Powered by the Sun: The “Energy Duck”

Magnificent CME Erupts on the Sun - August 31Part of the challenge of paving the way towards a future where solar power is able to meet our energy needs is finding ways to integrate it into our daily lives. Basically, until such time as efficiency limits, storage and intermittency problems are truly overcome, one of the best ways to do this is to place photovoltaic arrays where the demand is highest and to get creative with how they collect it.

For example, a group of British artists have conceptualized a giant solar harvesting floating duck as part of the 2014 Land Art Generator Initiative Copenhagen design competition. Dubbed “Energy Duck”, the giant structure has been designed not only to generate clean electricity for the local residents of Copenhagen, but to also provide a unique visitor center. In short, it comes renewable energy with a cautionary message about the effects of Climate Change.

energyduckInspired by the arctic eider duck, Energy Duck not only hopes to offer a unique renewable energy source, but also highlight the impact that climate change has had on the local population and breeding habitats of the eider duck in recent years. As its creators – Hareth Pochee, Adam Khan, Louis Leger and Patrick Fryer – explained:

Energy Duck is an entertaining iconic sculpture, a renewable energy generator, a habitable tourist destination and a celebration of local wildlife.

Covered in photovoltaic panels, the Energy Duck is designed to harvest solar energy from every inch of its exterior shell. Solar cells mounted around the base are also positioned to take advantage of the sun’s rays being reflected off the water’s surface. Additionally, the facility features hydro turbines which use water pressure to provide stored energy to the grid after sunset and during the evening.

https://i0.wp.com/images.gizmag.com/gallery_lrg/energyduck-2.jpgAll of this helps the Energy Duck overcome the all-important issue of intermittency. By being able to generate energy around the clock, the Duck is not dependent on the sun shining in order to continue operating and providing power. As the team explained:

When stored energy needs to be delivered, the duck is flooded through one or more hydro turbines to generate electricity, which is transmitted to the national grid by the same route as the PV panel-generated electricity. Solar energy is later used to pump the water back out of the duck, and buoyancy brings it to the surface. The floating height of the duck indicates the relative cost of electricity as a function of city-wide use: as demand peaks the duck sinks.

Inside the giant Energy Duck, visitors can get a unique look into the working mechanics of the hydro turbines, watching as the water levels rise and fall. Sunlight also filters through small spaces between the exterior solar panels, providing a kaleidoscope-like view of Copenhagen. However, another interesting feature about the Energy Duck is its environmental message.

energyduck-5So while people are visiting the interior and taking note of the impressive technology, they will also be getting a lesson in why it is important. And really, the inherent message of the concept is really very appropriate. A clean, renewable, alternative energy source designed to look like, and inspired by, one of the many creatures that is endangered because of humanity’s dependence on unclean fuels.

Now if we could just design a land-roving solar farm in the shape of a polar bear!

Sources: gizmag.com, inhabitat.com

Powered by the Sun: Boosting Solar Efficiency

solar1Improving the efficiency of solar power – which is currently the most promising alternative energy source – is central to ensuring that it an becomes economically viable replacement to fossil fuels, coal, and other “dirty” sources. And while many solutions have emerged in recent years that have led to improvements in solar panel efficiency, many developments are also aimed at the other end of things – i.e. improving the storage capacity of solar batteries.

In the former case, a group of scientists working with the University of Utah believe they’ve discovered a method of substantially boosting solar cell efficiencies. By adding a polychromat layer that separates and sorts incoming light, redirecting it to strike particular layers in a multijunction cell, they hope to create a commercial cell that can absorb more wavelengths of light, and therefor generate more energy for volume than conventional cells.

EMSpectrumTraditionally, solar cell technology has struggled to overcome a significant efficiency problem. The type of substrate used dictates how much energy can be absorbed from sunlight — but each type of substrate (silicon, gallium arsenide, indium gallium arsenide, and many others) corresponds to capturing a particular wavelength of energy. Cheap solar cells built on inexpensive silicon have a maximum theoretical efficiency of 34% and a practical (real-world) efficiency of around 22%.

