Almost Plausible Solar Takeover Plan

[Tom.G]

Gotta note the solar thermal plant that Ore-Ida built in Eastern Oregon to fry french fry potatoes.

Will do... but a link would speed things up a bit, please?

 

[shjacks45]

At 1000W per meter squared solar irradiation, for 1 TW that is about a square 30 x 30 km each side if the collection was all in one concentrated localized area.
Of course, solar panels do not collect 1000W per square meter, so the land area required increases substantially. There might be some "not in my backyard" issues to overcome, just because. ( elimination of the sun shining on my spot of land ).
But the amount of land used presently for particular endeavors such as transportation road network, golf courses, mining, just to name a few, usually isn't an issue most people contemplate. But I still suspect location of the solar farms, or panel placements ( such as rooftop or roadway right of ways ) might spark some discussion.

DOT is building walls around the freeways for noise abatement. Dessert areas for solar could fish farm (uses less water than farming) beneath panels and wind. Flat desserts are windy. Places like Denmark use VAWTs on building roofs. Coastal cities like Seattle get daily onshore and offshore breezes. Stormy weather makes less small solar, however typical home (fixed, facing south, angled ~40 degrees) gets 60% sunny day power on Seattle's 260 overcast days a year. Main problems with solar are rapid output decline after solar cell installation and the cost and enviromental costs. Most power used in Seattle area is winter home heating, an inefficient way of using solar energy. Should be more like direct solar: solar water heaters. I have installed "small hydro"; small hydroelectric is being shut down by energy conglomerates as they concentrate their power. This as 15% of power plants (nuclear) will reach end-of-life in next 5 years. Many dams built in the 1930s-1950s will be silted in in 20 years. And how about that Yellowstone caldera. It blew up 100s of megatons worth in the past. Or we could cool it down using Geothermal wells. The heat energy in Yellowstones magma exceed the energy of US coal reserves. Instead of water/steam, direct infrared to electricity "solar cells" (Thermoelectric cells) could be used.
I grew up on an american farm with a windmill that made electricity and pumped our water. We could charge the batteries from the tractor if necessary, but never did. We lived in the Mohave desert and had near constant wind coming down the mountains.

 

[shjacks45]

Will do... but a link would speed things up a bit, please?

Heinz bought Ore-Ida but still using Solar
https://digital.library.unt.edu/ark:/67531/metadc1071603/

 

[Fisherman199]

I have yet read the article, but I do know this: The drawings are already submitted and ground is being broken for infrastructure to accommodate very large solar projects all over the southeast. Big things to take place in the next few years. I would also expect governmental forces to play ever more apparent roles in these projects now that Biden is president apparent.

 

[shjacks45]

This article:
Overbuilding solar at up to 4 times peak load yields a least cost all renewables grid.

I'm normally among those who think that renewable advocates lack realism when they advocate 100% wind+solar grid. This article is the first I've seen that comes close to being plausible. I do doubt the article's numbers for storage and for wind, but the basic idea of massively overbuilding solar is in the right direction.

The basic idea is this. Actual solar generation depends strongly on the season and the weather. But even on the worst case day (winter solstice, thick clouds, and heavy snowfall), solar panels produce a fraction of their rated power. If there is enough overcapacity, then even that fraction will be big enough to supply the demand on that day plus recharge the batteries for that night. No heroics, special tricks or cleverness are necessary. Simplicity and reliability are the keys to successful power.

The article says 400% overcapacity is enough. I say 800% for the sake of argument and to allow for contingencies like hurricanes and ice storms. That is roughly 8 Terrawatts for the USA. At $1/watt installed, that's $8 Terradollars investment we need for the generation part (plus ? for storage). That's nearly 40% of the pre-COVID USA GDP. Big numbers, but conceivable when spread over a number of years.

Side issues:
Terrestrial wind in some regions is subject to 2-4 consecutive weeks with winds <15 knots, so wind production would be nearly zero. That makes terrestrial wind overcapacity less attractive than solar overcapacity. Offshore wind is more dependable, and thus more attractive, but it is only close to the coastline by definition. This whole idea is much easier to visualize with solar.

Solar capacity could be distributed across the continent close to the load centers. Therefore, massive new investments in power transmission or distribution would not necessarily be needed with this change.

What to do with the massive solar overcapacity in summer? The article says "curtailment" meaning shut down portions so we don't generate energy that we can't use. But the excess capacity could be used to produce hydrogen or fresh water production by desalinization. Hydrogen and desalinization are not economical in most circumstances, but if the alternative is curtailment of excess capacity, we might reconsider their economy.

