Physics | Insights by Danielle Fong

January 22, 2012

Green Dreams: Life in the Year of the Rabbit

I’ve lived a lifetime this year. It sometimes feels as if so much is happening that one can feel however one chooses. Yet, sometimes, life gives you so much to feel happy about you can’t help but be overwhelmed with a feeling of gratitude.

We’ve launched our new website, and finally revealed the technology that we’ve developed and we think is going to change the world — regenerative air energy storage!

LightSail set out to prove that the science of our regenerative air energy storage concept works, and we have answered that challenge with a triumphant yes!

LightSail's Industrial Scale Prototype

We built an industrial scale machine by modifying a commercial natural gas compressor. We changed the cylinder head, added nozzles, replaced valves to allow reversibility, coated the surfaces to prevent corrosion, and threw our minds and hearts at the problem of showing that our approach could dramatically increase the efficiency of compressed air energy storage. Without water spray, and without burning natural gas, previous attempts at storing energy in compressed air topped out at less than 50% thermal efficiency — ok for a backup system, but not enough to change the world. This year, we aimed at greater than 80% thermal efficiency, at a high RPM (and therefore power), to show that unlike what people had assumed, high efficiency does not mean sacrificing performance.

We met or exceeded all our technical targets — demonstrating record breaking performance at the same time as record breaking thermodynamic efficiency — conclusively demonstrating our water spray heat transfer idea behind our regenerative air energy storage concept is effective at industrial scale.

Afterglow: the day I presented to Bill Gates

We presented to Bill Gates, a limited partner in the fund that invested in us. He was super excited by the potential of our project — that if we hit our targets it would change the world.

We spoke before hundreds of policy makers and energy executives, and helped instate groundbreaking legislation supporting energy storage in California.

Governor Jerry Brown

We have settled on our ultimate product architecture and design — a huge accomplishment. We’ve got a long way to go, but our models predict our experimental results within 5% RME accuracy, so we have some real confidence that it will hit all our hoped for technical specs.

We truly defined our market and value proposition. We’re aiming to make renewables plus energy storage a better and less expensive way to provide high value peak power than what the conventional sources — natural gas peakers, diesel gensets, and extra transmission wires — can muster.

The Trillion Dollar Formula

This is an utterly enormous market; at least a trillion dollars in size over the next couple decades.

IEA Estimates of Energy Infrastructure Investment Over 2008-2030. More than 30% could be economically addressed by renewables + energy storage

We’ve found that we’re uniquely positioned to reach that target, providing the lowest levelized cost of dispatchable electricity of any source, way ahead of our competitors.

But most of all, we’re excited about changing the world. Not only does energy storage make a renewables based grid possible, it also makes it economical. That’s the key to changing the world!

We’ve been working hard to uncover the greatest, most urgent opportunities for energy storage worldwide, and the opportunities we’ve turned up are simply massive. Energy storage is just what’s needed in places as diverse as Hawaii, Texas, Ireland, California, Paris, Denmark, Iceland, Nova Scotia, New York City, Australia, Chile, Dubai, India, and Subsaharan Africa. The scale and diversity of opportunities were astonishing. The most amazing thing? The willingness of governments to put their feet forward and most towards a future that’s right. We have been cynical; we believed that only once we had a full product, a long history, and economic parity under the most conservative of assumptions would governments move. We were proven wrong. Governments are leading the world into a clean future of energy. It’s utilities that are pushing back!

Steve the Redeemer

Take Iceland — a country of stark beauty. More than 80% of the country’s electricity is exported in the form of aluminum — the processing of which is one of the most energy intensive for any widely used material in the modern world. This single industry represents 40% of the Icelandic economy.

The Hellisheidi Geothermal Plant in Iceland's Golden Circle

Essentially 100% of their grid electricity comes from their amazing geothermal and hydroelectricity resources, and an enormous amount of their heating comes from geothermal cogeneration. Iceland is a land of abundant green energy.

