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New Nanoparticles Shed Light on Cell Behavior

 

Christopher Smallwood by Christopher Smallwood  June 29th, 2009
37.873798, -122.254475

(left) A cell imaged with an optical microscope. (right) The same cell imaged by allowing the cell to absorb UCNPs and then irradiating it with infrared light. Each nanocrystal is one thousand times smaller than the width of a human hair. Image courtesy of PNAS."Like a silent black mist, nanoparticles began to come into the room underneath the west door…Inside the room, the particles appeared to spin and swirl aimlessly, but I knew they would self-organize in a few moments."

Thus proceeds Michael Crichton's 2002 thriller, Prey, as the protagonists face off against a malicious swarm of flesh-hungry nano-robots that are the offspring of a most unholy marriage of biological, computer science, and engineering research efforts.

Real science capabilities lag somewhat behind, but researchers succeeded recently in demonstrating an exciting new class of nanoparticle with potential applications in biological imaging. The new crystals, more formally known as lanthanide-doped upconverting nanoparticles (UCNPs), were fabricated and studied under the direction of principle investigators Bruce Cohen and James Schuck at Lawrence Berkeley National Laboratory's Molecular Foundry, and results were published on June 18th in a paper by Shiwei Wu and others in the Proceedings of the National Academy of Sciences (PNAS).

Happily, while Crichton's nanoparticles coordinated an attack on a your vital organs, these particles behave more like benign light bulbs. After allowing a living cell to absorb the UCNPs, researchers shine infrared laser light on the cell, and the nanocrystals within light up like a Christmas tree in red or green arrays of dots. These, in turn, can easily be spotted using an optical microscope and used to map out particle distributions within a cell, yielding information impossible to obtain by other methods.

The method, known as single-molecule imaging, has been demonstrated using other nanoparticle types, but UCNPs are unique because of their uncommon brightness and stability, and because they are powered by infrared light. This is both good for the studied cells, because infrared light is less damaging than visible or X-ray frequencies, and good for the people measuring them, because it can probe more deeply into tissue than other types of light. In fact, one prospect for future research is the imaging of entire animals.

Reflecting on the research effort's long-term goals, Cohen commented that cross-disciplinary sharing of ideas is crucial. "In general, we'd like to bring nanoscience to the larger scientific community, especially biology, where few researchers have had much exposure to it," he said. "Our goal is to make interesting and useful new materials that will let them do all sorts of experiments that would otherwise be impossible."

Tweeting for Energy Efficiency

 

Jim Gunshinan by Jim Gunshinan  June 26th, 2009
37.8686, -122.267

Are you using Twitter or other social media as a way to promote progressive causes like energy efficiency? What do you think about mandatory home energy audits or line drying clothes versus machine drying? Source image: Tina KellerSomebody close to me recently turned 50. Okay, it was me who just turned 50. My how things have changed since 1959! My first experience with computers was as a freshman lining up to hand over my punch cards to the computer operator to be fed into a computer that filled a room. Up until recently I got my news of the world through newspapers and television. For most of my life I stayed in touch with distant family and friends through letters and phone calls. When my brother was in Vietnam during the war we had to call him through short wave radio to tell him that his Corvette got smashed. (He didn't care. He was relieved that we were all okay.)

Now I get my information mostly off the Internet and through Twitter, the social media service that is in the news because of its use by the opposition parties in Iran. Twitter is like snail mail cubed. You send messages from your computer or smart phone that immediately show up on the computers or phones of all your "followers." You get followers generally by following others. It's kind of an unwritten rule that if someone is following you should return the favor. So far I am following about 30 people or groups and have 11 followers. But I just started.

I am following Energy Circle, a new Internet resource that is using social media to report news about home energy efficiency on Twitter. A recent "tweet" connected me to an article by Peggy in Toronto who thinks that mandatory home inspections should be replaced with mandatory energy audits upon the time of sale of a home. Advanced Energy's Research Director Melissa Malkin-Weber, tweeted "Energy saving smugness nixes scratchiness of air dried sheets. But don't ask my kids about how those stiff cloth diapers felt."