At the other end of things, there are multijunction cells. These use multiple layers of substrates to capture a larger section of the sun’s spectrum and can reach up to 87% efficiency in theory – but are currently limited to 43% in practice. What’s more, these types of multijunction cells are extremely expensive and have intricate wiring and precise structures, all of which leads to increased production and installation costs.

SolarCellResearchIn contrast, the cell created by the University of Utah used two layers — indium gallium phosphide (for visible light) and gallium arsenide for infrared light. According to the research team, when their polychromat was added, the power efficiency increased by 16 percent. The team also ran simulations of a polychromat layer with up to eight different absorbtion layers and claim that it could potentially yield an efficiency increase of up to 50%.

However, there were some footnotes to their report which temper the good news. For one, the potential gain has not been tested yet, so any major increases in solar efficiency remain theoretical at this time. Second, the report states that the reported gain was a percentage of a percentage, meaning that if the original cell efficiency was 30%, then a gain of 16% percent means that the new efficiency is 34.8%. That’s still a huge gain for a polychromat layer that is easily produced, but not as impressive as it originally sounded.

PolyChromat-640x353However, given that the biggest barrier to multi-junction solar cell technology is manufacturing complexity and associated cost, anything that boosts cell efficiency on the front end without requiring any major changes to the manufacturing process is going to help with the long-term commercialization of the technology. Advances like this could help make technologies cost effective for personal deployment and allow them to scale in a similar fashion to cheaper devices.

In the latter case, where energy storage is concerned, a California-based startup called Enervault recently unveiled battery technology that could increase the amount of renewable energy utilities can use. The technology is based on inexpensive materials that researchers had largely given up on because batteries made from them didn’t last long enough to be practical. But the company says it has figured out how to make the batteries last for decades.

SONY DSCThe technology is being demonstrated in a large battery at a facility in the California desert near Modeso, 0ne that stores one megawatt-hour of electricity, enough to run 10,000 100-watt light bulbs for an hour. The company has been testing a similar, though much smaller, version of the technology for about two years with good results. It has also raised $30 million in funding, including a $5 million grant from the U.S. Department of Energy.

The technology is a type of flow battery, so called because the energy storage materials are in liquid form. They are stored in big tanks until they’re needed and then pumped through a relatively small device (called a stack) where they interact to generate electricity. Building bigger tanks is relatively cheap, so the more energy storage is needed, the better the economics become. That means the batteries are best suited for storing hours’ or days’ worth of electricity, and not delivering quick bursts.

solarpanelsThis is especially good news for solar and wind companies, which have remained plagued by problems of energy storage despite improvements in both yield and efficiency. Enervault says that when the batteries are produced commercially at even larger sizes, they will cost just a fifth as much as vanadium redox flow batteries, which have been demonstrated at large scales and are probably the type of flow battery closest to market right now.

And the idea is not reserved to just startups. Researchers at Harvard recently made a flow battery that could prove cheaper than Enervault’s, but the prototype is small and could take many years to turn into a marketable version. An MIT spinoff, Sun Catalytix, is also developing an advanced flow battery, but its prototype is also small. And other types of inexpensive, long-duration batteries are being developed, using materials such as molten metals.

Sumitomo-redox-flow-battery-YokohamaOne significant drawback to the technology is that it’s less than 70 percent efficient, which falls short of the 90 percent efficiency of many batteries. The company says the economics still work out, but such a wasteful battery might not be ideal for large-scale renewable energy. More solar panels would have to be installed to make up for the waste. What’s more, the market for batteries designed to store hours of electricity is still uncertain.

A combination of advanced weather forecasts, responsive fossil-fuel power plants, better transmission networks, and smart controls for wind and solar power could delay the need for them. California is requiring its utilities to invest in energy storage but hasn’t specified what kind, and it’s not clear what types of batteries will prove most valuable in the near term, slow-charging ones like Enervault’s or those that deliver quicker bursts of power to make up for short-term variations in energy supply.

