Category: Energy Matters

Climate change puts us all in the same boat. One hole will sink us

admin /11 December, 2009

Climate change puts us all in the same boat. One hole will sink us all

Global warming does not respect borders. A mindset shift is required if world leaders are to save us from ourselves.

 

 

 

The UN climate change conference in Copenhagen offers the prospect of a robust political deal, endorsed by the world’s leaders and witnessed by the world’s people, that sets out clear targets and a timeline for translating it into law. To be a truly historic achievement, such a deal must do two things.

 

First, it must lay the basis for a global regime and subsequent agreements that limit global temperature rise in accordance with the scientific evidence. Second, it must provide clarity on the mobilisation and volume of financial resources to support developing countries to adapt to climate change.

 

The stakes are enormous. Economic growth has been achieved at great environmental and social cost, aggravating inequality and human vulnerability. The irreparable damage that is being inflicted on ecosystems, agricultural productivity, forests and water systems is accelerating. Threats to health, life and livelihoods are growing. Disasters are also increasing in scale and frequency.

DC Arc Faults and PV System Safety

admin /9 December, 2009

December 7, 2009

DC Arc Faults and PV System Safety

by Marv Dargatz, Enphase Energy Inc.

Within the PV industry, the risk presented by DC arc faults is gaining significant attention, and for good reason. The DC circuits within a PV installation can generate, and sustain, arcs of considerable intensity. Not only have these arcs started fires, but the intensive energy that generates these arcs also poses a significant risk to firefighters during their efforts to suppress the fire.

Reliable detection of arc faults is a serious challenge, and determination of the appropriate corrective action is difficult.  PV system design philosophy has a significant impact on both prevention and suppression of fires, with an increasing preference being given to AC-based systems that mitigate the risk of fire by avoiding distribution of high DC voltage and high DC current altogether.

An Exclusive Look at the New Siemens 3-MW Direct Drive Turbine

admin /4 December, 2009

December 3, 2009

An Exclusive Look at the New Siemens 3-MW Direct-Drive Turbine

by Eize de Vries, Wind Technology Correspondent
Brande, Denmark [RenewableEnergyWorld.com]

Little over a year after Siemens erected its first 3.6-MW direct-drive “Proof of Concept” wind turbine, this November the company presented a new rather different 3-MW direct-drive concept. RenewableEnergyWorld.com was exclusively invited to the Brande HQ in Denmark to view the prototype and discuss the new turbine with Siemens CTO Henrik Stiesdal. A prototype was erected near Brande during the first week of December.

Our expectations were therefore that a direct-drive concept mainly offers a commercially viable alternative for large offshore turbines. However, we now have sufficient indications that the concept might also be feasible for the high-end high-volume market, and do hope that this machine will prove competitive with our 2.3-MW volume turbine series.’

Designs for new UK nuclear reactors are unsafe

admin /27 November, 2009

Designs for new UK nuclear reactors are unsafe Terry Macalister 27th November, 2009 Major setback for nuclear energy plans as watchdog’s report finds flaws in US and French models Britain’s main safety regulator threw the government’s energy plans into chaos tonight by damning the nuclear industry’s leading designs for new plants. The Health and Safety Continue Reading →

Solar’s rapid evolution makes energy planners rethink the grid

admin /24 November, 2009

 

Solar’s rapid evolution makes energy planners rethink the grid 43

 
 

Powerlines.Photo courtesy OZinOH via Flickr California’s ambitious goal of obtaining a third of its electricity from renewable sources by 2020 has spawned a green energy boom with thousands of megawatts of solar, wind, and biomass power plants planned for … the middle of nowhere.

And therein lies the elephant in the green room: transmission. Connecting solar farms and geothermal plants in the Mojave Desert and wind farms in the Tehachapis to coastal metropolises means building a massive new transmission system. The cost for 13 major new power lines would top $15.7 billion, according to a report released in August by the state’s Renewable Energy Transmission Initiative.

SolarReserve’s 24/7 solar plant

admin /17 November, 2009

SolarReserve’s 24/7 solar power plant 69

(Or Should iit be Salt Power. )

Photo: SolarReserveAt Rocketdyne’s San Fernando Valley headquarters outside Los Angeles there’s a whiff of the right stuff—of crew-cut guys in short-sleeve white shirts and skinny black ties—in a vast room that holds the massive rocket engines that propelled John Glenn and the Apollo 11 crew into space.

In one corner of this corporate space museum stands something different, though. It’s a scale model of a solar power tower, technology Rocketdyne developed a couple of decades ago as a spinoff of its work for NASA.

Here’s how it works: An array of mirrors called heliostats focuses sunlight on a receiver filled with molten salt; the stored heat can produce steam to run a solar power plant 24/7—the elusive Holy Grail of solar energy. The technology, cast off as a non-commercial curiosity in the age of $18-a-barrel oil, is now being revived and could make Rocketdyne and its parent company, United Technologies, a big player in green tech.

A Santa Monica startup called SolarReserve—founded by, yes, rocket scientists from Rocketdyne—has licensed the solar power tower technology, turning the Silicon Valley model on its head: Take a proven yet obscure technology developed years ago by an old-line tech company and marry it to the entrepreneurial culture of a startup.  

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