Help me to decide if paying almost £1000 for a diesel hob in my van is a good (MSE) investment

Andy_L

GervisLooper said:

Andy_L said:

ThisIsWeird said:

Andy_L said:

To me burning fuel to heat up a ceramic hob to then heat pans of food seems very inefficient compared to just burning the fuel & using that flame directly to heat up the pans

It might not be as efficient at transferring the heat - I don't know - but the bigger picture here is overall running costs, and here diesel seemingly wins hands-down.

Electric heating is a lot more efficient than gas - pretty much 100% eff - but still a lot more costly.

And then add the room-saving and convenience.

I'm mean using the diesel (or other liquid fuel) in a stove directly rather than comparing this gadget to a gas burning stove 

Are you suggesting using a highly volatile liquid fuel inside of the campervan, because this type of stove mentione in the OP does not have any open flame, that is why they are seen as safer generally even than gas stoves? I guess you are thinking of coleman type pressure stoves which are used for camping which can run on petrol or diesel at a push. My mum happened to have one in the garage which I was testing in the garden and I found it pretty volatile and found quite a few things could go wrong with them causing possibly dangerous outcomes. That is talking about using them outside let alone indoors.

I want to cook inside the van, that is important to me which liquid stoves do not seem safe to do with, especially in a tiny transit connect. I did pitch that idea to people online initially, thinking it would be much cheaper and simpler, and they almost unanimously said it would be idiotic to do.

Its more an observation on the inefficiency of the combihob. At 10 minutes to boil (possibly more - that time may be assuming the stove is already warmed up) thats worse than just a simple trangia-type alcohol burner, stoves that are noted for being inefficient (but the advantage of cheap & easy)

Andy_L

GervisLooper said:

Some people mention it would take a decade or more to "pay it off" but that is misleading imo. I will be paying to cook meals one way or the other so it doesnt matter what it costs in isolation. If I didnt buy this it isnt like I would just live for free on fumes from the atmosphere otherwise. So I would be using another fuel source, which costs money, most likely gas. So that is what it should be compared against.

QrizB said:

GervisLooper said:

Gas I worked out costs around £312 per year for using it to cook one hour per day average. I worked this out as I pay around £2 per 220g gas cartridge for a camping stove and they last me about 3 cooks at an hour a day.

So, with gas, you're using 70g (0.07kg) an hour, 67p a day.

A kilogram of gas contains about 12kWh/kg, so 0.07kg is 900 watt-hours. If you use that in an hour, that's an average of 900 watts - which is within the typical range for a single, small gas burner.

Andy_L said:

Its £28 for 6kg of propane, not £40 (so ~1/2 the price of the 220g bottles) ETA:  which will make a big difference to your break-even calculation
https://www.calor.co.uk/lpg-prices

That's £4.67 per kg, so 70g would cost 33p.

GervisLooper said:

Lpg is cheaper than normal gas at average 80p per litre going off memory ...

A litre of LPG is half a kg, so LPG is £1.60 per kg. 70g would cost 11p.

GervisLooper said:

£1.62 is the price of 1 litre of diesel.

The appliance states that it will consume, at maximum, 0.27 litres per hour of diesel during operation.

But you won't be running it flat out all the time. I would expect you to be running it at 900 watts, ish, the same as your gas stove.

A litre of diesel contains about 10kWh. Running a burner at 900 watts for an hour would use 90ml (0.09 litres) of diesel. If diesel costs £1.62 a litre, 90ml will cost 15p.

To summarise:

On an equivalent energy basis, your cooking costs will be:

• 220g gas cartridges: 67p a day.
• 6kg propane: 33p per day.
• Bulk autogas: 11p per day.
• Diesel: 15p per day.

Compared to 220g cartridges, diesel would save you 52p/day, £190 a year.

Compared to 6kg propane, the saving is 18p a day, £66 a year.

Autogas is 4p/day, £15/yr, cheaper than diesel, which can probably be ignored.

and QrizB's numbers let you do that - 52p a day saving over your current set up. Although I'd disagree with their assumption that "you won't be running it flat out all the time" I suspect that cooking is when you run it flat out & its when its in "heating mode" that it drops to just ticking over

GervisLooper

Andy_L said:

Its £28 for 6kg of propane, not £40 (so ~1/2 the price of the 220g bottles) ETA:  which will make a big difference to your break-even calculation

https://www.calor.co.uk/lpg-prices

It may say that on the site but places where you can actually buy it, resellers, where you go and pick it up, from my research the prices are around £40.

A couple more £35 odd yea.

https://www.adamsgas.co.uk/product/calor-gas-propane-6kg-refill/

GervisLooper

I received a warning this morning to stay away from diesel and go with lpg because

Regardless of ecological effects, you should really convert to LPG because desiel fumes are significantly worse for your health. They lower your IQ significantly, cause cancer, heart disease, increase birth defects/impotency, and a litany of other issues. It very likely permenantly damages your DNA, at some level, at any amount of exposure. Stay away from desiel fumes.

If you are using the disel while parked, I would think you are exposing yourself to significantly worse air pollution than if you are driving. If you can smell it, you are in danger.

Definitely do NOT use wood instead as a source for heat. The particulate and PAHs that are produced in its smoke are just about as dangerous. Studies show that heating your house with wood is roughly as dangerous as a 1-2 pack a day smoking habbit.

