EEVblog 1480 - Lightyear Zero Solar Powered Electric Car - Page 1
Forum section: electronics / general

author: EEVblog
author_rank: Unknown
timestamp: June 20, 2022, 04:22:31 am
content: Are solar powered electric cars viable? Let's look at the Lightyear Zero solar powered electric car and examine the claims. Can you get a useless extended range by adding solar panels to an electric car?Dave just so happens to drive a solar powered electric car, so let's find out!

author: ataradov
author_rank: Super Contributor
timestamp: June 20, 2022, 04:50:23 am
content: Imagine maintenance cost on this. All the exposed surfaces on the car are made out of glass.Also, no rear view mirrors, so I assume they are relying on displays. This not not even legal in most places.

author: Bud
author_rank: Super Contributor
timestamp: June 20, 2022, 05:14:05 am
content: Might work somewhere in Saudi Arabia ...And what is the deal with the "vegan interior"

author: innis226
author_rank: Newbie
timestamp: June 20, 2022, 12:36:34 pm
content: How do these guys get funding? Don't Venture Capatalists have technical people of their own telling them this is just wankery?

author: jonovid
author_rank: Super Contributor
timestamp: June 21, 2022, 08:45:57 pm
content: to be viable IMOany solar powered electric Car needs to be like 1900 classic antique car design with a big1kw flattop solar roofover an open-air cab with motorbike spoked type wheels.with a top speed of only 80kmh. a metropolitan shopping car/ cart , you park outdoors as it has its own carport for a roof. also the solar roof can be a type of roll cageand windscreen support with a gap at the top for better aerodynamics. higher performance then any golf cart. ABS disc brakes , anti-roll bars. low center of gravity floor.

author: thm_w
author_rank: Super Contributor
timestamp: June 21, 2022, 10:00:52 pm
content: https://www.eevblog.com/forum/dodgy-technology/lightyear-one-solar-car/Quote from: ataradov on June 20, 2022, 04:50:23 amThe sides are not glass right? I don't see how maintenance is worse unless you smash the glass.Expensive cars are expensive to repair already, don't think the owner of a 250k car cares much.

author: Marco
author_rank: Super Contributor
timestamp: June 21, 2022, 10:25:02 pm
content: Wind shields are supplied by a competitive industry.I've changed my mind, I don't think the solar roof is a bad idea in and of itself. If you like the aesthetics. Getting one without a long running contract guaranteeing low cost availability of replacement roof glass is a bad idea though.

author: bdunham7
author_rank: Super Contributor
timestamp: June 21, 2022, 10:26:50 pm
content: Quote from: innis226 on June 20, 2022, 12:36:34 pmYou think VCs don't intentionally fund wankery?

author: Marco
author_rank: Super Contributor
timestamp: June 21, 2022, 10:34:41 pm
content: Quote from: Bud on June 20, 2022, 05:14:05 amThey don't want to say imitation leather.

author: McBryce
author_rank: Super Contributor
timestamp: June 24, 2022, 10:00:18 am
content: Quote from: EEVblog on June 20, 2022, 04:22:31 amHi Dave,take a look at Sono Motorshttps://sonomotors.com/too when you get a chance. Their claims and figures are equally questionable and to top it all they have solar panels on the sides too!McBryce.

author: wraper
author_rank: Unknown
timestamp: June 24, 2022, 10:12:32 am
content: Quote from: Bud on June 20, 2022, 05:14:05 amVirtue signaling for those "concerned" about cattle being butchered. And who do not bother to figure out that no cattle are butchered for leather, as it's just a mostly unwanted byproduct of meat processing. More of which goes to waste as cheaper "Vegan leather" becomes more prevalent.

author: Marco
author_rank: Super Contributor
timestamp: June 24, 2022, 03:28:03 pm
content: The leather still sells, just for cheaper. Reducing the profits of animal agriculture byproducts increases the price of beef, decreases consumption. Perfectly internally consistent with vegan aims.

author: wraper
author_rank: Unknown
timestamp: June 24, 2022, 03:51:20 pm
content: Quote from: Marco on June 24, 2022, 03:28:03 pmThese days butchers usually give it away for almost free or completely free because otherwise they need to pay for disposal. Almost all of the cost comes from processing, not cowhide itself. All of this vegan garbage results in discarding perfectly good natural material which is biodegradable and instead selling oil derived garbage which usually is way less lasting and at the same time not biodegradable. The result is filling landfills with a lot of garbage which will not decompose for many centuries. Go green, yay!

author: Marco
author_rank: Super Contributor
timestamp: June 24, 2022, 05:26:16 pm
content: Quote from: wraper on June 24, 2022, 03:51:20 pmWhat old timey butchers do is neither here nor there. The meat and potato are the meat processing plants, dealing with butchers is just too much work for mass production of anything. Whether it be the cream of the crop for leather, or the rest for gelatin. Which the vegans also don't eat, ever so slightly running down the price and ever so slightly the ROI of rearing cattle. Then there's rendering, biogas fermentation, composting. It doesn't go to waste, it just goes to minimal profit.Regardless, vegans aren't the cause there's too much cowhide to make into leather ... the cause is that we eat so much beef.

author: thm_w
author_rank: Super Contributor
timestamp: June 24, 2022, 09:00:05 pm
content: That and vegan leather does not need to be made from oil, it can be made from a number of sources. Hell they even state "Vegan interior with naturally sourced materials".Of course, doesn't mean its any good as a material.https://www.greenmatters.com/p/vegan-leather-made-from-plants

author: Bud
author_rank: Super Contributor
timestamp: June 25, 2022, 12:23:35 am
content: I wonder how many cows would need to be sucrificed to make interior of this car, were it non-vegan. Perhaps not many.

author: coppice
author_rank: Super Contributor
timestamp: June 25, 2022, 12:35:07 am
content: Quote from: Bud on June 20, 2022, 05:14:05 amMost of the stuff called vegan leather seems to be the kinds of low end plastic materials we've been finding passing for leather in furniture for years, that starts to flake and crumble quite quickly. There's quite a lot of real leather furniture where only the main face of a seat is real leather, and they use some garbage for the side pieces, that flakes after 5 years. Watch out for Ikea office chairs.

author: JPortici
author_rank: Super Contributor
timestamp: June 25, 2022, 06:07:11 am
content: Quote from: ataradov on June 20, 2022, 04:50:23 amHad to work on a maserati MC20. Rear camera and high resolution display shaped as the rear view mirror. I could litterally not tell until i turned to look and saw that the rear window was all cluttered by the engine. probably charging 5k for that system alone, but it was seamless. probably better quality than any screen i saw in my life and nothing, i repeat NOTHING like any screen you have ever seen in a car

author: ataradov
author_rank: Super Contributor
timestamp: June 25, 2022, 06:29:40 am
content: Quote from: JPortici on June 25, 2022, 06:07:11 amSure, but the laws are not created for $5k systems, they are created for typical junk you will see on the roads. And that's why it is illegal in many places. It looks like it is legal in Europe, which is nice I guess.But a very common concern that I've seen with cameras and displays that you don't see in static tests is the amount of time it takes to refocus your eyes. With a real mirror this process is instantaneous, but with the camera and display you are not looking though the optics and your eyes need to refocus on the display and then back on the road. This causes fatigue. I have not tried, so I can't tell how real this issue is.And it is just more unnecessary shit that can break, of course.And small aperture of the camera can get dirty much easier. If you drive in a place where there is snow and dirt, you are screwed. But in that case you are screwed with a solar car anyway.

