ENERGY ON THE MOVE by John Welham
No, this is not about how to retain your resources as you walk and talk to the next pub. It is about a couple of ways of getting the best out of your motorhome whilst on the move or parked up for longer periods without mains electric. Batteries and gas are what it is all about.
PART 1 BATTERIES
We have all wanted to stay longer at that idyllic beach side wild camp or basic parking ground, but the domestic battery is getting a bit low and needs a recharge. The obvious starting point is to fit more battery capacity (but without exceeding the Maximum Allowable Mass). Many vans have room to fit a second, (or third), battery alongside the original fit, allowing you to multiply the on-board capacity very easily. Remember that it is no good adding a new battery to an old one; the old one will simply drain the new one and will waste your money. If the original battery is more than a year old it is always best to replace the this as well, and both (or all) batteries should be of the same type and capacity. In my case there was no room to fit an additional battery in the compartment, so the next option was to look at a single, bigger battery. All batteries come in standard case sizes, which mean that you can often fit a taller battery with the same footprint as the original. This is a simple drop in and may give you up to 50% additional capacity, for example, 90Ah increase to 135Ah. In my case I wanted to go from an installed 100Ah to more than 200Ah, so I had to relocate the battery stowage. Battery type, ie, open lead acid, sealed lead acid, AGM, or gel, I will return to that later.
After fitting as much battery capacity as you can sensibly get in within the vehicle maximum weight, we all generally next opt for solar panels. Great in the middle of summer, with long daylight hours, high sun angles and fine weather. Not so effective during the winter months, even when in southern Spain or on the Algarve. On fine days there will be some charge from the panels, but probably not enough to compensate, particularly during the long dark and much cooler hours, so eventually the batteries need recharging. To do this you will either have to go for a long run, maybe 200 – 300 miles to get a decent charge, or find a site with a hook up. Even this will not charge the batteries completely. Standard engine driven alternators will only recharge the domestic batteries to about 70% capacity, and many on board mains chargers will do little better, (although some Laika fitted mains chargers can be set to provide a full charge). Your batteries are not even starting from full when you park next to that idyllic view.
The reason for this is that the maximum charging voltage from the alternator is limited to about 14.2 -14.4 volts, whereas lead acid batteries need up to 14.8 volts to achieve a full charge. Basically, vehicle alternator controllers are designed to replace the charge in the vehicle starter battery, and to power the vehicles 12 volt services, eg, ECU, lights, heater fan, etc. They are not designed to completely recharge a very run down domestic battery situated some distance form the engine bay. You will eventually get up to the 70% state of charge, but this requires a long time. Alternators fitted to chassis destined for motorcaravan conversion are often higher rated, so there is plenty of spare power in the alternator to charge batteries fully and quickly (For example, mine is rated at 150 A.) The way to do this is to replaced the alternator controller, either physically, or by fitting additional equipment. Advanced alternator controllers are available. They require some minor modification of the alternator connections, but have the disadvantage that they supply the higher voltages to the whole vehicle electrical system. Some vehicle systems might not like seeing an extra half volt or so, e.g. the engine ECU, and advice on this is contradictory. Another option is to fit a device between the standard alternator controller and the domestic batteries. This provides the optimum charge regime to the domestic batteries, but does not increase the voltage to the standard vehicle electrical systems. This is what I did, and this is how it works.
