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Tuesday, April 22, 2014

Study: Fuels from corn waste not better than gas

Monday Apr 21, 2014 | Dina Cappiello for The Associated Press


Credit: AP Photo/The University of Nebraska-Lincoln.

WASHINGTON (AP) — Biofuels made from the leftovers of harvested corn plants are worse than gasoline for global warming in the short term, a study shows, challenging the Obama administration's conclusions that they are a much cleaner oil alternative and will help combat climate change.

A $500,000 study paid for by the federal government and released Sunday in the peer-reviewed journal Nature Climate Change concludes that biofuels made with corn residue release 7 percent more greenhouse gases in the early years compared with conventional gasoline.

While biofuels are better in the long run, the study says they won't meet a standard set in a 2007 energy law to qualify as renewable fuel.

The conclusions deal a blow to what are known as cellulosic biofuels, which have received more than a billion dollars in federal support but have struggled to meet volume targets mandated by law. About half of the initial market in cellulosics is expected to be derived from corn residue.

The biofuel industry and administration officials immediately criticized the research as flawed. They said it was too simplistic in its analysis of carbon loss from soil, which can vary over a single field, and vastly overestimated how much residue farmers actually would remove once the market gets underway.

"The core analysis depicts an extreme scenario that no responsible farmer or business would ever employ because it would ruin both the land and the long-term supply of feedstock. It makes no agronomic or business sense," said Jan Koninckx, global business director for biorefineries at DuPont. Later this year the company is scheduled to finish a $200 million-plus facility in Nevada, Iowa, that will produce 30 million gallons of cellulosic ethanol using corn residue from nearby farms. An assessment paid for by DuPont said that the ethanol it will produce there could be more than 100 percent better than gasoline in terms of greenhouse gas emissions.

The research is among the first to attempt to quantify, over 12 Corn Belt states, how much carbon is lost to the atmosphere when the stalks, leaves and cobs that make up residue are removed and used to make biofuel, instead of left to naturally replenish the soil with carbon. The study found that regardless of how much corn residue is taken off the field, the process contributes to global warming. "I knew this research would be contentious," said Adam Liska, the lead author and an assistant professor of biological systems engineering at the University of Nebraska-Lincoln. "I'm amazed it has not come out more solidly until now."

The Environmental Protection Agency's own analysis, which assumed about half of corn residue would be removed from fields, found that fuel made from corn residue, also known as stover, would meet the standard in the energy law. That standard requires cellulosic biofuels to release 60 percent less carbon pollution than gasoline.

Cellulosic biofuels that don't meet that threshold could be almost impossible to make and sell. Producers wouldn't earn the $1 per gallon subsidy they need to make these expensive fuels and still make a profit. Refiners would shun the fuels because they wouldn't meet their legal obligation to use minimum amounts of next-generation biofuels.

EPA spokeswoman Liz Purchia said in a statement that the study "does not provide useful information relevant to the life cycle greenhouse gas emissions from corn stover ethanol."

But an AP investigation last year found that the EPA's analysis of corn-based ethanol failed to predict the environmental consequences accurately.

The departments of Agriculture and Energy have initiated programs with farmers to make sure residue is harvested sustainably. For instance, farmers will not receive any federal assistance for conservation programs if too much corn residue is removed.

A peer-reviewed study performed at the Energy Department's Argonne National Laboratory in 2012 found that biofuels made with corn residue were 95 percent better than gasoline in greenhouse gas emissions. That study assumed some of the residue harvested would replace power produced from coal, reducing greenhouse gas emissions, but it's unclear whether future biorefineries would do that.

Liska agrees that using some of the residue to make electricity, or planting cover crops, would reduce carbon emissions. But he did not include those in his computer simulation.

Still, corn residue is likely to be a big source early on for cellulosic biofuels, which have struggled to reach commercial scale. Last year, for the fifth time, the EPA proposed reducing the amount required by law. It set a target of 17 million gallons for 2014. The law envisioned 1.75 billion gallons being produced this year.

"The study says it will be very hard to make a biofuel that has a better greenhouse gas impact than gasoline using corn residue," which puts it in the same boat as corn-based ethanol, said David Tilman, a professor at the University of Minnesota who has done research on biofuels' emissions from the farm to the tailpipe.

