Managing your electrics

A wet and dreary weekend, let’s stay in and watch television/play CDs. It’s cold, let’s use the blown air heating, evening comes and the lights grow dim. We have used up most of our available battery power, oops! With the increased amount of electrical gadgetry we fit and expect in our motor homes it is important we understand the consumption rate of our items.

More and more at rallies and on quiet sites we hear the rattle and hum of generators or people returning to their units needing to run their engines when they discover that their leisure or living space battery has insufficient power left to run the required facilities. How many times has this happened to you or someone you know?

First let us consider the source of our electrical power in the living accommodation of our motor home. If you spend most of your time on pitches with mains electric ‘hook-up’ then the following article may be of little interest but for those who don’t and regularly find themselves without battery power for their living needs then maybe the article below will help them manage their power more efficiently. Most motorhomes have a secondary battery fitted to provide these services. In earlier years this was often just another vehicle battery either charged from the vehicle engine whilst travelling or independently charged before departure. In modem units the leisure battery is a specialised battery that can be totally discharged and then recharges again without detriment. These are fitted through charging units, which allow for either charging from the mains when on hook-up or trickle charging from the vehicle alternator when on the move. These batteries are measured in ampere/hours and generally are 75-110 aH. Developments in the field of battery construction mean that with the carbon batteries you can get a larger output battery that is lighter in weight. One living space battery should suffice for year-round weekend use, providing you are careful about how much use is made. Ever more facilities in a Motor Caravan rely on 12v. We now rely on: • Electric pumps for water and toilet flush. The average pump uses 3-5amps, whilst it is not used continuously the total usage for drawing water, showering, etc. can soon add up. lf you have even a small leak in the water system the pump can “cycle” using power. • Fan assisted heating, although heating systems run on gas or diesel the ignition and any circulation fan(s) run from the 12v system. Approximate current consumption for this is 1.4amp. • Electronic ignition for gas appliances (not a great user of power, but inconvenient if you can’t light the fire). • Extraction fans for kitchens and toilets, again the current consumption for these is similar to that for the heating fan. • Even a simple thing as the lighting can run away with power as although the average 8 watt tube light uses no more that 2/3amp, prolonged periods of multi use can soon add up. • Filament lights take a little more current so can run away with the power quickly. Care needs to be taken that lights in cupboards and lockers are not accidentally left on. These should ideally be fitted with a micro switch so the door controls the light being on. It is a good idea to replace filament bulbs with LED type. They use far less current and are available as straight replacements, in most cases tubes can also be replaced the same way. • Heavy current users e.g. colour TV, which can use over 3 amps reduce time available. Add to this CD players, video games or use of computers for the younger motor caravanners, satellite systems and the current is soon used up. A note to remember if you are using an invertor to power mains equipment then there is more current consumption by the invertors, especially if it includes a fan, and that the invertor will consume some power if left on even if no current is being drawn.

To decide which are your great power users – if current consumption is not quoted on the equipment then a quick calculation using Ohms law where power (watts) divided by voltage gives the current will enable you to see where the heavy users are. If you venture away from the beaten track or do not want to rely on hook-ups then you may want more capacity.

It is correct that leisure batteries are designed to have steady drain and then recharge. Starter batteries are made for a quick burst of power to start an engine and then the alternator will recharge the battery. They are not made for long steady drain of power. Traction batteries tend to be rather large and expensive. these are designed

to produce plenty of power BUT they then require overnight charging to replace power. Yes you can use a starter battery but it wont last long being used as a leisure battery in continual use.

Battery Capacity

When choosing a battery you will find they are measured in ampere hour (Ah) this unit is the quantity of current the battery can supply, at the 20 hour rate at 25ºC. A lOOAh battery will supply 5 amps for 20 hours but if the current rises, the supply time falls geometrically. For example, a lOOAh battery supplying 20A may only last for 4 hours, whilst when supplying 3A the same battery could last 40 hours or longer.

To increase your existing supply the first option is to increase your battery capacity, but weight must be considered. There are available on the market carbon batteries, which are lighter but more expensive. Another option for increasing the capacity of your leisure battery is to fit a second battery. Preferably, try to match the leisure battery (60A battery fitted, look for a second 60A battery.) Both batteries must be safely fixed and wired in parallel, i.e. positive to positive, negative to negative. If you have any doubts about how to do this please consult a qualified person. - A medium gauge of wire is needed – 2mm 2 cable. - The link between the two batteries passes half of any current. - Fuse the link at a suitable rate (1OA is often enough). - The fuse must be of a lower rating than the rating of the link wire. - Thinner gauge cable may suffice but will not pass current as efficiently as the heavier gauge cable (copper loss) - No room for a second battery? - Can you fit a larger capacity one? (not necessarily any larger physically) - A third (or even more) living space battery/ies may be fitted – but please watch your payload.

