Thanks to DRS
Archive for the ‘solar’ Category
when I tried to copy video name I got the same AD tab as http://wp.me/pyh3m-42A
SAW “Solar FREAKIN’ Roadways” ( 7min but worth it) on facebook, where the poster wrote, “I posted this a year ago because it was irresistible on so many levels. It still is ! So why don’t I see any yet?…”
UPDATE (I guess) is “Innovation Nation – Solar Roadways” (1st story of 9min)
Thanks to MJS
Eclipse will cause a sudden drop and then a surge in solar-generated power
A partial solar eclipse on the morning of March 20 will be a good test of Germany’s electricity grid, which relies increasingly on renewable energy.
Will next week’s partial solar eclipse turn off the lights in Germany?
Experts say the country’s electricity grid, which relies increasingly on renewable energy, faces a crucial test on the morning of March 20, when the moon will pass in front of the sun and block up to 82 per cent of its light across Germany.
This partial eclipse will cause a sudden drop and then a surge in solar-generated power that will have to be balanced out to avoid instability in the grid, Germany’s Fraunhofer Institute for Solar Energy Systems said Friday.
Scientists at the Freiburg-based institute ran simulations showing that conventional power plants and hydroelectricity pump-storage facilities should be able to cushion the impact of the eclipse.
They found that the strain on the grid would be greatest on a sunny day — such as March 20, 2014 — when the drop and subsequent rebound would be strongest. Grid operators have likened the effect to 12 large power plants being switched off and 19 being switched on in a short space of time.
Impact expected to be negligible
If the weather is overcast, the impact should be negligible, the Fraunhofer institute found.
Solar power from some 1.4 million installations contributed almost six per cent to Germany’s energy mix last year, but is set to rise steadily as Europe’s biggest economy strives to meet 80 per cent of its energy needs from renewable sources by 2050. Germany currently gets almost 26 per cent of its electricity from renewables, including solar, wind, biomass and hydroelectric plants.
The upcoming eclipse will help grid operators plan for the next comparable event in 2026, when Germany expects to have shuttered its nuclear power stations.
Superstitions have surrounded the eerie solar eclipse since time immemorial. And now, for entirely scientific reasons, it turns out we have good reason to fear them. Earth’s biggest solar eclipse since 1999 is happening this March, and it could cause some real disruption—thanks to Europe’s reliance on solar energy.
Of course, Europe’s ready adoption of renewable energy is generally a good thing. But the major downside of solar energy is always going to be that we cannot control when the sun shines and when it does not. Most obviously, the sun sets everyday. And the weather changes. Less gradual and less predictable, though, is a solar eclipse. Here is how the European Network of Transmission System Operators for Electricity describes what could happen:
Under a clear morning sky on 20 March 2015, some 35,000 MW of solar energy, which is the equivalent of nearly 80 medium size conventional generation units, will gradually fade from Europe’s electrical system before being gradually re-injected: all in the space of two hours while Europeans and their offices begin a normal working week day.
I like to say that the grid is a lot like a lazy river at a water park. It’s not a line, it’s a loop: power plants connected to customers and back to power plants again. And like the lazy river, it has to operate within certain parameters. The electricity has to move at a constant speed (an analogy for what the engineers call frequency) and it has to flow at a constant depth (analogous to voltage). In order to maintain that constant speed and constant depth, you have to also maintain an almost perfect balance between supply and demand … everywhere, at all times. So when one generator goes out, the electricity it was supplying has to come from someplace else. Like a stream flowing into a new channel, the load will shift from one group of transmission lines to another.
The good news is that Europe has had a long time to prepare for the eclipse and anticipate how to shift the load. But this is the first time its power grid will be under such strain from a solar eclipse, so “the risk of incident cannot be completely ruled out.” Until we find good ways of storing excess solar energy in dark times—which, by the way, is a problem Elon Musk has now jumped on—solar eclipses will always be a headache for grid operators. Let’s just hope it doesn’t become one for the rest of us. [Financial Times, ENTSO-E, Discover Magazine]
NEW DELHI, Feb. 16 (UPI) — Construction is underway for a 750-megawatt solar power plant in India that is set to become the largest solar power plant in the world.
