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Semi-transparent solar panels allow concurrent production of crops and power

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Re: Semi-transparent solar panels allow concurrent production of crops and power

#111

Post by dTal »

khawkins wrote: post #21

Only people who spend most of their life in densely crowded cities could think that the planet has so little space that you'd need to grow crops underneath solar panels for efficiency's sake.

And only someone blind to the ecological damage that agriculture does would regard all that land as free to use by humans, without consequences.

Here [0] is a map of the world's remaining wilderness. Notice how it's nearly all desert, with the exception of the Amazon rainforest. And hey, guess what's happening to that?

We are short of space. And time.

[0] https://images.theconversation.com/files/256144/original/fil...

Re: Semi-transparent solar panels allow concurrent production of crops and power

#112

Post by BurningFrog »

Communitivity wrote: post #16

Not just crops and power. I know a guy whose startup is using transparent solar panels in Germany on eco-friendly buildings with grass on roofs, to get power and eco-cooling, as well as Oxygen production - at least that is how he explained it. The concept is called green-roofs. Unfortunately I don't remember his startup's name. A link with details about the concept, minus the use of transparent solar panels: https://…

The oxygen claim doesn't inspire confidence.

Plants don't produce any useful amount of oxygen, and real scientists know that.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#113

Post by Retric »

Nextgrid wrote: post #89
Retric wrote: post #19

Earlier quoted context omitted.

Rooftop photovoltaic is currently more expensive, less efficient, and surprisingly dangerous to install. Solar thermal designs actually benefit from being on rooftops. As to dust, economies of scale make a huge difference. It’s rarely worth it, but using a farm truck to spray water across miles of panels is much more efficient than tens of thousands of homeowners doing the same.

What dangers are we talking about? Do solar panels add extra danger compared to just normal roof maintenance work?

To be clear their not that dangerous, but we are still talking extra deaths and accidents. Mostly from increased amount of time people spend on residential roofs. Roofing is about 30 deaths per 100,000 full time workers which is about double the average rate for construction.

Currently instillation is the primary, but not only risk. You also get electrical accidents and in rare cases fires. Plus an increased tendency for people to go onto a roof to check them out and or clean them etc. And some extra roof maintenance due to leaks from improper installation etc.

Personally, I don’t think it’s a major deal at the individual level. However, I thik it should be considered in terms of public policy.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#114

Post by xxs »

newyankee wrote: post #6

I cannot imagine the revolution that solar power will produce if it can fall another 3-5x in the next 10 years. It is already at grid parity. Although my personal hope is for storage, inverters, controllers and other technologies to get cheaper. Especially longer term storage beyond 4 hours.

Instead of inverters, there should be a push for DC network.

Virtually all SMPS would be able to to work with DC (right now) and they won't even need active power factor correction either. Washing mashines with brushless DC motors, most ovens would be fine too. When I think almost everything that I have home, save for geothermal pump and three-phase appliances would be ok powered by DC(0). DC has its own issues: galvanic corrosion possibly being one, arcs too (no self-extinguish 50/60 times sec) but it has no issues with inductance, hence lower transport costs.

(0)Cheap LEDs with capacitor dropper or regulation by triacs are not compatible.

Re: Semi-transparent solar panels allow concurrent production of crops and power

#115

Post by manfredo »

imtringued wrote: post #105
manfredo wrote: post #20

Earlier quoted context omitted.

> Batteries are catching up. Are they? The US consumes 11.5TWh of electricity daily. It's estimated that it needs 3 weeks if storage to get to 100% carbon free [1]. By comparison global battery production in 2019 was 300GWh [2]. Even if you factor in the fact that the curve of battery production is rising, it'd take decades to fullfil just the US's storage demands with batteries. There are other storage options like…

This is getting tiring... No, nobody is insane enough to only use batteries. They are primarily used to load-shift by a few hours within a 24 hour window. This is mostly useful for PV because it has a very low window during which it generates energy. Longer term storage would simply involve power to gas infrastructure. Alternatively you can use natural gas as your storage mechanism until power to gas has been impleme…

Existing energy storage options other than batteries are either geographically limited, or not feasible. I explain the issues with natural gas storage in another comment: https://news.ycombinator.com/item?id=24253317 You can't just produce natural gas out of hydrogen and air, you need a source of carbon (and the fraction of a percent of the carbon in the atmosphere cannot feasibly be used).