Thoughts? The person who wrote it seems to have a chemistry background from their other posts which is what made me take notice.

ThisIsWeird

Whilst all of that is most likely technically correct, in the overall scheme of this being a small heater sitting inside a large-engined diesel van, there should be an undetectable additional risk.
Even without your wee hob running, you will be breathing in diesel and other traffic fumes from the air, especially if you are parked on your folk's driveway and are not 'wild' camping.
Diesel vehicle pollutants are not good, this we can agree on. But your wee heater will not make a jot of difference.
Do the specs indicate its burner efficiency? The components and %-ages of the exhaust gases?
And, of course, you should ensure that the exhaust is vented away safely from your van. Not sure which way is best - is there a high level flue?
The 2018 diesel minibus I regularly drive came fitted with a wee diesel heater in the rear, which from a perfunctory look appears to vent out under the floor via a smallish bore nozzle. Not that I've ever turned it on - the yoof can freeze, as they already sing too loudly - but I'd have zero concerns about this wee heater contributing anything detectable to the surrounding pollution. 
It's all relative, and that wee heater produces relatively nothing.
That's my take.
Due to that unit's significant size savings, ease of use, neatness, reduction in internal moisture production, low running costs, and - very importantly - its dual-use, I would personally be very tempted to have one.
Unless a significant drawback was found - but pollutants don't appear to be one of them.

GervisLooper

ThisIsWeird said:

Whilst all of that is most likely technically correct, in the overall scheme of this being a small heater sitting inside a large-engined diesel van, there should be an undetectable additional risk.
Even without your wee hob running, you will be breathing in diesel and other traffic fumes from the air, especially if you are parked on your folk's driveway and are not 'wild' camping.
Diesel vehicle pollutants are not good, this we can agree on. But your wee heater will not make a jot of difference.
Do the specs indicate its burner efficiency? The components and %-ages of the exhaust gases?
And, of course, you should ensure that the exhaust is vented away safely from your van. Not sure which way is best - is there a high level flue?
The 2018 diesel minibus I regularly drive came fitted with a wee diesel heater in the rear, which from a perfunctory look appears to vent out under the floor via a smallish bore nozzle. Not that I've ever turned it on - the yoof can freeze, as they already sing too loudly - but I'd have zero concerns about this wee heater contributing anything detectable to the surrounding pollution. 
It's all relative, and that wee heater produces relatively nothing.
That's my take.
Due to that unit's significant size savings, ease of use, neatness, reduction in internal moisture production, low running costs, and - very importantly - its dual-use, I would personally be very tempted to have one.
Unless a significant drawback was found - but pollutants don't appear to be one of them.

Thanks. The post I quoted did strike me as quite alarmist and as someone else pointed out read more like lpg propaganda.

There are probably millions of people using diesel heater for many years now and while that is not testament to their safety necessarily, in my months of reading I havent read such warnings as to beware of them for particular health concerns.

GervisLooper

Apparently the diesel heaters can run fine on cooking oil/biodiesel so this would likely work with it as well since their internal operations are almost identical from what I have read.

Video.

ThisIsWeird

That vid brings to mind a different issue - are these hob/heaters noisy in use? Is there a dealer you can visit to see it in operation?
Going back to the 'pollution' issue, due to its size if nothing else, it is surely insignificant. And I'd imagine, in a decent van conversion, you'll rarely even be using it flat out - perhaps for a half hour to heat the van up from cold. 
Yours will be a small room, nicely draught proof, and hopefully with a decent level of insulation all around - I'd imagine you'd be having it ticking over at comfortably under 1kW for the majority of the time, and a matter of a couple of hundred watts overnight, if at all.
I'd have thought another advantage of the diesel system is that you use fuel already on board in your van's tank - will that not be the case? Even if not, I would do my research before using anything like cooking oil, in case it'll produce extra carbons and products that could coat the burner and chamber. I have no idea if it could, but I would find out to be sure.

ashe

GervisLooper said:

Andy_L said:

Its £28 for 6kg of propane, not £40 (so ~1/2 the price of the 220g bottles) ETA:  which will make a big difference to your break-even calculation

https://www.calor.co.uk/lpg-prices

It may say that on the site but places where you can actually buy it, resellers, where you go and pick it up, from my research the prices are around £40.

A couple more £35 odd yea.

https://www.adamsgas.co.uk/product/calor-gas-propane-6kg-refill/

Is that because of the size? I get the larger 13kg cylinders delivered for £35 by a local firm for my pizza oven and never had to give a deposit 

Andy_L

ashe said:

GervisLooper said:

Andy_L said:

Its £28 for 6kg of propane, not £40 (so ~1/2 the price of the 220g bottles) ETA:  which will make a big difference to your break-even calculation

https://www.calor.co.uk/lpg-prices

It may say that on the site but places where you can actually buy it, resellers, where you go and pick it up, from my research the prices are around £40.

A couple more £35 odd yea.

https://www.adamsgas.co.uk/product/calor-gas-propane-6kg-refill/

Is that because of the size? I get the larger 13kg cylinders delivered for £35 by a local firm for my pizza oven and never had to give a deposit 

It looks like they've had supply issues with the 6kg. They discontinued their other design of 6kg cylinder so everyone has had to switch to that one pushing up demand.

Mind you, £35 for 13kg of propane delivered & no cylinder deposit is an amazingly good price. Don't enquire to closely - they might realise they've been cocking up the bill ;-)