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13 June 2014 Last updated at 19:24 ET
Vanadium: The metal that may soon be powering your neighbourhood
By Laurence Knight BBC World Service
Hawaii has a problem, one that the whole world is likely to face in the next 10 years. And the solution could be a metal that you've probably never heard of - vanadium.
Hawaii's problem is too much sunshine - or rather, too much solar power feeding into its electricity grid.
Generating electricity in the remote US state has always been painful. With no fossil fuel deposits of its own, it has to get oil and coal shipped half-way across the Pacific.
That makes electricity in Hawaii very, very expensive - more than three times the US average - and it is the reason why 10% and counting of the islands' residents have decided to stick solar panels on their roof.
The problem is that all this new sun-powered electricity is coming at the wrong place and at the wrong time of day.
Hawaii's electricity monopoly, Heco, fears parts of the grid could become dangerously swamped by a glut of mid-day power, and so last year it began refusing to hook up the newly-purchased panels of residents in some areas.
And it isn't just Hawaii.
"California's got a major problem," says Bill Radvak, the Canadian head of American Vanadium, America's only vanadium mining company.
"The amount of solar that's coming on-stream is just truly remarkable, but it all hits the system between noon and 4pm."
That does not marry well with peak demand for electricity, which generally comes in the late afternoon and evening, when everyone travels home, turns on the lights, heating or air conditioning, boils the kettle, bungs dinner in the microwave, and so on.
What the Golden State needs is some way of storing the energy for a few hours every afternoon until it is needed.
*snip*
How does a Vanadium Redox Flow Battery work?
Consists of two giant tanks of different solutions of vanadium dissolved in sulphuric acid, separated by a membrane- The battery produces an electrical current as the fluids are pumped past electrodes on either side of the battery
- In one tank, the vanadium releases electrons, turning from yellow to blue
- In the other tank, the vanadium receives electrons, turning from green to violet
- The electrons pass around a circuit, generating a current, while at the same time a matching number of protons (hydrogen ions) pass across the membrane between the two solutions
*snip*
That challenge of balancing electricity supply and demand is set to get a whole lot more difficult as ever more solar and wind energy is added to the grid.
Solar panel emergency call box in Hawaii
Which brings us back to Hawaii.
Rooftop solar panels don't just produce electricity at the "wrong" time of day, they also produce it at a low voltage, which, according to the German renewable energy entrepreneur Alexander Voigt, means it is effectively trapped at the level of the local community.
"Our traditional electricity grid is built in a way that the energy flows from the high voltage to the low voltage, and not the other way round," he says.
That means the solar energy can only be shared among the few households - typically just a village or a town neighbourhood - that happen to share the same transformer station that plugs them into the high-voltage national grid.
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http://www.bbc.com/news/magazine-27829874
http://nextbigfuture.com/2014/06/van...d-balance.html
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Solar turns tables on Australia’s electricity markets
By Giles Parkinson on 16 June 2014
Australia’s electricity markets are forecast to experience more declines in consumption over the next three years, as homes and businesses conserve energy, use smarter appliances and turn increasingly to generating their own electricity.
The 2014 National Electricity Forecasting Report issued on Monday by the Australian Energy Market Operator has highlighted once again how all previous assumptions about electricity demand have been turned on their head in recent years.
As we reported on Friday, AEMO has been forced to revise down its forecast demand for 2013/14 for a second time, and it now expects demand from the National Electricity Market to continue falling for at least another three years.
AEMO notes that in the past five years, instead of surging demand, consumption from the grid has actually fallen by an average of 1.8 per cent a year from 2009–10 to 2013–14.
Ironically, this has been driven, it says, by surging network costs – which have risen in turn because of the $45 billion that was invested on the basis of high demand forecasts five years ago.
These rising costs, in turn, have encouraged consumers to conserve energy, turn to more energy efficient appliances, and look to rooftop solar to deflect their costs. Demand has also been reduced by declining industrial production.
The fall in demand, or at least the fall in demand from the grid (because many houses with solar PV are still consuming, just producting much of their own needs), is being used by incumbent generators and others with vested interests as an excuse to halt, or slow down, the pace of deployment of renewable energy in Australia.
Many fear their complaints are getting a favourable reception from a review panel led by a climate skeptic, and a government which has described wind farms as “offensive” and renewable energy as having “no place” in modern society.
However the AEMO figures are used for the promotion of commercial interests, they do reflect a fundamental change in the way electricity markets operate, and the way in which electricity will be generated and delivered in the future.
AEMO says the only increase in consumption is coming from the massive LNG projects in Queensland. The state owned generators have hailed the prospect of being able to burn more fossil fuels to allow more fossil fuels to be liquefied and exported.
Elsewhere, there is no need for any additional generation, AEMO says, in any state before the end of its forecast period, 2023/24. The incumbent generators argue that this means there is no justification to force renewables into the market. Those on the other side say it’s about time the oldest and polluting generators exited the market.
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http://reneweconomy.com.au/2014/sola...-markets-81352
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