12 volt sleeping bag, swag & tent heating

[tektrek]

G'day,

I'm looking at manufacturing or importing high efficiency 12 volt electric blankets/mats for insertion into sleeping bags and swags following complaints over many years from various partners about camping in cooler weather. Conventional electric blankets running through DC-AC inverters are inefficient and flatten a 60Ah deep cycle battery well before day break.

How do you feel about this? If such an item was available would it encourage your other half to join you on trips in winter? Power consumption of a sleeping bag insert for example @ 38-40deg would be in the range of 2-3 amps/hour at 12 volts running via an adjustable thermostat (body core temp is 38deg, any warmer and you'll sweat). A slightly larger version could be made available for camper trailer beds. Current 12 volt electric blankets from a US manufacturer that actually work (!) draw around 8-10 amps an hour.

I'm looking at not just sleeping bag inserts either. I've been thinking about a heated mat to go in tents and camper trailers as a form of central heating bringing the internal ambient air temp up to a liveable 21-25degC using the latest in heating technology - no more frozen clothes in the morning nor warm feet hitting a frozen tent floor. I can go higher in temp if need be, in fact up to 180degC or more like with Formula One tyre wrmers! And yes I know about thermal loss thru the tent fabric but this can also be overcome to some degree with a thermally insulated wrap around tent fly.

I'm also looking at an aftermarket kit to keep diesel fuel lines, tanks, pumps and filters in diesel 4WDs & trucks at 15-20degC for use in sub zero conditions like the VIC/NSW high country in winter. Power could be derived from a small 7.2v NiMH or Li-ION rechargeable battery pack or alternatively from a 12v dual battery setup @ approx 1A/hr or less.

Would I have a market here considering alpine diesel is going to be around $1-80 to $2-00+ a litre this winter in the snow towns?

Please let me know how you feel about the above ideas and if they are a goer in Oz or should I just stick to the US and European markets.

 

[Swaggie]

Not sure about the swag bit,because swags retain a shitload of heat and normaly you strip gear off....Tents with open spaces could be a goer though....Sounds a good idea but would need further testing...Now because we hav had a wet summer i'm suprised while just touring in victorias hardest areas that there hasnt been much traffic about.....So that says to me that people stay away if it likely to be wet or cold or both....(hence i'm not sure a 12 volt heating would make much diff)....



Goodluck

 

[NIAL8R]

Never seen a 3 phase dildo yet.......Maybe another market....

i didnt know you batted for both teams Wayne

there could be a market for those with tents and campers although in the colder months i have always just taken a couple of hot water bottles with me. heat the water in the billy and wall'a im making love to them all night long and the water i just re-use the next night and so on. just remember to take 2 billy's, one for the bottles and one for coffee/tea other wise you get a lovley rubber taste trough ya cuppa, yes i learnt the hard way

 

[BUSHNUT]

Interesting ! It would depend very much on the battery drain .

What sort of bucks are we talking ?

 

[Big Matt]

Not 100% sure but cant you cant you get these for caravans already ?

 

[tektrek]

i didnt know you batted for both teams Wayne

there could be a market for those with tents and campers although in the colder months i have always just taken a couple of hot water bottles with me. heat the water in the billy and wall'a im making love to them all night long and the water i just re-use the next night and so on. just remember to take 2 billy's, one for the bottles and one for coffee/tea other wise you get a lovley rubber taste trough ya cuppa, yes i learnt the hard way

I've been using hot water bottles for years but I'm tired of finding them luke warm to cold when I wake up hence my ideas.

I hate rubber tasting coffee or tea too.

 

[tektrek]

Interesting ! It would depend very much on the battery drain .

What sort of bucks are we talking ?

Hopefully my ideas will retail around the $120 mark with smaller versions around $50 or so.

Battery drain would be around 2 amps max continuous but can get down below 1 amp with a cycling circuit. In conjunction with another manufacturer I am looking at a 7.2v NiMH battery pack that will heat just around the upper body region for 6+ hours. An alternative is to use a 2 piece car seat warmer that draws 2 amps cont. @ 12 volts. This can be powered from a 12v 24Ahr solar battery pack that I currently make for camp lighting and radio communications. Considering most people sleep for 8hrs average the power draw would be at most 16 amps which any second battery can supply. With smaller compact 4WDs and AWDs I am also trying to bring down the cost of an under driver seat 40-80A/hr lithium aux battery setup, this can also power any warmer/heater.

 

[tektrek]

Not 100% sure but cant you cant you get these for caravans already ?

You are quite correct but those ones draw upwards of 10 amps which means that they will flatten most second batteries easily overnight. When that happens you would need to go for a drive of at least 3 hours to recharge the supply battery.

My warmers operate at a drastically lower current draw meaning that the recharging of a aux battery need to be done every 4th or 5th day unless you were using one the smaller 7.5 alkaline /7.2v Ni-MH heaters.

On the other hand you could go to bed wearing a heated jacket and pants which we are also looking at, these being for watching the footy or fishing in mid winter for example.

