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Comment Wind and Solar Converge (Score 5, Informative) 262

by mdsolar (#49249623) Attached to: US Wind Power Is Expected To Double In the Next 5 Years
I recently noticed an interesting convergence. The long term growth of both solar and wind capacity is exponential. The growth rate for solar is higher than for wind power but wind power is currently ahead in capacity. If we take a capacity factor of 20% for solar and 30% for wind, how long does it take to cover the roughly 20 TW of world energy demand?

For solar, taking 200 MW of capacity in 1995 and 100,000 MW in 2012 http://en.wikipedia.org/wiki/G... we get to 100,000,000 MW in 39 years from 1995 since (log(100 TW)-log(200 MW))/(log(100,000 MW)-log(200 MW))/17 years)=39 years. So 2034 is when we may expect solar PV to cover all energy demand.

For wind, taking 7,600 MW of capacity in 1995 and 369,553 MW in 2014 http://www.gwec.net/wp-content... we get to 60,000,000 MW in 39 years from 1997 since (log(60 TW)-log(7,600 MW))/(log(369,533 MW)-log(7.500 MW))/17 years = 39 years. So, 2036 is where we may expect wind power to cover all energy demand.

So, within just a couple years of each other, either technology can be projected to grow to cover all current demand.

A driver for ongoing exponential growth for PV is the still falling cost of manufacture. It is expected that panels will cost $0.36/W to produce in 2017. http://www.greentechmedia.com/...

This seems to be a faster rate than pledges coming in for Paris are anticipating so we might have some confidence that those pledges are going to be met.

Submission + - In Historic Turn, CO2 Emissions Flatline in 2014, Even as Global Economy Grows (forbes.com)

Submitted by mdsolar
mdsolar writes: A key stumbling block in the effort to combat global warming has been the intimate link between greenhouse gas emissions and economic growth. When times are good and industries are thriving, global energy use traditionally increases and energy-related carbon dioxide emissions also go up. Only when economies stumble and businesses shutter — as during the most recent financial crisis — does energy use typically decline, in turn bringing down planet-warming emissions.

But for the first time in nearly half a century, that synchrony between economic growth and energy-related emissions seems to have been broken, according to the Paris-based International Energy Agency, prompting its chief economist to wonder if an important new pivot point has been reached — one that decouples economic vigor and carbon pollution.

The IEA pegged carbon dioxide emissions for 2014 at 32.3 billion metric tons — essentially the same volume as 2013, even as the global economy grew at a rate of about 3 percent.

“This gives me even more hope that humankind will be able to work together to combat climate change, the most important threat facing us today,” the IEA’s lead economist, Fatih Birol, said in a statement accompanying the findings.

Whether the disconnect is a mere fluke or a true harbinger of a paradigm shift is impossible to know. The IEA suggested that decreasing use of coal in China — and upticks in renewable electricity generation there using solar, wind and hydropower — could have contributed to the reversal. The agency also cited the ongoing deployment of energy-efficiency and renewable power policies in Europe, the U.S. and other developed economies as additional factors.

Comment NYT reports: (Score 1) 2

by mdsolar (#49216129) Attached to: NY Times removes ex President Bush from Selma Bridge picture
"Joining Mr. Obama on Saturday was former President George W. Bush, who signed the reauthorization of the Voting Rights Act in 2006, as well as more than 100 members of Congress. About two dozen of them were Republicans, including the House majority leader, Kevin McCarthy of California. While sitting onstage, Mr. Bush made no remarks, but rose to his feet to applaud Mr. Obama, and the two men hugged afterward." http://www.nytimes.com/2015/03...

Submission + - California's hot, dry winters tied to climate change (arstechnica.com) 1

Submitted by mdsolar
mdsolar writes: Climate change is one of the most prominent public health issues currently on the CDC’s radar. The organization's Climate and Health Program attempts to help state and city health departments to prepare for the health impacts of climate change, which can come in the form of things like temperature extremes, air pollution, allergens, and changes in disease patterns; they can also be felt indirectly through issues like food security.

Are we seeing some of these effects already? Since 2012, California has been in the midst of a record-setting drought, with extremely warm and dry conditions characterizing the last three years in that state. A new paper published in the Proceedings of the National Academy of Sciences concludes that warming caused by humans is responsible for the conditions that have led to this California drought.