author: wraper
author_rank: Unknown
timestamp: June 25, 2022, 07:32:35 am
content: Quote from: Marco on June 24, 2022, 05:26:16 pmI didn't mean butcher as individual. Call it a slaughterhouse, whatever. English is not my native language.QuoteIt's people who want to be "responsible", or want to be on the right side of public opinion, therefore buy synthetic junk. It does not stop them eating meat though.

author: golden_labels
author_rank: Super Contributor
timestamp: June 25, 2022, 08:39:15 am
content: Do you need to visit a car wash before each travel, so the cells’ output was not limited by dust?To people concerned about rear mirrors: a lot of cars do not have those, because there is a solid wall behind the seats or are packed with cargo in normal use. I do not know about legal status of that all around the world, but this is common enough to be somehow addressed in the regulations. Relying on a display is not an issue for a car where literally everything relies on electronics. A display can also deliver much better experience. I’m using a panoramic rear mirror myself and all I can tell about the standard rear mirrors mounted in cars is: from that perspective they seem like useless gimmick.

author: tszaboo
author_rank: Super Contributor
timestamp: June 25, 2022, 10:04:13 am
content: Quote from: coppice on June 25, 2022, 12:35:07 amI'm like 90% sure there is a combined industry push to produce interiors to cars that basically decompose after 5 years of usage. Look at all the black piano shiny plastics that gets scratched up at daily usage, and collects dust. They are using intentionally obsolete tech in the dashboard, which already looks outdated now, imagine it in 5-10 years. The low quality imitation leather fits into this perfectly.Nobody would want to buy a 5 YO used car after it looks like a chewed up dog toy on the inside.And this is still better than the turbochargers that blows up at 5 year 1 day, like clockwork.

author: cortex_m0
author_rank: Regular Contributor
timestamp: June 26, 2022, 03:56:41 pm
content: The solar car is actually more viable than I would have guessed.The $26,000 starting price for the Aptera would make it the cheapest EV on the market in the USA, and even the upgrade from the base 250 mi battery to the 600 mi battery would still keep it in the top 5 cheapest category.Perhaps the market niche it fills best is the person who lives in an apartment and has no means of plugging in a BEV at their apartment complex. Public chargers are pricey (relative to at-home charging). A car that could generate 20 to 40 miles of range per day would extend the interval between public charger sessions, potentially significantly.

author: SiliconWizard
author_rank: Super Contributor
timestamp: June 26, 2022, 07:30:12 pm
content: Quote from: ataradov on June 20, 2022, 04:50:23 amYep. A ridiculous amount of extra energy, huge maintenance (not even talking about repair!) costs, and the average price of a Lamborghini. What's not to like?

author: nctnico
author_rank: Super Contributor
timestamp: June 27, 2022, 12:06:33 am
content: Quote from: ataradov on June 20, 2022, 04:50:23 amWhat maintenance costs? The windows on my cars typically last the lifetime of a car unless somebody breaks one. Also many modern cars have large glass areas (like the roof and rear hood) because glass is relatively cheap while offering a lot of structural integrity (on most modern cars the windshield is giving the car a lot of structural integrity).IMHO whether putting solar panels on a car is a good idea depends on the ROI. If the solar panel pays for itself in saved electricity / fuel costs (hybrid) then I'd say go for it.

author: Bud
author_rank: Super Contributor
timestamp: June 27, 2022, 02:30:44 am
content: I'd be more concerned about crash safety. Zillion of glass pieces coming at you , thank you very much....

author: golden_labels
author_rank: Super Contributor
timestamp: June 27, 2022, 03:12:00 am
content: Quote from: Bud on June 27, 2022, 02:30:44 amThere is a thing called laminated glass. Used in cars for quite some time.

author: Bud
author_rank: Super Contributor
timestamp: June 27, 2022, 05:51:20 am
content: Is it used in solar panels though?

author: ataradov
author_rank: Super Contributor
timestamp: June 27, 2022, 05:55:12 am
content: Given that they are form fitted, I assume you could order them in whatever configuration you want.My concern was not so much with constant damage, but more with one off events when you get hit by a rock from the ahead or something like this. Even with plain glass it is annoying. But I guess if you have money for $250K car, you are not worried about such things.

author: McBryce
author_rank: Super Contributor
timestamp: June 27, 2022, 11:02:32 am
content: If you removed all the additional weight that the panels / DC/DC Converter and extra cabling create you would probably increase the range by the same amount that the panels claim to give you.McBryce.

author: coppice
author_rank: Super Contributor
timestamp: June 27, 2022, 01:07:35 pm
content: Quote from: golden_labels on June 27, 2022, 03:12:00 amWhile laminated glass exists, works really well, and is pretty stable over a long lifetime, it is rarely used for anything but windscreens in cars, because of cost. Only a very few makers use laminated glass for their panoramic roof panels, for example - basically only the ones with a long term image for safety, like Volvo. On the other hand, most of the glass panels in cars are not as dangerous as a typical window breaking, as they are made from tempered glass - nasty, but not usually lethal.

author: SiliconWizard
author_rank: Super Contributor
timestamp: June 27, 2022, 06:42:43 pm
content: Quote from: ataradov on June 27, 2022, 05:55:12 amThis is a ridiculous amount of money for such a car.$250k cars are usually the luxury/sports car that have and keep a very high value for decades. They are not just cars, but a safe investment. This? Who really thinks it will even sell at 1/4 of its price 5 years later? That is, if the company still even exists?

author: nctnico
author_rank: Super Contributor
timestamp: June 27, 2022, 11:16:43 pm
content: Quote from: SiliconWizard on June 27, 2022, 06:42:43 pmPeople also buy $250k hand bags so...

author: cortex_m0
author_rank: Regular Contributor
timestamp: June 28, 2022, 11:55:48 pm
content: One of the automotive YouTube channels got a brief test drive of a Lightyear Zero prototype in Spain. It seems like the solar does generate meaningful power, and it continues to generate while in motion. On a perfect sunny day the solar wouldn't do much to extend a road trip, but even so the Lightyear Zero, per their specification, claims to be roughly 90% more efficient than a Nissan Leaf at 70 mph (110 kph). 6.5 miles (10.5km) per kWh for the Lightyear vs.3.4 miles (5.4km) per kwh for the 2020 Nissan Leaf Plus, with a similar capacity battery.Video posted earlier this week by Out of Spec Reviews:

author: coppice
author_rank: Super Contributor
timestamp: June 29, 2022, 10:31:41 am
content: Quote from: cortex_m0 on June 28, 2022, 11:55:48 pmHe thinks its refreshing that this company wants to talk about highway speeds, but of course they do. That plays to the strengths of their design. What happens when he tries twisty roads, and other complexity, where the handling is paramount? Various people have tried motors in each wheel, and are defeated by the awful handling with a large unsprung mass. When he talks about the light wheels and special tyres compensating somewhat for the weight of the motors, that's just another way of saying the put less rubber on the road to compensate for inherent poor handling.It looks like there are some interesting things in the design, especially its drag coefficient. Perhaps leaving out the gimmicky solar panels might have made people focus more on those.

