gangzoom

For those interested here are some of the scientific literature on battery development and fuel cell development - You will need institution/subscription access to 'Nature' but your local library should be able get PDF copies if you request them - 'Nature' for those who don't know, is the most prestigious peer reviewed scientific journal on the planet - Its 'impact factor' is more than that of a leading medical journal like the 'Lancet'....Most established Professors dream of getting a Nature publication, so what they print is about as accurate as it gets with our current 'peer review' system. http://www.nature.com/nclimate/journal/v5/n4/full/nclimate2564.html http://www.nature.com/news/the-rechargeable-revolution-a-better-battery-1.14815 http://www.nature.com/nature/journal/v414/n6861/full/414345a0.html http://www.nature.com/nature/journal/v486/n7401/full/nature11115.html So as I've said, don't take my word for any thing, do your own research into the topic and than come up with your own opinions....

What do you mean unwilling to acknowledge what?? That thing I said in the rest of the sentence... You mean the abit about EVs not been the perfect solution etc.... Again I point out I OWN and USE an EV everyday for the last 3 months, and I now no intention of spending a single £ on any ICE car ever again. EVs may not be 'perfect' but for me and through my experience of living with one they are a far more 'perfect' than any ICE car I've owned before. I'm slowly managing to convince my wife of this. She even admitted this weekend that the Leaf is quieter to drive than her Lexus. Personally I would rather replace the Lexus with a Tesla, rather than hand the Leaf back for a Tesla. Everyone is free to make up their own minds, my views and decisions are based on my personal experiences, which is what I'm sharing with people. You don't have to like it, but please don't try to make out I have no idea what I'm talking about. I may not be a chemist or engineer by trade but studied maths, chemistry and physics at A-level (Achieved A grades on all three topics - we didn't have A* grades back than ), and mechanical/aeronautical engineering at Cambridge with a view of trying to get a job at JPL was one of my 'fall back' career options. Though you can argue Imperial or MIT are just as good/better than Cambridge these days. So I'm pretty confident in my ability to critically appraise scientific literature- which actually is one of my day to day jobs. I don't know about you guys, but I certainly don't enjoy throwing away money, and when it comes to making £50K + purchasing decision, it's not something I'll do without ALOT of thought and consideration - Hence all the research I've done into Tesla. If it was your £50K would you not do the same?? My only 'doubt' about Tesla comes from my own indecision about spending an 'affordable' amount of money on lower spec 320bhp 70D Model S, or just go mental and try to gather up enough funds for the 691bhp P85D....I'm waiting for Tesla UK to get hold of a RHD P85D, and than I'll book a test drive. But will be bringing my wife along to make sure I don't do something silly, like buy a £80K+ car on the spot with money I don't have

What do you mean unwilling to acknowledge what?? As far as I'm aware am the only person on this forum using an EV day to day, the Leaf has covered more than 1600 miles now in just over 3 months. I've yet to come across a single issue with regards to 'range anxiety'. Yes it's not very good if you want to cover 200 miles non-stop, but that the kind of trip I only do 5% of the time. Having two cars in the family mean that's a none issue anyway. In the next 20 months if I can persuade my wife I'll happily get rid of our Lexus for Tesla. I have no concerns at all about two battery EVs on our driveway - Given a Model S has close to 300 mile range if needed. As far as I'm concerned even the current generation EVs are already good enough to replace our old ICE cars. I'll carry on updating people with my EV experience. If you think am talking rubbish you can simply ignore me, as I've said before its my money I'm spending/wasting

Feel free to ignore me as a crazy mad man wasting his time and money on something pointless

Unlike batteries, which don't use any precious metals at all in their production... It never ceases to amaze me just how blinkered you come across on this topic, it's quite mesmerising at times. Batteries are far easier to mass produce than hydrogen fuel stacks. Lithium and Cobalt are more abundant than Platinum - Ask your wife/significant other if what precious metal ring they rather have - Lithium or Platinum. I'm blinkered about EVs because once you start really looking into the arguments regarding moving away from fossil fuels than the solution is actually very clear and obvious. Don't take my word for it, go and read the research/papers your self.