Tesla Motors, one company developing the latter type, hopes to make them affordable by producing them at a huge factory. And developments and new materials are being considered all time (i.e. graphene) that are improving both the efficiency and storage capacity of batteries. And with solar panels and wind becoming increasingly cost-effective, the likelihood of storage methods catching up is all but inevitable.

Sources: extremetech.com, technologyreview.com

 

Powered by the Sun: Solar City and Silevo

solar2Elon Musk is at it again, this time with clean, renewable energy. Just yesterday, he announced that Solar City (the solar installation company that he chairs) plans to acquire a startup called Silevo. This producer of high-efficiency panels was acquired for $200 million (plus up to $150 million more if the company meets certain goals), and Musk now plans to build a huge factory to produce their panels as part of a strategy that will make solar power “way cheaper” than power from fossil fuels.

Solar City is one of the country’s largest and fastest-growing solar installers, largely as a result of its innovative business model. Conceived by Musk as another cost-reducing gesture, the company allows homeowners and businesses to avoid any up-front cost. If its plans pan out, it will also become a major manufacturer of solar panels, with by far the largest factory in the U.S.

https://i2.wp.com/images.fastcompany.com/upload/620-most-innovative-companies-solar-city.jpgThe acquisition makes sense given that Silevo’s technology has the potential to reduce the cost of installing solar panels, Solar City’s main business. But the decision to build a huge factory in the U.S. seems daring – especially given the recent failures of other U.S.-based solar manufacturers in the face of competition from Asia. Ultimately, however, Solar City may have little choice, since it needs to find ways to reduce costs to keep growing.

Silevo produces solar panels that are roughly 15 to 20 percent more efficient than conventional ones thanks to the use of thin films of silicon – which increase efficiency by helping electrons flow more freely out of the material – and copper rather than silver electrodes to save costs. Higher efficiency can yield big savings on installation costs, which often exceed the cost of the panels themselves, because fewer panels are needed to generate a given amount of power.

http://gigaom2.files.wordpress.com/2011/10/silevo-single-buss-bar-cell.jpgSilevo isn’t the only company to produce high-efficiency solar cells. A version made by Panasonic is just as efficient, and SunPower makes ones that are significantly more so. But Silevo claims that its panels could be made as cheaply as conventional ones if they could scale their production capacity up from their current 32 megawatts to the factory Musk has planned, which is expected to produce 1,000 megawatts or more.

The factory plan mirrors an idea Musk introduced at one of his other companies, Tesla Motors, which is building a huge “gigafactory” that he says will reduce the cost of batteries for electric cars. The proposed plant would have more lithium-ion battery capacity than all current factories combined. And combined with Musk’s release of the patents, which he hopes will speed development, it is clear Musk has both eyes on making clean technology cheaper.

Not sure, but I think it’s fair to say Musk just became my hero! Not only is he all about the development of grand ideas, he is clearly willing to sacrifice profit and a monopolistic grasp on technologies in order to see them come to fruition.

Source: technologyreview.com

Powered by the Sun: Solar Buildings and Wind Towers

Magnificent CME Erupts on the Sun - August 31In our ongoing drive to find ways to meet energy demands in a clean and sustainable way, solar power is the clearly the top contender. While inroads have certainly been made in terms of fusion technology, the clean, abundant, and renewable power that can be derived from our sun seems to hold the most promise. In addition to the ever-decreasing costs associated with the manufacture and installation of solar cells, new applications that are appearing all the time that allow for greater usage and efficiency.

Consider the following example that comes from Seoul, Korea, where Hanwa – the largest solar company in the world – has chosen to retrofit its aging headquarters with a solar facade that will provide both for the buildings needs and cut down on energy costs. Having been built in the 1980’s, the Hanwa building is part of a global problem. High-rise buildings suck up around 16% of the world’s energy, and most were built to specifications that do not include sustainability or self-sufficiency.

solar_skyscraper3Even though the most recently-built skyscrapers are helping change things by employing renewable energy and sustainable methods – like the Pertamina Energy Tower in Jakarta –  that still leaves tens of thousands of inefficient giant buildings on the ground. And rather than tear them down and erect new buildings in their place, which would be very wasteful and inefficient, it is possible to convert these buildings into something cleaner and less reliant on other external sources of electricity.