author: Marco
author_rank: Super Contributor
timestamp: June 29, 2022, 03:25:34 pm
content: How well versed were those people in creating correction algorithms for the power steering?

author: thm_w
author_rank: Super Contributor
timestamp: June 29, 2022, 10:28:26 pm
content: Wheel motors have the best low speed performance at least, and should be able to accelerate faster from a stop

author: cortex_m0
author_rank: Regular Contributor
timestamp: June 29, 2022, 10:57:43 pm
content: Quote from: coppice on June 29, 2022, 10:31:41 amCertainly possible. I have zero expertise in why automobiles handle the way they do. I assume the Lightyear isn't trying to compete with a Land Rover, so maybe they think their customer won't care if this handles slightly worse than a Volkswagen Jetta.QuoteTend to doubt it. It's much harder to market efficiency, compared to "First Street-Legal Solar Automobile!"

author: nctnico
author_rank: Super Contributor
timestamp: June 29, 2022, 11:08:48 pm
content: Quote from: coppice on June 29, 2022, 10:31:41 amThere is nothing new about making a car with a low drag coefficient. Google 'hyper miling' and you'll see people have modified regular cars to a similar shape which improves the efficiency dramatically for many years. It is not a new design; just a matter of getting to public to accept a car which has such a long, odd shaped tail. The newest BEV from Mercedes uses a similar shape as well and they are not the only ones.

author: EEVblog
author_rank: Unknown
timestamp: June 30, 2022, 06:51:31 am
content: Quote from: coppice on June 29, 2022, 10:31:41 amThe solar panels are literally the only novel marketing point for a $250,000 EVSo it might be slightly better drag coefficient than other EV's, but that's kinda, meh.If it got say twice the efficiency of other EV's on the maket then you might have something worth bragging about, but it's WLTP figure is only slightly better than my 2020 IONIQ.

author: EEVblog
author_rank: Unknown
timestamp: June 30, 2022, 06:55:58 am
content: Quote from: cortex_m0 on June 28, 2022, 11:55:48 pmYet it's own marketing is aimed around less than 50km/day usage. So you won't be hitting highway speeds on big road trips.If this thing only cost a bit more than other EV's then they'd have something, but at $250k they have a gimmick that cashed up buyers can brag to their friends that they drive a solar powered EV.

author: EEVblog
author_rank: Unknown
timestamp: June 30, 2022, 06:58:23 am
content: Aptera on the 2nd channel for those that didn't see it:

author: iMo
author_rank: Super Contributor
timestamp: June 30, 2022, 08:43:51 am
content: EU agrees to end sales of combustion engine vehicles by 2035..

author: nctnico
author_rank: Super Contributor
timestamp: June 30, 2022, 09:34:56 am
content: Quote from: imo on June 30, 2022, 08:43:51 amNo, the EU plans to end sales of ICE cars by 2035. Nothing is cast is stone. There are several points in time where the plan is re-evaluated.

author: coppice
author_rank: Super Contributor
timestamp: June 30, 2022, 12:50:47 pm
content: Quote from: EEVblog on June 30, 2022, 06:51:31 amClearly this car is stupid as a product, simply due to the price, however....The low drag coefficient is the key thing this car brings. Sure, you can find lots of demos of achieving a super low drag coefficient in a similarly shaped one person vehicle, but they've made a comfortable family car which achieves similar results. The WLTP figures are notoriously unrealistic. The range of most EVs goes down badly at high speed, mostly due to drag. If their claims are genuine, this car achieves a much more consistent range as the speed varies. People don't want cars they either drive at full motorway speed and spend lots of time at chargers, or spend less time at chargers but drive quite slowly.

author: Marco
author_rank: Super Contributor
timestamp: June 30, 2022, 01:58:51 pm
content: WLTP is fine, with true independent testing (when a car manufacturer decides which lab to do business with, it's not independent). If you want to recalculate EPA for different speed conditions, you can. The results are public and EPA does confirmative testing.With WLTP half the data is private. EPA catches scammer where other countries do not.

author: golden_labels
author_rank: Super Contributor
timestamp: June 30, 2022, 02:05:37 pm
content: Quote from: nctnico on June 30, 2022, 09:34:56 amWhile normally I would frantically wave hands seeing “EU does foo”, in this caseimoseems to be right. This week member states came to an agreement, which makes that statement correct.(1)The details are basically set and it would be a rare occurance for EUParl to reject those amendments. The fact, that those are corrections to a pre-existing regulation(2), is important to see why it’s likely to see no further objections. Normally some factions would probably make an ineffective protest as a show for their electorate, but in this case a part of the framing is the situation with RF — so I suspect they may avoid even that kind of actions during the actual voting.It is also worth noting, that this does not eliminate internal combustion engines. Regulation’s scope is limited to passanger cars andLCVs. Any other vehicle group is still covered by the existing limits. And while currently no viable option exists, fuels offsetting CO2emissions are not explicitly excluded either.(1)https://www.reuters.com/business/sustainable-business/fight-over-funding-threatens-eu-deal-new-climate-laws-2022-06-28/(2)2019/631

author: iMo
author_rank: Super Contributor
timestamp: June 30, 2022, 03:31:16 pm
content: Imagine the EU highways in, say, year 2125 - speedy and beautifully smelling ICE vintage classic cars everywhere

author: nctnico
author_rank: Super Contributor
timestamp: June 30, 2022, 03:43:30 pm
content: Quote from: Marco on June 30, 2022, 01:58:51 pmI doubt that. The EPA fuel consumption numbers are typically on par with fuel consumption data collected by websites that track actual fuel consumption (collected from people that drive the cars around). WLTP data on the other hand is just nonsense.

author: Marco
author_rank: Super Contributor
timestamp: June 30, 2022, 05:09:51 pm
content: The WLTP drag coefficient numbers are not confirmation tested, it's just some bullshit from either the manufacturers or at best third party labs entirely dependent on their continued contracts.The problem is regulatory capture making the implementation of WLTP testing inherently corrupt. The test if honestly implemented is fine.

author: EEVblog
author_rank: Unknown
timestamp: July 01, 2022, 05:54:50 am
content: Quote from: coppice on June 30, 2022, 12:50:47 pmI'm betting the "Highway range" includes the small boost from the absolute best the solar panels can produce. It claims 10.7kWh/100km at 110kh/h.That's great, but not hugely or game changingly great, especially for the price. I'd have to double check my IONIQ, but IIRC it's in the order of 13-14kW/100km on the highway.