I fitted a Battery to Battery charger made by Sterling Power Ltd. It is a software controlled DC amplifier that measures the state of the domestic battery every time the vehicle engine is started, and calculates the optimum charging regime to be applied. It is quite straightforward; there are 3 ENERGY ON THE MOVE main connections. The split charge relay is removed, and the unit is connected to the positive terminal of the vehicle battery and the positive terminal of the domestic battery. The negative terminals are connected in common and grounded to chassis earth. These connections have to be made with heavy duty cable to carry the high currents. There are other connections to temperature sensors for the domestic battery and alternator, and a battery voltage sensing lead, but these are ordinary wires. When the engine is started, the unit first allows the alternator to recharge the vehicle battery. This takes about 2 - 3 minutes for the alternator to achieve 13.0 volts at the battery, except in the case of a much discharged battery. The unit then starts the charging process by artificially loading the vehicle battery to hold the voltage down to not less than 13.0 volts so the alternator thinks the vehicle battery still needs a high charge current. The unit then feeds this current to the domestic battery. (My unit is rated at 50 amps, and I have actually seen nearly 40 amps being fed to the domestic battery.) The unit continues to control the charge to the domestic battery by increasing the voltage as the charge current reduces until the magic 14.8 volts is reached. Whilst it is doing this, it periodically checks the vehicle battery, by unloading it to check its charge state, and tops up the charge as necessary. Once the domestic battery achieves 14.8 volts, it is maintained at this level for a calculated period of time to soak the battery at a reducing current until the full charge state is achieved. Once this occurs, the voltage is reduced to a float charge of about 13.6 volts. The battery is fully charged at this point, and will remain so until you have completed your journey. Charging at 14.8 volts has the added benefit of desulphating the battery, thus greatly extending its useful life. However, the batteries do use more water with rapid charging, so they need checking and topping up more frequently.
Sterling Power claim that you will achieve a full charge in about one fifth of the time it would normally take by being able to charge with the very high current and soaking the battery at the optimum charge voltage. These are things that an alternator would not normally do. So what you get as a motorcaravanner is a 100% full battery during a relatively short journey. The actual time required of course depends on how far the battery is discharged.
Which brings us to what type of battery to use. Sterling’s advice is to use the cheapest open lead acid battery around, see www.sterling-power.com/support-faq-2.htm . All batteries are essentially lead acid but some are modified. For sealed batteries of any type, or AGMs or gels, whilst you might be able to use them safely and without spillage inverted or at high angles of lean, (this is generally not recommended for motorcaravans!), you cannot feed them with the high currents nor take them up to 14.8 volts. Above about 14.5 volts the battery produces Hydrogen gas, which has to escape, which is why lead acid batteries are vented to atmosphere. In sealed batteries gassing would increase the pressure inside the battery case and may lead to the case splitting.
In AGMs and gel batteries, not only are they unable to safely take high charge currents eg, they are limited to approx maximum of 10% of their Ah rating, as the electrolyte is not in a free liquid state, the bubbles of Hydrogen would form above 14.5 volts that would not be able to dissipate, thus significantly reducing the flow of charge through the electrolyte, essentially, permanently damaging the battery. Sterling’s Battery to Battery charger can be set to provide a charge regime suitable for these other types of battery, but you cannot achieve the same rapid charge as with open lead acid batteries, although it would be better than a standard alternator.
I fitted 2 new 235Ah 6 volt traction batteries, ( ie, the typed used in golf buggies and fork lifts) and connected them in series to produce a 12 volt supply. I used traction batteries because they are designed to cycle down to 50% discharge or less, but they cannot provide high currents for engine cranking. They cost a little more than the equivalent, good quality 12 volt semi-traction batteries (about £100 each). These latter do have a cranking rating, are often called deep cycle, but will not last as long as true traction types. For things like gel batteries I was quoted £500 for a 220Ah unit. Probably necessary in an ocean going power boat, but totally over the top for a motorcaravan!
The end result is that you will be able to stay still longer; you will recharge the battery as quickly as possible, even by just running the engine without going anywhere if this is possible without annoying the neighbours. We have also fitted an 1800 watt inverter that enables us to use a small mains kettle during stops en route, but there are a myriad of other mains electrical things that now become possible because the domestic battery can by recharged quickly, eg, microwave, small washing machine, food mixer, cookpot, TV & DVD ……
A 50 Amp Battery to Battery charger is now nearly £300, a significant increase since last summer when it was listed at £175. The cabling plus high rated fuses (250 A) and end connectors and other bits cost about £100. The Sterling units are sold by Road Pro, BatteryMegastore and Van Bitz. (BatteryMegastore will negotiate on price and also has a vast stock of batteries.) Van Bitz will do a complete installation but I do not know the current cost. Do not be tempted to skimp on upgrading the cabling. The high currents need bigger cables to be safe and efficient.