Gullfoss -- the golden falls.

There’s a catch, though. Transmitting power across the sparse, weatherbeaten land is an expensive, unreliable proposition, where remote locations risk being knock completely off-grid with each storm. This is worse than it seems — if power is cut to aluminum smelters, the aluminum freezes, severely damaging the equipment. To backup the geothermal and hydro plants, then, industries have had to co-locate with diesel gensets — hardly a solution in light of the self reliance and environmental commitment of the Icelanders. We intend to replace these gensets completely. But we can do a lot more.

Low-temperature geothermal heat is available nearly everywhere in Iceland, and we can harness it. By expanding air at a higher temperature (and therefore pressure and volume) than when it was compressed, we get more mechanical energy out than we needed to compress it. This allows us to convert heat energy into mechanical energy, and from there, electricity. So instead of sitting idly like backup diesel gensets, our machines can be producing clean, geothermal energy, constantly; leaving the compressed air available for bursts of power when the grid fails.

So, we met with Iceland’s Minister of Energy — a former thermodynamics professor at Lund University, who bemoaned parliament’s inability to understand the concept of exergy.

We have therefore ‘rebranded’ our efforts. From now on, we have an initiative in ‘energy quality management.’ This they understand.

He understood the implications of an economical energy storage and geothermal electric generator immediately, and urged us to consider a project in Iceland. This is exactly the sort of progressive movement that governments are making and utilities resist. But we will overcome their skepticism! Stay tuned.

Catching My First Wave - A Good Omen

Of course, it wasn’t all business. If your mission call upon you to travel, it is your duty to truly experience the place. So I took the time harness some of nature’s forces myself. After I visited the grid operator and wind farms of Hawaii, I learned to surf!

We have continued to hire and improve our utterly world class team. We’re almost 30 people now, but I can tell you I have never before seen or even imagined such a diversity interests or depth of talent in a group. I work with the most amazing people I’ve met in my life! It is amazing to see how rapidly people are growing, but even more amazing to see how much more we can accomplish as a team. There are things that we literally couldn’t do on our own given all the time in the world — we have such a diverse set of skills in the company that we can make amazing things happen.

It was our first Burning Man. Our minds were blown. It is more than a festival, more than an amazing city. It is the most spiritually profound, unashamedly sensual, and maniacally creative place I’ve ever been.

Whiteout

Offering to the Sun

Deep Playa

We travelled as the chefs of the Airship Victoria last year; an airship project that eventually intends to hoist a Tesla-coil based lightning musical instrument. The camp, directly on esplanade, next to the flaming lotus girls, the sonic cannon, the flamethrower organ, and a 24 hour bar, was a surreal experience.

The Airship Victoria

It felt like… the future! It turns out, in the future, there are lots of lights, people float around on bikes, and jellyfish hover and flow.

Wonderful. But the main thing about the future is that people can’t help but be caught in the moment.

Stargate

Our camp featured tesla-coil concerts, and there, was, admittedly, high drama before the balloons were successfully fully deployed. Despite some initial setbacks, eventually the camp lifted their payload high into the air. In a city confined to a flat lakebed, the balloons added a third dimension to the playascape.

It’s impossible to describe the sense of flow one achieves in such a dizzying storm of self expression. We danced in drum circles in the nude, rode art cars and floated glowing jelly-fish, windsurfed and found inner peace. But what was most dazzling of all was the temple.

The Temple of Transition

A strikingly elegant wooden structure, built in just 10 weeks by inspired volunteers, the temple was a deeply spiritual place of reckoning. The visitors, pilgrims of every creed, came and prayed, and made offerings for their loved ones, those who that had left them, those who they had left behind. Poems, and pictures, incense and chants, old clothes or talismans, and cherished items of every description, laid respectfully to rest, ultimately fated to return to the atmosphere aflame.

Steve was so overcome that he bent down on one knee and made an offering to his mother, a brilliant opera singer, who left the world when far too young.

