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We're going to need a lot of solar panels

caseyhandmer.wordpress.com

831–840 of 842 posts

Re: We're going to need a lot of solar panels

#831

Earlier quoted context omitted.

I see. The Green movement is globally all powerful, and you explain away the fact that the world is still not a Green utopia by saying the Green movement isn't actually Green. This is awesome mental gymnastics! The alternate explanation is that nuclear is a sick technology, and the Green movement is not responsible for its failure. Nuclear was so weak even a group as feckless as the Greens could have success against…

Greenpeace etc have long protested against nuclear, and have boogeymanned their way into the public consciousness on this topic. It's conceivably set us back decades and released millions of extra tons of CO2 in the process.

They have done sone damage, but you cannot lay the entire problem at their feet.

Do you think lobby from fossil fuel companies just sat on their hands all this time?

Re: We're going to need a lot of solar panels

#832

Earlier quoted context omitted.

I see. The Green movement is globally all powerful, and you explain away the fact that the world is still not a Green utopia by saying the Green movement isn't actually Green. This is awesome mental gymnastics! The alternate explanation is that nuclear is a sick technology, and the Green movement is not responsible for its failure. Nuclear was so weak even a group as feckless as the Greens could have success against…

Greenpeace etc have long protested against nuclear, and have boogeymanned their way into the public consciousness on this topic. It's conceivably set us back decades and released millions of extra tons of CO2 in the process.

A classic correlation/causation confusion. Yes, Greenpeace complained about fission. No, that doesn't mean they caused fission's failure.

If there's many billions of dollars in value to be created, that will trump anything a NGO can whine about. That's why we're still burning so much fossil fuel. Nuclear was vulnerable because it wasn't creating value.

Re: We're going to need a lot of solar panels

#833

Earlier quoted context omitted.

I think with 30kWp you should be able to heat enough sand to make it over the winter. It's a matter of space and finding someone to build you that heat storage.

Currently, it is cheaper though to "sell" the electricity in summer and "buy" it back in winter (even if it is at 10x the price I sold it for). Compared to private long term storage solutions. Most long term electricity storage solutions will yield electricity at prices above 80c/kWh here (even lithium ion is currently around 50 to 70c, if you calculate 10,000 hrs average lifetime of house batteries). And you cannot…

Sand is heat storage, not electricity storage. Storing heat can be much simpler and much more economical (considering that heat is the majority of your energy consumption).

Re: We're going to need a lot of solar panels

#834
post #402

Earlier quoted context omitted.

A clear majority of utility storage will not be batteries, just because cheaper methods will be favored. The cheapest will rely on E = Fx, where F is air pressure, or gravity, or buoyancy. But liquified anhydrous ammonia, despite being more costly to make, will be extremely popular because it is easy to transport and store, and is fantastically useful for many purposes.

I think that depends on battery tech. If they get magnesium air or metal free organic flow working I would imagine it would probably be chosen over mechanical methods. Ideally I suspect you don't really want utility storage anyway, you want something so cheap, small, and renewable you can do point of load storage and have a bit of grid independence, and not need as much transmission infrastructure.

Point of use storage costs a lot more.

Re: We're going to need a lot of solar panels

#835
post #809
post #728

Earlier quoted context omitted.

If you do the math, you'll see that your worries are misplaced. Because you already would have done it if you knew how, I've done it for you below. I do think that plastering the world with solar panels would be a real problem, and the logic of living systems suggests that it's a problem we'll have to contend with at some point. There's nothing that inherently limits human energy usage to anything like current human…

Thank you, this is a fantastic write up. One more question, if you don't mind - how many toxic materials do these panels contain? From what I've read, a typical landfill is designed to be leaktight for a couple centuries at most. After that, whatever heavy metals and other toxins were in the panels can start leaking into the ground and groundwater. It would suck to leave a bunch of poison drips for the future generat…

I'm glad you enjoyed it!

Basically silicon PV panels (the kind universally used now) are significantly less toxic than table salt and basically nearly else in your house.