Keeping it all charged

If you move on every day or two or regularly drive your vehicle for 20 or 30 miles per day you can probably ignore this section. Auxiliary battery charging options: Once you have enough battery capacity thoughts often turn to charging the leisure batteries when not running the vehicle. The most obvious is probably a small petrol generator. You already have a generator on board. Running your engine will recharge batteries far quicker than a small portable one. Any mechanical generator will produce some degree of disturbance. A modem generator, which can hardly be heard running at a show or sales yard, may sound very loud indeed when you want to have a nap in the afternoon; on a quiet site it will sound even louder to your neighbours!

Diesel generator sets are usually too heavy and noisy. A further supply of fuel is needed. If the motor caravan runs on diesel and you carry LPG do you also want to carry petrol? You must also remember that periodic maintenance is required to ensure the safety of these items. You may wonder why there are always plenty of petrol generators for sale second hand.

Alternative sources of power are: LPG, wind, and solar generators, and the new kid in the block the Fuel Cell. These are quite expensive and also, as with generators, require a separate fuel to be carried and currently this is only available from certain sources. LPG: A generator fitted on board for the larger motorcaravan can be supplied from the LPG system. This has the advantage in that it saves the need to carry petrol. You will almost certainly carry LPG in any case. The running costs are lower than petrol. LPG is environmentally friendlier, however the points about noise and maintenance referred to with petrol generators still apply. Wind Power: Provides charging power for the longest period providing there is wind but there is the need to raise or erect on site and lower for travelling. The fact that there is mechanical movement means some degree of noise or vibration and inevitably some maintenance. Most wind generators suitable for portable use will provide 0.5 - 1A at best A steady breeze should give 15 - 20A of charge current per day from a 11W unit. Solar Panels: Provides some charging current during daylight hours. If roof fixed then there is practically no maintenance, except cleaning when you wash the motorcaravan roof. You can charge

both battery sets throughout any period of vehicle lay-up. You never get the maximum current out of a panel. A 75W (watt) panel should charge an empty battery at 6A yet is unlikely to better 3A. A normal spring/summer/autumn day will provide around 25 - 30A per day. This gets better with more sun or longer daylight hours. A regulator should be fitted if you plan to leave a panel over 15W permanently connected to one battery. This will prevent overcharging the batteries. Small portable panels of 10 - 25W will not provide sufficient power for real freedom of worry. A minimum of a 50W panel should provide freedom from mains needs for two to three seasons of the year unless you need more 12V power than average. One 75W panel and two 90A hour living space batteries provide freedom from mains for most of the year for many users.

In conclusion, the logical thing is to balance your consumption of electricity. Ensure your leisure battery is fully charged when you arrive on site, careful use of battery power can mean that the fitted leisure battery is sufficient for your purposes. Remember consideration should be given to other site users when running generators or vehicle engines.

Use this chart as a guide to your battery’s condition

State of Sealed or Gel AGM Charge Flooded battery battery Lead Acid

100% 12.70+ 12.85+ 12.80+

75% 12.40 12.65 12.60

50% 12.20 12.35 12.30

25% 12.00 12.00 12.00

0% 11.80 11.80 11.80

Using D.C. Electricity

To understand how D.C. (direct current) electricity works, think of water passing from a tank, through a tap, along a pipe and onto a waterwheel. The water in the tank provides the pressure and this can be compared to ‘voltage’ being measured, of course, in ‘volts’. The flow of water is controlled by the tap and this represents the resistance which the electricity will experience as it travels along a wire. The amount of water passing along the pipe becomes the current which is measured in amperes or ‘amps’. Finally, the water hits the waterwheel and makes it turn. The rate and pressure at which the water turns the wheel is the power and is measured in ‘watts’.

To calculate the number of Amps required for a piece of equipment to operate correctly, use this formula: Amps = Watts/Volts. A 12V TV may use 48 watts of power. When the TV is operated from the mains, the Amps being used will be 48 watts 1230 volts = 0.2 Amps. Hardly anything really but, if you were powering the same TV from the 12V battery in a vehicle, the sum would look like this: 48 watts 112 volts = 4 Amps.

