Tag Archives: Engineering

U.S. Tidal Energy Project requires Proximity Standard

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A planned tidal energy project off the coast of Washington state in the US has come under fire over the lack of a standard defining how close such projects can be to existing underwater cables.

Duane Tilden‘s insight:

>There is currently no U.S. standard for the distance tidal energy projects need to be from other subsea installations. The Federal Communications Commission has stated that neither it nor FERC has the expert guidance necessary to make an informed decision about what a safe separation distance would be. The FCC has charged an advisory committee, the Communications Security, Reliability and Interoperability Council (CSRIC), to work with the industry to develop guidance, delegating a special submarine cable working group to address the issue.

Distance guidelines do exist for offshore wind turbines in the U.S. The FCC and industry groups have suggested that these standards, which require 500 metres between offshore wind turbines and submarine cables, should be used in this case.

In its comment to the FERC, Pacific Crossing invoked a UK guideline, Subsea Cables UK Guideline number 6, which recommends proximity limits of 200-400 metres from an existing subsea structure for marine energy development. The North American Submarine Cable Association has urged U.S. regulatory agencies to apply the UK guidelines to all U.S. marine energy projects, including tidal energy projects.<

See on www.renewableenergyworld.com

GE seeks to Clean up Fracking’s Dirty Water Problem

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GE has demonstrated technology aimed at addressing one of the biggest challenges with fracking: water pollution.

Duane Tilden‘s insight:

>Concerns about water pollution and other environmental issues related to fracking have led some places, including France and New York State, to block the process. As fracking increases in dry areas and places that lack adequate treatment and disposal options, pressure to block it could grow.

“Water-treatment technology is going to become more and more critical as the industry moves forward,” says Amy Myers Jaffe, executive director of energy and sustainability at the University of California at Davis, and a new member of a GE environmental advisory board. She says the continued use of fracking depends on the “industry getting its act together to do it in an environmentally sustainable way.”

Better water-treatment options could change the way oil and gas producers operate by making it economical to treat water at fracking sites instead of trucking it long distances to large water-treatment facilities or disposal wells. The technology is specifically targeted to places such as the Marcellus shale, one of the largest sources of shale gas in the U.S., where wastewater is far too salty for existing on-site treatment options (see “Can Fracking Be Cleaned Up?” and “Using Ozone to Clean Up Fracking”).

Each fracking well can require two to five million gallons of fresh water, which is pumped underground at high pressure to fracture rock and release trapped oil and gas. Much of that water flows back out, carrying with it the toxic chemicals used to aid the fracking process, as well as toxic materials flushed from the fractured rock.

Producers currently reuse much of that water, but that involves first storing it in artificial ponds, which can leak, and then diluting it, a step that consumes millions of gallons of fresh water. Eventually they can’t reuse the water any more so they need to ship it, often over long distances, to specialized treatment and disposal locations. Transporting the wastewater is expensive, and it comes with a risk of spills. At disposal sites, the wastewater is injected deep underground in a process that can cause earthquakes.

The new technology would make it unnecessary to dilute the wastewater, or transport it for treatment or disposal. […]<

See on www.technologyreview.com

Greening the Internet: Sustainable Web Design

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Do you know your website’s carbon footprint? Or how to lower it?

Duane Tilden‘s insight:

>A growing number of industries are trying to reduce or at least curtail carbon footprints and energy use. Emissions standards have been set for the automotive, construction, and even telecommunications industries. Yet the internet’s carbon footprint is growing out of control: a whopping 830 million tons of CO2 annually, which is bigger than that of the entire aviation industry. That amount is set to double by 2020.

It is time for web designers to join the cause.