Does it work you ask? Ours was fitted before we went to Tunisia. We went down through France and Italy and backagain in Oct/Nov/Dec last year. We had infrequent access to hook ups, and even where they existed, they usually only had enough power to keep the fridge running. We used the mains kettle and cookpot frequently; we spent several days at a time parked up; on the way back through a very wintery Europe, we often had the gas heating running overnight with the fan blowing. Overall, the battery worked hard, but when we stopped we always had a full charge.
I spent the best part of a year researching the best batteries to fit and the best way to keep them charged. Most of the equipment I looked at has origins in the leisure marine arena, but it is equally applicable to motorcaravans. In the end I found the advice provided by Sterling Power to be the most relevant. It is practical and does not attempt to lead you to the most expensive solution. They make good quality equipment and it is relatively simple to fit. Most of the information given above has been learnt from their website, which I strongly urge you to look at if you want to know more www.sterling-power.com . Alternatively, Van Bitz are their usual very helpful self if you want to learn more from them.
I have provided this account of what I have learnt and applied to installing a battery and charging upgrade for information only. It is not intended to be a detailed guide on how to do it. It is intended to indicate one approach to improving motorcaravaning autonomy, and highlight some of the technical aspects that need to be addressed. If you want to know more, then I would be happy to point you at the sources of information. Alternatively, you should contact some of the manufacturers or professional installers for advice.
PART 2 NOW THE GAS
In Part 1 I suggested a way of improving your motorcaravan’s electrical autonomy by fitting a fast charging unit. I will now cover the issue of gas supplies. This is a whole lot less complex. You may have read in the March Newsletter Peter Elliott’s account of Calor gas consumption during a longish trip to southern parts earlier this year. Peter concluded that with enough access to mains hook up to allow electric rather than gas to be the prime source of energy, then a couple of 13Kg Propane cylinders are enough, even in winter, although I think I detected the odd chilly night somewhere in the account. I would generally concur with his conclusion. We once did 6 weeks in Norway in summer, spending 4 weeks above the Arctic Circle without any hook ups, where 2 bottles just about lasted, but we were very careful. However, if you are moving a lot, it is really cold and you want to be warm, and there are no hook ups, then gas consumption goes up significantly. I decided to go down the refillable gas route before we went to Morocco over 2 years ago, so we now have had 2 major tours to North Africa and several longish trips through Europe to gain experience with refillables.
Why choose refillables in the first place? The answer is convenience and cost. With Calor bottles, when embarking on a long trip it was essential to set off with a full supply of gas, because you cannot get replacements whilst away. This usually meant giving back to Calor with up to half a bottle of gas, hence increasing the real cost of the replacement gas significantly. Whilst away, we had to use gas carefully, because although there are places where you can get a Calor bottle refilled, they are known to but a few, and usually at the other end of whatever country you are in. If you use BP Light bottles instead, although they are becoming more available in the UK and Europe, there is still no UK – Europe bottle inter-change despite being around for well over 2 years now. Another alternative is to buy a European bottle and attachment from somewhere like France or Germany so that you can get refills whilst away, but his still gives additional cost and complexity. So if you reckon you are going to need more than 2 bottles worth of gas, then refillables could be an answer.