This study, published by scientists affiliated with the Department of Environmental Earth System Science and the Woods Institute for Environment at Stanford University, used historical statewide data for observed temperature, precipitation, and drought in California. The investigators used the Palmer Hydrological Drought Index (PHDI) and the Palmer Drought Severity Index (PDSI), collected by the National Climatic Data Center, as measures of the severity of wet/dry anomalies. They also used global climate model simulations from the Coupled Model Intercomparison Project (CMIP) to compare historical predictions for anthropogenic and non-anthropogenic historical climates.

The authors performed their analysis using an approach called bootstrapping. Bootstrapping techniques allow statisticians to utilize the same sample repeatedly to improve their estimates of specific effects. In this analysis, bootstrapping was used to compare the climate data with measures of populations from different time periods to allow for analysis of how changes in population are associated with different climate conditions.

This analysis found that the statewide warming in California occurs in climate models that include both natural and human factors, but not in simulations that only include natural factors. It's a difference with a very high (0.001) level of statistical significance.

Submission + - Nuclear waste, arsenic at SC coal plant raise concern (thestate.com)

Submitted by mdsolar
mdsolar writes: Just a few hundred yards from Lake Robinson lies an old waste pond that, until this year, was among the least of Duke Energy’s worries in the Carolinas.

The pond had virtually dried up and, as coal ash basins go, didn’t appear to present the same threat to groundwater, rivers or lakes that other ash basins do, environmentalists say.

But documents that have surfaced recently show the unlined 55-acre basin has leaked arsenic – and it has the unusual legacy of being a dump site for low-level nuclear waste. Both findings are producing new questions about how to cleanse the mess at Duke Energy’s H.B. Robinson power station.

Pollution test results from last year show that the Hartsville plant’s coal waste pond has released higher levels of arsenic into groundwater than state regulators ever had recorded there. In some cases, the arsenic levels rival those at other power plant sites in South Carolina that already are undergoing cleanup.

And in the 1980s, at least 69,000 cubic meters of radiation-tinged sediment wound up in the coal ash pond from the nuclear plant, a rare occurrence because most power plants don’t include both coal-and nuclear-fired units.

State regulators in South Carolina said they knew of no other power plant site where atomic waste wound up in a coal ash pond. A spokesman for the Nuclear Regulatory Commission in Atlanta said the practice is rare.

Submission + - Mars Had an Ocean, Scientists Say, Pointing to New Data (nytimes.com)

Submitted by mdsolar
mdsolar writes: After six years of planetary observations, scientists at NASA say they have found convincing new evidence that ancient Mars had an ocean.

It was probably the size of the Arctic Ocean, larger than previously estimated, the researchers reported on Thursday. The body of water spread across the low-lying plain of the planet’s northern hemisphere for millions of years, they said.

If confirmed, the findings would add significantly to scientists’ understanding of the planet’s history and lend new weight to the view that ancient Mars had everything needed for life to emerge.

Submission + - Fastest Star Ever Seen Will Escape from the Galaxy (discovery.com)

Submitted by astroengine
astroengine writes: The compact star US 708 hasn’t had an easy life. Paired with a domineering partner, 708’s mass was siphoned away, reducing it to a dense, helium-filled core. But 708 didn’t go quietly into the night. Instead, scientists believe the feeding frenzy ended in a supernova explosion that catapulted the ravaged remains with such force it’s leaving the galaxy. Fast. A new study shows that the star, classified as a hot subdwarf, is blasting through the Milky Way at about 750 miles per second, faster than any other star in the galaxy.

Submission + - Germany says using tax money for nuclear power 'out of the question' (reuters.com) 1

Submitted by mdsolar
mdsolar writes: Using taxpayers' money to fund nuclear power is "absolutely out of the question", German Economy Minister Sigmar Gabriel said on Thursday, in an apparent swipe at British plans to finance new atomic generation.

Gabriel was arriving for talks in Brussels on the European Commission's proposal for an energy union, which would deepen cross-border cooperation on energy across the 28-member EU.

Previous efforts to harmonize energy policy have faltered as member states have jealously guarded their right to decide on the kind of energy they use.

Germany's decision to phase out nuclear power sets it at odds with plans by Britain and France to invest in the emissions-free fuel source, which they say plays a major role in combating climate change.

Germany has instead focused on renewable energy, such as wind and solar.

"There are countries in the EU that want to support nuclear power with tax money. We think that is absolutely out of the question," Gabriel said.

"We will not agree by any means that nuclear energy be supported by public money. Nuclear energy is the most expensive kind of generation. It has now been around for 50 years, it is not new and it is dangerous."

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