I agree with Peggie and Melissa. But what do you think about mandatory home energy audits or line drying clothes versus machine drying? Are you using social media as a way to promote progressive causes like energy efficiency? You can respond below, and your response needn't be limited, like "tweets" are, to 140 characters. Or sign up for a Twitter account and join the conversation at KQED Science!

Reporter's Notes: Where's my Hydrogen Highway

 

David Gorn by David Gorn  June 12th, 2009
37.68203, -121.7683

Hydrogen is not exactly a fuel. That is, we don't burn it to make energy. It's used more as a medium for storing and transporting energy.

The science of hydrogen fuel cell systems is based on a simple concept. When you combine hydrogen with oxygen, energy is released. You get electricity. What makes it such a clean technology is that the byproducts of that chemical reaction are just heat and water.  So when a fuel cell takes hydrogen from a fuel tank and combines it with oxygen in the air, it produces electricity and emits only a wisp of heated water vapor from the tailpipe.

Hydrogen is combustible (remember the Hindenburg?), and needs to be handled carefully. However, there are easy ways to demonstrate electrolysis, which breaks water apart into oxygen and hydrogen, and the opposite process of joining those chemicals. In fact, you could make a type of fuel cell in your kitchen, with a popsicle stick, battery clips, Scotch tape and a few other household products. You do need one item that can't be found in your kitchen: platinum wire or platinum-coated nickel wire.

Hydrogen is the most abundant element in the universe. And hydrogen fuel cell conversion is a squeaky clean technology. But the production of hydrogen for use in fuel cells — that can produce a lot of carbon dioxide. In fact, most hydrogen is currently made by stripping, or re-forming, natural gas. That's one of the ongoing criticisms of fuel-cell technology, that it generates greenhouse gas emissions just to get the hydrogen in the first place.

Fuel cells also can store energy generated by solar-powered electrolysis, as well as similar energy generated by wind and hydropower. That's the kind of hydrogen generation that advocates hope to eventually use in fuel cells. But being able to store energy also makes it extremely attractive to harnessing wind, solar and hydropower.

For example, California could generate a lot of wind energy at night, but since electricity has to be used right away, that nighttime, offpeak energy is less valuable. But if it could be stored in a fuel cell through the electrolysis process, that would make it much more lucrative.

Listen to the Where's my Hydrogen Highway? radio report online, and watch our Web Extra Slideshow.


Playing the Oldest Recordings

 

Rachel Zurer by Rachel Zurer  June 12th, 2009
37.7626411, -122.409253

A phonautograph, which made the first sound recordings (playback made possible thanks to Lawrence Berkeley National Lab

Last summer, QUEST told you about how scientists at Lawrence Berkeley National Lab have developed a technology to playback old audio recordings using visual scans. Along with bringing to life the wax cylinders we featured in our TV story, the Berkeley technology helped the world hear, for the first time ever, the oldest known sound recordings ever made. Now the historians who unearthed those recordings have discovered that they've been playing them all wrong.

The recordings were made by a phonautograph, invented by a Frenchman named Léon Scott more than 20 years before Edison came up with the phonograph. The technology worked by scratching sound waves onto sheets of paper covered with lampblack. Last year, historians used the Berkeley Lab's "visual stylus" to replay an 1860 recording of what they thought was a young girl singing the French song "Au Claire De La Lune". Since then, they've realized that they were actually playing the recording at double speed. Instead, it's likely the inventor himself doing the singing. You can hear both version at FirstSounds.org, or listen to an interview with the historians from NPR. It turns out learning to play old sounds isn't the only challenge — we have to know how to play them right!

Watch "How Edison Got His Groove Back" to learn more about how LBL's innovations are helping restore old sound:


QUEST on KQED Public Media.

The National Ignition Facility: An Energetic Defense

 

Christopher Smallwood by Christopher Smallwood  June 1st, 2009
37.679754, -121.698912

This past Friday, a few thousand folks attended Lawrence Livermore National Laboratory to see dignitaries including California Governor Arnold Schwarzenegger and U.S. Senator Dianne Feinstein dedicated the world's newest and most powerful laser, the National Ignition Facility (NIF).