On the flip side of that PR announcement... "Tesla posted quarterly revenue of $939.9 millions, a gain or nearly 52% over the same period last year. However, Tesla also reported a loss of $154 million in the quarter, or $1.22 per share, which is more than three times the $49.8 million loss the company posted in last year's first quarter." "Over the first two quarters of the year, Tesla hasn't delivered even half of the 55,000 vehicles it promised for the year." Source 1 Source 2 Now, that's not saying that Tesla are not also making positives, but I think it's important to note that they're not the flourishing beacon of success that they appear on the surface. What with the catastrophic failure of the Space X launch too, Musk is going to be a very busy boy in the coming months. If Tesla stopped now, they couldn't easily sustain themselves as a niche player like Porsche, Jaguar. BUT Musks ultimate goal is produce an EV for the mass market. Tesla is taking a massive gamble with building the worlds largest battery factory at a cool cost of $5 billion - which is $1 billion more than what Toyota is trying to raise through stock options to continue and develop the Miria. When fully complete its going to have a production output BIGGER than every other battery factory put together in the whole world!! No one has tried anything like this before, the investment needed in the battery factory is far bigger than the costs involved with developing cars. IF Tesla can pull this off, selling batteries will be their main business... If I was a investor I wouldn't touch Tesla with a barge pole, there are so many 'risks' in the battery factory, and even Musk has said they don't known how the production process will run....BUT the shell of the 'test' factory is already nearly done, and production due to start in Q3 2016. These are some hard deadline to hit for even large established companies, so it'll be interesting to see if Tesla can pull it off... As for Space X. Currently there are only 3 launch platforms to resupply the international space station. The Soyuz Russian system, the European Ariane system and the Flacon system by Space X. Given both the Soyuz and Ariane systems are backed by national government with decades of investment, Space X isn't doing badly....Rockets explode sometimes, it's what happens when your using a volatile fuel like hydrogen

Well, nearly close, Jaguar sold 462,678. Jaguar + Land Rover sold 462,678 cars, Jaguar sold only 81,000. So yes I was wrong http://www.jaguarlandrover.com/gl/en/investor-relations/news/2015/01/12/jaguar-land-rover-december-1415-sales/

BMW are hedging their bets and been very clever with their production road map. They pushing pure battery and fuel cell tech at the same time, but mainly focusing on better/cheaper carbon finer chassis production, which will benefit any future car regardless of power source. http://www.carmagazine.co.uk/spy-shots/bmw/bmw-i5i7-scoop-target-tesla-model-s/ Do your own research into hydrogen as a fuel source and your quickly see just how difficult it is to implement in real life. Hydrogen for fuel cell cars needed to be compressed to 10,000 PSI before it can be used. 10,000 PSI is ALOT of pressure, hence the hydrogen 'tanks' need to be made from kevlar. Don't forget hydrogen fuel cells also need platinum as a catalyst, so by nature is costly to mass produce. Toyota is reported to be making a LOSS on every Miria hydrogen fuel cell car it produces. Despite the Miria costing £53k AFTER a £15K government grant. Tesla on the other hand has a >25% profit margin on every car sold. Hyundai has sold barely 300 fuel cell cars in its first year of production....Why would you buy one, if you think charging battery EVs is a pain see if you can find out where your nearest public hydrogen fuel station is.....If your waiting for hydrogen fuel cell cars to replace ICE machines, than I agree, you will be waiting for a life-time. It's becoming very obvious to a lot people Toyota has backed the wrong technology. But having spent so much on researching hydrogen they cannot just back down - Especially not when Nissan down the road is been so bullish about battery EVs. But as I've said countless times before, it's going be a exciting few years to see how things develop.

Tesla just announced their Q2 sales figures....53% increase compared to last year, and about on track to hit 55,000 cars delivered this year. http://ir.teslamotors.com/releasedetail.cfm?releaseid=920434 Jaguar sold only 88,000 cars in 2014. I suspect with Tesla about to start deliveries of their SUV, which currently has 20,000+ of preorders, next year (2016), Tesla will be selling more cars than Jaguar. The Tesla Battery factory build is also ahead of schedule, and will start producing battery packs by June/July 2016. If Tesla can meet their target of delivering 500,000 cars by 2020, the likes of BMW/Audi/Merc will be looking over their shoulder very nervously - Which is why the VW group is determined to bring out a 'Tesla killer' machine before 2017. I don't know about you guys, but for me 2020 is not that far into the future