author: McBryce
author_rank: Super Contributor
timestamp: July 01, 2022, 07:36:50 am
content: Quote from: golden_labels on June 30, 2022, 02:05:37 pmIt will get interesting when they actually go to the bother of calculating how much electricity would actually be required to replace all ICE vehicles with EV. For a really rough estimate you can just check out the total energy delivered by petrol / Diesel imports to any country. Convert those billions of litres of fuel to watts and they will soon discover that we really need to start building a LOT of power stations / generators of some sort.McBryce.

author: golden_labels
author_rank: Super Contributor
timestamp: July 01, 2022, 02:33:22 pm
content: Quote from: McBryce on July 01, 2022, 07:36:50 amDunno who are “they”. But avoiding financial losses is part of the reason EC has issued the proposal. So that future tense regarding doing calculations is a bit weird. In particular since the summary of the calculations is in the document you are commenting on. Another part of the motivation is decreasing investment risk for what you considered the cost in your calculations, so the amendment is literally answering your concerns.Quote from: McBryce on July 01, 2022, 07:36:50 amAs clearly indicated in the amended regulation, in the discussed amendment, in associated media reports and in the post to which you reply: the 0g/km limit affects particular types of cars, and only new cars. Emission limits for pretty much entire industrial use of fossil fuels in vehicles are not zeroed. So the basic assumptions for the above estimation are already wrong. If they were not, you are still completely ignoring everything other than arbitrarily chosen costs and then compare that to… right, what exactly are you comparing it to?

author: McBryce
author_rank: Super Contributor
timestamp: July 01, 2022, 03:17:43 pm
content: With "They" I meant the politicians making these decisions. I am aware that my calculation is extremely rough and ignores lots of things, but it still doesn't change the fact that we will not have even close to enough electricity generation capacity for all of the EV on the road by 2035.I am also aware of the details (new cars only etc), but even in this case many countries will be forced to build many new power stations to cope with even this and many countries haven't even started to increase generation at the rate we would need to charge the EV's.So yes, sloppy maths, but it doesn't change the result: Not enough electricity generation or plans for new generators to cover the situation in 2035.McBryce.

author: nctnico
author_rank: Super Contributor
timestamp: July 01, 2022, 04:18:54 pm
content: Quote from: McBryce on July 01, 2022, 03:17:43 pm'Hydrogen' is the word you are looking for. The EU doesn't plan for all cars have to be BEVs; just that all new cars have no CO2 emissions.

author: Marco
author_rank: Super Contributor
timestamp: July 01, 2022, 10:02:29 pm
content: Talking about hydrogen, I notice that farther in the past with just as much knowledge of the technical hurdles as now, and with actual running prototypes, liquid hydrogen was seen as a perfectly realistic solution even for passenger cars. Then somewhere along the way it got shoved to the side for the totally unworkable compressed hydrogen ... and I can't really understand why. Liquid hydrogen has downsides, but nowhere near as many as compressed.The hydrogen evaporates eventually ... but ehh, so what? If it's connected to your inverter the evaporated hydrogen can be converted to electricity, so it doesn't entirely go to waste. To handle it running dry, have a limp to the pump battery pack in there too (good for heating up the fuel cell too when needed). Need to figure out some way for roadside assistance to attach a range extender so toeing the entire car doesn't need to become the go to for running out of hydrogen and power, a small hitch specifically designed for a toed battery pack perhaps?Ignoring whether hydrogen is practical at all for a moment, I think liquid makes the most sense even for passenger cars.

author: McBryce
author_rank: Super Contributor
timestamp: July 02, 2022, 07:56:44 am
content: Quote from: Marco on July 01, 2022, 10:02:29 pmBecause a tank of liquid hydrogen wouldn't get you very far. Liquid Hydrogen has an energy density of 2.8kW/h per litre, Compressed Hydrogen is 33.6kWh/kg. You'd need a massive tank of liquid hydrogen to get a decent range.The other question is, where is all this hydrogen going to come from? There's no sources of natural hydrogen on this planet. There are a few other processes that produce it as a by-product, but not in the quantities required and other methods of producing it require massive amounts of energy and have high losses.A third, rarely mentioned issue, is that most hydrogen is not 100% pure. It has impurities that gunk up the fuel cell pretty quickly. Most vehicle fuel cells only last a short time before they start failing.McBryce.

author: iMo
author_rank: Super Contributor
timestamp: July 02, 2022, 08:12:07 am
content: I talked recently to a guy working in a company messing with car chargers. Asked him the question on where all the energy comes from. He told me the energy, e.g. from nuke power plants, is here 24x7 in a constant amount, but most electricity is burned by the users in 2 peaks during the day and by industry 1/3 of the day. By creating a constant load during the day and night you may use it for charging all the cars (he told me "happily"). I am still pretty skeptical on it, though.PS: Also with the news on the EU plan with ICE I registered an info (I do not have the source handy) "they" consider to double the EU nuke power station electricity production by 2050..

author: McBryce
author_rank: Super Contributor
timestamp: July 02, 2022, 08:32:18 am
content: Well I just did a closer calculation using real numbers, and using Germany as an example:Germany produced 579 Billion kWh in 2021. In 2021 it sold 20.5 Million tons of petrol at the pumps (just petrol, diesel not included). A litre of petrol has 12.2kWh/kg. So the petrol sold was equivalent to approx 250 Billion kWh of electricity, meaning that Germany would need almost 50% more generation just to cover the petrol cars.Not forgetting, 2021 was Covid shutdown, more electricity being used in home office and less petrol needed to drive to work.The currently planned new power stations in Germany don't even cover the capacity that nuclear and coal fired generation supplied and which are now being shut down. So Germany is definitely not in a position to support this and I would guess that many other (non-nuclear) EU countries are in a very similar situation.McBryce.*All figures taken from Germany government sites.

author: iMo
author_rank: Super Contributor
timestamp: July 02, 2022, 08:40:19 am
content: Yep, EU has to reconsider the feasible energy sources.. EU and especially Germany had nice green project plans, but they did not evaluate all potential risks in their planning, like ie. the war in Europe. So they have to change their plans, it seems. In project management it is called a "change management process" which may result in more required resources, efforts, time (and $$)..

