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The fallacy of charging electric vehicles via solar panels feeding into a battery storage array then into an EV

Every single stage of energy transformation incurs a roughly 10 percent loss (mostly as heat). And right at the start, solar panels themselves are only 20 pct efficient so 80 percent of incident light in optimal conditions is automatically 'wasted' as heat by the panels themselves.

Lets break it down and this will show what a scam EV's and the Cults of Net Zero and Electric Jesus really are...

- It is only legit if you only use solar energy collected with panels on your own property and stored energy from those solar panels kept as chemical energy in your own home battery system that you convert back to electricity to supply to the car which then re-converts it back to stored chemical energy.

- Each energy transformation step incurs a roughly 10 percent energy loss (primarily as heat). If you charge an electric vehicle at all from the grid you are purely virtue-signalling as Net Zero is the ultimate green-washing scam and you have become a Cult member. So solar take light energy, changes it to electricity, which then changes to chemical energy.

- That's two stages of energy loss. The reverse process to charge any EV from a battery system is another two stages of energy loss. So out of the quantity of electricity output from the solar panels you lose 10 percent at each step.

- So 100 pct becomes 90, which becomes 81 (panels to batteries). For the second stage (batteries to EV) you start with 81 pct, which drops to 73 pct, then finally into the EV battery itself you only get 64 pct of the energy originally collected from the solar panels. Then when you actually drive the EV, you have two more loss stages - battery to electricity, and electricity to mechanical work. So you start at 64 pct, lose 10 pct down to 58 pct, then convert to mechanical work incurring another 10 pct loss down to 53 pct.

- So at the end of the process, of the 100 percent of energy output by the solar cells, only half of that ever gets turned into mechanical work by driving the vehicle.

- So The 'efficiency' of the full 'envelope' of solar panels to batteries to EV is very poor.

- Also do not forget that solar panels themselves are only 20 pct efficient, so of the light they collect, 80 percent is wasted as heat that the silicon cell structure cannot transform to electricity. So before you even start worrying about batteries your starting point is only 20 pct of the light energy that the panels get.

- This means that of all the light energy your fantastic solar panels collected, 53 percent of that is just over 10 percent. So the total energy envelope from solar panels to mechanical work from driving the car is only about 10 percent efficient! Net Zero my arse - it's a complete scam.

None of this takes into account the economics of all the raw materials and infrastructure required *just* to make the solar equipment, batteries, and associated equipment. Almost all of that is made in China, which is ironically the country with arguably the cheapest electricity on the planet.
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ArishMell · 70-79, M
I don't see how you manage to decide it is a "scam", since a scam is fraud, a type of theft, and no-one is stealing anything from anyone.

Nor do I take at all seriously, mere propaganda words like "cult".

I don't take the phrase "Nett Zero" literally either, just another propaganda term favoured by people who barely know a Watt from a Joule. Yet that something can genuinely not be perfect is not a reason to dismiss the thing entirely.

I think the problem is that some people expect far more than is sensibly feasible, of a home solar-array system, even in such an insolated land as Australia. I don't know the typical daily kW/h output of such system but expecting it to re-charge a large EV and power the home, seems a bit of a stretch.


Nevertheless it is fair to question of the efficiency of using a domestic solar-array system to charge an EV - and that will depend far more than whether you can simply plug any car into any such system, via a suitable converter of course). It depends very heavily on the individual vehicle, the daily mileage and driving style, and on the individual array and batteries - not alone but compared to that of the same motoring in an equivalent car powered by petrol or Diesel. (Where you buy the fuel, of course. Solar-power equipment is costly to install and has a finite life, but its "fuel" is free.)

You say only a fraction of the sunlight is converted to electricity. No system is ever 100% efficient, but are the photovoltaic cells unavoidably sensitive to only a narrow range of wavelengths from the Sun's wide spectrum from Infra-red (heat) to Ultraviolet?


Fair too, to include in the calculations, comparing the overall costs and benefits of charging cars from the mains with those of a domestic PV array - including the capital and relative economy of that array.


Very fair too, to question the sources of the equipment, espcially since so much of the world has let itself become far too dependent on China.

And very important to question the overall environmental credentials of that equipment, compared to those of cars using petroleum-derivative fuels and of those fuels; whose days are numbered anyway - whether we like it or not.

Merely hurling slang at something because you don't like it, won't achieve anything.
ArishMell · 70-79, M
@zonavar68 Their passing will turn mike sour in the cows, stop hens laying.... The human body cannot withstand travelling at such speeds....

Those were among the criticisms in the 19C aimed at the new fangled railway train. It could soon carry people at well over 30mph, the speed of a horse at full gallop, so faster than anyone had been carried in the entire history of humanity.

While as for vaccination, the introduction of the first, that for smallpox ( by using live cowpox serum) elicited some very strange attacks indeed. Edward Jenner carries all the credit for it but it was actually an English aristocratic lady who brought the knowledge home from talking to women in Turkey, where the method was already known. I only wish I could remember her name!