I miss you so much mom. You would have loved this place. I will love you forever.

As the temple’s towers, lean and graceful, slowly surrendered to the flames, glowing sparks rose deep from the inferno, and like wisps were carried up towards the heavens. The temple of transition, once a place of cool respite, now glowed brighter than the noonday sun. The crowd gasped as a shower of blue leapt out from the flames. Someone, days before, hid fireworks that launched streams of blue from the middle of the swirling firestorm, but in that splendid moment, it was impossible not to see those glowing blue apparitions, lifted high into the glowing sky, as souls, let finally free.

Meditation, Release, a Moment of Inner Peace

Upon our return, it seemed as if the whole of LightSail met us with faces silently asking us to bring them next year! We will.

This year, we’re starting a camp — tentatively named “Cleantech”. A solar powered shower and water recovery/purification system of our own design. It will be beautiful and efficient and environmentally friendly. Our kind of project!

LightSail's Firehouse Lab

At the end of the year, having wrapped up our work at our firehouse lab, having shown all we can with our current industrial scale prototype, we moved into our new facility — the former Scharfenberger chocolate factory, in which we will design, test , and manufacture our first product line. It is an amazing space. We will do outstanding work there, and we will be happy and proud.

As the move in completed, the holidays arrived, giving us the occasion to throw a lab-warming party for our friends and family. It was absolutely amazing. I felt as if the party unfolded as a microcosm of the entire project. It began with a simple idea: “let’s have a holiday party,” which lead to the conclusion “we clearly must have it at our new space,” and from that point, it took on a life of its own, spearheaded by people of admirable competence and outstanding creativity.

We were blown away by it all. The founders had no idea! Everywhere you looked there was perfectly executed brilliance.

Enter the space, we’re greeted with placards describing what all of the work is, what each of the rooms are, how each of the items work. There were demonstrations of our tank technology, our electronics and controls, our machineshop and quality assurance, our water spray lab, and even our original prototype (built in Ed’s garage using scrap parts and ebay!) We had no idea it would be there, and were blown away to see it!

Humble Beginnings: The Original LightSail Prototype, hydraulic, quirky, built of scrap, sweat, and parts ordered off ebay.

The original machine used a hydraulic approach — slower, with less power per unit mass or cost, and with higher inefficiencies, but we conclusively proved we could control the temperature of the air during operation, and control the valves to let only an amount of air in that would expand down to 1 atmosphere — yielding the very highest efficiencies. It was a cheap, quick way to show that some of our main ideas worked, and that we could build something. We sure have come a long way from that!

Travis O’Guin and his band played an incredible set of dixieland Jazz of some of the past century’s greatest compositions (ever wonder how “hit me baby one more time” is in dixieland jazz? Amazing.) Ed broke out into dance with a series of dancers, and the LightSail toddlers couldn’t resist the beat!

Machinemaster Todd Bowers breaking it down for Professor Robert Dibble and wife Helen

The machineshop was running — demonstrations included a CNC lathe disco ball, a hula dancer shaking it to an earthquake powered by the CNC mill, and just-in-time manufacturing of LightSail Branded Bottle Openers!

Dave Sprinkle spent years in the racing industry, but it's cupcakes that bring this smile to his face...

But what really stole the party were the cupcake cars, brought in by the brilliant Keith Johnson and his merry friends Lisa Pongrace and Greg Solberg. Our partygoers insist they’re even more fun to drive than a Tesla.

It was an unbelievable way to ring-in the new year. This is going to be a great one. That everyone injected such creativity and excellence in such a gathering just shows how much people care about their work and their team and this company and how high a standard they have for themselves. It seems as if everything at LightSail is like that — our people perform at a higher level than us founders can even think to ask of them, or indeed, even to imagine.