Governor Schwarzenegger, clad in a pink tie– an odd sartorial choice for dedicating this giant hulk of a building housing 500 trillion watt laser housed within– nevertheless succeeded in channeling at least some of his Hollywood days. When they originally visited the facility last November, "we were so excited that we said, 'We'll be back.'"

The project's goal is to focus 192 laser beams onto a BB-sized capsule of hydrogen fuel in order to heat it to the point of ignition, that is, to achieve a nuclear fusion reaction where more energy comes out of the capsule than is put in. Fusion is the common process for creating energy in the Sun, and has been demonstrated on Earth both in the apocalyptic specter of thermonuclear weapons and in the more hope-inspiring form of plasma reactors such as those at the Joint European Torus (JET) in Britain. However, ignition has yet to be demonstrated, as JET requires a constant influx of energy greater than anything it is capable of producing. If all goes well within the next several months, ignition could be achieved at NIF as early as 2010.

For all of these exciting aspirations and promise of new technology, the press' reaction to NIF throughout the twelve years of its construction has been often lukewarm, and at worst scornful. Some of this has been deserved, and it is certainly true that the facility's $3.5 billion dollar construction cost is a hard price tag to swallow.

However, NIF is a worthy scientific cause and might well turn out to be an excellent investment. To put things a little bit into perspective, other large science projects are similarly expensive. The Large Hadron Collider (LHC) at CERN and the Hubble Space Telescope have both been estimated at about $6 billion. Dianne Feinstein argued in the past (and reminded the audience at Friday's dedication) that Enron needlessly cost $9 billion during the California Energy Crisis. Put another way, with $9 billion you could (a) experience rolling blackouts while Enron power traders cheer for wildfires ravaging your countryside, or (b) assemble the world's most powerful laser and use it to bring the nation to the brink of being able to replicate, in a controlled manner, the sorts of reactions that power the Sun. Twice.

The physics promise of the NIF, meanwhile, is truly fascinating on all three fronts of NIF's stated goals: energy production, basic research, and national security.

Fission reactors, which extract atomic energy from the splitting of large atoms such as uranium, have been a viable source of energy since 1954. However, the waste they produce remains radioactive for thousands of years. Potential fusion plants, on the other hand, would operate by an altogether different mechanism: the merging of much smaller hydrogen atoms. Radioactive byproducts are still generated, but the timescale for their radioactivity is shorter, on the order of 10 to 20 years.

A significant line of inquiry has already been pursued toward commercially viable nuclear fusion at JET and its planned successor, ITER. Such experiments employ powerful magnetic fields to maintain hydrogen plasma in a confined space and heat it to the point of fusion as it soars around inside a doughnut-shaped ring.

NIF serves as a valuable compliment to these magnetic confinement experiments. Instead of forcing a fusion reaction to perpetuate using costly magnetic fields, the NIF laser will attempt to blast its fuel with so much energy in such a short time period that the fuel will have no time to expand before it undergoes fusion. "If it works, developments at NIF would entirely reshape the dialogue on nuclear fusion energy," said Brian MacGowan, a NIF Program Director.

Even the most optimistic estimates place the viability of these types of energy sources 20 years into the future. NIF itself will never be able to function as a power generator even if all experiments performed at the facility proceed exactly as planned. The raw potential for such power extraction is nevertheless tantalizing.

Additionally, there is basic research potential for NIF beyond fusion power. Stars are typically easy to observe from a distance but inevitably too far away and too inhospitable to explore up close. A miniaturized version of the reaction as created in the NIF target bay could provide an interesting model system. There is no way to tell, but it could be that hand in hand with this ability comes a better understanding of some of the deepest outstanding questions in physics as well, such as the nature of dark energy and dark matter.

NIF also offers a unique way for the U.S. to test the effects of nuclear weapons without violating the Comprehensive Nuclear Test Ban Treaty. NNSA Administrator Tom D'Agostino noted at the dedication that, particularly as the United States' nuclear arsenal ages, this will provide the U.S. with invaluable data.

We may emerge from this economic crisis a poorer, humbler country. Still, I hope that we are not yet so humble that we have lost the ability to dream big, and not yet so poor that we can no longer actively pursue at least a few of those dreams.

