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Solar is winning the energy race

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Re: Solar is winning the energy race

#71

Post by snowchaser »

Jedd wrote: post #65
snowchaser wrote: post #40

Earlier quoted context omitted.

It’s a good question, but the reality is the energy required to power a car is far larger than what you can collect. The solar energy you can collect is about 750W/sq meter. A car roof is about 5’x5’, and if we are generous and include a trunk and hood area, maybe you are getting 60 sqft? Best case if the sun is right over the car you can illuminate about 5 square meters. That’s about 3.75KW. To convert that to a mor…

> The solar energy you can collect is about 750W/sq meter. > A car roof is about 5’x5’, and if we are generous and include a trunk and hood area, maybe you are getting 60 sqft? We must think metric, every inch of the way! Anyway, PVCs currently max out at about 300W / square metre - and that's in ideal conditions. I believe theoretical maximum energy per square metre (when light actually arrives at the planet surface…

Totally agree, SI units for the win!

I was just trying to use “familiar” units. I could have led with 1 HP per square yard, and then you’d totally have license to call me out!

And yeah, I was just talking about solar flux, there’s a whole lot of real world losses to consider but my point was that none of this matters, it’s orders of magnitude away from ICE engine output.

Re: Solar is winning the energy race

#72

Post by thechao »

embedding-shape wrote: post #59
defrost wrote: post #36

Earlier quoted context omitted.

You absolutely can .. but in order to be self sustaining vehicles need to look somewhat like the builds that appear in Australian multi day solar races - ultra lightweight, extreme streamlining, zero driver comfort, no extras like cargo space and automatic rear doors, etc. Maybe in time efficiencies will get there. * https://worldsolarchallenge.org/ * https://www.youtube.com/watch?v=4K0FD9Hh6XY * https://www.youtube.…

Ok, so lets say we didn't want 100% of the energy to come from those "self-sustainable panels on the car", but rather N%, so we keep most everything as-is, except switching all the outside body/chassi panels for solar panels, how much N% could we recover from that? Could it change so someone goes from needing to charge once every 3 days to once every 2 weeks lets say? Together with re-generative breaking, maybe it co…

You're off by an order of magnitude. It's a few hundred watts; an EV is consuming 10s of kilowatts. (Ignore the watt-watt/hour sloppiness, pls.) To charge my car 60% would take about 2 months. Ambient needs (battery cooling) would eat up more than I'd get back. At best it extends idle sit time.

Re: Solar is winning the energy race

#74

Post by patall »

healthy_throw wrote: post #44
mixermachine wrote: post #22

Earlier quoted context omitted.

Especially for hot and sunny areas solar is insane. At mid day, max heat, you get the peak production and can run your AC at full throttle. That enables you to efficiently work at nice temperatures.

Heat reduces solar production, ideally you have very sunny environment with about 25C / 77F.

Why is that always posted without stating the magnitude of the effect? The numbers that you find online are around 15% relative loss at 60°C vs. 25°C panel temperatur (I remember a HN comment reporting 12% comparing peak April to peak July). That is significant, but not world changing, especially for AC.

Re: Solar is winning the energy race

#75

Post by izacus »

cbmuser wrote: post #9
mmooss wrote: post #6

Earlier quoted context omitted.

Connect enough grids and the sun is always shining.

Yeah, just build a 300 GW transmission line from the US to Europe. It will basically costs nothing.

And it absolutely won't be used by MAGA and Putinist crazies as a tool of extortion.

Re: Solar is winning the energy race

#76

Post by don_esteban »

Moldoteck wrote: post #58
don_esteban wrote: post #41

Earlier quoted context omitted.

Another advantage of solar that it is decentralized and difficult/too costly to shut off by a country bombing you (Ukraine benefits from this) (unlike a big centralized power plant). I think the biggest potential is in the 3rd world countries for which hydrocarbon import is a big drain on their convertible monetary reserves (especially now with the rising oil prices). A farmer with enough free land and significant di…

full decentralization is not a feature but a bug imo - you spend a lot on transmission. Germany now spends 10x more than france on transmission and curtailment and has highest prices in EU. It's the best to have a hybrid - centralized pp and centralized solar/wind parks but distributed evenly across country. Ukraine had also massive loss of ren power because most solar+wind was in south (because of better weather) an…

You are looking at it from the point of view of 1st world country that has a functioning highly centralized generation and distribution system.

My view is more from the 3rd world country where the generation and distribution is insufficient and unreliable.

To goal is to have local generation closely tied to local production, greatly alleviating the need for global long-distance transmission. Yes, it does not work as well as well functioning global system, but that is not the reality of the 3rd world. And can be achieved much cheaper/simpler than a well-working global system.

Sort of like Africa leapfrogging land lines and going directly to cell phones.

Electric machinary does not have to be crazy expensive. As electric cars do not need to be crazy expensive, that is the market the west is willingly leaving to China/rest of the world. (Just go to China/Asia and see cheap electric cars. For locals, the electric is the cheapest option.)

Re: PV is already sufficiently cheap: For 1st world, and for the current applications. Bringing the battery costs down would enable much wider use of solar.

Last year I have been to remote parts of Indonesia. Almost all local transport was by small boats, with japanese ICE engines. The availability (logistics of getting the fuel to small remote islands) and cost of fuel were quite limiting. If each village/homestead had their PV farm for charging their boats, their life would be transformed.

Re: Solar is winning the energy race

#77

Post by ViewTrick1002 »

didgetmaster wrote: post #54

I am confused. The article claims that solar is the best, cheapest source of power. It also claims that the Trump administration is undermining it in the US by cutting federal subsidies. If solar truly is the cheapest, why does it need any help from any government? It would seem to me that it should flourish in any capitalist society where money naturally flows towards the cheapest solution that actually works.

Where at the point in the transition where the level of subsidies, if any, determines the speed of the build out.

The question is: how early do you retire existing thermal power plant?

Re: Solar is winning the energy race

#79

Post by nirolo »

kwakubiney wrote: post #31

Might be a noob question, but why can't EVs have solar panels on them directly so they can get charged just by moving around? Or why can't we have SVs(Solar Vehicles)? Why do we have to use solar panels on EV stations rather than just having them on the vehicles themselves?

Aptera has this planned but not sure if they ever reach market maturity.

There also was a project car from the Nordics I think. Can't recall the name though.

Main problem is the large amount of energy a car needs vs what kind of surface area you have and efficiency we get.

An ideal (100% effiwncy) solar cell of 5m² would still need 20 hours to charge a 100kWh battery. And we are way off on area an efficiency in reality.

Re: Solar is winning the energy race

#80

Post by sheikhnbake »

defrost wrote: post #63
didgetmaster wrote: post #54

I am confused. The article claims that solar is the best, cheapest source of power. It also claims that the Trump administration is undermining it in the US by cutting federal subsidies. If solar truly is the cheapest, why does it need any help from any government? It would seem to me that it should flourish in any capitalist society where money naturally flows towards the cheapest solution that actually works.

The USofA is a broligarchy not a capitalist society, so there's that. Trump has his thumb on the scales, cancelling wind farms in progress via executive order, not cancelling the federal subsidies for fossil fuels, etc. There are always transition overheads to breach - in China the government there subsidised the non existant EV industry into being, now that's going gang busters the government support has dropped bac…

Broligarchy is the natural end stage of unfettered capitalism. We've arguably never been more capitalist.
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