Others have proposed use rather than curtailment before, but they weren't thinking on the scale of 700% of peak demand. The economies of scale would be very significant.

The required overcapacity would be less in southern states than northern states. Fresh water is more scarce in southern states.

We already have the technology (called synthetic inertia) to make solar panels behave transiently like old fashioned steam turbine generators. That allows a non-disruptive transition with respect to grid operations and control. No matter what the ratio of solar to conventional generation, the dynamics of the grid would remain nearly constant.

Of course it would take lots of engineering to study the actual feasibility of this plan. Perhaps 50 engineering-man-years to do the study. If I was not retired, I would bid for the study contract myself I know exactly the team to do it. It is a study that I believe should be funded.

p.s. It's fun to have something other than COVID-19 to think about.

A CEO acquaintance invests in clean energy. His company has small and medium hydroelectric (waterfall bypass like Niagra), wind properties, geothermal, The idea of covering useless dessert land with solar cells fails to understand WHY the land isn't used. The US Southwest is geologically "basin and range" terrane, not flat like Midwest farmland. It's not too dry to farm, it's too rocky. You can actually see the windmills at the Tehachapi wind farm from space (or google satellite view). But a closer view of the Tehachapi mountains shows jagged hillsides not usable for much else. Coastal cities like Copenhagen have seen use of building-top VAWTs which complement Solar to generate in bad weather as well as good. Geothermal is overproducing for Iceland, the Yellowstone Caldera is over a mantle hot spot (like the Hawaiian Is.) So sucking all the energy out of it is unlikely. Urgent because current nuclear plants generate 15% of US power and reaching engineered end-of-life. Many US hydroelectric projects date back to 1930s and dams fill up with silt over time, currently provide 5% of US generation capacity. Of course coal still generates 40+ % of US electricity.

 

[Fisherman199]

I read the article and slept on it. I have many questions but the basic assumption is not wrong (which is not the same as being good and is further yet different form being correct). I still think the article borders on issues with accepting realism but the numbers check out. I think their assumption of 400% overbuilding seems very generous to me. I think 8 or 9 (even 10) times installed capacity would be needed. Current installed capacity is about 1.1 TW. An overbuilt PV/Wind system would be around 8.8 - 11 TW. Being very generous on the numbers it'd be about $1.30 US for each Watt on average. Total investment could range from $11.4 T US to $14.3 T US. That's 53% to 66% of last years GDP. These numbers are massive as will be price increases to customers. If the time-scale is anything less than a decade or two this plan would be madness to implement. That being said, I'd almost give money away to be a part of a study on this ideas feasibility.

 

[anorlunda]

When I wrote that article, the price for panels was about $0.80/watt. Panels only, installation not included. 2 weeks ago, I saw that the bulk price of panels has dropped to $0.12/watt, and the price for a whole solar farm installed, tested and connected to the grid is down to $0.75/watt, or $6 Trillion per 8 TW.

And the price declines don't stop here. Soon we will be at a point where the cost of mowing the weeds in a field once per year will be more than the cost of covering it in a solar farm. It is like Moore's Law on steroids.

So, as you probably know, a planning study projecting 10-20 years into the future would have to take those trends into account and use future prices lower than today's.

I also note that some people are concerned about land use. They fear that we need to cover vast land areas with panels. It is nowhere close to that. Here's a quick calculation.

Power density for one panel:	18 watts/square foot [194 w/m^2]
Square feet in one square mile:	27,878,400
MW per square mile	502 [194 MW/km^2]
Square miles in the lower 48 of the USA	3,119,884 [8080464 km^2]
Percent of the land needed for 8 TW.	0.5%

The ability to generate power locally rather than transmit it across continental distances is a major part of the appeal.

 

[jrmichler]

And there are many dual use opportunities to install solar panels to minimize the impact on land use.

The total area of interstate highways, state highways, and parking lots is about 40% of the needed land area in the @anorlunda calculations above. I like the idea of shade, especially when driving toward the sun. And the idea of shaded parking lots on hot sunny days.

Some farm crops apparently have better yields when partially shaded. Here's one link that has numerous other links in the article: https://www.treehugger.com/agrivoltaics-solar-power-crops-bees-4863595. They discuss crops that have better yields when partially shaded, reduced need for irrigation, and improved working conditions for farm workers. Arable land in the US is about 16.6% of the total land area: https://data.worldbank.org/indicator/AG.LND.ARBL.ZS?end=2016&locations=US&start=1961. Since only 0.5% of the total US land area would be needed for 100% solar, agrivoltaic has the potential of holding enough solar panels to fully meet US needs.