The PV cells themselves contain silicon, aluminum, silver, and trace amounts of phosphorus and boron, and now sometimes gallium. Upon exposure to air or water the silicon surface passivates by forming a layer of amorphous silicon dioxide, which protects the silicon from further corrosion even in strong acids and room-temperature strong bases. Amorphous silicon dioxide is also used as an inert filler in pills, an abrasive in toothpaste, and one of the two main ingredients in simethicone, a treatment for gas pains. If you ground up the PV cells finely enough you could add them to your food with no ill effects.

Most of the mass of the panel is glass, which is also mostly amorphous silicon dioxide with small amounts of calcium and sodium oxides. This you could also add to your food in powder form with no ill effects, contrary to urban legends about ground-glass poisoning.

Gluing the PV cells to the glass is normally EVA, poly(ethylene-vinyl acetate). This is the material crafting hot-glue sticks is made from, as well as flip-flops, mouthguards, yoga mats, and those soft foam toys for kids. Less well known is that it's used as an extended-release drug delivery vehicle in implants: the drug slowly leaches out of the plastic inside your body, while the plastic remains unchanged. It has no known adverse effect on human health.

Sealing the back of the modules is a thin layer of, typically, polyvinyl fluoride (tedlar), which is also relatively biologically inert, but not to the same extreme as the rest of the materials. It's commonly used for raincoats and whiteboards. Hydrofluorocarbons tend to be of relatively low toxicity, but it's not thoroughly biocompatible in the same way as its cousin PVDF, or as EVA and silicon. Some panels are instead made with polypropylene or polyethylene terephthalate, which are as extremely nontoxic as the other materials.

The cells' electrical connections are soldered together with solder. Traditionally this was lead and tin, which does leach lead, though very slowly. Nowadays lead-free solder is used, typically consisting of tin and silver. This is another thing you can eat freely, although there might be traces of flux left from soldering.

The frames are normally made of aluminum, which is extremely nontoxic.

So, no heavy metals except tin and silver, which are nontoxic. Except that silver is toxic to bacteria.

There have been some experiments with nickel/copper plating to reduce the amount of (costly) silver used; I'm not sure if these are in production. Although nickel and copper are pretty safe, they're not nearly as astoundingly nontoxic as the other materials listed above. If you eat chunks of copper you will get sick.

Some thin-film panels have been made with more toxic materials like cadmium, selenium, copper, and tellurium, but they have mostly been driven out of the market by silicon PV cells. The total amount of these materials was small, but it's been found that they could leach out in an acid landfill. But they're not present in silicon cells.

So basically everything you have in your house is way more toxic than solar panels. Latex paint? Toxic polymers. Steel knife? Potential for iron poisoning. Concrete? There's substantial trace levels of many heavy metals in the cement, and it's basic enough to burn your skin, plus there are probably superplasticizer additives that are more toxic than anything listed above. Books? Likely still have trace levels of dioxin from bleaching the paper, plus most of the color inks are more toxic than anything in a solar panel. Polyurethane dishwashing sponge? Polyurethane is definitely not a thing you should eat. Foam cushions in furniture? In addition to polyurethane those contain halogenated fire retardants that are suspected of causing mass endocrine disruption. Wood cutting board? Most woods contain natural biocides to keep from rotting. Coca-Cola? Not only is the fatal dose of phosphoric acid relatively small, and it's keeping you from absorbing calcium, but also lots of the flavoring compounds are enormously more toxic than silicon and glass. Sand? That's crystalline silica, which causes silicosis and lung cancer if inhaled, unlike the amorphous silica we're talking about above. Stainless steel? Nickel can sensitize you over time and cause serious inflammation.

The only things I can think of in a regular person's house that are probably less toxic than solar panels are air, water, plaster, clay, glass, and aluminum cans.

Re: We're going to need a lot of solar panels

#836

Earlier quoted context omitted.

You're concentrating 4 wall's worth of condensation onto just one wall. Instead of being spread out, all the moisture gets on the one wall.