If I remember correctly it cost about £250 - £300 to fit 2 Gaslow 11 Kg bottles with hoses and adaptors. The real payback is in the convenience of being able to restore full gas stocks wherever you can find an Autogas station, so you do not have to be overly concerned about conserving gas. Autogas is now widely available in the UK and Europe, with the exception of Spain. This is because it is only about 4 years ago that it became legal for private vehicles, as opposed to buses and taxis, to use LPG for motive fuel. Hence it is taking a long time for the LPG infrastructure to be deployed. Given that many new cars are diesel, it seems unlikely to me that LPG deployment will advance rapidly. Having said that, hunting through the Repsol and Cepsa websites it is possible to find the locations of Autogas stations. Autogas is widespread in France and Italy, and we have even found it in Portugal. We were even able to refill with Autogas in Tunisia, where along the eastern Mediterranean coast at least, every other fuel station seemed to have it.
On the cost side of the equation, Autogas is about half the unit cost compared to Calor. That, along with not having to return only part used bottles, means that there is a reasonable payback to offset the original cost. There are alternatives to the Gaslow refillable bottles. Fixed Propane tanks have been around a long time, but they seem expensive to fit.
There are some drawbacks to the Gaslow refillable bottles. They hold only 11 Kg of gas compared to 13 Kg in a nearly similar sized Calor bottle. Given the general ease at being able to refill almost a will, this is not a major drawback. A more significant issue may be, that whilst Autogas supplied in the UK is 100% Propane, European Autogas is a mix of Propane and Butane. Not a problem for your gas appliances, but remember that Butane freezes at around 0 degrees Celsius. So in winter, if the ambient temperature is around freezing, then all the Propane will evaporate first leaving you with a frozen bottle of Butane. The trick is go away with both bottles full of UK Propane and if you are using gas in cold conditions, keep one bottle to refill with mixed gases, for use when the temperature is above freezing, and keep the other bottle of Propane for use when Propane is essential. This means refilling the one bottle more often, but it works. Unless you are off for a couple of weeks in the winter Alps, then with a bit of care, you should always have enough of gas of the right type whatever the outside temperature.
Another minor problem is that if you have a Propane pressure gauge fitted to your system, and you are using mixed Autogas, then the gauge will not give you a correct reading. Butane has a lower partial pressure than Propane, so a Propane calibrated gauge will give an under reading, even when mixed with Propane. If you have a Butane pressure gauge, you should not use it at all with Propane or mixes; the higher Propane pressure will damage the gauge and may lead to a leak. So its back to the hot water method of finding how much gas is in the bottle. You also need at least 2 additional adaptors to enable you to use the Autogas filling hoses throughout Europe. One for France and Italy, and another for elsewhere.
If you are away from fixed, serviced sites for any length of time, then refillable gas bottles are a good way of ensuring that you have enough stored energy to cook, keep the beer and wine cold, keep warm and not wash in cold water. With the exception of Spain, it would be possible to keep an adequate supply of gas indefinitely. Even in Spain it is possible to refill if planned into your itinerary.
Combining adequate domestic battery capacity and rapid recharge with refillable gas bottles are a very effective way of extending the autonomy of your motorcaravan. Mid-size motorcaravans that seem to predominate in the club, have limited space and weight for energy storage. Being able to replenish those energy reservoirs easily, and relatively cheaply, has to be the effective way of extending your independence from serviced sites (another cost saving), and maintaining comfort whatever the weather. A more recent trend is towards diesel fuelled heating and cooking with a compressor fridge, and no gas at all. This is not really an aftermarket option, but will probably gain ground in new models in the future. The fuel cell, using methanol to generate electricity seems a very expensive way of achieving electrical autonomy, and you still have to carry the base fuel, ie, methanol.
A final thought. One of the Germans that we toured Tunisia with had an 80 Kg fixed gas tank, 250 litres of fresh water, 200 litre waste tank, and he even carried two 200Ah spare batteries. He needed 2 spare batteries because he was driving a motorhome based upon an 8 tonne MAN chassis, and the starter batteries packed up whilst we were away. Of course, truck electrics run at 24 Volts so he had to connect the batteries in series. Whilst those are impressive storage capacities, his truck was somewhat larger than the average Laika!