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 08:51:12 am
content: Quote from: McBryce on July 02, 2022, 07:56:44 amTo reiterate the question, why was liquid hydrogen abandoned in favour of compressed hydrogen for passenger cars. Your supposed answer (you said "because") was energy density. Obviously the energy density and energy per weight including tank for compressed hydrogen are both far inferior, so it's irrelevant to the question at hand.To address your tangent though, fuel cells are more efficient than ICE's and increasing a fuel tank by 50% in each dimension won't make it suddenly impossible to build a passenger car around it. Just like hydrogen aeroplane designs, the car designs can adapt.QuoteElectrolysis of RO water has a lot less possible sources of contamination than from natural gas processing.PS. I think material for PV can be massively reduced by moving to flexible solar mounted on plastic cushions inflated with expanding foam. Hail resistance can be handled likethis. Etc. There's orders of magnitude of room to improve gigascale PV. That's where hydrogen will come from, if civilization persists.

author: McBryce
author_rank: Super Contributor
timestamp: July 02, 2022, 09:20:33 am
content: Quote from: Marco on July 02, 2022, 08:51:12 amI'm not sure I understand what you mean. The tanks weight isn't really a factor here. Liquid hydrogen only has 2.8kWh/l. Petrol is 9.7kWh/l. So I would need a tank of about 3x the size of a current petrol tank to get the same range. I also need to drag this weight around with me. With compressed hydrogen I have 3x the density of petrol, so for the same range, the tank only needs to hold a third of the volume.As for impurities. I've worked on two commercial Fuel cell vehicle projects. The fuel in both cases was produced using electrolysis and the fuel cells only had a meaningful life of just over 3 years before they were too gunked up to work efficiently. Additionally, producing hydrogen using electrolysis is incredibly inefficient (as low as 70%), so why not just use the electricity in a BEV instead of wasting 30% of the energy converting it to hydrogen?McBryce.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 09:26:15 am
content: To reiterate the question, why was liquid hydrogen abandoned in favour of compressed hydrogen for passenger cars. Your supposed answer (you said "because") was energy density. Obviously the energy density and energy per weight including tank for compressed hydrogen are both far inferior, so it's irrelevant to the question at hand.

author: McBryce
author_rank: Super Contributor
timestamp: July 02, 2022, 09:35:36 am
content: Quote from: Marco on July 02, 2022, 09:26:15 amBoth far inferior to what? I can't answer this any simpler: To go the same distance, one needs a big heavy tank full of heavy fuel, the other needs a much smaller tank of equally heavy fuel. The weight of the tanks aren't much different per volume.McBryce.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 09:45:24 am
content: You can't answer it period, because you aren't reading the question.Why was liquid hydrogen abandoned in favour of compressed hydrogen for passenger cars.

author: wraper
author_rank: Unknown
timestamp: July 02, 2022, 09:53:25 am
content: Quote from: McBryce on July 02, 2022, 07:56:44 amAnd way more massive tank of compressed hydrogen. You compare apples with oranges. Liters with kilograms. For water the same number means equal amount but not for hydrogen.Do you not see a problem in storing liquid hydrogen? Unless you keep it colder than -253oC it will turn into gaseous form, so you need very good thermal insulation and to either let excess gaseous hydrogen into atmosphere to prevent the tank from rupturing or cool it by some means.

author: wraper
author_rank: Unknown
timestamp: July 02, 2022, 09:57:30 am
content: Quote from: McBryce on July 02, 2022, 09:35:36 amThe same amount of hydrogen in liquid and compressed form weights the same, but compressed hydrogen takes much larger volume thus needs much larger tank which also must be able to survive extremely high pressure.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 10:09:49 am
content: Quote from: wraper on July 02, 2022, 09:53:25 amI was the one promoting liquid hydrogen, he was answering questions which weren't being asked.I see the challenges of liquid hydrogen, but I don't judge them qualitatively different than liquid natural gas. A cryogenic fuel being commercially used in trucking today.There's problems and risks, there are solutions and mitigations. The lack of energy density and charge-speed/grid-load of batteries is also a problem, the far far worse round trip efficiency of synthetic fuels made from green hydrogen is also a problem. The arable land and water use of biofuels is also a problem.Which are the bigger problems?

author: wraper
author_rank: Unknown
timestamp: July 02, 2022, 11:43:50 am
content: There is a big difference between storing at -253oC and -162oC for LNG, even latter makes it very niche and troublesome. Not to say LNG has almost an order of magnitude higher density which require way smaller tank to be kept cool. Neither is a good option for any use that will be significantly intermittent. Basically fill and spend as fast as you can is the only viable option solution when using these.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 12:56:51 pm
content: BMW 750hl supposedly had about 1.2W heat ingress, that's about the latent heat of 2 mg of hydrogen per second. Lets say 5 kg of hydrogen tank, so that has a life of roughly a month. Lets say you include a small lithium ion battery and have the car run that down first. When you park the car, the evaporated hydrogen would first go to charging the battery.It would require a different mindset from a fossil fuel car or EV, but I wouldn't say it's completely unusable simply because of evaporation.

author: McBryce
author_rank: Super Contributor
timestamp: July 02, 2022, 01:48:53 pm
content: Quote from: Marco on July 02, 2022, 09:45:24 amIt seems I really don't understand the question. All I can say is that I've seen the solutions for both systems in real hardware and the compressed gas solution was viable to put in a car for the ranges required with enough room for all the other things a customer would expect in a vehicle and the liquid version was not. Either way, neither are a viable solution as long as we don't have an efficient method of producing vast quantities of Hydrogen, which we still don't.Maybe I need to ask the question: Ignoring the energy density aspect. We know the difficulties of keeping Hydrogen in a liquid form, very low temperature which requires both insulation and an energy source. To keep gas at pressure we just need a robust container. So tell me, what advantages do you see that liquid Hydrogen has over compressed gas?McBryce.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 02:37:04 pm
content: Quote from: McBryce on July 02, 2022, 09:20:33 amI'm sorry I missed this ... in my defence, it's a really bizarre thing to say. Hydrogen can actually be liquid at room temperature, but it takes a hell of a lot more than 700 bar. Outside of extreme corner cases which are not relevant here, a gas of a molecule isn't going to be more dense than a liquid regardless of temperature and pressure.The density of hydrogen at 700 bar at room temperature is 42 kg/m3, the density of liquid hydrogen at -252.87°C is 71 kg/m3. Compressed hydrogen has even worse energy density than liquid hydrogen, as common sense dictates. That said, I had never really looked at the Mirai tanks and it is kind of impressive how thin and light they were able to make a 700 bar tank. Eyeballing it the 750hl managed to pack it's 8kg of hydrogen in far less space including the necessary equipment than Mirai's 5 kg.

author: tszaboo
author_rank: Super Contributor
timestamp: July 02, 2022, 03:10:13 pm
content: Quote from: Marco on July 02, 2022, 09:26:15 amBecause hydrogen is explosive. You can blow up it in the air, by shorting out something like a 10uf capacitor, that is charged up to 10v. That tiny spark has enough energy to blow up the car in your garage.Quote from: wraper on July 02, 2022, 11:43:50 amLNG is nice if you have a large tank that is maintained constantly. The issues start coming when that tank is actually used. So they never empty out LNG tanks to 0%. And when they are almost empty, the heat capacity decreases dramatically, while the heat gain of the tank is the same. So pressure builds up in them as the remaining LNG evaporates. And you can blow up an almost empty tank in a few days.CNG is much safer for cars, because the tank is actually designed to handle the high pressure.But I'm a fan of CNG. As I recall 60-80% of the car fleet could be converted to Petrol/CNG hybrids, significantly reducing the need for petrol. And we can create CNG from CO2 and water and solar or wind power. It's not perfect, but it would be a significant reduction of fossil fuel usage, even without the massive environmental need to make BEVs for everyone.

