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Solar panel waste may not be as bad as we thought

fastcompany.com

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Re: Solar panel waste may not be as bad as we thought

#51

Post by thrown_22 »

da768 wrote: post #31
thrown_22 wrote: post #22

Earlier quoted context omitted.

>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) No they don't. When you add the efficiency of the grid, the charging station, charging the battery and discharging the battery burning a lump of coal to power your Tesla has _no_ advantage over burning a bottl…

Of course, on the other side, there's never any pollution involved bringing fuel to the gas pump.

Or to bring coal to the power plant.

Re: Solar panel waste may not be as bad as we thought

#52

Post by ajuc »

tpxl wrote: post #20
ajuc wrote: post #14

Earlier quoted context omitted.

One of the reasons is that a lot of these downsides are overplayed, based on long-obsolete data or false altogether. For some examples: - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) - rare earth minerals are limited which means we can't have everybody driv…

> lithium is more common than lead on Earth Lithium isn't a rare earth mineral.

It was about cobalt before, now that batteries switched to LFP without cobalt the naysayers switched to complaining about lack of lithium :)

Re: Solar panel waste may not be as bad as we thought

#53

Post by thrown_22 »

Schroedingersat wrote: post #45
thrown_22 wrote: post #22

Earlier quoted context omitted.

>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) No they don't. When you add the efficiency of the grid, the charging station, charging the battery and discharging the battery burning a lump of coal to power your Tesla has _no_ advantage over burning a bottl…

You forgot to include the other liter of fuel spent extracting, refining, and shipping the first one. Hence 2x. Also coal has double the emissions of oil per kWh so on an energy basis it's 1/4th

Keep moving the goalposts bud.

OP made a blatantly false claim. She was wrong. That's it.

Re: Solar panel waste may not be as bad as we thought

#54

Post by Schroedingersat »

nautilius wrote: post #23
jeffbee wrote: post #2

"Experts once warned millions of tons of waste from solar panels was on the horizon" Eh, no expert ever warned that. It was always an overblown issue, taken up by bored members of the press with deadlines to meet and column-inches to fill with words, shadow-funded by oil interest astroturf campaigns.

Do you have some resources about recycling of panels? I understand the point of the article is it's no longer the pressing issue it was once considered (by some), but I am curious if it's now just a delayed problem, or if recycling is a solved problem? Thanks!

Industrial scale recycling is both extant and has been mandatory in many countries for close to a decade http://www.solarwaste.eu/

Re: Solar panel waste may not be as bad as we thought

#55

Post by hgomersall »

thrown_22 wrote: post #22
ajuc wrote: post #14

Earlier quoted context omitted.

One of the reasons is that a lot of these downsides are overplayed, based on long-obsolete data or false altogether. For some examples: - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) - rare earth minerals are limited which means we can't have everybody driv…

>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) No they don't. When you add the efficiency of the grid, the charging station, charging the battery and discharging the battery burning a lump of coal to power your Tesla has _no_ advantage over burning a bottl…

Let's consider the numbers... A decent modern combined cycle gas turbine can achieve 60% efficiency, so let's take 50% to be conservative. Transmission losses are generally better than 15%, so that leaves a combined efficiency of 42.5%. A pessimistic charge/discharge efficiency for lithium ion would be 80% and I'd expect the charger to be 90% efficient, which gives us a total (pessimistic) efficiency of 31%.

An internal combustion engine has an optimistic efficiency of about 30%.

So, even if we ignore all the losses in fuel distribution for ICE cars and ignore regenerative effects in electric cars and the ability to incrementally decarbonise the grid, electric still has a slight advantage.

Re: Solar panel waste may not be as bad as we thought

#56

Post by kwhitefoot »

ilyt wrote: post #28
ajuc wrote: post #14

Earlier quoted context omitted.

One of the reasons is that a lot of these downsides are overplayed, based on long-obsolete data or false altogether. For some examples: - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) - rare earth minerals are limited which means we can't have everybody driv…

> - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) So do hybrids. Burning fuel at power station isn't 2x as efficient as burning it in ICE engine; most of the savings come from not wasting power while braking

> So do hybrids

No they don't. All the energy in a hybrid comes from an internal combustion engine which is generally less than 40%. Hybrids help by running the the ICE only when it would be efficient to do so but they can't help in constant speed highway driving.