Rooftops could hold solar panels for over 1 TW: https://www.nrel.gov/docs/fy16osti/65298.pdf. Their estimate is based on 16% cell efficiency, so may be low. This would be more practical if solar panels were designed to be the roof, instead of being installed over the roof. Since roofing materials are not getting cheaper, and solar is getting cheaper every year, the possibility of a solar roof cheaper than a conventional roof exists.

 

[mfb]

And the price declines don't stop here. Soon we will be at a point where the cost of mowing the weeds in a field once per year will be more than the cost of covering it in a solar farm. It is like Moore's Law on steroids.

How much can installation costs drop? Installing something on something else isn't a particularly new technology, how much more can be saved?

 

[anorlunda]

How much can installation costs drop? Installing something on something else isn't a particularly new technology, how much more can be saved?

That's a good question. Certainly, the cost decrease exponent for the panels is not necessarily the same as the exponent for installation. But there is still a long way to go on the installation side.

I'm speaking mainly of solar farms installed on open land, rather than rooftops.

I watched a nearby project last summer of about 250K m²/ size. I saw that the start-to-finish time is short and the labor crews small. I estimate 5000-10000 m²/ installed per man-day of labor, so the labor costs were low. They used specialized machines.

The obvious future direction it to make installation machines like agricultural machines that plow/plant/harvest. The machine could roll over open land, leaving a finished installation behind. They drill holes, fill them with concrete, then push posts into the wet concrete, attach frames to the posts, and panels to the frames, and do whatever they need for the wiring. The frames hold everything rigid while the concrete hardens. Lasers and computers let them adjust for land contours. One pass and the job is done. That sounds to me like a level of difficulty comparable to some existing agricultural and road building machines.

In Lake County Florida (my winter home) they had a freeze in the 1980s that killed orange trees. Even today, there remains about 10⁹ m² of abandoned agricultural land in Lake County available for a new use.

 

[paradisePhysicist]

Like this, perhaps? For a sense of scale, see the cars in the parking lot at lower right.

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View attachment 272590
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That is Solar One in the Mojave Desert (California). It was retired in 1988. This is a Solar Thermal unit. The top of the tower, operating at 1000°F, has molten salt circulating in it as a thermal transfer fluid. Then water is boiled to drive a conventional steam turbine/generator system.

Photovoltaic cells are destroyed at those temperatures.

Solar Two and a bit more info at:
https://www.atlasobscura.com/places/solar-one-and-solar-two

Also:
https://climatekids.nasa.gov/concentrating-solar/
But they are V-E-R-Y slow to connect, it may take a few tries.

Cheers,
Tom

@paradisePhysicist: With PV this is generally known as concentrator PV. You save some PV area but you increase the complexity of the system, you generally need tracking to follow the Sun, you create heating issues, and it only helps with direct sunshine - on cloudy days your mirrors are not brighter than the sky they obstruct.

Hmm I see the issue, I am going to have to study ambient lighting a little bit more and get back to you.

However the design you mentioned is not my design, I will draw my design here.

basically the sun shoots a cone of light at earth. (Really the sun emits a sphere of light but only a cone of it hits earth.) With normal solar panels the only part of this cone you are getting is the surface area of the solar panels+ambient light. But with this invention you get more than 10x the amount of light you get normally.

The economics are changing so fast. I suspect that we are already at the point where the cost of one square meter of mirrors is about the same as one square meter of PV panels.

Three years ago, the price of panels (not including installation) was $1/watt. Now it is about $0.12.

Mirror-like materials can be cheap, we can use mylar foil as cheap mirrors instead of real and expensive mirrors.

For less than 1 dollar you can get 54x84 inches of material:
https://www.amazon.com/dp/B01M4GRQVJ/?tag=pfamazon01-20

 

[NTL2009]

... But with this invention you get more than 10x the amount of light you get normally. ...

Have you estimated or calculated how hot the surface of a solar panel will get with a 10x concentration of sunlight?

Have you studied the effect that temperature has on solar panel efficiency?

Do you know the maximum temperature a solar panel can withstand before it is damaged?

... Mirror-like materials can be cheap, we can use mylar foil as cheap mirrors instead of real and expensive mirrors.

Yes, but you need frames to hold them, and you need to protect them from wind, animals, etc. I don't think mylar film will stand up to much wind.