Energy Standout of the Year, Forbes 30 Under 30. Photograph by Harry Benson

To top it all off, we received coverage from none other than Forbes Magazine. I am honored to be highlighted as the standout in the field of energy in the Forbes 30 under 30 ranking! My extended family is finally less suspicious of my dropout ways. What a relief! I had a wonderful time at home with my brothers and little cousins and found to my amazement that my family had founded four businesses between us since we last visited. I guess it’s in the genes.

Christmas in Nova Scotia

This year looks to be even better. It feels like we’re reaching escape velocity.

I am honored to have been elected a mentor for the Thiel 20 under 20 Fellowship. These kids aren’t waiting to change the world, they’re just going out and doing it — I am so excited to be working with them!

I have been tapped to judge the Nova Scotia Cleantech Open, remarkable not only for being in my home province, but also for its amazing quality, rigor, and prize money ($100k free money with $200k of seed investment available.) I’m joining Matthew Nordan, of Venrock and Lux Research, whose work and judgement I have always admired greatly. His “The State of Cleantech VC is already a classic in the field.

We’re working full-speed on our product and technology, and are rallying allies across the planet to realize a wonderful number of as yet unannounced projects and partnerships.

Last year was an amazing year, but I have a feeling this one will be even better.

I am so happy to be alive at this moment in history. Great things are afoot. The winds are changing.

13 Comments

November 15, 2008

Tick Tock

The clock stuck twelve. It’s October 30th. In a heartbeat I emerged an adult in the eyes of American law. In an alternate universe, I danced the night into a hazy sunrise. But I left celebration to Haight St. patrons, their addled revelry spilling muffled through the crack in my window. Tonight, we work.

Dawn, a night and two weeks later. It was ready; the design for the both the engine and the drivetrain, encoded in a scattered handful of drawings and documents, one wiki, two heads, and a thousand lines of physical simulation code. The first test: powering a scooter through a staccato ride amid frenzied Manhattan traffic, calculating, by the hundredth second, the will of the engine, and the vehicle’s reply. We’d follow a path devised to track emissions from humming, throbbing combustion engines, byproducts of fuel burnt in tiny explosions sparked every second by the thousands.

But nothing save cool air would our machine exhale. Compressed air, ‘a thermomechanical battery’ of sorts, is cheap, long lasting, and quick to recharge (one need only open a valve, and if impatient, run a pump, the tank will fill in seconds.) What’s more, it’s efficient. A batteries charge begins life in mechanical form, in a spinning turbine if charged off the grid, or in the inertia of a vehicle, during regenerative braking. This is then converted into AC electrical current, which is converted into DC current, which, finally, is converted into mechanical energy, losing power at each step. To power the engine this whole process runs in reverse! But compressing or expanding air keeps mechanical energy mechanical (so long as temperature is kept reasonably constant.) In powering vehicles it is superior to the most advanced battery systems known. That is, in every parameter but one.

Historically, the low energy density of compressed air had crippled any attempt to venture further than a couple dozen miles; physics, it seemed, demanded tanks of excessive proportions to travel longer. At 300 bar (‘scuba pressure’), compressed air could release only half a percent as much energy as the same volume of gasoline burnt. We understood, however; it was an efficiency war. We knew that conventional vehicles were incredibly wasteful. There were many battles left to fight.

The Laws of Thermodynamics¹

“You can’t win.”
“You can’t break even.”
“You can’t give up.”

We hunted losses relentlessly. We were repaid with a series of compounding improvements, each building upon another, reversing the conventional patterns of efficiency losses endured by vehicles for more than a century. Finally, in a brilliant and unusually compact layout by Steve Crane, we found room to replace the paltry 1.3 gallon gas tank with one ten times its size. Nights yielded to our toil, and, slowly but surely our enemy routed.

“We’ve cracked the code,” we exclaimed. “The city is ours to conquer.” On the highway, whatever benefit earned by our scooter’s light weight, low rolling resistance and ultra-efficient regenerative braking would be dominated by air resistance.² But air resistance falls quickly with speed, and in the stop-start motion of the city our combined inventions would give our scooter an efficiency historically unmatched.