No, this is not about how to retain your resources as you walk and talk to the next pub. It is about a couple of ways of getting the best out of your motorhome whilst on the move or parked up for longer periods without mains electric. Batteries and gas are what it is all about.
PART 1 BATTERIES
We have all wanted to stay longer at that idyllic beach side wild camp or basic parking ground, but the domestic battery is getting a bit low and needs a recharge. The obvious starting point is to fit more battery capacity (but without exceeding the Maximum Allowable Mass). Many vans have room to fit a second, (or third), battery alongside the original fit, allowing you to multiply the on-board capacity very easily. Remember that it is no good adding a new battery to an old one; the old one will simply drain the new one and will waste your money. If the original battery is more than a year old it is always best to replace the this as well, and both (or all) batteries should be of the same type and capacity. In my case there was no room to fit an additional battery in the compartment, so the next option was to look at a single, bigger battery. All batteries come in standard case sizes, which mean that you can often fit a taller battery with the same footprint as the original. This is a simple drop in and may give you up to 50% additional capacity, for example, 90Ah increase to 135Ah. In my case I wanted to go from an installed 100Ah to more than 200Ah, so I had to relocate the battery stowage. Battery type, ie, open lead acid, sealed lead acid, AGM, or gel, I will return to that later.
After fitting as much battery capacity as you can sensibly get in within the vehicle maximum weight, we all generally next opt for solar panels. Great in the middle of summer, with long daylight hours, high sun angles and fine weather. Not so effective during the winter months, even when in southern Spain or on the Algarve. On fine days there will be some charge from the panels, but probably not enough to compensate, particularly during the long dark and much cooler hours, so eventually the batteries need recharging. To do this you will either have to go for a long run, maybe 200 – 300 miles to get a decent charge, or find a site with a hook up. Even this will not charge the batteries completely. Standard engine driven alternators will only recharge the domestic batteries to about 70% capacity, and many on board mains chargers will do little better, (although some Laika fitted mains chargers can be set to provide a full charge). Your batteries are not even starting from full when you park next to that idyllic view.
The reason for this is that the maximum charging voltage from the alternator is limited to about 14.2 -14.4 volts, whereas lead acid batteries need up to 14.8 volts to achieve a full charge. Basically, vehicle alternator controllers are designed to replace the charge in the vehicle starter battery, and to power the vehicles 12 volt services, eg, ECU, lights, heater fan, etc. They are not designed to completely recharge a very run down domestic battery situated some distance form the engine bay. You will eventually get up to the 70% state of charge, but this requires a long time. Alternators fitted to chassis destined for motorcaravan conversion are often higher rated, so there is plenty of spare power in the alternator to charge batteries fully and quickly (For example, mine is rated at 150 A.) The way to do this is to replaced the alternator controller, either physically, or by fitting additional equipment. Advanced alternator controllers are available. They require some minor modification of the alternator connections, but have the disadvantage that they supply the higher voltages to the whole vehicle electrical system. Some vehicle systems might not like seeing an extra half volt or so, e.g. the engine ECU, and advice on this is contradictory. Another option is to fit a device between the standard alternator controller and the domestic batteries. This provides the optimum charge regime to the domestic batteries, but does not increase the voltage to the standard vehicle electrical systems. This is what I did, and this is how it works.