When an appliance is plugged into a 12V/24V socket it will attempt to draw the amount of power which it needs to run correctly. A phone charger may require 0.25 Amps whereas a kettle may need 15 Amps which may be more current than the vehicle’s wiring and sockets are designed to carry. In such a case several things may happen: a fuse could blow, wiring could overheat and melt or the socket could overheat and damage itself or the kettle’s plug. It’s essential therefore to ensure that the wiring, fuses and sockets between an appliance and the battery to which it’s connected, are all ‘fit for purpose’. This should always be borne in mind whenever an appliance is plugged in and appears not to work.

D.C. electricity has a major drawback; when it travels along wires it quickly loses strength. This is known as voltage drop. The longer, thinner and hotter the wire, the greater the resistance and the fewer the volts that make it to the appliance being powered. So, although a voltage can start off at well over 12V when it leaves the battery, by the time it arrives at the appliance, passing through yards of cable and a socket it may only measure 11V or even less. With lights this isn’t a problem, they’ll just dim, but some appliances, TVs for example, may simply not work at all. The solution is to ensure that the wiring between battery and socket is as short as possible and heavy enough to carry the current easily and freely.

It’s absolutely essential to ensure that wiring and sockets are up to the job. If they’re not, not

only may the appliances being powered not work correctly, but damage could be caused and, at worst a fire could start. If in doubt consult an auto electrical specialist

12V/24V 230V Inverters

When you want to use a 230V appliance and you only have 12V or 24V available, you need an inverter. When connected to a 12V or 24V D.C. power source, such as a battery, the inverter simply converts the power into 230V A.C., which can then be used to operate any domestic or light industrial equipment. There are two main kinds of inverter and they have significant differences.

Modified sine wave inverters are the least expensive type. They are usually very efficient, light and compact and range from models supplying less than 150 watts to others, which can power equipment requiring several kilowatts. They work by imitating the waveform produced by 230V mains electricity but the waveform they produce is far from smooth. The result is that some appliances won’t run as smoothly, as efficiently or as quietly as they would normally. TVs usually show interference in the form of a thin line rolling up the screen. Microwave ovens may take a lot longer to cook; battery chargers may overheat or make a buzzing sound; power tools may run roughly and some equipment may be damaged or just won’t work at all. For most applications however, a modified sine wave unit will do the job and the possible disadvantages are outweighed by the low cost of a modified sine wave unit

Pure or True sine wave inverters produce A.C. electricity in a smooth sine wave, which is virtually the same as that supplied by the National Grid. As a result any electrical appliance will run just as well on this type of inverter as it will when plugged into the mains. Their only disadvantage is that they are considerably more expensive but if the inverter is to be used frequently or if maximum performance is essential, they are worth the additional cost

Whichever inverter you choose, it’s essential to get one that is capable of providing the power which the appliance requires. So, if a vacuum cleaner using 1200 watts is being used, the inverter must be capable of supplying 1200 watts. Bear in mind too that a powerful 230V appliance will consume a lot of battery power. ln a vehicle with a 12V battery, use the following formula to calculate exactly how much power the vacuum cleaner will use: Watts (1200) Volts (12) = Amps (100). If the battery supplying the inverter is rated at lOOAh, you might think that the vacuum cleaner would operate for one hour. In practice, however, the battery will run the appliance for perhaps 15 minutes before the voltage drops to a point where the inverter will no longer function. If the battery is holding less than its maximum state of charge or is in poor condition, expect even less running time.

As a rule of thumb, your battery’s AH capacity should be at least 25% of the inverter’s rated output so, if you want to run a 1200W vacuum cleaner, use a 1500W inverter supplied by batteries rated at least 375Ah. (25%of 1500=375)

Many appliances draw a lot more power when starting up than they do when running. A TV, a fridge or anything using an induction motor can draw more than twice the power it needs when actually running. Make sure that your chosen inverter can deal with this surge or peak power. A TV for example, which may use 35 watts when it’s running, could draw as much as 300 watts just for a fraction of a second when it’s switched on.

Having chosen an inverter with the correct power rating. it is essential to fit it correctly. Some models with outputs of up to 300 watts can be connected directly to a lighter socket but make sure that the wiring to the socket and the socket itself are capable of carrying the power required. As a rule, this should not exceed 150 watts. Even in this situation, there could be problems running appliances as a result of voltage drop, especially if the appliance requires a high initial current.