Reporter's Notes: Do-It-Yourself Mini-Satellites

 

Lauren Sommer by Lauren Sommer  May 15th, 2009
37.42444, -122.16714

Cal Poly's CP-4 mini-satellite in orbit. Credit: The Aerospace
Corporation.

It's a classic engineering story - a garage inventor spends years working in isolation, only to produce something that gets the attention of the world. Ok, the CubeSat story may not be quite as romantic, but it does have a lot of the same ingredients.

Professors at Stanford University and Cal Poly created CubeSats - 10 by 10 by 10 centimeter mini-satellites - as enginneering projects to give their students hands-on experience. Compared to standard satellite missions, which can run hundreds of millions of dollars and take years to complete, CubeSat missions are mean to be done cheaply and quickly.

CubeSat is also a standard - a basic blueprint that any university program can use. CubeSats are actually known as "FedEx satellites," since universities can mail them to Cal Poly to arrange a ride into space. They've created launching devices called P-Pods (a box that fits the CubeSats perfectly) so they can piggyback on larger rocket launches. Once the main cargo is deployed, the P-Pod releases the CubeSats into orbit. Depending how high they are, CubeSats can orbit for more than a decade before they burn up in the atmosphere.

What started at universities has spread - NASA, Boeing and other aerospace companies all have mini-satellite programs. Despite the small size, CubeSats are actually able to do valuable research. They can space test new technology, submitting it to all the rigors of space travel like solar radiation and launch stress. Recreating those conditions on the ground can be very expensive.

CubeSats can also gather scientific data. On Tuesday, NASA will be launching Pharmasat, which they hope will be their second nano-satellite in orbit. It will carry yeast samples, and once in orbit will hit them with an anti-fungal to see if their resistance is increased in space. NASA has previously observed that some bacteria are more resistant to antibiotics in space, something that could be dangerous for future human space travel.

You can tune in on Tuesday evening for the Pharmasat launch. Three other CubeSats from Cal Poly and other organizations will also be getting a lift into space.


Listen to the Do-It-Yourself Mini-Satellites radio report online, and see our Web Extra: Mini-Satellites Slideshow.


LEED or Get Out of the Way

 

Jim Gunshinan by Jim Gunshinan  May 15th, 2009
37.8686, -122.267

This is a LEED-certified building on Columbus Circle
in New York City. Anything wrong with this picture?
The Leadership in Energy and Environmental Design (LEED) program has been around for many years, and has became a well-known "brand" among builders, developers and much of the general public nationwide. The program was developed and is administered by the U.S. Green Building Council (USGBC). There are LEED certifications (certified, silver, gold, and platinum) for commercial and residential buildings, building retrofits, and the USGBC is developing a LEED certification for neighborhoods. The focus of LEED is to mark buildings (and now neighborhoods) that are sustainable, healthy, and energy efficient. The program has become so popular and well known that many cities now require that new municipal buildings be built to LEED standards.

But there is some question as to whether LEED buildings actually save energy. Henry Gifford, an engineer and mechanical system designer in New York City, "…the best data available shows that on average, they (LEED-certified buildings) use more energy than comparable buildings." His view is controversial, but I have seen the data he used and have studied his analysis and it seems reasonable to me, though I am not a statistician and have done a limited amount of number crunching in my short career as an engineer before becoming a writer.

I have heard the arguments from the other side and haven't been convinced. Even from a common sense perspective, it seams unrealistic that LEED buildings are built to save energy. I've seen too many LEED certified buildings with a large percentage of windows as exterior walls–that is like trying to build an energy efficient building without walls. Also, LEED certification does not require performance testing of buildings. A building can achieve points for energy efficiency from modeling alone. In my role as editor of Home Energy Magazine, I have wanted to publish in-depth articles about LEED-certified homes, but I have been unable to find a LEED-certified building owner or designer who is willing to publish a full year of performance data, post-occupancy.

The LEED program has made green building a common term and a sought after designation among architects, builders, and developers across the nation. LEED buildings may use more environmentally friendly materials and be healthier for their occupants. But it is not yet clear to me that they save energy compared to business as usual. If we want to achieve energy independence, combat the worst effects of global warming, and grow a green economy, we can't afford to build–and celebrate–buildings built as usual.