I keyed in the last few drivecycle parameters, drew a shallow breath, cocked my head, and pressed the enter key. The simulation lasted only a moment, but in that time, my little scooter ran more than one hundred and twenty miles, the equivalent of dozen rides between Wall Street and the Bronx on a single tank. “We’re in business,” I said. With that, and for all of a New York Minute, the questions, worries and restlessness retreated from our hearts. We huffed. “What’s next?”

[1]: To paraphrase C. P. Snow. Hat tip to Jonathan Smith.

[2]: Scooters are not particularly aerodynamic vehicles. Ordinary scooters have a drag coefficient of nearly 0.9, and a frontal area of 0.6 meters squared. We hope to achieve a drag coefficient of 0.6, similar to faired motorcycles ridden upright, but due to the rider’s position this will be difficult: some have described the aerodynamics of a scooter as like a “brick attached to a parachute.”

9 Comments

June 8, 2008

Cosmology in Ten Minutes

Recently, unusual features of the cosmic microwave background, a ‘snapshot’ of the early universe, have raised issues with our understanding of the Big Bang. A Caltech team has shown how we might fix our theories. They suggest that there might have been an asymmetry in the energy that once powered the big bang. If this is correct, anomalies in the CMB may be traces of structure from a time before our explosive beginnings.

True to form, when a discussion appeared on Hacker News I rushed to comment, and this article erupted from that attempt. The current scientific understanding of our cosmic origins is a mystery to the public at large, but it was only after I noticed the bewilderment of my fellow hackers that I realized how poor a job we scientists have done in conveying the motivation behind our discoveries.

This article represents an attempt to replace that sense of bewilderment with that of wonder. I want more than to explain what cosmologists believe. I want give people a deep sense of why we believe it, of how we’ve come to our current understanding, and of why we care.

Look close, and it seems the universe is lopsided.

The cosmic microwave background (CMB) is like a snapshot of the early universe. It was once all hot plasma, gas so hot that the atoms inside it were broken up. Because it was hot, it emitted light. Because it was dense, it was opaque: the light emitted couldn’t just pass through, instead it had to bounce around. But once cool enough, the universe became transparent: all the light could now travel freely. It was as if the photographic shutter of the universe was lifted.

The light from this moment became the cosmic microwave background radiation. Because the universe seemed to have cooled at almost exactly the same time everywhere, the CMB is, unlike almost everything else in astronomy¹, a picture of the entire universe at almost exactly the same moment in time. It is the best picture we have of the structure of the early universe.

The universe appears to have expanded evenly since then. We know it’s expanding now. Light is like a wave. Since the speed of light is constant, an illuminated object moving towards us has its wave crests squish together, turning bluer, and an object moving away from us has the distance between crests expand, turning more red. This is called a red shift. Since he knew the colors of certain celestial objects, Edwin Hubble was able to observe that the further something is from us, the more red-shifted its light, and therefore the faster it is speeding away.

Since we know that the early universe was hot, dense and small, and we know now that it’s cooler, sparse, big, and expanding, we can reasonably deduce that, long ago, there was a Big Bang. The universe exploded.

Strikingly, the CMB is almost the same everywhere you look. There are minor fluctuations, but even they seem to have the same distribution everywhere. The CMB, our best picture of the early universe, is extraordinarily smooth. It is one of the smoothest things ever observed in nature. This might not seem like a mystery. You might imagine that anything expanding, hot and dense would look roughly the same in all directions. It needn’t. Nebulae are formed by exploding stars, and they aren’t particularly smooth. In fact, in nature, it would seem, more often than not, that explosions are messy.

In 1981, Alan Guth suggested what might be called a ‘recipe for a universe’: inflation theory. Until then, nobody had come up with any good ideas for why the universe was so smooth and even. It is as if God² had pressed the entire universe with a cosmic clothes iron.