author: nctnico
author_rank: Super Contributor
timestamp: July 02, 2022, 04:06:50 pm
content: Quote from: tszaboo on July 02, 2022, 03:10:13 pmThis is FUD. In the end the same is true for fuel vapour. Why do you think fuel systems in cars are hermetically sealed? Research has shown that hydrogen has no higher risk of fires or explosions compared to other fuels used in cars.

author: McBryce
author_rank: Super Contributor
timestamp: July 02, 2022, 05:25:49 pm
content: Quote from: nctnico on July 02, 2022, 04:06:50 pm?? Show me the research that says that.McBryce.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 06:03:18 pm
content: Quote from: tszaboo on July 02, 2022, 03:10:13 pmDetonation actually requires a higher percentage than gasoline vapour, I don't see it happening in my garage. It's highly flammable.

author: wraper
author_rank: Unknown
timestamp: July 02, 2022, 09:04:08 pm
content: Quote from: McBryce on July 02, 2022, 09:20:33 amWith compressed hydrogen you have 2 times worse density that liquid hydrogen, thus 6 times worse than gasoline. Dunno from where you got an idea it should be somehow better.

author: tszaboo
author_rank: Super Contributor
timestamp: July 02, 2022, 09:33:31 pm
content: Quote from: nctnico on July 02, 2022, 04:06:50 pmI actually know what I'm talking about, having several devices certified for such an environment.And read this:https://marketresearchtelecast.com/hydrogen-bus-catches-fire-in-the-netherlands/190175/Hydrogen is no joke, you put that in an enclosed environment, and it creates some ventilation for itself by launching the roof to next town.

author: Marco
author_rank: Super Contributor
timestamp: July 02, 2022, 10:26:22 pm
content: Quote from: tszaboo on July 02, 2022, 09:33:31 pmSpill gasoline in a closed garage and it can explode too (actual detonation).

author: nctnico
author_rank: Super Contributor
timestamp: July 02, 2022, 11:48:02 pm
content: Quote from: tszaboo on July 02, 2022, 09:33:31 pmThen I suggest you to get a job at the car manufacturers and warn them. The reality is that the SAE, regulatory bodies and car manufacturers have designed and certified the hydrogen storage and fueling systems for vehicles to be safe. These people aren't stupid! You might think you know what you are talking about but you are missing the point that the hydrogen systems have been designed to be safe to use.Linking to articles that don't actually support your claim doesn't really help. It only shows the attempt to spread more FUD. I tried to dig a bit deeper but there is no mention of hydrogen being the cause of the fire affecting the hydrogen busses or that the tanks with hydrogen exploded.

author: tszaboo
author_rank: Super Contributor
timestamp: July 03, 2022, 07:39:11 am
content: Quote from: nctnico on July 02, 2022, 11:48:02 pmCar makers put lead into gasoline, cheated with diesel NOx emissions and spent decades only putting seatbelt on the front, or released pre-alpha versions of the self driving software that drove cars into brick walls and trucks.I trust politicians better than carmakers, while both usually are spineless weasels who do anything for money.Quote from: Marco on July 02, 2022, 10:26:22 pmYes. It needs to evaporate first. And you need something like three to six magnitude less energy to ignite hydrogen than petrol.

author: quarros
author_rank: Regular Contributor
timestamp: July 04, 2022, 03:53:44 pm
content: Dave. One thing in both the original and extended video stood out for me, regarding the Aptera.I completely agree that with any normal EV the achievable range is greatly reduced by the speed increase. But with the drag coefficient of 0.13 (If their presented numbers are to believed), isn't this effect largely reduced? My memory about fluid dynamics are quite foggy but I faintly remember that the Drag Force / Velocity curve changes by the value of the drag coefficient, and this change is not linearly but exponentially proportional to the change of the coefficient. So this funky little car is more than likely be able to drive at highway speeds without significant loss of range.Any automotive or aerospace engineer Please Correct me if what I say is nonsense.Edit: After looking it up, it seems I remembered wrongly. Drag force is calculated by Fd= cd*0.5*p*v2*A formula. So the value changes in cdare not exponentially changing the drag force. I think the reason why I remembered wrong was the A value. Which is the "characteristic frontal area of the body" in square meters, and that is always in some relation to the shape of the design. In conclusion my original guess is still likely right because the area of the frontal body on an Aptera is also smaller than most cars.

author: thm_w
author_rank: Super Contributor
timestamp: July 04, 2022, 09:27:25 pm
content: Quote from: McBryce on July 02, 2022, 08:32:18 amYou are assuming gas cars are 100% efficient with that calculation, which they are not, an EV is something like 75%.Quote from: quarros on July 04, 2022, 03:53:44 pmYeah I'm sure you can find an online calculator to plug in and compare, but, you'll have to find frontal area, which no one seems to publish.Big boxy front cars are currently in style and have horrible efficiency.Quote from: EEVblog on July 01, 2022, 05:54:50 am13.8 kWh according to these guys at 110km/h, which was the best result:https://insideevs.com/reviews/443791/ev-range-test-results/Tesla Model 3 a close 2nd.Cant believe how much worse the 2022 model is, 20kWh/100km, marketing must have taken over.

author: cortex_m0
author_rank: Regular Contributor
timestamp: July 04, 2022, 11:21:15 pm
content: Quote from: thm_w on July 04, 2022, 09:27:25 pmThe Ioniq and Ioniq5 are not related vehicles. The Ioniq5 is bigger and heavier: 30cm more wheelbase, 7cm wider, 15cm taller, and most importantly at least 350kg heavier (more with the bigger battery packs and AWD)Notably the AWD car that InsideEVs tested has a manufacturer rated range of 76km less than the RWD version, owing to the heavier weight and higher friction.The most efficient version of the Ioniq5 is (US EPA estimated) at 16.4 kWh/100km.

author: McBryce
author_rank: Super Contributor
timestamp: July 05, 2022, 08:05:20 am
content: Quote from: thm_w on July 04, 2022, 09:27:25 pmI deliberately left all efficiencies out of the equation because otherwise we would have to compare all efficiencies such as how efficient the refrigerator for liquid hydrogen, the compressor for compressed hydrogen, the charging circuitry etc.There are some really good "Well to wheel" comparisons available that do this, even comparing the different methods of producing Hydrogen. They show very clearly why a battery EV is the most efficient alternative to fossil fuels. Here's a simpler BEV/Hydrogen one from VW:https://www.volkswagenag.com/en/news/stories/2019/08/hydrogen-or-battery--that-is-the-question.html#McBryce.