Now new under the Sun, is there, when it comes to fears of new technical developments.....
swirlie · 31-35, F
@zonavar68
You're definitely in the wrong line of work if you're a tech guy who's not a 100% supporter of EV technology.

Fly by wire technology of itself is over 60 years old, which puts it right up there with analog presentation, which is round instruments, switches, dials and levers.

If you really want to call yourself a tech guy, you have to be willing to accept and then rapidly adapt to the new technology that's becoming commonplace around us, like EVs parked in the driveway and home solar power generating systems that are either independent of the grid or contribute to the grid.
zonavar68 · 56-60, M
@swirlie I've been a tech/electronics guy since I was a teenager in the 1980's. I'm a freight train driver (and former suburban electric train driver) for work since 1990 so I am intimately involved with both low tech, and high tech, diesel electric locomotives and other stuff associated with rail freight transport. EV's are not the great solution they are painted to be. They are 'a solution', not 'the solution'.
Ontheroad · M
As far as I know nobody has suggested we can reach Net Zero with just solar energy production... not currently and probably not ever, but that doesn't change the goal of Net Zero and the use the combined resources of solar and with wind, hydro, geothermal, green hydrogen, and other low‑carbon carriers, supported by storage and grid modernization. This mix could ensure reliability, scalability, and cost‑effectiveness while keeping emissions at or below zero.
Ontheroad · M
@ArishMell The point, or what is at issue at least for me, is two-fold. One, fossil fuels are helping destroy our environment and planet, plus they are a resource that is dwindling.

Two, given the above, it is stupid to not look forward and let science and engineering lead us to getting as close as we can to Net Zero.

Net Zero is a useful term in explaining the goal, one we may or may never reach, but is a worthwhile goal.

And yes, the materials necessary to generate, store and transfer power are finite, or at least not infinite and we need to recycle/reuse all we can and use what use efficiently.

Obstacles are not roadblocks, they are a an opportunity to overcome, to learn and to progress.
ArishMell · 70-79, M
@Ontheroad I agree - though it's a pity the aim is seen by its detractors as something to be taken literally as a means to undermine it.

The whole matter though has been shrouded in the effects of burning hydrocarbon fuels instead of expanding it to examine not only their replacements but also the future availability of natural resources generally.

Hence, no petroleum? So how do we make the preservatives, lubricants, insulants, etc., that the alternatives all need; and make them in good, practical, sustainable sufficiency?

Dwindling ore reserves against growing demand for metals - not only "rare earths" but also key, more common, ones like copper, aluminium and iron - this last being the world's most valuable metallic element? How is that to be addressed?

And with it, the matter of who may gain control of the shrinking resources.


We can re-use most metals, with some attrition - and we should ban wilful waste such as losing hundreds of thousands of tonnes of high-quality steel by scuttling huge ships as mere playgrounds for divers. A huge amount of many metals is wasted in trickles, by ignorance, as when householders throw scrap electronic and electrical items in the ordinary refuse.

Re-using glass requires huge quantities of heat to re-melt it.

Some of the thermoplastics are refineable to a point - the product is of fairly low quality but adequate for certain classes of work. A vast amount of plastics are wasted in purely meritricious items; but too many campaigners, who seem to know little about these materials anyway, loudly condemn plastics by attacking their good uses, such as food wrapping.

Wood and its products are salvageable to some extent. So are some oils: including a flourishing trade in refining spent cooking-oil into compression-ignition engine fuel.

All those other chemical products made from petroleum and coal derivatives, are once-only, and once used, are never recoverable. What will replace them?

Scrap ceramics and cement products require vast amounts of heat in manufacture, but the finished objects, once scrapped, are good only for crushing to aggregate.



The scientists and engineers will do their best, and are indeed working hard on these, but we seem to hear or read little public realisation of it.

And little realisation that once a natural source material has gone, it's gone. Notwithstanding glib talk about mining the Moon or Mars.
Ontheroad · M
@ArishMell We have to explore the possibilities, think, learn and let science and engineering in their widely diverse fields, lead the way for us.

We have to think of tomorrow, of what comes next, and if we don't, our children somewhere down the line will pay the cost.
Munumbis · 46-50, M
The factor missing from your argument is that the original source of the power, the sun, shines totally for free. And Big Batteries now generate enough power in Western Australia to be regarded as a mainstream part of the generation grid, with a cost last measured as 70c per kinowatt and falling..😷
@zonavar68 Now you are starting to sound like a fossil fuel advocate.😷
zonavar68 · 56-60, M
@whowasthatmaskedman Not at all - but electrification of everything isn't the ultimate solution to human energy and transport needs.
@zonavar68 On that we find common ground. But it will be a part of the solution, for part of the problem. And it is a viable "next step" 😷

 
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