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Archive → July, 2011

Getting to 54.5 MPG

If your very next car purchase had to meet the new mileage standards announced today, you’d be buying something roughly the size of a thimble. It would certainly be smaller than the petite Ford Fiesta, which gets a comparatively gluttonous 38 miles per gallon, highway.

Or, you could do away with any MPG concerns and get a new all-electric Nissan Leaf, though the range can dip down to around 62 miles.  Forget the comfy hybrid Toyota Prius – that one only gets 50 MPG overall.

Luckily for car buyers, automakers have until 2025 to get their fleet average up to 54.5 MPG. By then, the choices will be much different than today.

Today’s New York Times story on the increase focuses on plans for hybrid and electric cars. But other technologies will have to come into play. According to Sujit Das of the Center for Transportation Analysis at Oak Ridge National Laboratory, drive train changes will not be enough to meet the new standards.

There will be more electric and hybrid cars, but overall, Das says, passenger cars will also have to be made smaller and lighter. Part of the problem is that it is too expensive to make larger trucks and SUVs high mileage, and automakers still want to sell a lot of those. So, regular cars will have to be designed for REALLY high gas mileage to make the averages work out.

Oak Ridge scientists estimate that for every 10% of weight reduction in a vehicle, the gas mileage improves by 6.5%. To make that happen, they are studying how automakers can use lightweighting materials including advanced high-strength steels, aluminum, magnesium, titanium, and composites including metal-matrix materials and glass- and carbon-fiber reinforced thermosets and thermoplastics.

Automakers have been using lighter weight materials for years, but not in a quest to increase mileage. According to a report [PDF] by the Pew Center on Global Climate Change, “Although technology to improve vehicle efficiency is available and is being used in vehicles now, vehicle manufacturers have directed much of the potential of the technology to purposes other than fuel economy, such as making vehicles larger and more powerful.”  That’s a strategy that they’ll have to re-think.

Still, carbon fiber is not the first choice for automakers. Not too long ago I priced a carbon-fiber bicycle, and decided it was way too expensive. A carbon fiber car would be like George Jetson’s flying car that folds into a suitcase. It doesn’t exist, and if it did, very few people could afford it. Though parking would be a snap. The cost problem is a real barrier, which is why Oak Ridge scientists are also studying ways to make lightweighting materials more affordable.

Meanwhile, an organization called the Diesel Technology Forum says more people are choosing “clean diesel” cars, and that the new standards will bring more diesel models for consumers. The new diesel cars perform well on the highway – the Volkswagon Jetta TDI gets 42 MPG highway. A fiberglass and aluminum version would likely get even more.

The new mileage standards will also likely force automakers to experiment with more efficient designs for combustion engines.  New approaches get more mechanical power from the same amount of gas, bypassing steps where energy is lost as heat.

A start-up called Transonic Combustion builds a system that heats and pressurizes gasoline into a supercritical state before directly injecting it into the combustion chamber. There, like in diesel engines, no spark is needed to ignite the fuel and move the piston. It is an efficiency improvement that the company says can increase mileage by 50%.

DuPont gets Solar Blues from Innovalight

What is silicon ink? Is it magical pixie dust? Innovalight, maker of silicon ink, is a venture capital-funded company in Silicon Valley that was just acquired by DuPont. The announcement came Monday and I’ve been wanting to post about it but a small problem held me back.

Innovalight's silicon ink. Credit: Innovalight

I had no idea how Innovalight’s product works. I knew what it is though – it’s ink (and it sure looks like ink) made up of silicon nanoparticles suspended in chemicals. It can be screen printed in the same assembly line used to manufacture crystalline silicon solar cells.

The reason a manufacturer would add this extra step is simple. It increases the cell’s ability to capture energy from sunlight by 1%. 

Since Monday I’ve learned a bit more – enough to burden blog readers with my still incomplete understanding. Adding a precision-printed design of this ink to crystalline silicon solar cells allows the cell to capture more energy from the blue wavelength of sunlight. This sentence is where I would describe exactly how the ink makes that happen, so let’s pretend I did that.

Solar cells are generally hampered in their efficiency by an inability to capture energy from the full spectrum of light. Like the human eye, they do best capturing visible light. But that leaves a wealth of radiation in the UV and infrared part of the spectrum un-captured. Thus the 19% upper limit on even very efficient cells.

Interestingly, even within the visible spectrum, blue light is not well captured. My colleague Mitch Jacoby tells me that blue light is energetic enough for a solar cell to absorb and create a flow of energized electrons, but that the high energy electron and the “hole” left behind re-combine before they hit the conducting grids and without creating a current. Many people in many places like NREL have been studying ways to keep them separated and have them move to the negative and positive current collectors.

That’s why the DuPont press release about the acquisition talks about Selective Emitter solar cells. In spite of the capitalization, the term seems a bit misleading to me, because absorbing is what they’re going for. Anyway, selective emitter approaches involve an adaptation to the silicon, the surface and/or the conducting grid to make those electrons from the blue light migrate efficiently.

Innovalight’s value proposition is that solar cell manufacturers can make selective emitters in their current process by adding a silicon ink screen printing step after texturing the mono crystalline silicon.

