|595 forum posts|
Testers aren't expensive - **LINK**
|J Hancock||20/12/2018 13:13:59|
|297 forum posts|
Back to 'efficiency'.
How can it be possible for a 'hybrid' car ( Prius say ) to be more 'efficient' than a ' non-hybrid' version
of the same car ?
|not done it yet||20/12/2018 15:27:14|
|3145 forum posts|
They make neither an electric only nor a ICE version, so not a good example to discuss?
Internal combustion engines are not much better than 25% efficient? Excluding very large diesels, here.
An electric motor is likely better than 90% efficient.
|Neil Wyatt||20/12/2018 15:38:28|
16248 forum posts
The electricity does a lot of the heavy lifting, like accelerating and round town stop-start driving when the petrol engine is least efficient.
I recall they were invented by Fredrick Porsche in about 1904?
|J Hancock||20/12/2018 19:21:34|
|297 forum posts|
Thanks for explanation, can (just about ) get my head round how that works out from a thermal efficiency
|605 forum posts|
|Clive Hartland||20/12/2018 23:07:20|
2455 forum posts
I did read that the Hybrid cars that were meant to be charged and driven short distance were in fact being drive only on the petrol engine, mainly due to lack of charging facilities. Also the long waits to get them charged.
I cannot see yet these leccie cars being a viable means of transport where you spend more time charging than driving
|Michael Gilligan||20/12/2018 23:51:03|
13547 forum posts
They are working on that, Clive **LINK**
Heaven only knows what the infrastructure would cost though
|Bill Phinn||21/12/2018 00:00:30|
|185 forum posts|
One of the other acknowledged obstacles at the moment to the widespread use of electric vehicles is the difficulty many users have charging their vehicles.
Yes, many people have a driveway or garage where they can charge overnight, many work at a location that can provide staff parking and charging points, but many people do not fall into either category, so where/how are they going to charge their vehicles with dependable regularity?
Having charging points on the street outside people's homes is the usual suggested solution, but what happens when you have people with electric vehicles and conventional vehicles both competing for limited parking spaces on the same street? If the driver of a conventional vehicle is excluded all of a sudden from parking in any vacant space equipped with a charger, will drivers of electric vehicles be similarly excluded from parking in spaces that don't have chargers, or will they get preferential treatment? Either way, how do we fairly apportion the availability of spaces of each kind?
I accept there are worse problems in the world needing a solution, but I can see a certain amount of injustice on the horizon, and, on the principle that nothing tends to stand in the way of "progress", I suspect it will be drivers of conventional cars, not the drivers of electric/autonomous cars, who will find themselves on the receiving end of it.
|pgk pgk||21/12/2018 07:21:21|
|1396 forum posts|
From the practical viewpoint Tesla leads the way on leccy cars but will be overtaken when the big boys finally get their acts together. Home charging on 240v with a dedicated charger and I can pump 20-22 miles range into the battery per hour It's possible to charger using a 13amp extension lead but then we're down to 2-3 miles range per hour of charge. ( a llghter smaller battery car will get a longer range per hour but less total range).
Tesla superchargers still lead the way on high charge rates but they are spread a little thin in the UK at the moment. They'll pump in as high a 120KW in optimum conditions but due to the needs of balancing the charge, getting battery packs to optimum charge temperatures etc - well it'll manage to go from 20%->80% charge (on a 100KW pack) in 30-35mins adding a theoretical 160 miles range. BUT temperatures make a huge difference. My theoretical 300 mile range is clobbered in frosty days down to around 200miles by needing to heat the battery and the occupants. On the other hand with the needs to balance when the battery gets over 70% full the charge time from 5% to full 100KW would be pushing towards 90mins+
Charging issues revolve around the usual lack of leadership. There's heaps of charging stations available but mostly in dribs and drabs of 1-2 points and run by dozens of operators often needing membership and rf cards etc to get access.... whereas simply sticking a credit card into the thing would liberate the motorist to a bigger number of options. But then there;s the leccy cost which varies from free with monthly membership to free with local support (scotland and Ireland) to cheaper if using ecotricity and an ecotricity customer (15p / KWh) to higher (non ecotricity customer 30p/KWh). There's also the differing charge port types and speeds - anything from bog slow 3KWh to 50KWh on the rapids - still way slower than the Tesla network.
Those of us with a deal for free supercharging for life of ownership will grab any opportunity to top up free but that promotion has gone and Tesla charge a not unreasonable 20p/KWh.