I fitted a Battery to Battery charger made by Sterling Power Ltd. It is a software controlled DC amplifier that measures the state of the domestic battery every time the vehicle engine is started, and calculates the optimum charging regime to be applied. It is quite straightforward; there are 3 ENERGY ON THE MOVE main connections. The split charge relay is removed, and the unit is connected to the positive terminal of the vehicle battery and the positive terminal of the domestic battery. The negative terminals are connected in common and grounded to chassis earth. These connections have to be made with heavy duty cable to carry the high currents. There are other connections to temperature sensors for the domestic battery and alternator, and a battery voltage sensing lead, but these are ordinary wires. When the engine is started, the unit first allows the alternator to recharge the vehicle battery. This takes about 2 - 3 minutes for the alternator to achieve 13.0 volts at the battery, except in the case of a much discharged battery. The unit then starts the charging process by artificially loading the vehicle battery to hold the voltage down to not less than 13.0 volts so the alternator thinks the vehicle battery still needs a high charge current. The unit then feeds this current to the domestic battery. (My unit is rated at 50 amps, and I have actually seen nearly 40 amps being fed to the domestic battery.) The unit continues to control the charge to the domestic battery by increasing the voltage as the charge current reduces until the magic 14.8 volts is reached. Whilst it is doing this, it periodically checks the vehicle battery, by unloading it to check its charge state, and tops up the charge as necessary. Once the domestic battery achieves 14.8 volts, it is maintained at this level for a calculated period of time to soak the battery at a reducing current until the full charge state is achieved. Once this occurs, the voltage is reduced to a float charge of about 13.6 volts. The battery is fully charged at this point, and will remain so until you have completed your journey. Charging at 14.8 volts has the added benefit of desulphating the battery, thus greatly extending its useful life. However, the batteries do use more water with rapid charging, so they need checking and topping up more frequently.
Sterling Power claim that you will achieve a full charge in about one fifth of the time it would normally take by being able to charge with the very high current and soaking the battery at the optimum charge voltage. These are things that an alternator would not normally do. So what you get as a motorcaravanner is a 100% full battery during a relatively short journey. The actual time required of course depends on how far the battery is discharged.
Which brings us to what type of battery to use. Sterling’s advice is to use the cheapest open lead acid battery around, see www.sterling-power.com/support-faq-2.htm . All batteries are essentially lead acid but some are modified. For sealed batteries of any type, or AGMs or gels, whilst you might be able to use them safely and without spillage inverted or at high angles of lean, (this is generally not recommended for motorcaravans!), you cannot feed them with the high currents nor take them up to 14.8 volts. Above about 14.5 volts the battery produces Hydrogen gas, which has to escape, which is why lead acid batteries are vented to atmosphere. In sealed batteries gassing would increase the pressure inside the battery case and may lead to the case splitting.
In AGMs and gel batteries, not only are they unable to safely take high charge currents eg, they are limited to approx maximum of 10% of their Ah rating, as the electrolyte is not in a free liquid state, the bubbles of Hydrogen would form above 14.5 volts that would not be able to dissipate, thus significantly reducing the flow of charge through the electrolyte, essentially, permanently damaging the battery. Sterling’s Battery to Battery charger can be set to provide a charge regime suitable for these other types of battery, but you cannot achieve the same rapid charge as with open lead acid batteries, although it would be better than a standard alternator.
I fitted 2 new 235Ah 6 volt traction batteries, ( ie, the typed used in golf buggies and fork lifts) and connected them in series to produce a 12 volt supply. I used traction batteries because they are designed to cycle down to 50% discharge or less, but they cannot provide high currents for engine cranking. They cost a little more than the equivalent, good quality 12 volt semi-traction batteries (about £100 each). These latter do have a cranking rating, are often called deep cycle, but will not last as long as true traction types. For things like gel batteries I was quoted £500 for a 220Ah unit. Probably necessary in an ocean going power boat, but totally over the top for a motorcaravan!
The end result is that you will be able to stay still longer; you will recharge the battery as quickly as possible, even by just running the engine without going anywhere if this is possible without annoying the neighbours. We have also fitted an 1800 watt inverter that enables us to use a small mains kettle during stops en route, but there are a myriad of other mains electrical things that now become possible because the domestic battery can by recharged quickly, eg, microwave, small washing machine, food mixer, cookpot, TV & DVD ……
A 50 Amp Battery to Battery charger is now nearly £300, a significant increase since last summer when it was listed at £175. The cabling plus high rated fuses (250 A) and end connectors and other bits cost about £100. The Sterling units are sold by Road Pro, BatteryMegastore and Van Bitz. (BatteryMegastore will negotiate on price and also has a vast stock of batteries.) Van Bitz will do a complete installation but I do not know the current cost. Do not be tempted to skimp on upgrading the cabling. The high currents need bigger cables to be safe and efficient.