Above 300 watts, an inverter should always be connected directly to a battery and as close to the battery as possible again in order to avoid possible voltage drop. However, because the inverter will consume current even when it’s not being used, ideally it should be capable of being easily switched on and off. This may not be easy if the inverter is hidden away in the battery compartment but, if left on, the inverter will eventually run the battery flat. Some inverters,

usually high output models, have the option of a remote control. This can be easily located somewhere more convenient and solves the problem at a stroke.

Note however, that in vehicles with a 12V or 24V power system, it is always better to use equipment which has been designed to run on those voltages if possible. This is because inverters themselves consume power, even when switched on but not actually powering anything. Most inverters are around 80%- 90% efficient depending on how they are being used. This means that 10 - 20% more power is used to operate an appliance from an inverter than if the same appliance was powered directly from the battery.

Inverters can be extremely useful but they are highly complex pieces of equipment and, as with all electrical products, great care should be taken when installing and using them. Never forget that, even though they only have fairly harmless 12V or 24V going in, the 230V coming out is just as lethal as 230V coming out of a mains socket at home. lnverters can be the source of misunderstandings and problems. It’s tempting and easy to imagine that fitting an inverter to a van, boat or motorhome will solve all the domestic appliance problems. As explained above, it’s not quite that simple.

There are dozens of brands of inverter and hundreds of suppliers. Some brands make claims for themselves, which are, at best bordering on the truth. Others are excellent pieces of equipment but may be just too good for the needs of someone using an inverter occasionally for leisure purposes. However, if you make sure that the inverter you buy is genuinely suitable for your requirements, even if you pay a little more than you’d intended, and if it is fitted correctly and used sensibly, you’ll wonder how you ever lived without it.

Solar Power

There are three kinds of solar panel generally available: amorphous, mono-crystalline and poly-crystalline. All are made from silicon but all have different performance characteristics with amorphous panels being only roughly 1/2 as efficient as mono-crystalline panels. Amorphous panels also have a much shorter lifespan than crystalline models – approx. 10 years as opposed to 25 years+. Amorphous cells are generally found on small, low power panels of the type, which fold up into a case or are designed to sit on a dashboard and plug into the lighter socket. When it comes to producing serious amounts of power, mono-crystalline is the way to go.

In order to produce electricity, any solar panel needs to be exposed to sunlight. On overcast days less power will be produced. Other factors affecting power production are: 1) The angle of the sun in the sky: A solar panel will work most efficiently when it’s perpendicular to the sun, i.e. the sun is striking the panel at an angle of 90 degrees. Because the sun moves, this is a big problem, but there are systems, which automatically track the sun throughout the day. A correctly positioned panel can generate far more power than a badly positioned one. 2) The temperature: Unfortunately, the hotter a solar panel gets the less efficient it becomes at producing electricity. All our panels are mounted in a frame, which allows air to circulate freely and keep the panel cool. 3) Shadows: Because of the way solar panels are constructed, a shadow failing on one cell can drastically reduce the power being supplied by the other cells. For this reason, two panels positioned a few feet apart but wired together can work better than a single large panel.

Choosing a solar panel

Solar panels are rated in terms of their output power: so a 75 watt panel can, in theory and in ideal conditions, produce 75W of power. However, because of the factors mentioned above, actual power production may be 1/2 or even less of the nominal figure. Which panel you choose depends on what you want it to do. If you just want it to keep the batteries topped up between visits to campsites, you may only need a small, low powered model. If. on the other hand, you want to be able to power your vehicle’s or boat’s electrical requirements on a full-time basis, you may need

a solar array consisting of several large panels. Most people in motorhomes and on narrow boats for example, opt for panels between 75 watts and 100 watts in size.

In order to work out what size of panel you need it’s necessary to do some sums. Make a note of the power consumption of all the appliances, which are powered by the battery: lights, TV, water pump, fan, fridge, etc. Then work out how many hours a day each appliance will be used for. Multiply the hours by the power consumption of each appliance. Add everything up to get a grand total and you should have a rough idea of your total daily power requirements. For example: 4 lights @ 12w = 48 watts, used for 4 hours per day = 192 watts 1 TV @ 30w, used for 2 hours per day = 60 watts 1 water pump @ 24w, used for: 20 mins per day = 8 watts 1 cool box @ 48w, used for: 6 hours per day = 288 watts Total daily power consumption = 548 watts

If you’re in Spain and there are 10 hours of bright sunshine every day, a 75watt monocrystalline panel should, in theory, produce enough power to run everything and have power left over to keep the battery topped up. However, the angle of the panel to the sun, shadows, clouds and ambient temperature may reduce the power supplied by the panel significantly. And, in a location where sunshine isn’t quite as reliable, power consumption may exceed power production by a considerable margin. Our advice is to get the biggest panel you can afford and/or fit to your vehicle or boat.