Basically, the plan calls for plastering the 29-story building with three-hundred new solar panels. These will be placed on the sunniest spots to harvest energy, and other strategically placed panels will automatically adjust to help keep the interior cool but bright with natural light. New high-performance windows will save more energy. In total, though the final details are still in progress, the retrofit may save well over a million kilowatt-hours of electricity each year.

solar_skyscraper2In theory, say designers from Amsterdam-based UNStudio, this type of facade could be added onto any skyscraper. As the researcher explains:

It would be the principles that could be applied of course and not the design, as every building has its own context, program, size, view corridors, orientation etc. which would affect the design parameters differently. Each building would be unique and would require a tailored approach.

Retrofitting old skyscrapers is an important way for cities to fight climate change, say engineers from ARUP, which worked with UNStudio on optimizing the design. And it’s usually a better solution than building something brand new. Accroding to Vincent Cheng, who led the project from ARUP’s Hong Kong studio, retrofitting is a better option for old skycrapers, both in “terms of reducing embodied carbon emission and waste elimination.”

solar_downdraft_towerAt the other end of things, there are the ongoing efforts to expand solar power production to the point that it will supersede coal, hydro, and nuclear in terms of electrical generation. And that’s the idea behind the Solar Downdraft Tower, a proposed installation some 686 meters (2,250 feet) in height with 120 huge turbines and enough pumping capacity to keep more than 2.5 billion gallons of water circulating. In terms of output, it would generate the equivalent of wind turbines spread over 100,000 acres, or as big as the Hoover Dam.

The process is quite simple: water is sprayed at the top, causing hot air to become heavy and fall through the tower. By the time it reaches the bottom, it’s reaching speeds of up to 80 km (50 miles) per hour, which is ideal for running the turbines. The immediate advantage over standard solar and wind energy is the plant runs continuously, day and night. This addresses the issue of intermittency, which remains a problem with solar and wind generation.

solar_downdraft_tower2Basically, solar and wind farms cannot provide if the weather is not cooperating, or if the solar cells become covered in dust or sand. But as long as the local environment remains warm enough – a near certainty in the deserts of Arizona – the tower will continue to produce power. Best of all, the plant itself runs under its own generated energy – with approx. 11% of the output being used to power the pumps – and aboutt three-quarters of the water is collected at the bottom.

According to Ron Pickett, CEO of Solar Wind Energy Tower (the Maryland company behind the design):

This is totally clean energy that actually makes money. It makes energy at a cost comparable to if you were using natural gas to power a plant.

The simplicity of the technology is also a major selling point. For more than a century, people have been working on variants of solar wind towers. In the 1980s, engineers in Spain built a 195 meter (640-foot) test tower that pushed air upwards through turbines and generated power for seven years until it fell over in a storm. The tougher issue is the enormous expense, which is an inevitable result of building something so big. According to Picket, the Arizona project is likely to cost as much as $1.5 billion to build.

solar_downdraft_tower1However, Solar Wind Energy recently jumped two hurdles to getting the tower realized. First, it won a development rights agreement from San Luis, a city on the Mexico border, that included a deal with the local utility to purchase power, and the rights to the 2.5 billion gallons of water necessary to the project. It also reached an agreeing with National Standard Finance, an infrastructure fund, for preliminary funding that will begin to pay for generating equipment and related costs.

Solar Wind Energy also has plans to see similar towers build in Chile, India, and the Middle East, places that are also well suited to turn warm air temperatures into electrical power. And they are hardly alone in looking for ways to turn solar power into abundant electricity in ways that are technically very simple. As the 2010s roll on, we can expect to see more and more examples of this as renewables make their way into the mainstream.

In the meantime, check out this video from Solar Wind Energy that details how their Tower concept works:


Sources:
fastcoexist.com, (2)

The Future is Fusion: Surpassing the “Break-Even” Point

JET_fusionreactorFor decades, scientists have dreamed of the day when cold fusion – and the clean, infinite energy it promises – could be made possible. And in recent years, many positive strides have been taken in that direction, to the point where scientists are now able to “break-even”. What this means is, it has become the norm for research labs to be able to produce as much energy from a cold fusion reaction as it takes in triggering that reaction in the first place.