Tilman said it was the best study on the issue he has seen so far.

Monday, April 14, 2014

White House Unveils Plans to Cut Methane Emissions


A worker at a hydraulic fracturing operation in Rifle, Colo. Natural gas production releases methane, which contributes to greenhouse gas pollution. Credit Brennan Linsley/Associated Press.

WASHINGTON — The Obama administration on Friday announced a strategy to start slashing emissions of methane, a powerful greenhouse gas released by landfills, cattle, and leaks from oil and natural gas production.

The methane strategy is the latest step in a series of White House actions aimed at addressing climate change without legislation from Congress. Individually, most of the steps will not be enough to drastically reduce the United States' contribution to global warming. But the Obama administration hopes that collectively they will build political support for more substantive domestic actions while signaling to other countries that the United States is serious about tackling global warming.

In a 2009 United Nations climate change accord, President Obama pledged that by 2020 the United States would lower its greenhouse gas emissions 17 percent below 2005 levels. "This methane strategy is one component, one set of actions to get there," Dan Utech, the president's special assistant for energy and climate change, said on Friday in a phone call with reporters.

Environmental advocates have long urged the Obama administration to target methane emissions. Most of the planet-warming greenhouse gas pollution in the United States comes from carbon dioxide, which is produced by burning coal, oil and natural gas. Methane accounts for just 9 percent of the nation's greenhouse gas pollution — but the gas is over 20 times more potent than carbon dioxide, so even small amounts of it can have a big impact on future global warming.

And methane emissions are projected to increase in the United States, as the nation enjoys a boom in oil and natural gas production, thanks to breakthroughs in hydraulic fracturing technology. A study published in the journal Science last month found that methane is leaking from oil and natural gas drilling sites and pipelines at rates 50 percent higher than previously thought. As he works to tackle climate change, Mr. Obama has generally supported the natural gas production boom, since natural gas, when burned for electricity, produces just half the greenhouse gas pollution of coal-fired electricity.

Environmental groups like the Sierra Club have campaigned against the boom in natural gas production, warning that it could lead to dangerous levels of methane pollution, undercutting the climate benefits of gas. The oil and gas industry has resisted pushes to regulate methane leaks from production, saying it could slow that down.

A White House official said on Friday that this spring, the Environmental Protection Agency would assess several potentially significant sources of methane and other emissions from the oil and gas sector, and that by this fall the agency "will determine how best to pursue further methane reductions from these sources." If the E.P.A. decides to develop additional regulations, it would complete them by the end of 2016 — just before Mr. Obama leaves office.

Among the steps the administration announced on Friday to address methane pollution:

  • The Interior Department will propose updated standards to reduce venting and flaring of methane from oil and gas production on public lands.
  • In April, the Interior Department's Bureau of Land Management will begin to gather public comment on the development of a program for the capture and sale of methane produced by coal mines on lands leased by the federal government.
  • This summer, the E.P.A. will propose updated standards to reduce methane emissions from new landfills and take public comment on whether to update standards for existing landfills.
  • In June, the Agriculture Department, the Energy Department and the E.P.A. will release a joint "biogas road map" aimed at accelerating adoption of methane digesters, machines that reduce methane emissions from cattle, in order to cut dairy-sector greenhouse gas emissions by 25 percent by 2020.

Advocates of climate action generally praised the plan. "Cutting methane emissions will be especially critical to climate protection as the U.S. develops its huge shale gas reserves, gaining the full greenhouse gas benefit from the switch away from coal," said Paul Bledsoe, a former White House climate change aide under President Bill Clinton, now with the German Marshall Fund.

Howard J. Feldman, director of regulatory and scientific affairs for the American Petroleum Institute, which lobbies for oil and gas companies, said he hoped the steps would not lead to new regulations on his industry. "We think regulation is not necessary at this time," he said. "People are using a lot more natural gas in the country, and that's reducing greenhouse gas."