No, that is not how condensation works, otherwise you would have automatically more condensation on the wall in a larger room. The amount of condensation on the walls is not dependent on the size of the room or the fact that it condensates on the other walls. It depends on air humidity, air temperature, wall temperature and finally, very important, wall humidity. Water will not keep on accumulating on the wall, it wi…

The point is it won't reach an equilibrium. The outside of the house changes temperature with the day night cycle. The one uninsulated wall will be closer to the outside temperature than the other walls.

As the house cools at the end of the day the uninsulated wall will be colder than the other walls and if it's below the dew point condensation will form on it. If the temperature differential is high enough in comparison to difference in insulation between the walls then enough water will leave the air to keep the dew point below the temperature of the insulated walls and so that one wall will collect the majority of moisture (at 30C a meter cubed of saturated air carries about 30mls of water so yes condensation on a surface can heavily impact humidity). Once a wall becomes moist it will still acumulate water if it's below the dew point.

You likely will have seen real life examples of this when you look at single pane windows in otherwise insulated houses and seen them fog up/ have condensate form on them while the walls around them remain dry (if you haven't seen this but have been to houses with single pane glass in your area then condensation won't be an issue where you live).

As to your 75% efficiency point it will in fact have a lower efficiency as heat transfer increases with temperature differential. Since the room has a higher temperature differential with the outside the less insulated wall will be faster at transfering heat.

That is not to say that insulating 3 walls is a bad idea, it will almost certainly improve a rooms U value, but the worse the insulation on the remaining original wall, ceiling, and floor the less difference the 3 walls will make to the rooms U value and thus how quickly the room transfers heat.

Re: We're going to need a lot of solar panels

#837
post #571

Earlier quoted context omitted.

Why would you store it, instead of mixing it back in the sea? I guess you would need some pipes and pumps to move it away from your inlets, but that seems comparatively cheap.

because shoving all that brine back into the sea in the general area of the desalination plant causes a localized ecological disaster and dead zone of marine life

As said, use some pipes and pumps to move it away. Don't forget to dilute (again, use pipes and pumps or whatever you prefer).

Re: We're going to need a lot of solar panels

#838
To get a sense of how many solar panels and batteries we'll need, drive around Houston, Texas some time. You'll see mile after mile of chemical refineries. Granted, some of these are for plastics and not energy production. But a lot ARE for energy production -- and it's crazy to imagine how many square miles of solar and battery factories we'll need to provide an equivalent amount of energy production.

Re: We're going to need a lot of solar panels

#839

could someone explain the benefit of storing energy as natural gas? once you burn it, doesn't it result in co2? doesn't that defeat the effort? also is natural gas really easier to pipe around than electricity? I know I'm missing the point of the article so looking for helpful guidance.

Do you want to burn new carbon that’s in the ground, or recycle what’s already in the air? We have tremendous infrastructure already dedicated to using natural gas (cooking, heating, transport, industrial equipment) and it won’t be electrified overnight. First get to carbon neutral, then worry about carbon negative.

Thanks for making it crisp. This argument was in the article, but somehow it wasn't popping at me.

Re: We're going to need a lot of solar panels

#840
post #627

Earlier quoted context omitted.

Other places get much more heat, which is not good for solar.

On the contrary, it's far better suited to providing demand when solar is most available. It's far better than trying to fight the cold using solar. The tiny theoretical efficiency boost from lower temperatures and high sun is virtually irrelevant in comparison (and much more relevant to thermal power plant considerations). Much of the world gets literally twice the sunlight as most of Germany and that's the annual a…

Much of the world lacks what Germany (and Europe in general) has: industry. You can supply industry using solar, because it is needed during the day mostly. Yes, the output in winter is 10x smaller, that's why we need also other power sources (at least until we have a way to store electricity effectively).

What's the purpose of solar farm in Sahara? Lack of a need for electricity (except AC, but not many there can afford it) and transferring power over long distances is not effective.

For home heating there are other energy sources, not as clean (well maybe except wind, which blows during winter also): coal, gas, oil and nuclear.

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