Completely off-topic: But some people have already created an AI that can play Atari video games better than any human, and now working on a version to play 3D games like Quake. This is talking about taking a bit of 'code', which start off with no understanding about how to play any game or it's rules, and than 'setting it loss' on a video game - and seeing happens. The scary bit is when the programer admits they had 'no idea the code would be able to develop 'longterm' memory, because they hadn't added in that bit of code', ie: The bit of 'code' developed in a way that was un-predicted by the programmers - Putting it in evolution terms, the code, 'evolved' and adapted it self to become better - That in my book is bordering on creep levels of AI, the ONLY things in nature that can adapt and evolve is living creatures

For commuting from A to B, I wish I had a drive less car for the last 18 months when I was doing 100 miles+ a day, and wasting 3hrs of life on the road. For 'fun', clearly not, but I don't see complete automation coming any time soon.....You would need a self aware AI for that kind of automation. Strangely though, whilst Google is busy developing smarter and deeper AI (Which is why the Google Search engine is so good, because it tries to 'understand' the meaning of a page, and question), all the brightest minds agree that a self-aware AI is closer than anyone one thinks, and when it does appear, we probably wouldn't know it, until it's too late. May just be a load of rubbish, but when Elon Musk, Bill Gates, Steven Hawkings all sign up and paid money into a research project to try and develop a 'friendly' AI, who knows....Tesla incidently has the most 'automated/robotised' production lines in the world....So instead making cars.... I would imagine it wouldn't take a super intelligent AI very long to work out how to mass produce these things instead....stick a M16 on that thing, and ummm...yes, well, you wouldn't have to pay £8 to go and watch the latest Terminator spin-off at the cinema....So your right, may be we shouldn't chase after progress just for the sake of it http://www.wired.com...rightest-minds/

I'm sure V12 wouldn't die, horse racing is as big industry as ever....As for driverless cars, we all know every car manufacture has been developing them long before EVs appeared. EVs will actually accelerate their appearance, simply because you have much better electronic throttle control with an electric motor than any ICE unit, so adjustments to power can be made much quicker.

this has been dicussed Its been skirted around as no one has an answer So where is the electric coming from and how much will it cost, less than a litre of fuel now to comparative mpg? No one has an answer because no one knows. Grid capacity is already a concern for energy companies without EVs. Hence the push for more and more renewable power generation. Like I've said, I didn't know a small solar panel on my house will actually generate all the electricity I'll ever need for domestic use - but you need to pair up the solar panel with a battery pack. If 20% of houses did this, suddenly your free up a lot of the strain on the grid. Equally I didn't know wind turbines are having to be turned off because they generate too much electricity at certain times.....Again battery technology to help 'smooth' out the inherent peaks/troughs in solar/wind energy sources will help. This is probably why Utility companies have bought up $800 million worth of Tesla 'Power-walls', from an energy company point of view, renewable sources such as wind and solar are cheap/free once set-up, so if they can make these renewable sources work better and start replacing coal/gas/nuclear power stations, they are in for a BIG jump in profits. After all wind/sun is 'free', unlike coal/gas/nuclear power stations which are very expensive to run....Let's just hope no-one from the government has been watching the Simpsons and come up with a 'sun' tax http://bgr.com/2015/05/08/tesla-powerpack-powerwall-battery-sales-estimate/ In the long-run, who knows, but that's part of the excitement As for absolute economy the Tesla P85D has an 'e' mpg of 88/84 - according to US measures, which is as good as it gets interms of accuracy. The Leaf 126/102 mpg = So the smaller, lighter, slower EV is more economical, nothing changes there compared with ICE cars.