Yes, solar and wind can mitigate fossil fuel use in the short term. But there is no feasible way to use them for the primary source of energy without massive amounts of storage. It provides an option to produce some carbon-free energy, but does not provide an option to go from "some" to "all". If we actually want to stop climate change, we need to go for "all". The link you posted does not refute this. The solution proposed in the article is to just use fossil fuel backup plants until a storage solution is found.

Germany and California are both already approaching the saturation point for daytime generation. And once you hit that point there's no way to keep going without massive amounts of storage to transfer the excess generation during peak hours to non-producing hours. Intermittent sources cheaply reduce carbon emissions in the short term, but offer no path to fully renewable energy without a miraculous advancement in energy storage. The paper you linked to doesn't refute this. The plan laid out amounts to, "keep burning fossil fuels and hope we eventually figure out energy storage". When the fate of the world is at stake do you want to bet on an unknown and unproven solution, or a solution that has successfully delivered the lion's share of a nation's power since the 1980s?

Re: Semi-transparent solar panels allow concurrent production of crops and power

#116

Post by quotemstr »

tehjoker wrote: post #98
quotemstr wrote: post #70

Besides: nuclear power plants take up very little space. I really can't seriously people pushing solar, wind, and so on while they eschew nuclear power (and increasingly hydropower too). Fake environmentalists: "We have an existential crisis! We must change our energy strategy to save humanity!" Engineers: "That's quite a problem. Here's a way to solve it. It's called fission. Here are some power plant designs." Fake…

There's not enough nuclear fuel in the world to power the world for more than a little bit (iirc 30 years). It can at best be used as a transition source or a supplemental source.

> There's not enough nuclear fuel in the world to power the world for more than a little bit

This claim is simply false. The argument in favor of this view involves a very narrow interpretation of proven reserves that excludes discovery. The argument you're making is the same as peak-oil-ism, and we all know how that turned out.

https://www.world-nuclear.org/information-library/nuclear-fu...

Re: Semi-transparent solar panels allow concurrent production of crops and power

#118

Post by philipkglass »

manfredo wrote: post #20
toomuchtodo wrote: post #8

Earlier quoted context omitted.

I think it’s unlikely you see any fossil generation in the mix in 10 years except in the most remote of locations (with no solar or wind potential). Wind and solar are already around 2 cents/kWh utility scale, and batteries are catching up. No fossil or nuclear generation can compete with that.

> Batteries are catching up. Are they? The US consumes 11.5TWh of electricity daily. It's estimated that it needs 3 weeks if storage to get to 100% carbon free [1]. By comparison global battery production in 2019 was 300GWh [2]. Even if you factor in the fact that the curve of battery production is rising, it'd take decades to fullfil just the US's storage demands with batteries. There are other storage options like…

The full paper from citation 1 is available here:

"Geophysical constraints on the reliability of solar and wind power in the United States"

https://escholarship.org/content/qt96315051/qt96315051.pdf

If you look at Figure 2, they model different combinations of overproduction, storage, and regional aggregation (interconnection). Overproduction helps significantly. At 50% (1.5x) overproduction, the United States can supply 75% of demand with no storage and little new interconnection. At 1.5x overproduction with 12 hours of storage, it can supply 95% of demand with even less interconnection.

If the AP1000 units under construction at Plant Vogtle do not go over budget any further, they will have cost $11.20 per watt to construct [1] -- $25 billion spread over 2234 MW of generating capacity. If they have a capacity factor of 93%, that's $12.04 per watt of annualized output.