Right now, at least 332 million tons of CO2—40 percent of the internet’s total footprint—falls at least partially under the responsibility of people who make the web. It needn’t be that large, but with our rotating carousels, high-res images, and more, we have been designing increasingly energy-demanding websites for years, […]<

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World Record Solar Cell with 44.7 Percent Efficiency (news)

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Freiburg, Germany – The Fraunhofer Institute for Solar Energy Systems ISE, Soitec, CEA-Leti and the Helmholtz Center Berlin jointly announced on late Monday having achieved a new world record for the conversion of sunlight into electricity using a new solar cell structure with four solar subcells. …

Duane Tilden‘s insight:

>These solar cells are used in concentrator photovoltaics (CPV), a technology which achieves more than twice the efficiency of conventional PV power plants in sun-rich locations. The terrestrial use of so-called III-V multi-junction solar cells, which originally came from space technology, has prevailed to realize highest efficiencies for the conversion of sunlight to electricity. In this multi-junction solar cell, several cells made out of different III-V semiconductor materials are stacked on top of each other. The single subcells absorb different wavelength ranges of the solar spectrum.<

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Climate change & Global warming: IPCC issues warning to Governments

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Call to ‘stop dithering about fossil fuel cuts’ as expert panel warns entire globe is affected

Duane Tilden‘s insight:

>The scientists’ warning – the most comprehensive and convincing yet produced by climate scientists – comes at a time when growing numbers of people are doubting the reality of global warming. Last week, the UK Energy Research Centre (UKERC) published a survey showing that the proportion of British people who do not think the world’s climate is changing has almost quadrupled since 2005.

Asked if they thought Earth’s climate was changing, 5% of respondents said “no” in 2005, a figure that rose to 11% last year and reached 19% this year.

But as the IPCC report underlines, scientists are becoming more and more certain that climate change poses a real danger to the planet.

Many believe the disconnection between popular belief and scientific analysis has been engineered by “deniers” explicitly opposed to the lifestyle changes – including restrictions on fossil fuel burning – that might be introduced in the near future.

“There are attempts by some politicians and lobbyists to confuse and mislead the public about the scientific evidence that human activities are driving climate change and creating huge risks,” said Stern.

“But the public should be wary of those who claim they know for certain that unmanaged climate change would not be dangerous. For they are not only denying 200 years of strong scientific evidence – the overwhelming view of the world’s scientific academies and over 95% of scientific papers on the subject – but they are often harbouring vested interests or rigid ideologies as well.”

The report will be discussed this week by political leaders meeting in Stockholm. The study – the work of more than 200 scientists – outlines the physical changes that are likely to affect Earth’s climate this century.<

See on www.theguardian.com

India’s First LEED’s Green Building targets “Net Zero” with High Efficiency Solar Power

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New Delhi, India (SPX) Sep 19, 2013 – SunPower has announced that Swadeshi Civil Infrastructure has completed the installation of a 930-kilowatt (kW) SunPower solar system on the rooftop of the Indira Paryavaran Bhavan building…

Duane Tilden‘s insight:

>The state-of-the art landmark will be India’s first net zero energy building. Its design emphasizes conservation featuring trees to reduce adverse environmental impact, adequate natural light and shaded landscaped areas to reduce ambient temperature.

The building is targeted to achieve Platinum from the Leadership in Energy and Environmental Design green building rating system, known as LEED INDIA. It also is expected to receive a five star Green Rating for Integrated Habitat Assessment from the rating system developed by the Energy and Resource Institute and supported by the Ministry of New and Renewable Energy, the nodal ministry of Indian government.<

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Energy from tides and currents: Arranging underwater Tidal Sails

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In the long sprint to find new sources of clean, low-cost power, slow and steady might win the race — the slow-moving water of currents and tides, that is.

Duane Tilden‘s insight:

>The system, developed by a Norwegian company called Tidal Sails AS, consists of a string of submerged blades or sails, connected via wire ropes, angled into the oncoming current. The rushing current generates large lift forces in the sails, and as they are pushed along through a continuous loop, they drive a generator to produce electricity. […]

In their analysis, the researchers found that the maximum amount of power could be generated using blades with a chord length (the width of the blade at a given distance along its length) equal to the separation between each individual blade, that are positioned at about a 79 degree angle relative to the oncoming current, and that move at a speed about one and half times faster than the current.<

See on www.sciencedaily.com

UK government rejects current Severn tidal barrage plans

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Ministers say major changes must be made to the scheme if it is to be revived and given serious consideration

Duane Tilden‘s insight:

>Concerns over the impact of such a barrage on marine life played a major part in the rejection, with the government agreeing with MPs that better studies were needed to establish the effects on fish.

