely candidates. The second remaining step in artificial photosynthesis is developing a material that absorbs sunlight, generating the electrons needed to power the water-splitting catalysts. That will allow Nocera’s catalyst to run directly on sunlight; right now, it runs on electricity taken from an outlet.

While this is definitely a promising step in the right direction, I wouldn’t hold my breath until they will discover the necessary catalyst.

Yep, it seems like something from the book I, Robot but scientists are actually saying that it might be feasible to collect solar energy in space and beam it down to earth.

Picture this: a 6-mile-wide solar-power satellite orbiting 22,000 miles in space. Photo-sensitive panels on the satellite collect light from the sun and turn it into microwave radiation that an antenna beams down to a ground station, where it’s converted into enough electricity to power a large city.

 

Sound like science fiction? Last year, a government study group issued a report that said space-based solar power not only was technically feasible but also offered a potentially clean, renewable source of energy that could significantly reduce our dependence on fossil fuels.

Sounds pretty good, right? Well I still have my doubts. With a $1 trillion price tag, it seems a little steep. Plus, the thing about space is that if something breaks down, its really hard to maintenance it. Personally, I don’t think that we have exhausted our options here on earth so elaborate solar collection satellites in space seems a little extreme.

I’ve never really been a big fan of solar power for at least wide spread use because of its inherent limitations (sunny Arizona might do quite well with solar power but rainy Washington probably wouldn’t work out so well). However, leave it to scientists (actually MIT engineers) to find a way to get me even interested into the future of solar power.

It seems that they have found a way to use ordinary windows coated with certain dyes to collect solar energy.

MIT engineers have turned plain glass into a virtual goldmine of solar energy with the help of a sophisticated, yet affordable, concentrator developed by them.

 

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The technology, using dye-coated glass to collect and channel photons otherwise lost from a solar panel’s surface, could enable an office building to draw energy from its tinted windows as well as its roof.

 

The engineers coated glass panels with layers of two or more light-capturing dyes. The dyes absorbed incoming light and then re-emitted the energy into the glass, which served as a conduit to channel the light to solar cells along the panels’ edges.

 

The dyes can vary from bright colours to chemicals mostly transparent to visible light. Because the glass panel edges are so thin, far less semiconductor material is needed to collect light energy and convert it into power.

 

Because the materials are affordable, relatively easy to scale up beyond a lab setting, and easy to retrofit to existing panels, the researchers believe the technology could find its way to the marketplace within three years.

See, you might not believe me but I had thought about how cool it would be to actually have buildings that use their windows as solar energy collectors. I mean, for skyscrapers, this will give them tons more surface area to collect energy that just having traditional rooftop solar panels.

Now what really gets me excited about this particular technology is the whole “materials are affordable” part. As you probably know, scientists are constantly making some fairly cool stuff but then fail at making it even remotely economical to implement in the real world.

Once again I just want to state I am all for alternative energy sources as long as they are affordable and people are not coerced (by the government or otherwise) to use them. If the technology can survive and prosper on an open market, then by all means. I just hate all the subsidies that the government gives some of these schemes (tax breaks/incentives are a whole different thing).

I can’t wait to see just where this technology will go because it just might give the solar industry to boost it needs to really become one of the front runners in alternative energy.