So is this why virtually every car manufacture is putting turbos on their performance car (and normal family run-arounds). The GT86 was designed just for people who wanted NA, lightweight car + manual gear box....It was well priced, well buit...Now if that is what all 'petrol heads' want than it should have sold like hot-cakes....Instead everyone went mental and started raving on about a 4wd, turbocharged Golf, with 4 exhausts (really??) and fake engine noise just to cap it off. Forget for a minute all the discussion about costs etc, just consider what you actually want in a 'fast' car.....Manufactures spend stupid amounts of money developing ever more complex power trains to that they can deliver faster 0-60 times along with better economy - a 8 speed gear auto-box now becoming 'standard' is testament to that...But why on earth do you need 8 gears?? Because the Internal Combustion Engine (ICE) can only deliver optimum power in a very narrow power range, so without gears, your limited to a very low range of speeds. Than you have the issue of 'throttle lag', so as you press on the pedal and demand power, in order for that power to be generated, in an ICE engine you have to wait for the fuel pump to deliver more fuel to the combustion chamber, wait for the cylinder head to compress the fuel and air, wait for a spark to ignite, and finally wait for the resulting explosion to push the cylinder down and deliver motion.....All great and good, because that's what we are use too. So ICE drivetrains are hindered inherently by the need for gears, and throttle lag = This is physics you cannot get around it, hence the every more complex DGS/anti-lag systems. Now consider how an electric motor works - You don't need gears because power delivery and efficiency is pretty much 90% through out it's entire rev range - which goes from 1 - 140,000 (compared to ICE engine that at most delivery <20% energy efficiency in a 2000 rpm power band). When you ask for more power from an electric motor, electrical current flows into the conducting loops at higher rates, and the electromagnetic forces generated causes motion. So the rate at which power can increase (ie: Acceleration) is limited only by how quickly you can move charge from the battery to the motor.....Last time I checked electrical charges moves at the speed of light in perfect vacuum so your loss some speed in air ....But essentially the speed at which an electric motor can deliver max power is limited by how fast you can smash the throttle with your foot I appreciate the need for noise and drama, after all people still spend millions on horse racing, that does nothing for me, but people love it....Though I can imagine riding a horse at 40mph is probably a lot more exciting than driving any V12 at any speed. For some people they will always want noise/drama, which is fine, but for the majority I suspect an EV that can deliver more performance than an ICE car, for 1/10 the running costs will be a much more tempting preposition. What will motor-sport look like in the future?? I have no idea, but I can tell you I enjoyed playing Wipeout just as much as any driving sim. Remember the current EV are only generation 1 devices (Like the original iPhone). If Tesla a company that has little history in car building can already mass produce a 691bhp EV saloon, just 12 years after the company was founded, what on earth are they going come out with over the next 5 - 10 year.....Aside from MageLev trains, the current fastest high speed trains in the world are powered by Electric motors - The current output of these things stand at 12,900 BHP ICE powered diesel trains cannot anywhere near that kind of power-output. https://en.wikipedia...ailways_CRH380A The hinderance to EV motivation is power source - Which is why hydrogen fuel cell cars were seen as answer for a long time (These are still electric cars). BUT with the advent of cheaper and more powerful batteries, battery EVs cars have the potential to deliver performance figures no ICE powered machine can dream off. Apparently Tesla have pushed their machines to figures far above the quoted 691bhp, but aren't yet ready to deploy it in the market. It wouldn't surprise me if Tesla comes out with a 1000bhp machine just to aggravate Bugatti, the P85D came about because Elon Musk wanted his daily car to accelerate to 60mph just as quickly as his McLaren F1....So the 691bhp Model was just a side project - not a bad outcome I would say Rather than worry about the survival of V12 which only a minority of people are interested in (ie: members on 350z forums ), perhaps what we should be more worried about is how the 'mass public' whom upuntill now had access to 'fast' cars limited due to running costs/noise/lack of interest, will behave when give SO MUCH power. I suspect most of us on the forum have gone from lower power cars up to higher power machines, and I hope most of us here have a healthy respect of when/where to use excess power on public roads, and know the consequences.....BUT average Joe blogs whom upuntill how is use to thrashing a 2.0 TDI A3 whilst following you with-in 1 inch of your rear bumper because they have no real interest in cars, and think they can stop in 1 meter at 70 mph....Do you really want these guys behind a silent 691bhp machine ... This video sums it up, look the reaction of the guy on the delivery scooter 50 seconds in, his pulling out just after the P85D has gone full throttle in a pedestrian/built up area....If you did that in a V12 Lambo etc, all the noise/drama will attract so much attention people will know your about to behave like a T***T. But in a P85D, hardly anyone turns a head, until your about smash into them at 60mph+, the comment from the guy sitting in the front seat 'why do people buy Ferrari's' sums up my concerns. 691bhp in the hands of a guy who doesn't understand why people buy Ferrari's ... I'm amazed there hasn't been some horrendous accident in the states yet involving a P85D, but sooner or later it'll come, and than we'll have a new law to govern the max power-out put of EVs in some zone, a bit like the 'temporary' national speed limit that was set up after a few people went to fast on the M1 when it first opened

That's the kind of progressive spirit/mindset we need more of, there are still tribes in the Amazon rainforest that have followed your guidance, you could argue they have done the right thing and made the right lifestyle choices

