Monthly Archives: September 2013

Global Warming – Paused or Peaked? – draft U.N. report

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OSLO (Reuters) – A “hiatus” in global warming so far this century is partly caused by natural variations in a chaotic climate and is unlikely to last, a draft United Nations report by leading climate scientists says.

Duane Tilden‘s insight:

>The fact that temperatures have risen more slowly in the past 15 years despite rising emissions of greenhouse gases has emboldened sceptics who challenge the evidence for man-made climate change and question the need for urgent action.

But the IPCC draft reports do not project any long-term respite. Instead, they forecast a resumption in the warming trend that is likely to cause ever more heatwaves, droughts, floods and rising sea levels. […]

“There are a number of explanations (for the hiatus), any one of which might be correct,” said professor Myles Allen of Oxford University, who contributed to the IPCC draft. “That is very different from saying:’We have no idea what’s going on’.”

The drafts say that a reduction in warming for 1998-2012 compared to 1951-2012 is “due in roughly equal measure” to natural variations in the climate and factors such as “volcanic eruptions and the downward phase of the current solar cycle.”<

See on news.yahoo.com

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

Water Energy Nexus: A Literature Review

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Water-Energy Nexus: A Literature Review provides readers with an overview and analysis of the policy, scientific and technical research on the connections between water and energy. This review is a comprehensive survey of the literature from the academic, government and nonprofit sectors, organized around the water and energy life cycles.  It examines research and policy from energy use across the water and wastewater sectors, as well as water across the various components of the energy sector.
See on waterinthewest.stanford.edu

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

Revisiting The North American Hydropower Opportunity

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It is no secret that many renewable energy advocates are not in favor of large hydropower.

Duane Tilden‘s insight:

>[…] there exists a threat that is even more worrisome to endangered species, a threat that has the potential to cause destructive flooding and destroy ecosystems: climate change.  […]

Perhaps that’s why in May of this year, the World Bank reversed its stance on large-scale hydropower. Whereas the major international development bank was once a staunch opponent of large-scale hydro, recognition that developing regions like Africa and Southeast Asia desperately need power have forced it to reconsider.  The world needs energy to lift people out of poverty and building more fossil fuel-fired electricity plants will only serve to exacerbate the problems already associated with climate change. Hydropower is an answer.

Maybe it is time for the renewable energy industry to take a second look at hydropower development. The clean energy it can provide is a vast improvement over the dirty energy we get from fossil fuels. Hydropower already meets about 8 percent of U.S. electricity demand and with improved technologies that already exist the National Hydropower Association (NHA) estimates that we can double the amount of energy we get from hydropower without building any more dams.<

See on www.renewableenergyworld.com

Google obtains a Renewable Energy Power Purchase Agreement in Texas

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Duane Tilden‘s insight:

>The structure of this agreement is similar to our earlier commitments in Iowa and Oklahoma. Due to the current structure of the market, we can’t consume the renewable energy produced by the wind farm directly, but the impact on our overall carbon footprint and the amount of renewable energy on the grid is the same as if we could consume it. After purchasing the renewable energy, we’ll retire the renewable energy credits (RECs) and sell the energy itself to the wholesale market. We’ll apply any additional RECs produced under this agreement to reduce our carbon footprint elsewhere.<

See on googleblog.blogspot.ca

Boston Leads Ranking of Energy-Efficient U.S. Cities by ACEEE

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A new ranking highlights Boston’s achievements in conserving energy as the Senate debates a bipartisan energy efficiency bill.

Duane Tilden‘s insight:

>ACEEE graded 34 cities for their efforts in five areas: buildings, transportation, energy and water utility programs, local government operations, and community-wide initiatives.  […]

The cities’ leap forward in energy-efficiency efforts has been a stark contrast to the slow movement on Capitol Hill, where the Energy Savings and Industrial Competitiveness Act of 2013, authored by Sen. Jeanne Shaheen (D-New Hampshire) and Sen. Rob Portman (R-Ohio) has been struggling to move forward.

The bill, […] would require the federal government—the nation’s single largest energy consumer—to update government buildings to improve energy efficiency, institute electricity-saving measures for government computers, and make it easier for agencies to switch to electric and natural-gas-powered vehicles. It also would provide training for workers in how to build more energy-efficient buildings for the private sector, and help finance private-sector renovations for energy efficiency. […]<

See on news.nationalgeographic.com

Developing an Energy Management Program for Your Business

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Today more than ever, businesses are concerned with maximizing operational efficiency, minimizing costs, and seeking out untapped revenue streams. At the same

Duane Tilden‘s insight:

>Large energy users like many commercial, institutional, and industrial organizations have a unique opportunity to act as a “virtual power plant” while reducing their real-time demand for electricity—and opening up a new revenue stream. This strategy, known as demand response, is not only a cost-free way to reduce energy usage, but also it generates payments for participating businesses simply for being on call.

Demand response providers work with commercial, institutional, and industrial businesses to identify ways for facilities to reduce energy consumption without affecting business operations, comfort, or product quality. In turn, those facilities agree to reduce their demand during strategic times so that utilities and grid operators can improve reliability during times of peak demand. Demand response also helps increase economic efficiency in regional energy markets and integrate renewable generation capacity into generation systems.

Demand response can be considered a form of strategic energy efficiency, but what about long-term, persistent energy efficiency, a second key to a comprehensive energy management program? In even the most high-tech, LEED Platinum certified buildings, it can be very difficult to ensure efficient operation over time. […]<

See on www.dailyenergyreport.com