It will overtake the current production record set by the “Desert Sunlight” solar project in California, which produces 550 megawatts.
The project in India will cost about $640 million and will be constructed on about 3,700 acres of land in the Rewa district of the Indian state of Madhya Pradesh. The expected cost of power production will be about 8 cents per unit., the lowest in the country.
“The plant will be developed in three segments of 250 MW each,” additional chief secretary for new and renewable energy, SR Mohanty said to the Times of India. “Land acquisition will be over by end of month and over 90% land for the project is owned by government.”
The power plant is planned to be inaugurated on Aug. 15, 2016, India’s independence day.
India plans to have a capacity of 100 gigawatts of solar power by 2022.
Elon Musk’s electricity empire could mean a new type of power grid
A Binghamton University engineering researcher designed a biological solar cell that’s a million times more effective than current technology. Preliminary data on Seokheun “Sean” Choi’s next advancement is a thousand times better than that. His cell also works in the dark, and is self-sustaining.
The new designs don’t make biological solar cells practical, yet. But they do take them out of the realm of “absurd” and place them squarely in the realm of “someday soon.”
Here’s the challenge:
Current photovoltaic cells generate watts of energy per square centimeter. A solar chip about the size of your fingernail can power a simple handheld calculator. Existing biological cells—which use photosynthesis to generate electricity—produce picowatts per square centimeter—a trillionth of a watt. To power that same calculator, the cells would stretch 20 meters wide and from Binghamton to Ireland. Absurd.
Choi’s first biological solar cell produces a million times more energy, microwatts per square centimeter, so the calculator could operate with a solar panel that fits on a trailer home roof—just 20 meters by 5 meters. His findings were recently published in the Royal Society of Chemistry’s journal Lab on a Chip.
And Choi’s latest experiment churns out milliwatts per square centimeter—reducing the calculator’s solar panel to a backpack-sized 8 inches by 20.
That brings it into the range of practical application, says Hongseok “Moses” Noh, an engineer and professor at Drexel University who specializes in lab-on-a-chip technology and applications. “Milliwatt power should be sufficient to meet those eneeds,” Noh says. “But the device, so far, is too big for hand-held systems, honestly.”
If Choi can reduce the cell to a tenth of its size while maintaining milliwatt power density, it would be enough to power hand-held blood analysis devices or air-testing machines. “This is one of very few miniaturized bio-solar products,” Noh says, and it’s worth following Choi’s progress.
What makes Choi’s approach different? Existing biological solar cells use a thin strip of gold or indium tin oxide as an anode between the bacteria and an air cathode. Not very efficient, and the bacteria eventually die because they lack air.
Choi uses a carbon anode immersed in the bacteria-laden fluid—a pretty peridot green in a lab flask. More efficient, and because the solution has access to air, it’s self-sustaining. It also uses the plant’s natural respiration to draw energy from the sugars in the cells to keep power up even if light is low.
Choi, an assistant professor of electrical and computer engineering, says he doesn’t understand why one form of cyanobacteria works better than another, or why a mixture of cyanobacteria and heterotrophic bacteria work even better than a single variety. His last biology class was in high school.
“I have no idea about microbiology; I just bought the bacteria and followed the instructions to culture it,” he says. But millions of bacteria species abound, and he plans to experiment to find the most productive combination.
Or, he suggests, he might work with bioengineers to develop a bacteria with its photosynthetic engine on the cell’s surface instead of deep in its heart. That would be another order of magnitude more productive because less energy would be wasted just going from the heart of the cell to its exterior. He has received seed funding from Binghamton’s Transdisciplinary Area of Excellence in smart energy to continue this work.
Choi says he’s confident he’ll eventually reach watt-level energy density, comparable to photovoltaic cells. “I can get that,” he says. “We have room for improvement.”