Tow cars: the hybrid questions

[KeefySher]

Hello Ray,

I know this might seem like nit picking but, "quality control" is what the caravan industry try to apply now, and most of the time it fails.

That is because they try to inspect quality in to the products rather than build with quality in mind.

For example; a careless Baker will rapidly go out of business if the bread they make turns out poorly, the only quality test is what is end product like. This is in essence conventional "Quality Control by end inspection" and it's too late in the process, and it means that all the preceding work has been wasted, so the pressure is on in the caravan industry to release goods that are arguably not of merchantable quality.

By comparison, you will find that all successful Bakers apply "Quality Assurance" and will choose very carefully and have assurances from their suppliers about the the quality of the ingredients supplied. Recipes will be clearly displayed and followed, Their measuring equipment will be calibrated so exactly the right amount of ingredient is used. The mixing will be timed, ovens will be calibrated and have close temperature control for both proving and finally baking.

If you know your raw materials are good, and you control and apply the correct procedures to manipulate them, you will have confidence that your end product will be consistent. This means product is right first time, there is significantly reduced scrap and rework = lower manufacturing costs. and fewer unhappy customers!

Really ?

Having recently been awarded a prestigious contract by one of the major suppliers to the Caravan, Motorhome and Marine industry, I’m afraid I can’t just ignore that nonsense. If fact, I would go so far as to say I find it offensive.

We won the contract after months and months of hard effort and collaboration in response to the unprecedented due diligence of our client, particularly with regards to quality and consistency.

In particular, I quote ...

“By comparison, you will find that all successful Bakers apply "Quality Assurance" and will choose very carefully and have assurances from their suppliers about the the quality of the ingredients supplied.“

I would suggest that you stick to the baking, an industry which you clearly see as exemplary, but if you really are interested in learning more about the kind of rigorous quality assurance and consistency that today’s key suppliers to the caravan and motorhome industry demand, then please feel free to send me a message Prof, and I’ll happily enlighten you with real world facts and figures from 2017.

Perhaps this may even help to change your jaded view from yesteryear ?

Understanding who the businesses in your statement are would add credence to your words. Otherwise it's just marketing baloney. Can't be commercially sensitive either. If you are that good your products will readily withstand scrutiny, unless there is something to hide. Or are those parts the ones that you don't need to warrant as they are easily fixable on a leisure break by the DIY caravan owner who doesn't have to worry about throwing £20k+ at a caravan and has no expectation of it working first time every time?

Identifying the products would go a considerable way toward instilling confidence in future buyers of caravans. Conversely future performance of those products can be monitored via forums to determine if the trumpeting meets the reality.

Of the 25+ faults on our flagship caravan, those that were beyond my DIY abilities to fix (not that I would nor should have to be fixing whilst on a leisure break) were several bought in parts and sub assemblies involving basic manufacturing faults such as dry joints on PCBs, non existence of heat sink paste on heater unit, battery locker door failed assembly, mechanical sub assemblies not assembled. All those suppliers, of which some trumpet "World Class', 'Quality Assured', 'ISO 9001' etc in their marketing blurb failed at the first hurdle.

A slight hole in your quality argument is CoQ and what parameter CoQ becomes key. At present there appears too much fat in the caravan industry to even see CoQ on the horizon with the Hubble Telescope :evil:

 

[Angelfire]

Correct, we are doomed. My hybrid Mitsubishi PHEV tows at 17.1 per gallon, which is pretty abysmal. As for the electric side, 10/15 miles towing and the battery is dead flat. Here is the rub, because the car is towing the van, turning on the generator is just not viable, it will NOT charge the battery, I assume because the car is designed to run on electric, all that is generated goes towards running the two electric motors.
The battery is only viable for 5 years, then a new one is required at a cost of £5k I am informed. Then of course all these so called electric vehicles require electric to run, increasing demand and the pollution to make it. I imagine the cost of making the battery is fairly substantial, and also the cost of recycling it at the end of its life.
Here is a bold statement to make at the end of my post. As we march into 2018, I suggest that a half decent diesel will cost less to run and tow better than any hybrid/electric or a petrol engined car.

 

[ProfJohnL]

Hello Angelfire, and a belated welcome to the forum.

I agree if you are only getting 17.1 mpg towing economy the Outlander PHEV is particularly poor. Sadly this is actually surprising because unlike some other PHEV hybrids the Outlander does not use an Atkinson cycle engine for its generator but the more conventional Otto cycle engine common in most cars, so one wold hope it would give similar towing mpg to petrol driven versions or vehicles of similar size.

As for battery life, there is a lot of evidence that suggesting motive power batteries are lasting for longer than was predicted, so 5 years may be being pessimistic.

 

[Parksy]

Hello Angelfire, and a belated welcome to the forum.

I agree if you are only getting 17.1 mpg towing economy the Outlander PHEV is particularly poor. Sadly this is actually surprising because unlike some other PHEV hybrids the Outlander does not use an Atkinson cycle engine for its generator but the more conventional Otto cycle engine common in most cars, so one wold hope it would give similar towing mpg to petrol driven versions or vehicles of similar size.