And now, the world’s best fusion reactor – located in Oxfordshire, Engand – will become the first fusion power experiment to attempt to surpass it. This experiment, known as the Joint European Torus (JET), has held the world record for fusion reactor efficiency since 1997. If JET can reach break-even point, there’s a very good chance that the massive International Thermonuclear Experimental Reactor (ITER) currently being built in France will be able to finally achieve the dream of self-sustaining fusion. 

NASA_fusionchamber

Originally built in 1983, the JET project was conceived by the European Community (precursor to the EU) as a means of making fusion power a reality. After being unveiled the following year at a former Royal Navy airfield near Culham in Oxfordshire, with Queen Elizabeth II herself in attendance, experiments began on triggering a cold fusion reaction. By 1997, 16 megawatts of fusion power were produced from an input power of 24 megawatts, for a fusion energy gain factor of around 0.7.

Since that time, no one else has come close. The National Ignition Facility – the only other “large gain” fusion experiment on the planet, located in California – recently claimed to have broken the break-even point with their  laser-powered process. However, these claims are apparently mitigated by the fact that their 500 terrawat process (that’s 500 trillion watts!) is highly inefficient when compared to what is being used in Europe.

NIF Livermore July 2008Currently, there are two competing approaches for the artificial creation of nuclear fusion. Whereas the NIF uses “inertial confinement” – which uses lasers to create enough heat and pressure to trigger nuclear fusion – the JET project uses a process known as “magnetic confinement”. This process, where deuterium and tritium fuel are fused within a doughnut-shaped device (a tokamak) and the resulting thermal and electrical energy that is released provides power.

Of the two, magnetic confinement is usually considered a better prospect for the limitless production of clean energy, and this is the process the 500-megawatt ITER fusion reactor once its up and running. And while JET itself is a fairly low-power experiment (38 megawatts), it’s still very exciting because it’s essentially a small-scale prototype of the larger ITER. For instance, JET has been upgraded in the past few years with features that are part of the ITER design.

fusion_energyThese include a wall of solid beryllium that can withstand being bombarded by ultra-high-energy neutrons and temperatures in excess of 200 million degrees. This is a key part of achieving a sustained fusion reaction, which requires that a wall is in place to bounce all the hot neutrons created by the fusion of deuterium and tritium back into the reaction, rather than letting them escape. With this new wall in place, the scientists at JET are preparing to pump up the reaction and pray that more energy is created.

Here’s hoping they are successful! As it stands, there are still many who feel that fusion is a pipe-dream, and not just because previous experiments that claimed success turned out to be hoaxes. With so much riding on humanity’s ability to find a clean, alternative energy source, the prospects of a breakthrough do seem like the stuff of dreams. I sincerely hope those dreams become a reality within my own lifetime…

Sources: extremetech.com, (2)

Powered by Wind: World’s Tiniest Windmills

tiny_windmillWind turbines are one of the fastest growing industries thanks to their ability to provide clean, renewable energy. And while most designs are trending towards larger and larger sizes and power yields, some are looking in the opposite direction. By equipping everyday objects with tiny windmills, we just might find our way towards a future where batteries are unnecessary.

Professor J.C. Chiao and his postdoc Dr. Smitha Rao of the University of Texas at Arlington are two individuals who are making this idea into a reality. Their new MEMS-based nickel alloy windmill is so small that 10 could be mounted on a single grain of rice. Aimed at very-small-scale energy harvesting applications, these windmills could recharge batteries for smartphones, and directly power ultra-low-power electronic devices.

tiny_windmill1These micro-windmills – called horizontal axis wind turbines – have a three-bladed rotor that is 1.8 mm in diameter, 100 microns thick, and are mounted on a tower about 2 mm tall mount. Despite their tiny size, the micro-windmills can endure strong winds, owing to being constructed of a tough nickel alloy rather than silicon, which is typical of most microelectromechanical systems (MEMS), and a smart aerodynamic design.