author: Marco
author_rank: Super Contributor
timestamp: July 05, 2022, 01:54:53 pm
content: Talking about the cost of electricity without mentioning time is bullshit. Assuming Nuclear is not an option, then 2050 we will need massively overprovisioned renewables. Assuming the capital costs of electrolyzers and cryopumps is relatively small, efficiency won't matter. A huge hydrogen economy will be able to get surplus electricity for almost nothing.

author: cortex_m0
author_rank: Regular Contributor
timestamp: January 28, 2023, 01:57:42 pm
content: Lightyear announced this week they will not produce the Zero.https://electrek.co/2023/01/23/lightyear-0-production-affordable-lightyear-2-solar-ev-wait-list-registrations/

author: spostma
author_rank: Regular Contributor
timestamp: January 28, 2023, 10:07:05 pm
content: Lightyear is largely bankrupt (their production daughter company Atlas Technologies), over 600 people lost their jobs,just 30 people remain in mother company that owns the intellectual property and patents as far as I understand.170 Million Euros investment money down the drain,and people that did an advance payment for the Lightyear 0 lose their money, sadly.Dutch articles with more info (use Google Translate):https://www.rtlnieuws.nl/economie/bedrijven/artikel/5361810/faillissement-zonneauto-lightyear-600-werknemershttps://www.linkedin.com/news/story/lightyear-deels-failliet-5099617/

author: coppice
author_rank: Super Contributor
timestamp: January 28, 2023, 10:18:15 pm
content: Quote from: spostma on January 28, 2023, 10:07:05 pmWho puts down more than a small deposit for something like this from a company with no track record, that could just as easily be a scam as a genuine effort to build a new business?

author: Marco
author_rank: Super Contributor
timestamp: January 28, 2023, 10:20:57 pm
content: Bankruptcy is a good way to lower NRE and capital costs. That factory is there now, might as well build cars with it.I wouldn't be surprised that in the limit case you could halve the cost of the car, it's not like another car manufacturer at the moment is going to pay top dollar for that factory at the moment ... so investors would be competing against scrap prices, there's some opportunity here for it to rise from the ashes.

author: ataradov
author_rank: Super Contributor
timestamp: January 28, 2023, 10:25:21 pm
content: Quote from: coppice on January 28, 2023, 10:18:15 pmSame people that buy JPEGs of monkeys. I suspect a lot of their troubles also relate to cryptobros no longer being able to afford lambos and this stupidity.

author: tszaboo
author_rank: Super Contributor
timestamp: January 28, 2023, 10:49:54 pm
content: Quote from: spostma on January 28, 2023, 10:07:05 pmOh, wow, I had a job interview there last November. I cancelled the followup. I guess I dodged a bullet here.

author: EEVblog
author_rank: Unknown
timestamp: January 29, 2023, 12:10:09 am
content: Yep, bankrupt.https://innovationorigins.com/en/selected/car-builder-solar-car-lightyear-0-bankrupt/I called it a few days before it happened, LOLhttps://twitter.com/eevblog/status/1617815544148955137

author: ataradov
author_rank: Super Contributor
timestamp: January 29, 2023, 12:44:44 am
content: I guess it is fine if you are playing with other people's money, but really, it should have been obvious that stating with $40K model gives you a way better chance or survival.Just making a plain $40k EV is already a decent achievement. You can sell this alone. Any other gimmicks on top of that is just a plus.

author: coppice
author_rank: Super Contributor
timestamp: January 29, 2023, 03:22:43 pm
content: Quote from: ataradov on January 29, 2023, 12:44:44 amA startup has zero chance of survival if it can't offer something new and different. A number of people now make a $40k EV. Unless the value proposition of a startup's cars, cheap or expensive, is profoundly different from anything available from an established brand, with their established support network and reasonable chance of parts availability, a startup can't compete.

author: nctnico
author_rank: Super Contributor
timestamp: January 30, 2023, 12:29:06 am
content: Quote from: Marco on January 28, 2023, 10:20:57 pmAgreed. Only the manufacturing part of the company behind the Lightyear cars is affected. The IP and solar panel production is not included in the bankrupty. Interestingly the new Toyota Prius has the option to have a solar panel in its roof so I guess the idea of having solar panels on a car did got traction.

author: EEVblog
author_rank: Unknown
timestamp: January 30, 2023, 01:06:00 am
content: Quote from: nctnico on January 30, 2023, 12:29:06 amSeems like an obvious marketing opportunity.It's a balance of integrated manufacturing cost though.

author: EEVblog
author_rank: Unknown
timestamp: January 30, 2023, 01:07:10 am
content: Quote from: coppice on January 29, 2023, 03:22:43 pmYep. At least the Apera looks fantastically futuristic, will sell well on that alone. Heck if they were available in Australia then I might buy one.EDIT, just saw this:https://thedriven.io/2023/01/25/aptera-to-launch-solar-powered-ev-in-2023-but-australia-will-have-to-wait/

author: tszaboo
author_rank: Super Contributor
timestamp: January 30, 2023, 08:50:40 am
content: Quote from: nctnico on January 30, 2023, 12:29:06 amMy 12 year old prius 3 has a solar panel on it. They never sold this variant here in the NL.For the ugly duckling it is, it looks a bit better with the solar panel.

author: McBryce
author_rank: Super Contributor
timestamp: January 30, 2023, 09:44:38 am
content: Quote from: EEVblog on January 30, 2023, 01:07:10 amWhat sort black magic trickery are they doing to get that through homologation??!!! That's every safety engineers nightmare.McBryce.

author: thm_w
author_rank: Super Contributor
timestamp: January 30, 2023, 09:58:11 pm
content: Quote from: ataradov on January 28, 2023, 10:25:21 pmI'm not a fan of crypto, but this has nothing to do with that.If you want to draw parallels, we have kickstarter, indiegogo, and others where people throw money at unviable projects.The car cost ~$160k, a deposit of $4k to someone who can afford 160k is not very much (2.5% of the total price).https://web.archive.org/web/20220210171049/https://lightyear.one/reserve

author: nctnico
author_rank: Super Contributor
timestamp: January 30, 2023, 10:37:53 pm
content: Quote from: McBryce on January 30, 2023, 09:44:38 amLikely it is classified as a trike / motorcycle.

author: coppice
author_rank: Super Contributor
timestamp: January 30, 2023, 11:39:16 pm
content: Quote from: nctnico on January 30, 2023, 10:37:53 pmThe rules for bikes, trikes and quadricycles seem based on the idea that if you make the machine unsafe enough its OK for all the safety rules to go away.

author: tszaboo
author_rank: Super Contributor
timestamp: January 30, 2023, 11:44:16 pm
content: Quote from: coppice on January 30, 2023, 11:39:16 pmYeah, but you get a steady stream of otherwise healthy organ donors.

author: ataradov
author_rank: Super Contributor
timestamp: January 30, 2023, 11:49:35 pm
content: Quote from: thm_w on January 30, 2023, 09:58:11 pmYeah, but why? What is the logic behind doing that? $4k from a customer is not enough to fund development of a $160k car, even if you have a lot of people willing to pay. I guess if you really want to be the first one to have it, but this in itself is a bad idea.It is like pre-ordering digital games and then being disappointed when the game is crap.