 

[NIAL8R]

sounds like you have it all worked out thats for sure, so really it would use less power or there abouts than leaving your interior light on for say 6hrs ??

 

[Jarh73]

Ummmmmm just a though but is 14 watts of heat really worth bothering with?

To make anything worthwhile you need to look at the watts any heating device is rated at. The watts determines the heat output and the watts determines your current draw regardless if voltage.

Based on what you have said the heat output would be stuff all anyway. Nothing an extra blanket couldn't fix.

You need to sit down and do some calculations. It's all very simple stuff but it will show you that producing decent heat that you could use requires significant energy no matter how you do it.

Cheers

Justin

 

[BUSHNUT]

Bugger the top half, its the feet and lowerback where I cop it .

We will gladly test them for you !!!!

 

[tektrek]

Bugger the top half, its the feet and lowerback where I cop it .

We will gladly test them for you !!!!

I'm personally looking at a 3 section mat thingy that will heat around the shoulders, kidney and feet area with minimal power draw.

If it works out I'll let you know Bushnut.

 

[goldrush]

Keep me informed Tektrek. All us Qld'ers are scared of the cold.

 

[Agent 13]

I'm personally looking at a 3 section mat thingy that will heat around the shoulders, kidney and feet area with minimal power draw.

If it works out I'll let you know Bushnut.

This is a completely foriegn concept for me. At 40, I've been camping since I was a kid. If you have a quality bag, down filled and rated for comfort at say minus 5 (which is DIFFERENT to a minus five rating...), surely the most you could need would be something around the feet?? If you're cold, the bag aint good enough. Only time I've been cold was when I made the mistake of buying a non-superdown bag. I dont care what they say, if it's not superdown it's not worth having, especially if your this concerned about the cold.

Usually I have to unzip the bag and use it like a doona!!

 

[Big Matt]

Usually I have to unzip the bag and use it like a doona!!

I always unzip mine and in my swag i never been cold

In an old swag i used to use when i was living up near lake eildon, we used to camp out right through winter and even woke up a few mornings under 6 inches of snow and was never cold

Its all about quality bedding

 

[oznog05]

I like the idea of heating the camper trailer or tent.

Would you be able to incorporate a timer so it could turn on and off automatically? To save power set it to come on in the morning when you need it.

 

[Big Rig]

G'day,

I'm looking at manufacturing or importing high efficiency 12 volt electric blankets/mats for insertion into sleeping bags and swags following complaints over many years from various partners about camping in cooler weather. Conventional electric blankets running through DC-AC inverters are inefficient and flatten a 60Ah deep cycle battery well before day break.

How do you feel about this? If such an item was available would it encourage your other half to join you on trips in winter? Power consumption of a sleeping bag insert for example @ 38-40deg would be in the range of 2-3 amps/hour at 12 volts running via an adjustable thermostat (body core temp is 38deg, any warmer and you'll sweat). A slightly larger version could be made available for camper trailer beds. Current 12 volt electric blankets from a US manufacturer that actually work (!) draw around 8-10 amps an hour.

I'm looking at not just sleeping bag inserts either. I've been thinking about a heated mat to go in tents and camper trailers as a form of central heating bringing the internal ambient air temp up to a liveable 21-25degC using the latest in heating technology - no more frozen clothes in the morning nor warm feet hitting a frozen tent floor. I can go higher in temp if need be, in fact up to 180degC or more like with Formula One tyre wrmers! And yes I know about thermal loss thru the tent fabric but this can also be overcome to some degree with a thermally insulated wrap around tent fly.

I'm also looking at an aftermarket kit to keep diesel fuel lines, tanks, pumps and filters in diesel 4WDs & trucks at 15-20degC for use in sub zero conditions like the VIC/NSW high country in winter. Power could be derived from a small 7.2v NiMH or Li-ION rechargeable battery pack or alternatively from a 12v dual battery setup @ approx 1A/hr or less.

Would I have a market here considering alpine diesel is going to be around $1-80 to $2-00+ a litre this winter in the snow towns?

Please let me know how you feel about the above ideas and if they are a goer in Oz or should I just stick to the US and European markets.

There is such a thing available. Its called a gel membrane heater. Its an option with the Kimberley Kampers. I got one in mine and they do work a treat.

 

[Vegetoast]

We've been using a 12v electric blanket in the winter months for some years now. got it for about $50 off ebay. Turn it on half hour before bed and turn it off when getting in bed, toasty!! never caused us any power problem.

 

[Swaggie]

i didnt know you batted for both teams Wayne

there could be a market for those with tents and campers although in the colder months i have always just taken a couple of hot water bottles with me. heat the water in the billy and wall'a im making love to them all night long and the water i just re-use the next night and so on. just remember to take 2 billy's, one for the bottles and one for coffee/tea other wise you get a lovley rubber taste trough ya cuppa, yes i learnt the hard way

I'd try anything once mate but thats definitely out....lol......

 

[richardlnsw]

heat the water in the billy and wall'a im making love to them all night long


I gather that you must like the smell of burning rubber or do you use gel