Since cattle flatulence and manure are a significant source of methane, farmers have long been worried that a federal methane control strategy could place a burden on them. But Andrew Walmsley, director of congressional relations for the American Farm Bureau Federation, said that his group was pleased that, for now, the administration's proposals to reduce methane from cattle were voluntary.

"All indications are that it's voluntary," he said, "but we do see increased potential for scrutiny for us down the line, which would cause concern."

Source: New York Times. A version of this article appears in print on March 29, 2014, on page A12 of the New York edition with the headline: White House Unveils Plans to Cut Methane Emissions.

Monday, April 7, 2014

Green Fracking? 5 Technologies for Cleaner Shale Energy


Dusk falls at a hydraulic fracturing site in northeastern Pennsylvania. New technologies aim to reduce fracking's impact on land, water, and air.

It may seem strange to hear the words "fracking" and "environmentally friendly" in the same sentence.

After all, hydraulic fracturing, or fracking, in which high-pressure chemically treated water is used to crack rock formations and release trapped oil and gas, is a dirty term to many environmentalists. Critics decry the practice for consuming vast amounts of fresh water, creating toxic liquid waste, and adding to the atmosphere's greenhouse gas burden, mostly because of increased risk of leaks of the potent heat-trapping gas, methane. (See related quiz, "What You Don't Know About Natural Gas.")

James Hill, chief executive of the Calgary, Alberta-based energy services firm GasFrac, is one of a handful of technology pioneers determined to change that. Hill's company has introduced a new fracking method that uses no water at all. Instead, GasFrac uses a gel made from propane—a hydrocarbon that's already naturally present underground—and a combination of what it says are relatively benign chemicals, such as magnesium oxide and ferric sulfate, a chemical used in water treatment plants. Over the past few years, GasFrac has used the process 2,500 times at 700 wells in Canada and the United States.

"We're actually using hydrocarbons to produce hydrocarbons," Hill said. "It's a cycle that's more sustainable."

GasFrac is one of a growing number of companies, including giant GE and the oil services firm Halliburton, that are pioneering technological improvements to mitigate some of the environmental downsides to the process that has spurred a North American energy boom. (See Interactive, "Breaking Fuel From Rock.") Besides GasFrac's water-free method, other companies are working on ways to use recycled frack water or non-potable brine in fracking. Some are working on replacing harsh chemicals used in the process with more benign mixtures, or to cleanse water that's been used in fracking. Other innovators are looking to replace diesel-powered drilling equipment with engines or motors powered by natural gas or solar energy, and to find ways to find and seal leaks that allow methane, a potent greenhouse gas, to escape.

Such efforts have even won cautious support from some environmental activists, who've decided that it may be more realistic to mitigate the consequences of fracking than to fight its use.

"Natural gas is a potential energy bounty for the country, and development is probably inevitable," said Ben Ratner, a project manager for the nonprofit Environmental Defense Fund. (See related "Interactive: Breaking Fuel From Rock" and "The Great Shale Gas Rush.") "That's why we're investing our energy into doing everything, from science to policy to working with companies, to maximize the potential climate advantage that gas has over coal, and minimize the risk to public health and the environment. We think natural gas can be an exit ramp from coal, but we have to do it right." (See related, "U.S. Energy-Related Carbon Emissions Fall to an 18-Year Low," and Natural Gas Nation: EIA Sees U.S. Future Shaped by Fracking.")

Here are a few of the efforts to make fracking greener:

Water-Free Fracking: GasFrac's fracking system, which uses a gelled fluid containing propane, has other advantages besides eliminating the need for water, according to Hill. Because the gel retains sand better than water, it's possible to get the same results with one-eighth the liquid and to pump at a slower rate. Because GasFrac says the amount of hydrocarbon in the gel is comparable to what's in the ground, the fluid can simply merge into the flow being extracted from the ground, eliminating the need to drain contaminated wastewater and haul it away in trucks for disposal, usually at deep-well injection sites. "We present a much smaller footprint," he said. (See related, "Fracking Waste Wells Linked to Ohio Earthquakes.")