Re: Solar panel waste may not be as bad as we thought

#57

Post by aftbit »

haberman wrote: post #49
ilyt wrote: post #28

Earlier quoted context omitted.

> - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) So do hybrids. Burning fuel at power station isn't 2x as efficient as burning it in ICE engine; most of the savings come from not wasting power while braking

> most of the savings come from not wasting power while braking That doesn't check out for me. ICE engines are inefficient because much of the energy from the fuel is converted into heat rather than kinetic energy. Every ICE engine has a radiator whose sole purpose is to vent off waste heat from the engine. ICE engines don't even need a distinct heating element to keep the cabin warm, the waste heat from the engine i…

Look up the Carnot cycle and its efficiency. This is theorized to be the best possible efficiency for a heat engine. All heat engines work by rejecting a large fraction of their input heat to an output heat sink. I've heard efficiencies in the 30-50% range for big coal and nuclear plants, much lower for smaller plants.

Re: Solar panel waste may not be as bad as we thought

#58

Post by CarVac »

bityard wrote: post #38
ilyt wrote: post #28

Earlier quoted context omitted.

> - electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) So do hybrids. Burning fuel at power station isn't 2x as efficient as burning it in ICE engine; most of the savings come from not wasting power while braking

I love my Prius, but over my years of driving it my suspicion is that the regen braking contributes VERY little power to the battery, and I try to brake using regen as much as possible. I would guess that most Prius drivers (who drive the car like a normal car, which is even what Toyota says to do) get back a truly trivial amount of energy out of regen braking. It wouldn't surprise me if full EV regen braking is much…

It's optimal to coast if you can avoid regeneration, but if you must brake then you want as much of that to be regenerative as possible.

On both EVs and on hybrids.

EVs have more regenerative braking power and capacity though; my Prius fills up rapidly when descending a mountain.

Re: Solar panel waste may not be as bad as we thought

#59

Post by lazide »

thechao wrote: post #39
googlryas wrote: post #12

Earlier quoted context omitted.

Honestly, at this point in our hyperpartisan world, I expect monsterous FUD about pretty much anything. There was just a small scale war in my city about a proposal to slightly modify the way our library is funded. If that gets people riled up, then one can only imagine what multi trillion dollar industries can stir up.

That's probably just a yellow bike shed, though?

Near as I can tell, a lot of people are just mad.

Not about anything in particular, just mad.

So really it doesn’t matter, they’ll pick a fight over anything.

Re: Solar panel waste may not be as bad as we thought

#60

Post by Retric »

hgomersall wrote: post #55
thrown_22 wrote: post #22

Earlier quoted context omitted.

>- electric cars are still burning fossil fuels cause powerplants burn fossil fuels (yeah, but electric cars go ~2 times further on 1 liter of fuel even if all our power came from fossil fuels which it doesn't) No they don't. When you add the efficiency of the grid, the charging station, charging the battery and discharging the battery burning a lump of coal to power your Tesla has _no_ advantage over burning a bottl…

Let's consider the numbers... A decent modern combined cycle gas turbine can achieve 60% efficiency, so let's take 50% to be conservative. Transmission losses are generally better than 15%, so that leaves a combined efficiency of 42.5%. A pessimistic charge/discharge efficiency for lithium ion would be 80% and I'd expect the charger to be 90% efficient, which gives us a total (pessimistic) efficiency of 31%. An inter…

Those are incredibly pessimistic numbers for power plants and optimistic numbers for ICE. On average 5% of the electricity transmitted and distributed in the United States is wasted your other numbers are similarly inaccurate.

ICE engines are only ~30% efficient under optimal conditions, idling still consumes fuel and engines idle a lot in normal driving including coasting down a large hill, slowing down, stoplights etc. Similarly turning on and heavy acceleration etc is extremely inefficient. This is where the primary benefit comes for hybrid cars not regenerative breaking.

Also, comparing gasoline to electricity ignores all the energy required to make gasoline. Oil refineries both use serious amounts of energy and release massive quantities of CO2 directly.

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