According to the press release, “Selective Emitter technology could represent 13 percent of crystalline silicon solar cell production by 2013 and up to 38 percent by 2020.”

Renewable Energy On and Off the Grid

A couple of items in today’s scan of cleantech news invite us to compare and contrast the differences in providing renewable power for large, grid-connected energy versus local, off-grid projects.

In China, where the government has a goal to get 170GW of electricity from wind power by 2020, wind power providers are trying to figure out how to cost-effectively connect – and stay connected – to the electric grid. Massachusetts-based A123 Systems, a maker of nanophosphate lithium-ion energy storage systems will supply batteries to a Chinese  manufacturer of wind turbines called Dongfang Electric Corporation. The batteries will be capable of storing 500kW. According to the A123 press release, only about 72% of China’s wind power capacity is connected to the grid.

Energy providers in rural India do not face the grid problem. In fact, winning technologies there are designed specifically for communities that do not have access to the grid. A Bloomberg article highlights two renewables  firms that  received early funding and support from tech firm Cisco Systems and venture capital firm Draper Fisher Jurvetson. Both have moved on from the blackboard stage and are now supplying systems to rural villagers.

Husk Power Systems builds small, 40kW biomass gasifier power plants that run on rice husks. The husks, a waste produce from rice processing is one of the few types of biomass that does not already have another use by villagers. Currently, rice millers use some of their supply, along with diesel, to power their operations. HPS’s plants can light up to 500 households and cost just under $40,000 to install. The company and its partner Shell, have installed 60 mini power plants in the Indian state of Behar.

Meanwhile, Cisco and Draper have also supported D.Light Design, a solar lamp maker that is leasing 120,000 lighting kits in homes in the southwest state of Karnataka. The price per family is the equivalent of $5-$8 a month. The lighting replaces light provided by kerosene.

More than half a billion people in India live off the grid or are connected to unreliable service. Right now, they depend mainly on fossil fuel-powered devices. Both China and India are increasing government spending for clean energy. Though technologies like A123 Systems, and creating a reliable and effective electric grid that can handle solar and wind energy have gotten a lot of attention, it’s important to realize the immense size of the market for technologies that serve off-grid populations. The technology – and social – needs for village-scale power are very different.

Algae and Water Energy

Could the energy cost of moving water sink the burgeoning algae industry?

C&EN recently checked in with a number of leading algae-growing firms to learn more about their current plans for profiting from the prolific green slime. Though eventually many hope to make money in the large market for biofuels, most firms say that other products like chemicals and high-protein fish food will go first.

Water World. Cellana's marine algae ponds are in Hawaii. Credit: Cellana

Building large-scale algae-growing systems is still too expensive to make fuels profitable. The key to bringing down costs is in the engineering of the infrastructure. A recent study by researchers at the University of Texas at Austin looked at the energy costs of moving water into and around algae-growing systems (Environ. Sci. Technol., 2011, 45 (13), pp 5861–5868).Researchers Cynthia Murphy and David Allen presented a startling conclusion:

Energy output in the form of algal biodiesel and the total energy content of algal biomass are compared to energy inputs required for water management. The analysis indicates that, for current technologies, energy required for water management alone is approximately seven times greater than energy output in the form of biodiesel and more than double that contained within the entire algal biomass.

Seven times greater?

Ouch. Like any model, this one began with a host of assumptions. Importantly, the model did not assume that algae farmers would be using fresh water, but did assume algae would be grown in open ponds (except for the inoculation vessels). In fact, the main problem is not the water itself, but the need to move it around from place to place.

First water from various sources (saline, fresh, reclaimed from the facility) needs to be obtained and pumped into the inoculation area and the algae pond. More water would be added to compensate for algae removed, evaporation and other “leaks” from the system. Evaporation would concentrate salts in the pond, and may require compensating amounts of fresh water for “blow down.” Cleaning after each growing season would require removing the water and replacing it.

In addition, energy would be required to remove water from the harvested algae, and then to return that reclaimed water to the system. The researchers also included in the model the embodied energy of the plastics used to contain the algae in ponds (and the lifespan of the plastics).

There is no way, of course, to compare the assumptions in the model to any particular firm’s proprietary growing system. But I did pose the question of water energy to the companies I spoke with that use open ponds.

Cellana’s CEO Martin Sabarsky said, “Water is a big issue. It’s an issue for biofuels generally. You have to deal with it on the backend too. We’ve developed and are continuing to optimize cost effective technology to handle water issues at the back end including dewatering. “

And Sapphire President Cynthia Warner commented, “It is true that to optimize the process and get costs down, you have to minimize water movement, maximize efficiency. Using sophisticated equipment is key.”

Washington Redskins Score 8,000 Solar Panels

I really can’t resist this little news item. File it under solar and, a new category for this blog- sports.

My hometown football team, the wonderous and often frustrating Washington Redskins will add 8,000 solar panels to their new-ish stadium. They will be working with energy firm NRG – that sounds redundant – to generate 2 MW of power from 3 different types of solar panels. They’ll include thin film and transluscent versions. The installation will also include 10 electric vehicle charging station for those Volt drivers who spurn the Metro.