Using Recycled Water or Brine: While fracking typically uses freshwater, industry researchers have worked to perfect friction-reducing additives that would allow operators to use recycled "gray" water or brine pumped from underground. Halliburton's UniStim, which went on the market about a year ago, can create a highly viscous fluid from any quality of water, according to Stephen Ingram, the company's technology manager for North America. In northeastern Canada, one producer has tapped into a deep subsurface saline water aquifer for a portion of its supplies for hydraulic fracturing.

Eliminating Diesel Fumes: The diesel-powered equipment used in drilling and pumping wells can be a worrisome source of harmful pollutants such as particulates, as well as carbon emissions that contribute to global warming. And diesel fuel is expensive. Last year, Apache, a Houston-based oil and gas operator, announced it would become the first company to power an entire fracking job with engines using natural gas. In addition to reducing emissions, the company cut its fuel costs by 40 percent. Halliburton has introduced another innovation, the SandCastle vertical storage silo for the sand used in fracking, which is powered by solar panels. The company also has developed natural-gas-powered pump trucks, which Ingram said can reduce diesel consumption on a site by 60 to 70 percent, resulting in "a sizable reduction in both emissions and cost."

Treating Wastewater: At hydraulic fracturing sites, the amount of wastewater typically far exceeds the amount of oil produced. The fluid that returns to the surface through the well bore is not only the chemically treated frack water, but water from the rock formation that can contains brines, metals, and radionuclides. (See related, "Forcing Gas Out of Rock With Water.") That wastewater must be captured and stored on site, and then often is shipped long distances to deep well injection underground storage facilities. There have been few treatment options. But Halliburton has developed the CleanWave treatment system, which uses positively charged ions and bubbles to remove particles from the water at the fracking site. Last September, GE and its partner Memsys also tested a new on-site treatment system that allows the water to be reused without being diluted with freshwater, by employing a desalination process called membrane distillation. (See related Quiz: What You Don't Know About Water and Energy.

Plugging Methane Leaks: A major fracking concern has been whether companies are allowing a significant amount of natural gas to escape, because methane—the main component of natural gas—is a potent greenhouse gas, 34 times stronger than carbon dioxide (CO2). A recent study concluded U.S. methane emissions are likely 50 percent higher than official government estimates. (See related, "Methane Emissions Far Worse Than U.S. Estimates.") New U.S. Environmental Protection Agency regulations that go into effect next year will require that all U.S. oil and gas sites have equipment designed to cut a wide range of pollutants, a step that the agency expects will cut methane. (See related, "Air Pollution From Fracked Wells Will Be Regulated Under New U.S. Rules.")

Methane emissions from onshore oil and natural gas production could be reduced by 40 percent by 2018, at a cost that's the equivalent of just one cent per thousand cubic feet of natural gas produced, concludes a just-released study, conducted by Fairfax, Va.-based consulting firm ICF International for the Environmental Defense Fund. EDF's Ratner said that inspectors equipped with infrared cameras can spot leaks at fracking sites, which can then be plugged. "The cameras cost about $80,000 to $100,000 apiece," he noted. "But that can pay for itself, because the more leaks you fix, the more gas you have to sell." (See related blog post: "Simple Fixes Could Plug Methane Leaks From Energy Industry, Study Finds.")

Another improvement that can reduce methane emissions: Replacing conventional pressure-monitoring pneumatic controllers, which are driven by gas pressure and vent gas when they operate. A U.S.-wide move to lower-bleed designs could reduce emissions by 35 billion cubic feet annually. And switching out conventional chemical injection pumps used in the fracking process, which are powered by gas pressure from the wells, and replacing them with solar-powered pumps, operators could eliminate an 5.9 billion cubic feet of methane emissions annually, the EDF report concludes.

The Cost-Benefit Equation

Some solutions do not require advanced technology. A study released Wednesday by the Boston-based Clean Air Task Force suggests that almost all of the methane leaks from the oil and gas infrastructure could be reduced at relatively little expense, often by simply tightening bolts or replacing worn seals.