That's the beauty of the electric motor, energy is transformed to motion via the magic of electromagnetic forces, there's no need for complicated combustion. Electric motors are 80-90% efficient at covering energy to motive force, compared to 17% go the best ICE engine. Electricity generation is a problem that needs to be addressed, but I certainly didn't realise a solar panel with 20% efficiency (current mass market panels) can supple enough electricity to power my house when combined with a battery pack (excluding car charging). As for people who don't think things will change for another 100 years....When I was at school the 'internet' barely existed, we had this thing called Netscape. Look at where we are now with communication.... This is what an aeroplane looked like in 1915... ....and this is what we have managed to build now. Personally I find it sad to think people here don't believe we can transfer from petrol cars to EVs in the our life time. I see/talk to people everyday whom have lived through TWO world wars, I cannot imagine what they think of the world now compared to when they were growing up.

It's mostly 'inspections' - I wonder how that compares with the service schedule of any M car

Ofcourse been an American company you have to be sure to read the small print, but I've never seen any other car manufacture state anything like this on their website....So either Tesla have very good lawyers or are confident about failure rates. I suspect it's a bit of both

Utter bobbins. Of course there's things to service! Please don't tell me that EV owners in general (not you, I'm sure you wouldn't as you're not daft) genuinely believe that they can buy one of these things and never worry about taking it to a garage for an annual look over? I can't believe people that buy these would be home mechanics either, as a rule. What do you want to service??? There is no oil to change, no filters, brakes wear slowly due to regen. Even the 'coolant' doesn't require changing on the Leaf till 125k. Electric motors theses days are probably one of the most reliable appliances around, so unlike turbo charged ICE units which we all know are 'sensitive' at the best of times. Yes suspension/tyres wear, but you hardly need to 'service' one to anywhere near the same degree as any ICE car.

I'm not preaching to anyone... The reason I started looking at EVs is because I wanted something faster (and more reliable) than my 360bhp+ BMW 335i. On the shopping list were things like the XJR supersport and F10 M5's....But although I can stomach £50k of a used car I cannot justify £1k/month on going running costs on fuel/servicing/warranties etc Hence when I saw you could get a 400bhp EV saloon with 300 mile range that costs under £10 to fuel I was interested.... Regarding EV costs, a 691bhp P85D starts at £79k, this is actually cheaper/same figure as a 500bhp+ super saloon from BMW/Merc. On reliability Tesla give you a 8 year unlimited miles drivetrain warranty new, which is far more than any ICE car, and you don't even have to service the thing!!...mainly because there is nothing to service. Even a used Tesla S bought from Tesla comes with a 4 year, 50,000 mile warranty, again far more than the normal 1 year warranty you get from BMW/Merc. The Leaf was a 'impulse' buy. I saw a thread on Pistonheads, did the numbers and realised selling the BMW now, will get me into a Tesla far quicker. My Leaf is essentially on a lease hire contract, which equates to £260/month ALL In (That's everything, insurance, servicing and deposit etc). You find there are hardly any ICE hatchbacks for similar costs - Most require at least 6 month deposit, my Leaf deal was ZERO (0) deposit. My logic was quite simple, if I really hated the Leaf it would just be cheap way to save money for 2 years, but as it turns out I love the EV drivetrain much more than I thought, and though it's saving me money now, it's tempting me more and more just to go for the 691 BHP Model S rather than the 'normal' 400 BHP version... I genuinely believe EVs will become mainstream much quicker than people think. Unlike the fabled 'hydrogen fuel cell' car, battery EVs are making real progress and with the exception of Toyota most car manufacturers are investing heavily in the technology. I appreciate all the sceptics and doubters, but if I've yet to see anyone actually complaining about how EVs drive....Reviewers moan about charging infurstruce, but that number is growing quickly. There are now over 3000 charging locations in the UK, and the numbers are increasing. https://www.zap-map.com/statistics/ Local councils are running EV buses, one even caught on fire recently ... http://www.bbc.co.uk/news/uk-england-york-north-yorkshire-33273548 All the predictions about horrendous battery degradation, not been able to lower costs etc are simply not true, Taxi companies are seeing useful range even after 100k. Every one is an adult here and can make up their own minds, but I get the feeling a lot of people have so many pre-held misconceptions about EVs that it's something they might not even consider looking at the details of one, regardless how much sense it makes....But again if we all just focussed on making rational decisions we'll all be driving £500 bangers The only point I'm making with these threads is the fact I personally am loving EV ownership, even with the limited range/power of the Leaf, it's convinced me the future of the ICE as form of motivation is well and truly limited.