According to Dr. Rao, the problem with most MEMS designs is that they are too fragile, owing to silicon and silicon oxide’s brittle nature. Nickel alloy, by contrast, is very durable, and the clever design and size of the windmill means that several thousands of them could be applied to a single 200 mm (8 inch) silicon wafer, which in turn makes for very low cost-per-unit prices.

tiny_windmill2The windmills were crafted using origami techniques that allow two-dimensional shapes to be electroplated on a flat plane, then self-assembled into 3D moving mechanical structures. Rao and Chiao created the windmill for a Taiwanese superconductor company called WinMEMS, which developed the fabrication technique. And as Rao stats, they were interested in her work in micro-robotics:

It’s very gratifying to first be noticed by an international company and second to work on something like this where you can see immediately how it might be used. However, I think we’ve only scratched the surface on how these micro-windmills might be used.

Chiao claims that the windmills could perhaps be crafted into panels of thousands, which could then be attached to the sides of buildings to harvest wind energy for lighting, security, or wireless communication. So in addition to wind tunnels, large turbines, and piezoelectric fronds, literally every surface on a building could be turned into a micro-generator.

Powered by the wind indeed! And in the meantime, check out this video from WinMEMS, showcasing one of the micro-windmills in action:


Source: news.cnet.com, gizmag.com

The Future of Energy: Cold Fusion for US and China

NASA_coldfusionThe science behind cold fusion has been a source of constant controversy for decades. Not only has this pursuit turned up its share of phony claims, the fact that it also promises to yield clean, abundant energy on the cheap has led to no shortage of romantic endorsements and vocal detractors. But if it could be made to work, there is no doubt that our energy problems would be solved, and in a way that is not harmful to our environment.

Last February, NASA made waves by announcing that they were working towards cold fusion through low-energy nuclear reaction (LENR) technology. Then in September, the National Ignition Facility (NIF) in California announced a major milestone when they managed to produce a controlled reaction that provided more energy that was required to start it.

e-cat1But all of that seemed to pale in comparison to the announcement by Andrea Rossi’s that he managed to create a fusion power plant that was reportedly capable of generated a single megawatt of power. Known as the E-Cat 1MW Plant (short for Energy-Catalyser), Rossi announced its creation back in November, and indicated that he and his company were taking pre-orders and that they would start deliveries by 2014.

Today, the big news is that a large US investment company has acquired the rights to the cold fusion LENR technology. That investment company is Cherokee Investment Partners, and they appear to be interested in deploying the cold fusion tech commercially in both China and the US to meet both countries existing and projected energy needs.

fusion_energyRelying on the same process as other LENR technology, the E-Cat generates cold fusion by taking nickel and hydrogen and fusing them into copper – a process that has 10,000 times the energy density of gasoline, and 1,000 times the power density. Rossi says he’s found a special catalyst that makes the process work, but many scientists remain unconvinced.

Regardless of whether or it not it can deliver, it now seems that Rossi’s previously allusions to an American partner are true after all. Much like everything surrounding Rossi, he chose to be nebulous about the identity of the company that was supporting him. However, with this latest deal, Cherokee and its CEO Thomas Darden, a man who has a history of investing in clean energy, is a believer in the design.

e-cat3In addition to preparing the patents through a Limited Liability Company – known as Industrial Heat – there are also reports that Darden recently visited China to showcase the E-Cat to Chinese officials and businesspeople. China is reportedly looking at using the E-Cat to significantly reduce its carbon footprint and meet its the energy needs of its growing cities in a way that won’t generate more air pollution.

Needless to say, this deal has bolstered Rossi’s and the E-Cat’s credibility, but the technology remains unproven. Rossi says that he has a team of international scientists that are planning to do another round of tests on the E-Cat which are slated to end in March, with a peer-reviewed report to follow sometime after that. Fingers crossed, those rounds of test will provide conclusive proof.

Then, we can all get to work dreaming about a bright, clean future, and the thousands of applications such plants will have!

Source: extremetech.com