A number of greener fracking technologies already are being implemented, according to industry officials. But one obstacle is economic. The newer, more environmentally friendly technologies generally cost more than the legacy equipment they would replace. Extracting natural gas with water-free fracking, for example, could cost 25 percent more than conventional fracking, according to David Burnett, a professor of petroleum engineering at Texas A&M University who heads that school's Environmentally Friendly Drilling Systems Program. He said that switching fracking equipment from diesel to natural gas is the innovation that's catching on most rapidly, because it provides a clear economic benefit as well as helping to lower carbon emissions. With the rising cost of renting fracking rigs, companies are eager to find improvements that will reduce their costs, he said.

Green fracking is "the same as with any industry—if you come out with a game-changing technology, you can get in the market first and ride that," Burnett said. (See related, "Can Natural Gas Bring Back U.S. Factory Jobs?")

But Halliburton's Ingram said that innovations such as chemical treatments to make brine usable will drop in price as the technology is perfected. "Eventually it will become the lower-cost chemistry," he said.

A more difficult hurdle might be overcoming what Ingram calls "sociopolitical constraints" around the country. One major issue that reduces incentives to invest in green fracking innovations: the generally low price of freshwater. (See related, "Water Demand for Energy to Double by 2035.")

Source: This story is part of a special series that explores energy issues. For more, visit The Great Energy Challenge .

Thursday, April 3, 2014

Israeli solar plant is now 100 percent self-cleaning

The dusty desert environments where many solar plants are located can make their photovoltaic arrays dirty and reduce their effectiveness. Cleaning the panels can be a time-consuming and expensive process. An Israeli solar plant is now said to be the first to have fully-automated cleaning in place.

Ketura Sun was the first commercial solar field in Israel. It spans 8 hectares (20 acres) and produces 9 million kilowatt-hours of electricity each year. Located in the Negev desert, the plant is jointly owned by Siemens AG and Arava Power, which is Israel's leading solar developer.

Due to the expense of cleaning the Ketura Sun panels manually, the process was only carried out nine times a year, meaning the plant was mostly operating in a state of dusty inefficiency. Each cleaning process took five days and meant that efficiency was further reduced as crews carried out the work. Damage to the sensitive equipment was also a risk.

Now, the panels at Ketura Sun are being cleaned nightly by a fleet of almost 100 water-free, energy-independent robots. The Ecoppia E4 robots are mounted on a frame that moves laterally along the panels and the robots themselves move up and down the panels. They use a rotating brush made up of soft microfiber in conjunction with air blowers to remove what Ecoppia says is 99 percent of dust build-up.

This approach means that no water is required, unlike the Heliotex solar cleaning system, avoiding the need to pipe a potentially limited resource to the devices. The robots also use their own solar panels and energy-recovery systems to generate the power they need to operate. As such, they are completely self-contained and independent.

Ecoppia says that dust accumulation on solar panels (or "soiling") can reduce the energy output of panels by up to 35 percent. By removing up to 99 percent of dust on a nightly basis, its E4 robots can help to keep the panels at near-optimum performance constantly.

The video below shows the Ecoppia E4 robots in action..

https://www.youtube.com/watch?feature=player_embedded&v=kBjS95-ALTc

Source: Ecoppia

Monday, March 31, 2014

Meeting climate targets may require reducing meat, dairy consumption

Date: March 30, 2014

Geenhouse gas emissions from food production may threaten the UN climate target of limiting global warming to 2 degrees Celsius, according to research at Chalmers University of Technology, Sweden.

On Monday 31 March the Intergovernmental Panel on Climate Change (IPCC) presents their report on the impacts of climate change.

Carbon dioxide emissions from the energy and transportation sectors currently account for the largest share of climate pollution. However, a study from Chalmers now shows that eliminating these emissions would not guarantee staying below the UN limit. Emissions from agriculture threaten to keep increasing as global meat and dairy consumption increases. If agricultural emissions are not addressed, nitrous oxide from fields and methane from livestock may double by 2070. This alone would make meeting the climate target essentially impossible.

"We have shown that reducing meat and dairy consumption is key to bringing agricultural climate pollution down to safe levels," says Fredrik Hedenus, one of the study authors. "Broad dietary change can take a long time. We should already be thinking about how we can make our food more climate friendly."