Those Intermittent Renewables - Part 2

 

Rachel Zurer by Rachel Zurer  May 13th, 2009
37.7626411, -122.409253

To store power for the grid, we'll need some bigger batteries.
Credit: Heather Kennedy

"We believe energy storage is the next big thing," says Craig Horne, CEO of EnerVault, a Sunnyvale startup. His company is developing a battery that could help solve a renewable energy problem (check out our previous post): how to keep electricity flowing when we need it, even as more of it comes from sources we can't control. Horne was a panelist at a UC Berkeley-Stanford sponsored CleanTech Conference about energy storage held last week at Berkeley's Lawrence Hall of Science.

Proponents of energy storage think it has a key role to play in the future energy grid. A network of storage systems could act as a kind of shock-absorber, balancing the spikes and troughs of production that can come from solar and wind power. For example, if we had a way to store the power generated by wind turbines during a storm, we could release it later when demand gets high, making the power supply more constant.

We all use batteries daily – in cell phones or electronics – so it’s clear we already have the technology to store electricity and use it later. Unfortunately, that technology doesn't scale up very easily; batteries that can store enough energy to help smooth the grid are expensive, though company's like Horne's are hoping to change that. (For more on the challenges facing battery technology in particular, check out the QUEST TV story, Waiting for the Electric Car).

Batteries are just one strategy on the table, however; there are lots of ideas for how to store power at a large scale. One that's already in use in California is pumped-hydroelectric storage, which uses excess power to pump water from a low reservoir to a higher one. To get the energy back, you let the water flow the other direction, turning turbines to generate electricity as it drops in elevation. Compressed air energy storage (CAES), features a similarly clever use of the laws of physics, using excess power to compress air, which then releases energy as it expands later.

Another scheme includes using the sun – but in this case, it’s used to heat molten salt, which retains heat for a long time and can generate power even after the sun stops shining. Even electric cars could become a storage device if they become widespread, using their relatively small, distributed batteries to help feed power back to the grid at peak times.

So why aren't these technologies already being used all over the place?

"There are three obstacles to storage: Cost, cost, and cost," jokes Haresh Kamath, a Senior Project Manager at the Electric Power Research Institute, and also a panelist at the conference. Energy storage on the scale we'd need with the technology we have today is prohibitively expensive.

That may start to change, however. The stimulus package includes about $600 million for energy storage demonstrations, a 30% investment tax credit that applies to energy storage projects, and $2 billion for battery development and manufacturing. Venture capital firms are looking to invest. And there's a bill currently before the California legislature that encourages utilities to invest in and build storage.

Those injections of money and attention may be enough to get more energy storage projects off the ground – or at least get people thinking about them. Hopefully the conversations will keep going, and going, and going…

For more on the conference and specific storage technologies, check out this FAQ over at Earth2Tech.


Reporter's Notes: Let's Weatherize!

 

Amy Standen by Amy Standen  April 24th, 2009
38.63861, -121.46020


Since people seem to nod off a bit when I say I'm working on a story about energy efficiency, I've had to re-tool my pitch. "It's a story about how installing solar panels or a wind turbine is the last thing you should do to green your house," I say, perhaps a little over-dramatically.

I have nothing against solar panels, but they do seem to illustrate our collective love of gadgetry. Why else would we leap (or at least dream of leaping) to spend $5,000-$10,000 on solar panels when many of us could make a significant dent in our utility bills with a trip to Home Depot? Small things, like weather-stripping your doors, or making sure you have a well-insulated attic, can make a big difference in how much heat or AC your house consumes.

If you qualify as low-income (in this case, that's less than $44,000 for a family of four) you can get help with this project. If you live in California, you'll find your local participating agency here (or by calling 1-866-675-6623). Elsewhere, begin by contacting your state agency, found here. The Weatherization Assistance Program has received a 10-fold budget increase under the American Recovery and Reinvestment Act, so now's a great time to apply.

