Thick pipes run away beneath me like arteries, pumping oil out to the mirror field. There, it is channelled into thinner piping that runs right through the focal points of the mirror troughs, absorbing the heat of the Arizona sun until the oil reaches nearly 400 ?C. It then returns to the plant, where the oil superheats water vapour that spins two 140-megawatt turbines.

Six enormous white tanks surround the platform. Filled with molten salt, they can store enough heat to keep those turbines spinning at full capacity for 6 hours. The oil from the mirror field unloads its heat into the salt when the generators are at capacity. These tanks are what make Solana truly useful, not just producing carbon-free energy for
Arizona, but storing it for use whenever the grid operator needs it.

----------
A concentrated solar power (CSP) plant like Solana can play the baseload role because, unlike solar cells, it produces energy in the form of heat. Heat can be stored far more efficiently than electricity, as it does not need to be converted to other forms.

"The attractive thing about thermal storage, particularly with CSP, is that the round-trip efficiency is very high," says Charles Barnhart, a physicist at the Global Climate and Energy Project at Stanford University in California.

---------------
More plants like Solana are due to come online in the next year or so. In California's Mojave desert, Abengoa, the company which built and runs Solana, is constructing an even larger plant. Globally, CSP capacity is set to roughly double over the next three years as more plants come on stream, and a further 10 gigawatts of CSP has been announced worldwide.

For now, Solana is one of the few of its kind. Albert says its flexibility has already proved invaluable. "In the wintertime when it's cold, we have a morning peak in demand at 6 to 7 am, an hour or two before the sun comes up. We'll ask Solana to store energy overnight and start up a couple of hours before sunrise. How cool is that?"

FormulaNova said..

It sounds like you could even use it to smooth out conventional solar cells, and use the combination of the two.

Hopefully its economical and makes it here.

Beaglebuddy said..

Unfortunately these things incinerate birds, the disintegrate in a puff of flames when they pass thru and... they are even attracted to them, it is thought the mirrors look like water

Beaglebuddy said..

Unfortunately these things incinerate birds, the disintegrate in a puff of flames when they pass thru and... they are even attracted to them, it is thought the mirrors look like water

Beaglebuddy said..

Unfortunately these things incinerate birds, the disintegrate in a puff of flames when they pass thru and... they are even attracted to them, it is thought the mirrors look like water

Harrow said..


Can you give a link to a reference for the economics?

About 400 of these would be enough to supply all of AUS. I wonder what they cost to build and operate?

TheWolf said..





It is economical, but has a low ROI
There was a group trying to get a pilot station installed in SA. It was completely planned and costed and ready to begin construcion.
Instead a gas powered facility that had a larger ROI was given preference

Harrow said..




Wouldn't the infrared rays pass through the air until it hit an object. Either the block of salt, or some unfortunate bird. And I'm not sure I'd want to be circling the area in a glider!

Harrow said..




Over the short distance that the sun rays pass from the mirrors to the tower, the air would absorb a lot less heat than would otherwise have been absorbed if the sun rays were allowed to hit the ground. Without the solar tower, the sun rays would heat up the ground, which would then generate warm air and associated lift, but with the solar tower the sun rays are reflected to heat up the salt, and the heat would be stored, instead of released to the local atmosphere. The amount of heat generated by the rays travelling the short distance to the mirrors in the tower would be orders of magnitude less than the heat that would have been generated if the rays were left to hit the dirt. So the actual effect of the solar tower would be a considerable reduction in thermal lift in the area, with the energy being sent away as electricity.

We could of course number the mirrors surrounding the tower as such: 1, 2, 4, 5, 6, 7....997, 998, 999, 1000, and let the maintenance staff spend all their time looking for the missing mirror.

More importantly, when are you going to bring some more pies for sampling? Some warm tucker after a cool autumn southerly session would be just the ticket!

Test pilot 1 said..

I wonder how many rooftop sized units are made. Would be better for storing energy for night time use.
Having felt the heat reflected from solar panels, you'd think that you could combine the 2 principles using pv plated reflectors for dual production of energies(electricity/heat storage). Even if only for power and hot water you could run the heat collection pipes ont the back of PV panels, cooler panels would surely lower electrical resistance if only slightly and surely be a more efficient use of space on a roof.