By 2070, there will be many more of us on this planet. Diets high in meat, milk, cheese, and other food associated with high emissions are expected to become more common. Because agricultural emissions are difficult and expensive to reduce via changes in production methods or technology, these growing numbers of people, eating more meat and dairy, entail increasing amounts of climate pollution from the food sector.

"These emissions can be reduced with efficiency gains in meat and dairy production, as well as with the aid of new technology," says co-author Stefan Wirsenius. "But the potential reductions from these measures are fairly limited and will probably not suffice to keep us within the climate limit, if meat and dairy consumption continue to grow."

Beef and lamb account for the largest agricultural emissions, relative to the energy they provide. By 2050, estimates indicate that beef and lamb will account for half of all agricultural greenhouse gas emissions, while only contributing 3 percent of human calorie intake. Cheese and other dairy products will account for about one quarter of total agricultural climate pollution.

Source: Chalmers University of Technology

Friday, March 28, 2014

Superparamagnetic" particles used to harvest phosphorus from polluted water

NYCU

Photo: A demonstration of how the phosphorus-laden particles can be removed from water using a magnet

Phosphorus is a mineral that's widely used in fertilizer, which itself has an unfortunate tendency to leach out of farmers' fields and into our waterways. Now, researchers from Germany's Fraunhofer Institute for Silicate Research have devised a method of retrieving some of that phosphorus from the water – thus both reducing pollution, and providing a source of reclaimed phosphorus.

The Fraunhofer team has been using superparamagnetic particles, which are ordinarily non-magnetic, but that turn magnetic when exposed to a magnetic field. These particles also contain bonding sites for phosphorus, and are added to phosphorus-polluted water. When this happens, the phosphorus anions in the water bond with the particles.

The particles, along with the attached anions, are then removed from the water simply using a magnet. Once the removed particles are in turn removed from the magnetic field, they de-magnetize and release the phosphorus for subsequent re-use. The water, meanwhile, is left phosophorus-free.

Apparently the technology could be tweaked to remove other types of pollutants, such as heavy metals, by applying different types of bonding sites to the particles.

Fraunhofer developed the system in collaboration with the University of Stuttgart.

Source: Fraunhofer

Thursday, March 13, 2014

Blue Diversion Toilet is Flushed with Success

Blue Diversion Toilet is Flushed with Success

NYCU

The Closed-System Blue Diversion Toilet is designed for Off-grid Use

Two years ago, an off-grid closed-system toilet known as the Diversion won an award at the Bill & Melinda Gates Foundation's "Reinventing the Toilet" fair. Created by the Swiss Federal Institute of Aquatic Science and Technology (Eawag) and now called the Blue Diversion, it recently also won the title of Most Innovative Project (Europe/West Asia), as bestowed by the International Water Association. So, what makes it so special? Well, for one thing, the same water that flushes it is subsequently used in its hand-washing sink.

Here's how the Blue Diversion works ...

Feces, urine, and flush water are separated right below the toilet bowl. The first two items are then stored in sealed compartments, for subsequent use as fertilizer. The water, because it's used more to rinse out the bowl than to actually transport the waste, isn't as contaminated as what goes down a regular toilet's pipes. It's still pretty disgusting, though, so it's pumped into a filtration system in the back wall of the setup.

There, it passes through a bioreactor that neutralizes organic matter and ammonia, along with an ultrafiltration membrane that blocks pathogenic organisms such as bacteria and viruses. Any remaining trace amounts of organic matter and ammonia are then neutralized by an electrolysis unit, which also produces chlorine to disinfect the water.

From there, gravity carries the water down to be used in the sink, in a bidet-style shower head, or to rinse out the bowl once again. According to Eawag, the same water is good for about 50 uses per day. Power for the pumps, electrolysis unit and electronics are provided by a top-mounted photovoltaic panel.

NYCU

Although the whole water-reuse thing may still sound kind of ... yucky to some people, the Blue Diversion has reportedly been successfully field-tested in Uganda and Kenya. Eawag is currently looking for industrial partners to help with large-scale production, and hope to sell it for use in developing nations and off-grid locations for about US$500 per unit.

... and should you not be into squatting, a sit-down version is due to come out next year.

Source: Eawag, Blue Diversion.