Guth said, suppose you started with pretty much any initial universe. Suppose you also had an extremely strong, extremely smooth field of energy. If this field started dumping energy into the rest of the universe, it would also evenly expand space itself.³ The universe would undergo a period of exponential expansion — inflation — having the effect of flattening and smoothing the rest of the universe. Inflation is God’s clothing iron.

A flat, smooth universe isn’t the only thing that inflation predicted. For example, at small physical scales, quantum mechanical fluctuations persist. During inflation these fluctuations are blown up as well, and these would seed, almost entirely, the cosmological structure of the universe. We see these fluctuations in the CMB. According to inflation, they are tiny quantum fluctuations blown up to a cosmic scale. They are, quite literally, the ancestors of our galaxies.

It wasn’t just that there were fluctuations. Inflation theory predicted a very specific distribution and type⁴. When people finally had the technological capability to check, that’s just what they found. The universe appeared, at a cosmic scale, astonishingly consistent with this simple theory. Yet recently our observational capacities have improved. A CMB survey called WMAP has uncovered several surprising and unexplained features, not all of which fit well with the our previous inflation theories.

If you divided the sky in half by tracing the orbit of the earth around the sun⁵, and compared, in each half, the size of big fluctuations, those between 3 and 5 degrees wide, you would come to the conclusion that one side has fluctuations outweighing the other by an alarmingly large amount. One side of the universe is bumpier than the other. Moreover, the difference is larger than would be accounted for by randomness, at least 99 times out of 100.⁶

This asymmetry looks real. It has been checked against every known experimental error and background effect astrophysicists have been able to think of. And if it is real, our previous inflation theories, with one field of energy to inflate the early universe, won’t work. They can’t account for this anomaly.

The authors Erickcek, Kamionkowski, and Carroll don’t merely point out this problem. They posit a solution. They describe another inflation model, consistent with our new observations. They suggest the universe had not one, but many fields of universe inflating energy. There’s just one problem. At least one of these fields needs to be asymmetric.

Where could such an asymmetry come from? It is possible that we’ll never know. Cosmology offers us the hope of uncovering consistent, compelling stories of our origins. Thousands of independent observations fit neatly in cosmology’s book. But while we may discover a few lost pages from our first chapters, we may never know all reasons why our book was written in the first place.⁷

Nevertheless, the authors make an exciting point. Wherever the asymmetry in the inflation field came from, it must have existed before inflation. It must have existed before the big bang. We had once imagined that time before our explosive beginnings would forever remain a mystery. Yet hidden in the CMB are hints of times earlier still. In this wonderful piece of work, the authors carefully consider what anomalies in the CMB could mean. And in the process, they may have discovered a way to look farther into the past than ever before.

Notes:

[1] – Since light moves at a finite speed, when we see something far away, we’re seeing light emitted in the past. What we see of something a light-year away is (at least) one year old.

[2] – I mean ‘God’ here as in a figure of speech. Feel free to substitute ‘Mother Nature’, ‘Allah’, or the ‘Flying Spaghetti Monster’ while reading.

[3] – What does it mean, exactly, for energy to expand space itself? It’s roughly analogous to blowing up a balloon. We know that the gravity of the universe, just like the elastic outside walls of a balloon, pull its contents inward. In a balloon, air pressure pushes against that inward force of the walls. During cosmic inflation, the inflationary force pushes against gravity. There’s one important difference though. We don’t actually know what the inflationary force is. Air blows up our balloons, but we have few clues as to what blew up the universe.

[4] – The quantum fluctuations predicted by inflation follow a nearly-scale-invariant random Gaussian distribution. These fluctuations show up in the CMB, and for the most part follow these predictions pretty closely.

[5] – The line dividing the two halves of the sky here is called the ecliptic.

[6] – Formally, this statement is true at at least the 99% confidence level.

[7] – There are some questions forever beyond our grasp. Even if we knew from where the Big Bang had come, we could always probe further, and ask where that came from.

16 Comments