WAP won't replace your TV, but you might consider doing so yourself. Televisions tend to be the third biggest electricity user in the house (after heating/AC and refrigerators). But they don't have to be. All the new features — plasma screens, HD, widescreen — can be (and are, in some models) achieved using less electricity. The California Energy Commission is proposing new TV standards that would cut electricity use by a third.

James Sweeney, who heads the Stanford University Precourt Energy Efficiency Center, calculates that collectively – with current, affordable technologies, and without sacrificing our quality of life – Americans could cut our energy use by 30 percent.

Here's the kicker: To produce that same amount of electricity, we'd have to increase solar and wind by 60-fold. That means, for every solar panel and wind turbine in the country, we'd have to build 59 new ones, plus all the power lines and roads they'd entail. Or, to consider another non-fossil fuels alternative, that's four new nuclear power plants for every existing one.

Listen to the Let's Weatherize! radio report online, and watch our Weatherization Slideshow.


Have the Energy Munchies? Curb your "Snackwell Effect"

 

Jim Gunshinan by Jim Gunshinan  April 21st, 2009
37.8686, -122.267

Recent articles in USA Today and California's Flex Your Power e-Newswire discussed the phenomenon known in energy efficiency circles as "take back" or the "Snackwell Effect" (see "Consumers Can Sabotage Energy-Saving Efforts," and "The Snackwell Effect: Consumers Sabotage Energy-Saving Efforts").

Stanley Jevons first described the take back effect in 1865, so this is nothing new. Jevons observed that new efficient steam engines decreased coal consumption, which led to a drop in coal prices. But the lower prices meant that more people could afford to use coal, and so coal consumption increased.

The "Snackwell Effect" takes it's meaning from the habit of people on diets who eat lots of low-cal snacks that add up to many times the calories of a regular snack. The example given in both articles mentioned above is a West Virginia couple that bought an energy efficient washing machine to replace their old inefficient one. Their energy bills were no different after the conversion. Turns out they were doing more loads of laundry, even washing one piece of clothing in one load, because they were lulled into complacency by their energy efficient purchase.

I asked Jim McMahon, the head of the Energy Analysis Program at Lawrence Berkeley National Laboratory (LBNL), about the Snackwell Effect and appliance energy use. I recently heard him speak about the great efficiency gains made between the first energy crisis brought on by the Arab oil embargo in 1973, and today. Those gains are significant; refrigerators today use about half the energy on average than they did in the 1970s. "This effect [Snackwell Effect] has been studied for a long time, [it was] formerly called the rebound or take back effect," he says. One 2001 study concluded that for every gain in energy efficiency, about 10% is taken back by an increase in energy use. Greater air conditioner efficiency, for example, may mean that people lower their thermostats, since they expect their energy bills to be lower, and this eats into the efficiency savings. "I think that there are a number of energy-using devices where consumers do not exhibit the Snackwell effect, such as refrigerators or televisions. In those cases, in my view, the usage behaviors are unrelated to the cost of energy, at least for most households in the United States," says McMahon. He does admit that more study is needed in this area. A 10% take back effect is significant, but certainly not a barrier to serious energy efficiency improvements.

Karen Ehrhardt-Martinez, a sociologist, studies human behavior and energy use for the American Council for an Energy Efficient Economy (ACEEE). "The relationship between energy efficiency and energy consumption is not as straightforward as it may initially appear and as some people like to portray it."

The trends show that: 1) residential energy consumption increased by roughly 57% between 1970 and 2005; and 2) residential energy consumption per capita increased by only 7%".

According to Ehrhardt-Martinez, a bigger problem than the 10% of energy lost due to the take-back effect-or the Snackwell Effect-is the proliferation of energy using, albeit more efficient, devices in American homes; lifestyle choices, such as the dramatic increase in the size of homes while families got smaller; population increase; and the "invisible" energy, such as standby power or phantom loads, that is hidden from consumers. "However," says Erhardt-Martinez "if we were able to combine efficiency improvements with better lifestyle choices (i.e. smaller, more energy efficient houses), smart purchasing behaviors, and improved information mechanisms that allowed consumer to actively manage their energy consumption, then we could have a much more dramatic impact on both household level consumption as well as state and national level consumption."

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