Using Calor Gas Safely - Butane Butane Cylinders 4.5 kg, 7kg, 12Kg & 15 kg Sizes

1. DO when using Calor butane • Do treat a cylinder with care to ensure that the valve is not damaged. • Do when using 4.5 kg cylinders, always use the correct black sealing washer for a gas tight seal. • Do always use cylinders in the upright position unless specifically designed for liquid offtake • Do return cylinders when empty or when not in use for long periods • Do read the instructions and labels provided with your appliance and keep them handy for future reference. • Do keep your appliance clean and have it serviced regularly by a competent person. Not only will this help to keep it safe but also means it will burn efficiently and therefore save money. • Do ensure there is an adequate supply of fresh air in the room whre your appliance is used. If a room has ventilators or grilles ensure these are open. If a room becomes stuffy, open a window or door immediately. • Do try to exchange full for empty cylinders out of doors. A change indoors should only be done away from any sources of ignition such as open fires, boilers, electric heaters, pilot lights, lit cigarettes etc. The appliance must also be switched off and preferably allowed to cool before the cylinder change takes place. • Do be careful when lifting cylinders. Full cylinders weigh approximately twice the net weight shown on the cylinder.

2. DON’T when using Calor Propane • Don’t subject a cylinder to heat as the pressure inside could build up to exceed the safe limit Don’t attempt to unscrew or disconnect a clip-on or screw-on regulator or valve wheel from any cylinder if the flame doe not go out when the regulator is turned off. Leave appliance alight and call your local Calor Gas retailer. • Don’t when using a 4.kg cylinder use the rubber washer from the protective black cap as a sealing washer. • Don’t store or use cyinders in cellars or below ground level. LPG is heavier than air and if there was an escape the gas will collect at low level, can be an asphyxiate, and can become dangerous in the presence of a flame or spark. For the same reason do not store cylinders any closer than 2 metres from untrapped drains, unsealed gullies or openings to cellars. • Don’t attempt to force a regulator of one size on to a cylinder’s valve of another size. If you have any difficulties contact your Calor Gas retailer and have the appliance checked. • Don’t improvise or modify your gas appliance. Always ask your Calor Gas retailer for advice and do not let unqualified people tamper with or

service your appliance. It could become unsafe to use. • Don’t obstruct access to cylinders.

G.P.S. - A Brief Guide

The Global Positioning Satellite network is owned and operated by the American Department of Defence who were only allowed to set it up on the condition that they made it freely available for civilian use too. It uses 28 satellites which circle the globe at an altitude of around 12,000 miles and the idea behind GPS is that at least three of them are visible (although not to the naked eye) at all times, anywhere in the world.

When a GPS receiver locks on to the signal of at least three satellites, it calculates exactly where it is in terms of latitude and longitude and tracks movement. With four or more satellites in view, the receiver can also determine the altitude. Using this information, the receiver’s software then calculates speed, direction, routing and so on, according to the sophistication of the receiver. Accuracy varies according to various factors including, possibly, the security situation but in general, most modern receivers will be accurate to within approx. 50 ft.

Use of the GPS system is completely free with no set-up costs, no subscription and no additional equipment needed. There are many different receivers on the market designed for use in boats, aircraft vehicles, and for walkers. They all do basically the same job: they tell you where you are. All you have to do is decide what additional features you need.

TV Aerials

Unless you watch TV via satellite or cable you’ll need an aerial. These come in various shapes and forms but they can be put into two main categories: directional and omni-directional. Within each of these categories are models which can be used indoors or out. To cut a long story short, outdoor aerials tend to work better than indoor ones and directional aerials tend to outperform omni-directional ones.

Omni-directional aerials are the ones you see on caravans, trucks, etc. which usually look either like a flying saucer or a collection of bent coat hangers. They’re designed to pick up a signal no matter which direction it’s coming from and this is an attractive idea for anyone watching TV in a vehicle because, in theory, you can just turn up somewhere, turn on the TV and be assured that your aerial is receiving whatever signals are coming from the local transmitter. Like anything that sounds too good to be true, however, it is. The reason that houses don’t have omnidirectional aerials on their roofs is that they just don’t work as well as directional aerials, which are pointed directly at the transmitter. Omnidirectional aerials do work and the amplifiers, which come with them, can help to boost the available signal. But unless the signal being received is strong and consistent this type of aerial may not work much better than – literally – a coat hanger.