As for battery life, there is a lot of evidence that suggesting motive power batteries are lasting for longer than was predicted, so 5 years may be being pessimistic.

Around 17mpg would be about right for a petrol version of the Outlander, Prof.
My old 2.8td Pajero Trundle Truck only returned between 22-25mpg when towing, which is why I eventually replaced it with a 2.5td Kia Sorento.
The Outlander PHEV unfortunately only has a 1500kg towing capacity, so to my mind a touring caravan owner would be no worse off if they bought a towing vehicle with a smaller engine capacity with a towing capacity closer to the reduced engine size. There's a review from David Motton of the Outlander PHEV Here

 

[otherclive]

I’m not surprised that the Outlander has a poor towing consumption given the cars weight and that the petrol engine is low power/torque. I had a 2014 Forester with the 2.0 non turbo petrol 150 bhp engine and around 200kg less kerb weight than the Outlander. It wasn’t bought as a tow car but I thought I would give it a try towing a 1300 MTPLM caravan. But whilst it was stable the engine just needed too many revs to make normal road progress. Fuel consumption when towing would be 20-22 mpg. It was a lovely car solo but I couldn’t live with the unrelaxed towing performance. So your Outlander consumption is where I would expect it to be. I guess that looking at the whole picture it’s necessary to consider annual towing mileage against total solo mileage. Must admit to being a bit surprised at the PC test with nearly 25mpg when towing on petrol. Big difference to your figures.
WHICH did a recent survey and were hard pressed to find evidence of battery failures or reduced performance such that they expect batteries to go beyond the warranty period. US government agency surveys and research supports this too.

 

[Dustydog]

My friends Lexus rh450 hybrid uses a 3.5 Atkinson cycle petrol engine. His consumption is poor. PCv last year tested the new Volvo XC90 hybrid. It managed 16.1 mpg when towing.
Until electric vehicles are the norm I hope diesel development continues to improve
mpg and pollution output.

 

[Bid]

We have owned a Outlander phev for over a year now. Most of our driving is around our town, about 8000 miles all on electric the cost of which is far less than our last diesel car. We tow a small caravan within the 1500kg towing capacity of the Outlander and during the year just finished did about 4000 miles. According to the onboard computer the car returns 24/25 mpgand has never dropped anywhere close to the 17.1 mpg quoted the another post. Maybe it’s all down to driving style? I have chatted to other Outlander phev owners who tow and as far as I can recall said there car returned between 20 and 25 mpg. Yes our old diesel did more than the Outlander.

The Outlander suites our way of life and does a good job for us.

 

[ProfJohnL]

Hello Bid,

Thank you for your comment. I think you may well be right, and that is why I suspect it is to do with the surprising torque that is available, and there is a big temptation to use it, but of course this is going to hammer both the battery charge and the fuel economy.

I have frequently advocated that we may need to change our driving habbits to make best use of the new technology, It looks as though you mah have adapted more successfully than others.

 

[Craigyoung]

I agree with the prof , you put your foot down on any car and your mpg statistics are going to go down. My driving has significantly changed in the last 5 years as we got a thing called GreenRoad put on the buses( it's a similar thing that young drivers now get on their cars when they first pass their test for insurance reasons) which monitors your driving , acceleration cornering, braking and your manner of driving and even since getting that on the buses , me driving my cars has made a massive difference in my driving even the wife telling me I'm driving to slow now but I'm never in a hurry now , there's enough idiots on the road as there is !!

 

[ProfJohnL]

I was thinking about how to show this effect, and I concluded that it could probably be demonstrated fairly easily:

Many car manufacturers produce one or more models where the engine size and fuel are the same but the engine is tuned differently. Just for example my VW Passatt 2L diesel was available with a 140BHP or 170BHP engine varient.

Assuming all the other factors were the same (weight, Tyres and gear box etc) in principle for the same road conditions and speeds the cars should both need identical power (and fuel) requirements.

Ask a driver to take the two cars on the same journey and it is most likely the more powerful version would use more fuel. principally because the of teh cars better acceleration would be used which will consume more fuel.

I know this is not directly related but it does show that even those similar conditions may apply to each vehicle, external affects can adversely affect fuel consumption. It also made me think about a phenomenon that became widely recognised during the war where convoys of vehicles would often be used.

It was noted that even if the lead vehicle maintained a very steady speed, the vehicles at the tail often needed to vary their speed quite a lot to keep up.

The effect arises because in principle every one tries to maintain a nominal distance to the vehicle in front, but we are incapable of such accuracy, so the first gap will vary a bit, and that means the second vehicle will not be maintaining a constant speed, as it slows the gap behind will reduce and the third vehicle will need to slow even more to try an maintain the gap. The converse is also true and if the gap lengthens the following vehicle will speed up to close

Each time this happens the effect on the vehicle behind is amplified slightly, The longer the convoy the grater the effect becomes, and ultimate there comes point where the tail of the convoy can be virtually stopping and then having to accelerate significantly above the speed of the lead vehicle.

Consequently following vehicle's fuel consumption is usually higher than the lead vehicle, and in long convoys the tail vehicles may be using almost twice as much.