Q&A With Solazyme

C&EN first wrote about leading algae firm Solazyme in 2009. At that time algae firms were gathering up venture capital funding and perfecting their technologies for growing the green slime. Many were targeting biofuels markets, but some firms had additional markets in mind.

Solazyme’s algae live in large fermentation tanks and eat sugars, which are transformed into algal oil – a type of vegetable oil. The company went public in late May, and raised $227 million from investors.

We checked in with Solazyme to find out more about its business model, and the types of markets it is targeting with its oils. Cameron Byers, senior vice president & general manager of fuels and chemicals gave us a closer look.

C&EN: I first spoke with Solazyme back in early 2009 – it seems like forever ago in algae time. Even then, the firm was targeting specialty chemicals, food, and cosmetics in addition to biofuel.  How did that diverse product strategy affect your ability to attract investors and business partners pre-IPO?

 Byers: Producing a diverse range of products is not just important, it is what our technology platform was designed to do in-line with our business model. The markets served by conventional oils – petroleum, plants and animal fats – represented an opportunity of over $3.1 trillion in 2010, an attractive potential market for investors. Solazyme’s custom oils can address each of these markets, providing both an environmentally and economically sustainable solution.  As an example, Solazyme recently announced a joint development agreement with The Dow Chemical Company to develop of a new class of algal oils tailored for optimized performance and cost in dielectric insulating fluid applications. Dielectric fluids alone represents a 500 million gallon market.

Continue reading →

… and it’s a Go for Poet’s Cellulosic Project

Yesterday Poet Energy announced that it has a conditional DOE commitment for a $105 million loan guarantee for the cellulosic ethanol plant it plans to construct in Emmetsburg, Iowa. That’s two days after I posted (below) that the company was waiting on just such an outcome. Thanks for reading my blog, Steven Chu!

Poet has been working with DOE to secure more funding for this plant, which will be co-located with an existing corn ethanol plant owed by the company. In 2007 it received a grant from DOE that was supposed to help out through the first years of design and construction. It appears that the details for that plant haven’t changed – it will produce 25 million gal a year from corn cobs, leaves, husks and some stalks.  It is scheduled for completion in 2013.

Following these projects requires a fairly strong memory. When I first wrote about the project in 2009, it was to see what had happened since the 2007 grants were issued. Poet’s project was looking like a pretty sure bet. But clearly the loan guarantee was a necessity – Poet was originally going to have the plant running this year, but was waiting on more financing.

What’s interesting is what the company has been doing in the meantime. A few numbers give you a sense of the scale of a cellulosic ethanol plant. Poet built a 22-acre holding area – called an integrated stackyard – just to store the biomass delivered by farmers.  The collection has begun – 85 farmers brought 56,000 tons of biomass to the site last year. That’s less than one-fifth of what the plant will use up in one year.

Farmers will glean about 20-25% of the waste biomass from their fields to feed the mill. Each acre would provide 1 ton of biomass. To provide the yearly allotment for the plant would require 300,000 acres of harvested corn farmland.  Poet has been working with soil scientists to study the impact of the gleanings on soil quality – and so far have found it to be “consistent with good soil management.”

It’s Stop and Go for Cellulosic Ethanol

Another Independence Day has come and gone, and it seems the U.S. is no closer to figuring out the role that cellulosic ethanol might play in promoting energy independence. At least, that is the theme expressed in a recent article in the Des Moines Register.

How now, corn cob? Credit: Poet

Dan Pillar outlines the strikes against the industry: EPA continues to down shift its expectations for cellulosic ethanol production – from a 2005 goal of 100 million gal this year to, last month, 6.5 million gal for the year. Large biorefineries  – comparable in output to corn-based ethanol - were supposed to come online this year, but have not, Pillar notes, due in large part to concerns by financiers over the future profitability of ethanol.

One example of a project on hold is Poet, a leading corn ethanol producer that is still waiting on a loan guarantee from the Department of Energy for its cellulosic operation. And politically, ethanol has been increasingly unpopular. The corn version has been blamed for increasing the cost of corn, and long-treasured subsidies are eyed for the chopping block. And the next-generation cellulose players might lose support in Congress as budgets get trimmed. One program that is at risk would help pay farmers to gather corn stover and corn cobs to feed Pilot’s plant.

Cattle farmers, already incensed at the rising cost of feed corn, are also not pleased at the possibility of losing access to harvested corn fields for grazing. Meanwhile, strategies for economically providing the “waste” agricultural materials to cellulosic ethanol plants have long been a logistical hurdle for making the next-gen ethanol plants economical.

Is cellulosic ethanol having problems financially, politically, and logistically, all at the same time? Perhaps, but though plans have slowed – and some may be in limbo – one big loan guarantee may tip the balance. Meanwhile, DuPont Danisco Cellulosic Ethanol said last week that it had acquired land for a commercial scale refinery in Nevada, Iowa, to be fed by corn stover. While it gets ready for construction, DDCE is working with Pioneer Hi-Bred, DuPont’s seed company, and Iowa State University to figure out how to work the corn stover harvesting, storage and transportation side of things.