Ivanpah: Open for the Sun's Rays

[Jason]

The new Ivanpah Solar Electric Generating Station outside Primm, Nevada, opened for business last week. With an expected capacity of 370 megawatts - enough to power 140,000 homes according to an EarthTechling report - the plant's three mirror arrays. The massive array can generate around 370 megawatts at peak output and around 945,000 megawatt-hours per year. While these large scale projects play a very important role in developing solar as a utility-scale power source, they have benefits for people who want to set up their own home solar systems as well. All of these large plants enable technology to develop, making solar overall cheaper for all users, whether they are utilities or home- and business-owners. With solar becoming more efficient, that means individual homeowners can get more bang for their buck by going solar. It's very easy now for home solar plants to have a 3 megawatt capacity just from rooftop panels, and that's likely to improve even further.

More...

[J.P.M.]

The new Ivanpah Solar Electric Generating Station outside Primm, Nevada, opened for business last week. With an expected capacity of 370 megawatts - enough to power 140,000 homes according to an EarthTechling report - the plant's three mirror arrays. The massive array can generate around 370 megawatts at peak output and around 945,000 megawatt-hours per year. While these large scale projects play a very important role in developing solar as a utility-scale power source, they have benefits for people who want to set up their own home solar systems as well. All of these large plants enable technology to develop, making solar overall cheaper for all users, whether they are utilities or home- and business-owners. With solar becoming more efficient, that means individual homeowners can get more bang for their buck by going solar. It's very easy now for home solar plants to have a 3 megawatt capacity just from rooftop panels, and that's likely to improve even further.

More...

They probably won't have tours, but I'll check into it as I'll be by there sometime this spring for a peek.

[SunEagle]

They probably won't have tours, but I'll check into it as I'll be by there sometime this spring for a peek.

Don't forget to bring your sunglasses.

[J.P.M.]

Don't forget to bring your sunglasses.

Two sets, one polarized, worn at same time and a welder's hood from prior life. Been at this a while. Thanx for the advice.

[Sunking]

The massive array can generate around 370 megawatts at peak output and around 945,000 megawatt-hours per year.

That is all for that massive amount of money and space. I would not be bragging about it, rather than cover up the facts as it is embarrassing. A very small conventional plant the size of a 18 wheel truck can generate that much power in a day and cost 1/1000 of that price.

[Pablodro]

The massive array can generate around 370 megawatts at peak output and around 945,000 megawatt-hours per year.

There's something odd about these numbers. I know they are tracking at Ivanpah but 945 Gwh per year is the equivalent of achieving peak output 7 hours per day, 365 days per year. Either the annual number is wrong or they have gross overbuild in elements of the plant that allows them to achieve peak output in seriously non-optimal conditions.

[Sunking]

There's something odd about these numbers. I know they are tracking at Ivanpah but 945 Gwh per year is the equivalent of achieving peak output 7 hours per day, 365 days per year. Either the annual number is wrong or they have gross overbuild in elements of the plant that allows them to achieve peak output in seriously non-optimal conditions.

Hush you fool, no one wants to hear the truth and spoil the hype.

[J.P.M.]

There's something odd about these numbers. I know they are tracking at Ivanpah but 945 Gwh per year is the equivalent of achieving peak output 7 hours per day, 365 days per year. Either the annual number is wrong or they have gross overbuild in elements of the plant that allows them to achieve peak output in seriously non-optimal conditions.

It does seem high, but maybe not impossible. While not defending the #'s or the amount of real estate it takes up (but also, BTW, not seeing folks standing in line to buy the land either, except perhaps the golf course across the street.), or, for example, not particularly liking how the north end of the Coachella Valley looks with a couple thousand wind systems displacing about as much energy as a 1200 mWe centralized power plant for all of what some may consider visual blight:

1.) There are about ((24)*(365))/2 = 4360 hrs./yr. of daylight per yr. everywhere on the planet, more in summer, less in winter, except at the equator.
2.) I'm using an educated guess and saying that the area around the Ivanpah power generating facility has a yearly clearness index of something like .65 to .70 or so. I'll use .65 for now. The clearness index here being defined in the usual way - the ratio of solar irradiance on a horizontal plane at the earth's surface at some location to the solar irradiance on a surface of the same orientation "above" the earth's atmosphere, i.e. in outer space over some time period, in this case one year.
3.) If every day at Ivanpah was clear and clean that clearness index would be something like .73-.75 or maybe a bit less. I'll say .75 for now. That's about as high a yearly clearness index as you're likely to find anywhere and probably close to the theoretical limit.
4.) While not strictly accurate, the ratio of clearness index to the max. theoretical clearness index is not a bad 1st approximation of the ave.% of possible beam radiation at a location, better for desert locations such as this perhaps.
5.) If so : .65/.75 = .87 ~~= % annual of possible beam radiation. Say and use .85 for now with some seasonal variation that may make that # a bit more conservative yet.
6.) That might mean that for design purposes, an average yr. at Ivanpah might see something like (4360)*(.85) = 3706 hrs. of beam radiation/hr. = ~~ (3706/365) = 10.15, say and use 10.1 hrs. /average day, more in summer, less in winter based on solar geometry alone (roughly as some function similar to something like the sunrise/sunset azimuth angle).
7.) Figure another 5% loss for outages, mirror cleaning, etc. and knock it back to, say, 9.5 hrs/day.
8.) This REAL ROUGH, back of the envelope, but perhaps somewhat conservative estimate would suggest that if the average output of the plant is (7.0/9.5) ~~= 70-75% of max. stated output, it may well have a shot at achieving or approaching the stated yearly output.

FWIW.

[SunEagle]

Two sets, one polarized, worn at same time and a welder's hood from prior life. Been at this a while. Thanx for the advice.

No problem. Also watch out for all them tortoises that have been displaced from their habitat to install them mirrors. You never know when you might fall into one of their borrows.

Even if it takes up a lot of real estate and produces the amount of energy that a small Utility "peaker" can, it still looks pretty amazing in the Google Earth photo.

[russ]

945,000 mWh per year - say all good average weather

945,000/365 = 2589 mWh per day / 7 hours = 370 mW plant

The ratings on wind and solar throw in some flaky capacity factors that make it difficult to understand.

Like Sunking pointed out - it is a rather small plant - maybe the equivalvent of a 110 mW gas turbine.

[Sunking]

Like Sunking pointed out - it is a rather small plant - maybe the equivalvent of a 110 mW gas turbine.

Not only small, but power generation is unreliable and not available 24 x 7

[bcroe]

It's very easy now for home solar plants to have a 3 megawatt capacity just from
rooftop panels, and that's likely to improve even further.

Even I couldn't find room for that many panels, and 80% efficient panels aren't likely a near term
development. I suppose they mean 3 megawatt HOURS PER YEAR; sure get tired of the press
(with no sense of reality) throwing out bad numbers and bad units. Bruce Roe

[Sunking]

sure get tired of the press
(with no sense of reality) throwing out bad numbers and bad units. Bruce Roe

You when they do that ignorant citizens put NoBama in the WH