So in the last few days there's been a flurry of rumours/news about battery development. Whilst it's true it took Lithium-ion batteries 20 years+ to come to market, with the stakes so high, new Lithium-sulphur and cheaper/more dense Lithium-Ion barriers appear to be developed at immense rates by lots of different people.... I'll be amazed if by 2020 VW/Nissan/GM don't all have a 200-300 mile range EV, in family hatchback form, that costs the same/less than an equivalent ICE car. I appreciate some people cannot see the potential of EVs and look past the current generation of EVs on the road, but I was a betting man I would go and buy a shed load of Tesla/Nissan/GM stock now....But I'm not so, instead I'll just keep watching from the sideline, and try to decided the best time to jump in and commit some proper cash into an EV (The Leaf finance is so cheap it's almost a negligible financial cost). https://cleantechnic...sts-reportedly/ http://www.autocar.c...ry-breakthrough

My wife is very pleased with the IS - worth the price tag, I've tried to convince her to swap it for Tesla Model S....She told me where to go....She's probably the only one on earth I wouldn't try to convince about EVs We'll be keeping ours a long while yet, at-least with these hybrids there are no modding options, so nothing for me to waste money on

You asked the question....Here's your answer....Though depending on your definition of 'lifetime' you might never see on a road near you

The IS is really good for covering long distances in comfort, our has adaptive cruise control/emergency braking so on the M-ways you literally don't have to do anything but the occasional steering input, spent 3 hrs a few weekends ago covering some 80 miles of the M1 and than 40 miles been stuck in London rush hour traffic, didn't even feel tired at the end, to top it off it the mpg computer was reading close to 70!! But the delay between you pressing throttle and the car shifting isn't great when your really trying to push on, but it's not that type of car...If you want to feel an EV motor shoving you along at full power from 0 rpm, your need to try a proper EV...But there's a thread on that already

There's a trial route of EV buses in MK using wireless charging. http://www.mkweb.co....tail/story.html BMW is also using in their i8 Forumla E safety car, and working on a commercial version. http://gas2.org/2015...ss-ev-charging/ Problem with wireless charging is you loss 'some' efficiency. By all accounts the efficiency of power transfer from your house/grid to an EV battery via a wire is close to 98% efficiency. Wireless charging is currently around 90%, it may not sound like much, but over time thats a big loss in efficency. Surprisingly the plug-in part of the Leaf is so easy, its no harder than plugging in your smart phone. I don't think you necessary need wireless charging, what you need is FASTER charging to cover long trips. Tesla superchargers can already deliver 170 miles or range per 30 minutes of charge, Tesla have just introduced a new liquid cooled cable, and rumours have it they are targeting 100 miles of range per 10 minute of charge...Which is getting closer to conventional ICE fueling rates. http://www.greencarr...rging-even-more The VW/Audi group are fully committed to EV development, the top guy at Porsche is directly targeting Tesla...So an hybrid/electric 911 will be coming... “Tesla has built an exceptional car. They have a very pragmatic approach and set the standard, where we have to follow up now.†http://insideevs.com...rd-must-follow/ Toyota on the other hand are trying to raise $4 billion additional investment in hydrogen fuel cell car production, so like it or not there is a whole raft of changes in the automotive industry, what we are seeing now are early generation one machines, the days of the ICE are numbered - certainly in its current form as a main source of motivation, there may well be a role for ICE to act as 'generators' for range-extender EVs....and I for one cannot wait to see what's coming down the line for me to spend my money on In regards to electricity generation, on our next house I fully intend on getting a 4 KW solar array and partner it with a home battery storage - probably at least 10 kWh. Excluding car charging, we use about 10 kWh of electricity per day, from what I understand even here in sunny uk, a 4 KW solar system can generate over 3600 kWh over a year, so essentially that's your entire years electric energy needs met by using solar panels. Money-wise, this doesn't make sense, I make no pretences, the reason I want to go down the solar panel battery route is because I want to explore if it possible to go completely 'off' grid, so I'm willing to pay extra...But solar panel technology is also developing at a rapid rate, so who knows, it may become possible to even charge your car off solar energy alone.