A directional aerial will always perform better than an omni-directional model but only if it’s pointed accurately towards the nearest transmitter. The problem here is: how do you know where the nearest transmitter is? The easy way to find out is to look at aerials on buildings nearby. Another way is to rotate the aerial until you find the best signal. A good directional aerial is essential if you want to get the best out of Freeview. An omnidirectional unit may pick up some channels but in areas where the signal is weak, it may not get all of them. In some areas, a directional aerial might not receive all channels but you’ll have a far better chance of getting a good choice of viewing.

If all this sounds a bit too stressful, you could always make do with a simple indoor aerial. They’re cheap, easy to use and, perhaps surprisingly, can be very effective. Some have built-in amplifiers and these work even better. Whichever type of aerial you choose, bear in mind that no matter how good it is, if there’s no signal to be had, you won’t get a good picture and you may not get a picture at all. This is one reason why, especially if you travel to out-of-the-way places, satellite TV may be the most suitable way for you to receive TV.

12V/24V Cooler Boxes and Fridges

Whether on a long summer’s journey, parked up for the night or just down at the beach for the day, keeping food and drink fresh and cool when

you’re out and about has never been easier. In fact, with hundreds of cool boxes, cool bags, coolers and fridges to choose from, the only problem is deciding which method of cooling will suit you best

Traditional cool boxes and bags use insulation and ice packs to keep things cool: fine for picnics, as long as the temperature doesnt get too high and the contents only need to stay chilled for just a few hours. For more demanding situations, when ice packs are not available or just for sheer convenience, a thermoelectric cooler box or even a mobile fridge could be just what’s needed.

But what are the differences between thermoelectric cooler boxes and fridges and why do prices vary so widely? In short, a cooler box will simply plug into a 1W or 24V power supply and, using technology, which is also used to keep rocket guidance systems cool, maintain a temperature of up to 30 degrees below the ambient temperature. So, if the temperature outside is 30 degrees, the temperature inside the box will be around 5 degrees — 15 degrees depending on the model.

In hot conditions such as those found during the summer in southern Europe, a cooler box may simply not be able to cool its contents sufficiently but they are ideal for use in average northern European conditions. Cooler boxes are much lighter and so easier to carry around than fridges, making them suitable for picnics and other occasional uses. With some cooler boxes their operation can be reversed and they can be used to keep food warm. Higher prices tend to reflect more features, better performance or lower power consumption and longer life of the components. With cooler boxes, more so than with a lot of products, you really do get what you pay for.

Fridges are more appropriate for conditions where temperatures are likely to be constantly high and where it’s important to be sure that when cold things are put in, they stay cold no matter what the ambient temperature.

There are two kinds of portable 12V/24V fridge: absorption types such as most Electrolux/ Dometic models and units which use a compressor. Absorption fridges are cheaper, very reliable and completely silent They are not usually as powerful as compressor fridges however and some portable models will not reach temperatures much below 5 degrees. Furthermore, they should be kept almost completely level in order to work properly. At more than a 10 degree tilt the fridge may stop working. Absorption fridges require a lot of power when running on electrIcity, as much as 8 Amps on 12 volts and this is why they can usually be operated from a gas supply, as well as on electricity.

Compressor fridges are the ultimate in mobile cooling. They come in a wide variety of shapes, sizes and performance levels and, although not cheap are the best way to ensure the same sort of performance in all conditions that you would expect from your fridge/freezer at home. Models are available which will freeze as low as 22 degrees, cold enough to keep ice cream frozen. Compared to both cooler boxes and absorption fridges, they use little power as few as 12 Amps on 12V in average U.K. conditions and, thanks to modem compressor technology, make hardly any noise. Road Pro have supplied this model of fridge to the Police for storage of D.N.A. samples, diabetics for keeping their insulin at a safe temperature and anyone who needs efficient dependable refrigeration on the move.

In the end, what method of cooling you should choose depends on what you need it to do. Before buying a cooler or a fridge, ask yourself the following questions: how cold do you need to keep the contents? What is the environment where you will mostly be using it? How often will you be using it? What power source will you be using? What internal capacity, will you need, and what external size and shape will be most convenient? When you’ve answered these questions, you should have a good idea of which unit is best for you.