Does it work you ask? Ours was fitted before we went to Tunisia. We went down through France and Italy and backagain in Oct/Nov/Dec last year. We had infrequent access to hook ups, and even where they existed, they usually only had enough power to keep the fridge running. We used the mains kettle and cookpot frequently; we spent several days at a time parked up; on the way back through a very wintery Europe, we often had the gas heating running overnight with the fan blowing. Overall, the battery worked hard, but when we stopped we always had a full charge.
I spent the best part of a year researching the best batteries to fit and the best way to keep them charged. Most of the equipment I looked at has origins in the leisure marine arena, but it is equally applicable to motorcaravans. In the end I found the advice provided by Sterling Power to be the most relevant. It is practical and does not attempt to lead you to the most expensive solution. They make good quality equipment and it is relatively simple to fit. Most of the information given above has been learnt from their website, which I strongly urge you to look at if you want to know more www.sterling-power.com . Alternatively, Van Bitz are their usual very helpful self if you want to learn more from them.
I have provided this account of what I have learnt and applied to installing a battery and charging upgrade for information only. It is not intended to be a detailed guide on how to do it. It is intended to indicate one approach to improving motorcaravaning autonomy, and highlight some of the technical aspects that need to be addressed. If you want to know more, then I would be happy to point you at the sources of information. Alternatively, you should contact some of the manufacturers or professional installers for advice.
PART 2 NOW THE GAS
In Part 1 I suggested a way of improving your motorcaravan’s electrical autonomy by fitting a fast charging unit. I will now cover the issue of gas supplies. This is a whole lot less complex. You may have read in the March Newsletter Peter Elliott’s account of Calor gas consumption during a longish trip to southern parts earlier this year. Peter concluded that with enough access to mains hook up to allow electric rather than gas to be the prime source of energy, then a couple of 13Kg Propane cylinders are enough, even in winter, although I think I detected the odd chilly night somewhere in the account. I would generally concur with his conclusion. We once did 6 weeks in Norway in summer, spending 4 weeks above the Arctic Circle without any hook ups, where 2 bottles just about lasted, but we were very careful. However, if you are moving a lot, it is really cold and you want to be warm, and there are no hook ups, then gas consumption goes up significantly. I decided to go down the refillable gas route before we went to Morocco over 2 years ago, so we now have had 2 major tours to North Africa and several longish trips through Europe to gain experience with refillables.
Why choose refillables in the first place? The answer is convenience and cost. With Calor bottles, when embarking on a long trip it was essential to set off with a full supply of gas, because you cannot get replacements whilst away. This usually meant giving back to Calor with up to half a bottle of gas, hence increasing the real cost of the replacement gas significantly. Whilst away, we had to use gas carefully, because although there are places where you can get a Calor bottle refilled, they are known to but a few, and usually at the other end of whatever country you are in. If you use BP Light bottles instead, although they are becoming more available in the UK and Europe, there is still no UK – Europe bottle inter-change despite being around for well over 2 years now. Another alternative is to buy a European bottle and attachment from somewhere like France or Germany so that you can get refills whilst away, but his still gives additional cost and complexity. So if you reckon you are going to need more than 2 bottles worth of gas, then refillables could be an answer.