Utility scale solar in the United States achieves an average capacity factor of 25% as of 2018 [2] and had a median construction cost of $1.60 per watt as of 2018 [3], with costs still falling. That's $6.40 per watt of annualized output, or $9.60 with 1.5x overproduction.

Wind costs are similar. Wind has higher up front construction costs but also higher capacity factors in favorable regions.

Once constructed, solar and wind also have lower operation and maintenance costs per MWh generated than nuclear plants do.

I was very enthusiastic about nuclear power from about 2000-2015. I still think that it's safe enough and far cleaner than fossil power. We shouldn't shut any operating reactors down prematurely. But large scale renewable projects have cut costs drastically since the turn of the millennium while new nuclear projects keep going late and over budget. The EPR and AP1000 reactors were supposed to be the standardized, affordable, predictable reactors that retired the nuclear industry's history of cost overruns and schedule blowouts. Instead they have become spectacular contemporary examples of those same old problems.

[1] "Vogtle Cost Upgrade Causes Rethinking of $25B Nuclear Plant’s Future" https://www.power-eng.com/2018/08/09/vogtle-cost-upgrade-cau...

[2] "Capacity Factors for Utility Scale Generators Primarily Using Non-Fossil Fuels" https://www.eia.gov/electricity/monthly/epm_table_grapher.ph...

[3] "Utility Scale Solar: Empirical Trends in Project Technology, Cost, Performance, and PPA Pricing in the United States - 2019 Edition" https://emp.lbl.gov/sites/default/files/lbnl_utility_scale_s...

Re: Semi-transparent solar panels allow concurrent production of crops and power

#119

Post by quotemstr »

codefreakxff wrote: post #79
quotemstr wrote: post #70

Besides: nuclear power plants take up very little space. I really can't seriously people pushing solar, wind, and so on while they eschew nuclear power (and increasingly hydropower too). Fake environmentalists: "We have an existential crisis! We must change our energy strategy to save humanity!" Engineers: "That's quite a problem. Here's a way to solve it. It's called fission. Here are some power plant designs." Fake…

The tone of your post (being simultaneously dismissive and insulting to those who have a different view than you) is very trollish. The problem many people have with nuclear power are things like accidents making areas uninhabitable, radiation making people sick, disposal of waste rods is difficult, some materials can be used to make weapons, and the cost to make a safe plant are staggering and leading to cancellatio…

New nuclear power plant designs [1] have many intrinsic safety features that largely obviate the old safety concerns that you mention. Anti-nuclear advocates conspicuously ignore these new designs, instead opposing a vision of the nuclear power system that hasn't been current since the 1960s. Argumentum ad Chernobylum just convinces me that the animus against nuclear power comes from aesthetic considerations and not a sober optimization of human welfare against ecological damage.

[1] https://en.wikipedia.org/wiki/Generation_IV_reactor

Re: Semi-transparent solar panels allow concurrent production of crops and power

#120

Post by samatman »

dTal wrote: post #111
khawkins wrote: post #21

Only people who spend most of their life in densely crowded cities could think that the planet has so little space that you'd need to grow crops underneath solar panels for efficiency's sake.

And only someone blind to the ecological damage that agriculture does would regard all that land as free to use by humans, without consequences. Here [0] is a map of the world's remaining wilderness. Notice how it's nearly all desert, with the exception of the Amazon rainforest. And hey, guess what's happening to that? We are short of space. And time. [0] https://images.theconversation.com/files/256144/original/fil..…

Granted that the desert is effectively ideal for solar panels, and less useful for agriculture.

An interesting application of this technology would be building solar arrays along the edge of advancing deserts, with shade-tolerant plants with the sort of root systems which have been shown to halt and reverse desertification.

It's easier to do good things (such as halting the inexorable spread of the Sahara) if the operation is revenue-positive. Even though this would be more labor and less energy than just putting up a panel farm and calling it a day, it's more of a return on investment than the big old zero you'd get from just planting to try and fix dunes.

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