 

[Windadct]

The PV cell efficiency decreases with temperature - it looks like the maximum boost runs about 40% unless the PV is actively cooled.

The elevated temperature will probably not kill the PV outright, however all aging related effects are also accelerated at the higher temps.

There are some more novel PV technologies that would do better with the higher temps - but all of this is driving the price and complexity up.

This has been looked at from all angles.

 

[anorlunda]

@paradisePhysicist ,

It is a bit like Moore's Law with silicon semiconductors. There are always promising non-silicon competitors. But by the time they get perfected in performance and manufacturing, silicon improved so much that the competitors don't look so great after all.

PV performance, and manufacturing cost, and installation cost are all on exponential improvement curves. As I said in #100 of this thread, I expect to see robotic installation of solar farms analogous to agricultural crop handling.

 

[berkeman]

The PV cell efficiency decreases with temperature

Too funny, that phrase gave me vertigo and sent me down a mental rabbit hole for about 30 seconds wondering what I was missing. Then I realized that there was an implied word that was counterintuitive for me (after reading "decreases") -- The PV cell efficiency decreases with increasing temperature

Sometimes my mind gets stuck and tripped up when parsing stuff...

 

[BillTre]

Too funny, that phrase gave me vertigo and sent me down a mental rabbit hole for about 30 seconds wondering what I was missing. Then I realized that there was an implied word that was counterintuitive for me (after reading "decreases") -- The PV cell efficiency decreases with increasing temperature

Sometimes my mind gets stuck and tripped up when parsing stuff...

Been there, done that.

 

[dlgoff]

Sometimes my mind gets stuck and tripped up when parsing stuff...

Could this maybe be a result of an experiment you once mentioned? IIRC it had to do with galvanic skin response.

 

[paradisePhysicist]

Have you estimated or calculated how hot the surface of a solar panel will get with a 10x concentration of sunlight?

Have you studied the effect that temperature has on solar panel efficiency?

Do you know the maximum temperature a solar panel can withstand before it is damaged?

No but it seems important, I should probably look into that.
Just offering another avenue for the r&d to look into, I will appreciate getting a cut of the gains if this invention is ever developed, I understand the hardest part is probably making new PV's that operate well under heat.

Just thought it might be easier for R&D to focus on creating new panels that operate well under heat, instead of focusing development towards 100% effeciency panels.

Yes, but you need frames to hold them, and you need to protect them from wind, animals, etc. I don't think mylar film will stand up to much wind.

The prototype will be a polygonal design, since it will be difficult to print out curved rings. Instead it will be a ring comprised of flat planels with the mylar flatly glued onto the panels. The mylar needs to be as flat as possible so the mylar would have to be bought directly, before the creasing happens when it is folded into mylar blankets.

The PV cell efficiency decreases with temperature - it looks like the maximum boost runs about 40% unless the PV is actively cooled.

The elevated temperature will probably not kill the PV outright, however all aging related effects are also accelerated at the higher temps.

There are some more novel PV technologies that would do better with the higher temps - but all of this is driving the price and complexity up.

This has been looked at from all angles.

This is unfortunate. Also I had another idea concerning my solar invention, but I forgot what it was. I should have posted it sooner when it was on the tip of my tongue.

@paradisePhysicist ,

It is a bit like Moore's Law with silicon semiconductors. There are always promising non-silicon competitors. But by the time they get perfected in performance and manufacturing, silicon improved so much that the competitors don't look so great after all.

PV performance, and manufacturing cost, and installation cost are all on exponential improvement curves. As I said in #100 of this thread, I expect to see robotic installation of solar farms analogous to agricultural crop handling.

Cool. Here is some news about gold and silver semiconductors. Sounds expensive but could be the future:
https://www.advancedsciencenews.com...e-next-big-thing-in-semiconductor-technology/
https://www.nanowerk.com/nanotechnology-news2/newsid=55301.php
Moore's law no longer applies to computing
https://www.technologyreview.com/2020/02/24/905789/were-not-prepared-for-the-end-of-moores-law/
The CEO of Nvidia said this as well. Silicon has a huge head start but maybe eventually the gold and silver semiconductors will surpass the development speed.

 

[mfb]

Concentrator panels exist. They are being sold commercially and produce some of the electricity in some grids. People have tested various different geometries and kept the designs that work best. They still come with significant downsides.

If you want to propose a new model then you first should figure out why this was discarded before you assume it must be something revolutionary.