With the release of the new Model3 the US has seen a surge in ownershp and that's leading to queues at chargers.. again Tesla usually put in several when they do (8+ usually) but I've been to a motorway services and seen 7 out of 8 occupied and that's before the Model3 sales start UK.
All new EU cars (it'll go global) will have to have GPS tracking and that inevitably means road pricing since it;s harder to tax car electricity when home/work charging used - it'll be a double whammy of higher electricty costs (spun to explain the need to modernise the network and pay for chargers and 'encourage' housholds to use less) and the road usage tax.
|J Hancock||21/12/2018 07:38:25|
|297 forum posts|
If 'efficiency' had ever had any credence, then the saturation of our roads by 'cars' and ' lorries' would never have been allowed to happen.
Rail, or water, or lighter than air transport would be the way to have proceeded.
Unfortunately, there was an easy tax income using any form of fossil fuel.
That revenue from 'electric charging' of cars is missing , at the moment. It won't last.
|martin perman||21/12/2018 08:47:13|
1614 forum posts
I run a 4 x 4 diesel estate for several reasons, economy, I have to get my wifes mobility scooter in the back but the main reason is my hobby, I attend steam rally's with my stationary engines so need to tow a trailer and having a 4 x 4 gives me a better chance of moving around on wet fields, I dont see an electric vehicle, that I can afford, that would be capable of my needs because most of my battery usage would go getting out of fields and pulling up to 1.5 tons.
A van would be of no use because we are a one vehicle household and my wife cant get in one because of her medical problems.
|not done it yet||21/12/2018 12:04:06|
|3145 forum posts|
First para - it is a simple way to beat the city bans on fossil fuel only vehicles. Tax incentives meant that these vehicles were cheaper for a company to run, than an equivalent company car with ICE. Likely the london congestion charges have been waived/reduced for such vehicles. Nothing to do wit charging facilities.
Second para - do wake up! Some will go hundreds of miles without needing to charge and most can be charged sufficiently, for the average motorist, overnight. Just look up the range specs for a Hyundai Kona! Easy 250 mile range and fast charging possible. Who often wants to drive further without a half hour, or so, break?
I, for one, don’t believe all that I read!
|Nigel McBurney 1||22/12/2018 10:41:41|
579 forum posts
I have the same hobby as Martin Perman and need 4 wheel drive to tow a trailer plus up to 3/4 ton of engine on wet rally fields ,and when I had a 6 inch Burrell there was close to 31/4 tonnes on the back hook, which a Discovery 4 took in its stride though its expensive to buy and run ,and comfortable but with too many electronics to go wrong and AA relay membership essential,though my wife stated that she would not come to shows unless we bought a new Discovery,(a nisasan x trail was an awful tow vehicle, If I lived in Aus or other foreign partsI would pay the extra for a Toyota s reliability.I started on the roads on motor cycles (a reliable Greeves Scottish with its super rubber front suspension remember those) and then bought an1950 A40 Devon pick up ,(to carry the trials bike to events further afield)oh happy days, that Austin handbook stated lubricate the suspension every 500 miles !! In those days one learnt to be able to use the spanners,understand how it worked, and carry lots of tools plus spare plugs,points,condenser ,tape wire and string, This gaining of knowledge and the ability to get home after minor breakdowns taught mine and earlier generations a certain mechanical abilty which allowed us to tackle poblems and repair on household and other items, Nowadays vehicles are far more reliable,and items which do go wrong are difficult to diagnose and repair without some computer input, but later generations never had the chance to learn on simpler less efficient mechanics and nowaday do not have a clue how to tackle anything other than a keyboard.So whats the point of making household items repairable An awful lot of people cannot change a wheel,Oh I forgot cars dont have spare wheels now!! ( mine Do) and the trailer.Though modern vehicles are far more reliable, I have found that my old mk 1 range rover was a far better off road vehicle than my discovery with its crap electronic controls which are supposed to improve traction but dont.
Please login to post a reply.
Want the latest issue of Model Engineer or Model Engineers' Workshop? Use our magazine locator links to find your nearest stockist!
You can contact us by phone, mail or email about the magazines including becoming a contributor, submitting reader's letters or making queries about articles. You can also get in touch about this website, advertising or other general issues.
Click THIS LINK for full contact details.
For subscription issues please see THIS LINK.