author: thm_w
author_rank: Super Contributor
timestamp: January 31, 2023, 12:35:51 am
content: Quote from: ataradov on January 30, 2023, 11:49:35 pmIt gets you emotionally invested in the product, while gauging serious interest. Maybe you put 4k in, so you are less likely to buy another car that comes up for sale, as you've already "decided", no idea.The initial Tesla pre-orders were $5k? But they've done $100, $250, $500, and $1k, for deposits as well. So maybe lower deposits work better to get more people interested, even if half bail, you've made money on interest and generated hype.QuoteYes exactly. I'm sure there are some studies but I can't find anything goodhttps://www.sciencedirect.com/science/article/abs/pii/S0969698913001148

author: EEVblog
author_rank: Unknown
timestamp: January 31, 2023, 01:23:09 am
content: Quote from: tszaboo on January 30, 2023, 08:50:40 amIsn't the Prius panel just for trickle charging the 12V auxillary battery?

author: thm_w
author_rank: Super Contributor
timestamp: January 31, 2023, 01:40:58 am
content: Quote from: EEVblog on January 31, 2023, 01:23:09 amIt just runs a fan on the older models apparently:https://www.boronextrication.com/2011/08/13/prius-solar-panel-roof-option/On the Nissan Leaf it charges the aux 12V battery.Kinda useful if you rarely drive the car, but only because of the use of a separate 12V battery in the first place, which is a design compromise.

author: EEVblog
author_rank: Unknown
timestamp: January 31, 2023, 02:23:01 am
content: Quote from: thm_w on January 31, 2023, 01:40:58 amAFAIK all EV's have an auxillary 12V battery for system separation reasons.

author: McBryce
author_rank: Super Contributor
timestamp: January 31, 2023, 08:40:58 am
content: Quote from: EEVblog on January 31, 2023, 02:23:01 amYeah they all do, but not just for seperation. Many systems (Central locking, alarms etc) need to be running even when the HV battery and DC/DC are powered down. The HV system only gets activated when the user actually wants to move the vehicle and during charging.McBryce.

author: coppice
author_rank: Super Contributor
timestamp: January 31, 2023, 12:44:59 pm
content: Quote from: EEVblog on January 31, 2023, 02:23:01 amIf for no other reason, they need a low voltage battery to pull in the breaker for the high voltage battery. Without that its hard to make the car both safe and convenient.

author: coppice
author_rank: Super Contributor
timestamp: January 31, 2023, 12:48:37 pm
content: Quote from: McBryce on January 31, 2023, 08:40:58 amMost current EVs will pull in the high voltage breaker from time to time, as the 12V battery runs down, to recharge it. This is so a pretty small 12V battery can be used. This behaviour can be disable, so the high voltage battery won''t kick in during maintenance work. Charging of the 12V battery is largely decoupled from charging of the car.

author: McBryce
author_rank: Super Contributor
timestamp: January 31, 2023, 01:59:50 pm
content: Quote from: coppice on January 31, 2023, 12:48:37 pmTrue, forgot that situation.McBryce.

author: EEVblog
author_rank: Unknown
timestamp: January 31, 2023, 10:29:48 pm
content: Quote from: McBryce on January 31, 2023, 01:59:50 pmMy IONIQ flashes it's big blue LED occasionally at night indicating that the 12V battery is being charged from the main pack.

author: nctnico
author_rank: Super Contributor
timestamp: January 31, 2023, 10:36:52 pm
content: Either way the solar panel would help save some energy. I'd still be interested in whether solar panels on cars can also charge the main battery. But it is also possible that the electronics that need to be on draw more power compared to the energy coming in. Recently I read an article (IIRC originating from the German automobile owners club ADAC) that some BEVs lose up to 30% while / when charged from a regular 16A / 230V outlet due to all the systems that need to be on during charging the main battery.

author: thm_w
author_rank: Super Contributor
timestamp: January 31, 2023, 10:50:47 pm
content: Quote from: nctnico on January 31, 2023, 10:36:52 pmIf its having to warm or cool the battery pack that would be a large part. I assumed it was mostly AC/DC conversion losses, I2R loss, etc. as charging at 120V/L1 is less efficient than 240V/L2 (~85% vs 90%).But good point about systems that would come on. Probably makes no sense to charge the main battery unless you are getting >100W of solar power coming in say.https://ieeexplore.ieee.org/document/7046253

author: tszaboo
author_rank: Super Contributor
timestamp: January 31, 2023, 11:04:02 pm
content: Quote from: thm_w on January 31, 2023, 01:40:58 amHey, you are not supposed to know thatYes, it cools down the car during the summer. I would argue that bottom line, it still saves on the AC therefore fuel.Plus, you know it's still a solar panel on a hybrid.

author: EEVblog
author_rank: Unknown
timestamp: February 01, 2023, 04:44:31 am
content: Quote from: tszaboo on January 31, 2023, 11:04:02 pmThe marketing strategy is simple, put a solar panel on the EV and let Joe Average consumer think it's for the main battery because they don't know any different, even if you tell them in the fine print

author: nctnico
author_rank: Super Contributor
timestamp: February 03, 2023, 12:15:07 am
content: According to a quick Google, the 2022 model Prius that is about to hit the market does charge it's main batteries (the ones used to power the electric motor) from the optional solar panel.

author: PA0PBZ
author_rank: Super Contributor
timestamp: April 08, 2023, 10:52:47 am
content: Anyone wants to buy one?https://www.troostwijkauctions.com/uk/auction/01-46135/

author: EEVblog
author_rank: Unknown
timestamp: April 10, 2023, 12:13:46 am
content: Quote from: PA0PBZ on April 08, 2023, 10:52:47 amIf it was here I'd buy one kicks.

author: nctnico
author_rank: Super Contributor
timestamp: April 10, 2023, 08:35:53 am
content: How much would it cost to transport?

author: PA0PBZ
author_rank: Super Contributor
timestamp: April 10, 2023, 08:44:54 am
content: Quote from: nctnico on April 10, 2023, 08:35:53 amUSD 1500-2000

author: McBryce
author_rank: Super Contributor
timestamp: April 10, 2023, 09:49:59 am
content: Transporting an EV battery that isn't installed in a vehicle can be quite a complicated matter in Europe (and probably other places too). If it's a new (and certified) battery you have to at least be ADR2021 compliant, ensuring that the transport vehicle and packaging is sufficient and (I think) even the driver needs to have certain training. If the battery is a prototype with no type approval or crash test documentation, things get extremely complicated, especially if you need to cross a border with it. It's not a matter of throwing it on the back of the truck and off we go.I assume that these credentials would need to be confirmed before they let anything go out the gate.McBryce.

author: SiliconWizard
author_rank: Super Contributor
timestamp: April 13, 2023, 12:07:06 am
content: Quote from: EEVblog on February 01, 2023, 04:44:31 amYes, though I think we could extend your statement a little bit.Quote