Saving Solar Energy in the Dark

From The Oil Drum, see what you think:

Storing Energy Using Graphite:

The Canberra Times recently published an article, rather misleadingly entitled "Generating solar energy in the dark", which looked at the use of purified graphite for thermal energy storage.

The company developing the technology is called Lloyd Energy Systems, and they are prototyping solar energy storage, a wind-to-heat plant and a small-scale plant that combines water treatment, energy storage and steam turbine generation.

The company has received a $5 million Federal Government grant as part of its advanced energy storage technology program in the western NSW town of Lake Cargelligo, with Country Energy agreeing to purchase the power generated. Lloyd Energy also has an agreement with Ergon Energy in Queensland to build a $30million plant at Cloncurry in Queensland, partially funded by the Queensland state government, which the Sydney Morning Herald reported on last year.

[Lloyd Energy CEO] Mr Hollis said large amounts of coal-fired energy were lost during long transmission to remote areas. As power loads built up over time, mainly because of demand for air-conditioners, the grid could no longer cope in peak periods. Towns at the end of the line suffered the most from power shortages.

"We're putting environmentally friendly generation out at the end of the branches of the tree if you like, so it can pump energy back in when the branches are in trouble," he said. "It actually serves three purposes. Firstly, it is a renewable energy replacement for coal. Secondly, it avoids the country energy authorities having to upgrade their transmission lines so they can get more power out in the peak." The third benefit was having an energy source at the end of the line that could return power into the grid.

Sixteen full-scale models would go to Lake Cargelligo and 54 to Cloncurry. The system's mobility and flexibility had caught the attention of key Australian mining companies, which use diesel and gas generators.

Mr Hollis said making renewable energy available when it was required added to the system's value. ... "You can store thermal energy in a lot of things, but high-purity graphite is an extremely efficient way of storing it it doesn't have any losses. You can move the heat in and out very quickly."

Graphite based storage does not seem to have been used anywhere else in the world thus far. Storage for renewable energy has usually been limited to compressing air underground (Compress Air Energy Storage or CAES), where it can later be released under pressure, or pumped hydro, where the power is used to pump water back up into dams that can generate hydro-electricity. While both techniques are effective, they require suitable locations and complex infrastructure to be put in place.

The Queensland project will make Cloncurry the first town in Australia to rely exclusively on solar power, produced by a concentrated solar power (CSP) system. The system contains almost 7200 mirrors, which will guide the sun's rays into holes in the bottoms of 54 elevated graphite cubes, heating them to 1800 degrees (C). The stored heat is then used to generate steam for turbines on demand. The company claims the turbine will use less water than falls in an average year on the power station's roof.

Wind to Heat on King Island

A third system using the graphite system is being planned by CBD Energy, which has licensed the Lloyd technology and will build a wind-powered version of the system on King Island. The island, in the Bass Strait north-west of Tasmania, currently relies primarily on diesel to generate power for its 1800 residents.

The joint venture with Hydro Tasmania is not expected to make the island wholly powered by renewable energy, but it will eliminate the need for 1.25 megalitres of diesel fuel a year, says CBD's chief engineer, John Giannasca.

CBD plans to install two megawatts of wind turbines to supplement existing systems along with six graphite blocks. The blocks are each the size of a standard shipping container, and will be heated to 800 degrees (C).

Some solar panels will be also be installed for periods when the island is without wind, and there are ongoing investigations into harnessing ocean current and tidal energy in the region.

CBD Energy is run by ex-Impulse Airlines chief Gerry McGowan, with the company partly owned by German clean energy company Solon. CBD is also looking to develop solar energy projects in Australia, with plans for the first operation to be set up in the northern NSW town of Moree.

Graphite energy storage in context

King Island received a lot of press attention for an earlier project to store energy using Vanadium Redox flow batteries that began in 2003.

The company involved in that initiative, Pinnacle VRB, has since changed name to Cougar Energy and doesn't seem to have any active VRB projects going.

Another Australian company developing a slightly different form of Vanadium based batteries (Vanadium Bromide) is VFuel, though there hasn't been much news from them in some time either. Both VFuel and Pinnacle/Cougar are using technology pioneered at the University of NSW.

What will happen to the flow battery installation isn't clear, though a visiting parliamentarian (pdf) reported in 2004 that "The vanadium batteries would appear to best suit the ironing out of the wind fluctuations rather than holding larger quantities of power. The battery is expensive and takes up considerable space" and that graphite was being considered as an alternative.  (continue reading)

Go read some of their other articles here.

There are many questions I wish someone would ask the candidates.  They all keep saying they will "make America energy independent", but just HOW do they plan to TRY and do this?  No answer there, but their rhetoric is being eaten up by their followers.

Other reading:
McCain is Tonic for Post-Bush Republicans, American Power Blog
Al-Qaeda Uses American Web Host to Offer Palestinians Help, YID with LID

Will Sanctions and the Mughniyah Killing Make Syria Blink?
Syria Comment
Biggest "work accident" in years kills Islamic Jihad family , Elder of Ziyon
Algerian Culture Minister lauds Iran's services to Islam, Jihad Watch'
'I don't hate Muslims. I hate Islam,' says Wilders, Islamophobia Watch
Islam and the cross, from Christ The Truth
For the Record: Hesham Islam's Friend in Low Places, Muslims Against Sharia
Anti-Islam Crusader Popular in Holland, Right on the Right

Comments

[Rastaman]

That's a great article and you ask the right question, which is what are the candidates plans or are they spouting hot air. Most likely none of them really has any in-depth knowledge of eco-friendly energy production.

I have one question with that article, where it says the graphite system "has no losses". This doesn't compute. I assume the reason for using purified graphite is that it's been found to store energy efficiently, but after heating it to 1800 degrees, it won't just sit there. It will start losing heat. Of course it will have losses. Nothing holds heat indefinitely.

I can see where, on a commercial basis, that would be a far better system than the photovoltaic panel/battery storage system. The panels last a great many years but not the batteries. Outside of keeping the mirrors clean this system probably requires little maintenance.

Anything that gets us off oil is good.

Rasta

[Layla]

You said it Debbie - rhetoric. It is ashame but I am sure not much will be done in this arena.

The environmentalists will not allow us to do the right things to take this in the direction that would produce results.

They are all full of lofty ideas and rhetoric double speak.