Arizona solar plant

[palladin9479]

http://en.wikipedia.org/wiki/Capacity_factor

CSP Solar in California = 33%

That's for Ivanpah, which according to this has no thermal storage capacity.

The same Wikipedia page mentions 75% CF for CSP solar with storage in Spain (15h storage capacity).

This plant in Arizona (6h storage capacity) is probably somewhere in between.

There is a caveat to CSP's. They are not more efficient then PV plants, their definition of nameplate capacity is changed. It's not physically possible for a solar plant to generate more then 50% CF, the sun isn't shining for 75% of the day. What they do instead is lower the nameplate capacity and thus generate a large number. The plant's cost remains the same, the energy produced remains the same, the only difference is the nameplate is 1/2 of what a PV plant would be. IE a 200MW CSP plant generates the same power as a 400MW PV plant but instead of releasing it all into the grid or into batteries it stores it as thermal energy to be released later. Remember energy storage has absolutely zero to do with Capacity Factor. Also all CSP's have thermal storage, it's a requirement of the design. The CA one doesn't have a dedicated long term high density thermal storage solution, their not playing games with nameplate capacity.

Seriously think for a second how could a terrestrial solar plant generate energy for longer then 50% of the day?

[paperburn1]

Seriously think for a second how could a terrestrial solar plant generate energy for longer then 50% of the day?

More likely worse than that, when calculating for my house the prime window is only 6 hours. Even tracking will only add two or three hours to that figure.
And your 100 percent correct, solar for my house is 10 times easier than for a commercial power plant.

[Teahive]

There is a caveat to CSP's. They are not more efficient then PV plants, their definition of nameplate capacity is changed. It's not physically possible for a solar plant to generate more then 50% CF, the sun isn't shining for 75% of the day. What they do instead is lower the nameplate capacity and thus generate a large number. The plant's cost remains the same, the energy produced remains the same, the only difference is the nameplate is 1/2 of what a PV plant would be. IE a 200MW CSP plant generates the same power as a 400MW PV plant but instead of releasing it all into the grid or into batteries it stores it as thermal energy to be released later.

The definition of nameplate capacity is not changed, it's still peak sustainable output. The plant can simply capture more solar energy at peak sunshine hours than its generators can convert into electricity, using heat storage to average input energy. Which, by the way, makes it a lot more useful than a 400MW PV plant without storage. The cost structure is also different.

Remember energy storage has absolutely zero to do with Capacity Factor.

No. Capacity factor has absolutely zero to do with input energy.

[palladin9479]

EIA disagree's with you td.

http://www.eia.gov/tools/faqs/faq.cfm?id=187&t=3

Capacity factor is a measure of how often an electric generator runs for a specific period of time. It compares how much electricity a generator actually produces with the maximum it could produce at continuous full power operation during the same period.

For example, if a 1 MW generator produced 5,000 MWh over a year, its capacity factor would be 0.57 because 5,000 MWh equals 57% of the amount of electricity the generator could have produced if it operated the entire year (8,760 hours) at full capacity and produced 8,760 MWh of electricity.

Generators with relatively low fuel costs are usually operated to supply baseload power, and typically have average annual capacity factors of 0.70 or more. Generators with lower capacity factors may indicate they are in operation during peak demand periods and/or have high fuel costs, or their operation depends on the availability of the energy source, such as hydro, solar, and wind energy.

CSP's play with the definition of CF by altering the measuring point. Nameplate is determined by the maximum power a plant can produce at once, a gas plant that's capable of generating 200MW of power operating at 100% is rated, and sold, as a 200MW plant. Same with coal, nuke, hydro, wind, geo and PV solar. All CSP's do is direct sunlight to a spots on a tower filled with a liquid with incredibly high thermal capacity. That liquid is then heated up and acts as a huge battery. When they need power they just run a water loop through heat exchangers and turn a turbine. Instead of using the theoretical maximum instantaneous power like everyone else they artificially restrict / underrate the power output to get a higher CF value. The 400MW PV plant would store it's power in battery's the exact same as the 200MW (actually less, more like 100~150MW) stores it's power in thermal fluid. Ultimately you get approximately the same total power out of both, one just looks better on paper. This sounds like a semantics game until you start looking at direct and opportunity costs and land usage. It puts CSP Solar into the same category as PV Solar and Wind, which is utterly horrible as a utility power plant (yet very useful for direct local usage).

[Stubby]

Evidently the 3 square mile solar plant builders are insensitive to the special environment that is being destroyed just so someone can wear a green ribbon on their chest. And it is especially precious because those brutal wheat and cattle ranchers would have left that land alone leaving the wild life free to roam. But that is normal for insensitive people to view habitats that are called barren as being unimportant.

Cute.
Using an standard environmental argument to argue against a renewable energy power plant.

[Teahive]

CSP's play with the definition of CF by altering the measuring point.

They don't. Your quote states very clearly that the measuring point is the electric generator.
This Arizona plant has two turbines rated at 140 MW for a total nameplate capacity of 280 MW. CF refers to that nameplate capacity. Whatever happens before steam hits the turbine does not matter for nameplate capacity or CF.

Installing generators which can't convert peak heat capture into electricity isn't some shady move to make the plant look better, it's a decision that makes economic sense.

The 400MW PV plant would store it's power in battery's the exact same as the 200MW (actually less, more like 100~150MW) stores it's power in thermal fluid. Ultimately you get approximately the same total power out of both, one just looks better on paper.

Since nameplate capacity is quoted much more often than CF it's the PV plant that looks better on paper. But nameplate capacity and capacity factor are just measured facts.

This sounds like a semantics game until you start looking at direct and opportunity costs and land usage. It puts CSP Solar into the same category as PV Solar and Wind, which is utterly horrible as a utility power plant (yet very useful for direct local usage).

Maybe. I'd be very interested in seeing the actual numbers (and even more importantly, improvement trends).