If I remember correctly it cost about £250 - £300 to fit 2 Gaslow 11 Kg bottles with hoses and adaptors. The real payback is in the convenience of being able to restore full gas stocks wherever you can find an Autogas station, so you do not have to be overly concerned about conserving gas. Autogas is now widely available in the UK and Europe, with the exception of Spain. This is because it is only about 4 years ago that it became legal for private vehicles, as opposed to buses and taxis, to use LPG for motive fuel. Hence it is taking a long time for the LPG infrastructure to be deployed. Given that many new cars are diesel, it seems unlikely to me that LPG deployment will advance rapidly. Having said that, hunting through the Repsol and Cepsa websites it is possible to find the locations of Autogas stations. Autogas is widespread in France and Italy, and we have even found it in Portugal. We were even able to refill with Autogas in Tunisia, where along the eastern Mediterranean coast at least, every other fuel station seemed to have it.
On the cost side of the equation, Autogas is about half the unit cost compared to Calor. That, along with not having to return only part used bottles, means that there is a reasonable payback to offset the original cost. There are alternatives to the Gaslow refillable bottles. Fixed Propane tanks have been around a long time, but they seem expensive to fit.
There are some drawbacks to the Gaslow refillable bottles. They hold only 11 Kg of gas compared to 13 Kg in a nearly similar sized Calor bottle. Given the general ease at being able to refill almost a will, this is not a major drawback. A more significant issue may be, that whilst Autogas supplied in the UK is 100% Propane, European Autogas is a mix of Propane and Butane. Not a problem for your gas appliances, but remember that Butane freezes at around 0 degrees Celsius. So in winter, if the ambient temperature is around freezing, then all the Propane will evaporate first leaving you with a frozen bottle of Butane. The trick is go away with both bottles full of UK Propane and if you are using gas in cold conditions, keep one bottle to refill with mixed gases, for use when the temperature is above freezing, and keep the other bottle of Propane for use when Propane is essential. This means refilling the one bottle more often, but it works. Unless you are off for a couple of weeks in the winter Alps, then with a bit of care, you should always have enough of gas of the right type whatever the outside temperature.
Another minor problem is that if you have a Propane pressure gauge fitted to your system, and you are using mixed Autogas, then the gauge will not give you a correct reading. Butane has a lower partial pressure than Propane, so a Propane calibrated gauge will give an under reading, even when mixed with Propane. If you have a Butane pressure gauge, you should not use it at all with Propane or mixes; the higher Propane pressure will damage the gauge and may lead to a leak. So its back to the hot water method of finding how much gas is in the bottle. You also need at least 2 additional adaptors to enable you to use the Autogas filling hoses throughout Europe. One for France and Italy, and another for elsewhere.
If you are away from fixed, serviced sites for any length of time, then refillable gas bottles are a good way of ensuring that you have enough stored energy to cook, keep the beer and wine cold, keep warm and not wash in cold water. With the exception of Spain, it would be possible to keep an adequate supply of gas indefinitely. Even in Spain it is possible to refill if planned into your itinerary.
Combining adequate domestic battery capacity and rapid recharge with refillable gas bottles are a very effective way of extending the autonomy of your motorcaravan. Mid-size motorcaravans that seem to predominate in the club, have limited space and weight for energy storage. Being able to replenish those energy reservoirs easily, and relatively cheaply, has to be the effective way of extending your independence from serviced sites (another cost saving), and maintaining comfort whatever the weather. A more recent trend is towards diesel fuelled heating and cooking with a compressor fridge, and no gas at all. This is not really an aftermarket option, but will probably gain ground in new models in the future. The fuel cell, using methanol to generate electricity seems a very expensive way of achieving electrical autonomy, and you still have to carry the base fuel, ie, methanol.
A final thought. One of the Germans that we toured Tunisia with had an 80 Kg fixed gas tank, 250 litres of fresh water, 200 litre waste tank, and he even carried two 200Ah spare batteries. He needed 2 spare batteries because he was driving a motorhome based upon an 8 tonne MAN chassis, and the starter batteries packed up whilst we were away. Of course, truck electrics run at 24 Volts so he had to connect the batteries in series. Whilst those are impressive storage capacities, his truck was somewhat larger than the average Laika!