The response was: “It is for the developers to do the necessary work to prove that their design is ‘fish-friendly’ and will not jeopardise the UK’s obligations under the water framework directive and habitats directive. Such studies will need to take account of the wide variation in vulnerability of different fish species arising from to their different morphology, physiology and behaviour.”

The government said Hafren would need to provide much more detailed, credible evidence of the proposal, including a study of the environmental impacts and information on turbines, as well as information on allaying fears of flooding that could be worsened by any barrage. The coalition said it would consider the proposal further if this information was provided, but added that legal hurdles would mean the consortium’s current proposals were likely to be subject to delay.

Ministers reiterated their view that there should be no firm commitments of public financial support – in the form of the “strike price” of a premium for low-carbon power that has been confirmed for wind power and is expected soon for nuclear energy – for tidal barrage schemes until 2019 at the earliest.<

See on www.theguardian.com

The Dark Side of Efficiency

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zsturm's avatarInnovation in Business, Energy, and Environment

By Peter Brooks

In at least three of the cases we have studied so far (Maersk, Groom, Wal-Mart) efficiency was the one thing everyone seemed to agree on.  Investments in greater resource efficiency (energy, water, space) that cost less than future benefits are no-brainers; a company can save money while also preserving precious, finite resources (to say nothing of the safety, regulatory, aesthetic, and morale benefits of finding and fixing inefficiencies) and that is unequivocally a good thing.

Unfortunately there is a dark side to efficiency: it can be more destructive to the environment and speed the withdrawal and consumption of natural resources than if the investment were never made.  In the late 19th century, an English economist, William Jevons, made the startling discovery that technological improvements that increased the efficiency of coal-burning, led to an increased consumption of coal.  To put it another way, greater efficiency was used…

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Stanford Scientists Analyse Life Cycle Costs of Energy Storage vs Curtailment for Renewables

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Stanford CA (SPX) Sep 17, 2013 –
Renewable energy holds the promise of reducing carbon dioxide emissions. But there are times when solar and wind farms generate more electricity than is needed by consumers.

Duane Tilden‘s insight:

>”We calculated how much energy is used over the full lifecycle of the battery – from the mining of raw materials to the installation of the finished device,” Barnhart said. “Batteries with high energetic cost consume more fossil fuels and therefore release more carbon dioxide over their lifetime. If a battery’s energetic cost is too high, its overall contribution to global warming could negate the environmental benefits of the wind or solar farm it was supposed to support.”

For this study, he and his colleagues calculated the energetic cost of grid-scale photovoltaic solar cells and wind turbines.

“Both wind turbines and photovoltaics deliver more energy than it takes to build and maintain them,” said GCEP postdoctoral scholar Michael Dale, a co-author of the study. “However, our calculations showed that the overall energetic cost of wind turbines is much lower than conventional solar panels, which require lots of energy, primarily from fossil fuels, for processing silicon and fabricating other components.” […]

To find out, the researchers compared the energetic cost of curtailing solar and wind power, versus the energetic cost of grid-scale storage. Their calculations were based on a formula known as “energy return on investment” – the amount of energy produced by a technology, divided by the amount of energy it takes to build and maintain it.

Using that formula, the researchers found that the amount of energy required to create a solar farm is comparable to the energy used to build each of the five battery technologies. “Using batteries to store solar power during periods of low demand would, therefore, be energetically favorable,” Dale said.

The results were quite different for wind farms. The scientists found that curtailing wind power reduces the energy return on investment by 10 percent. But storing surplus wind-generated electricity in batteries results in even greater reductions – from about 20 percent for lithium-ion batteries to ?more than 50 percent for lead-acid.<

See on www.solardaily.com