Electric Power for your Motorhome / Batteries

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Coffeemaker in a motorhome

As we have not been able to travel this year as much as we usually do, and there is therefore not really a lot to tell you, we thought we would write a newsletter about electric power for your motorhome.

If, when you travel, you always use campsites and always connect your motorhome to the mains then you really don’t need to know a lot about this and on our tours most of the time there is electricity available. However, on some tours, we do ask that you can “survive” without mains electricity for one night, particularly when, for example, we have a wine-tasting and stay directly at the vineyard, where an electric hook-up might not be available. It is therefore important to know how much power is available to you from your leisure battery.

Define your daily electric demand
The first step is to estimate how much electric energy from your batteries you would typically use in 24 hours. You need to think about which electric appliances you use and how long you use them during the day. Typical appliances are lighting, heating (also to circulate the heat when using gas), the fridge (especially if you have a compressor fridge), radio, TV, chargers etc which normally can be used with your 12V battery. To use other appliances needing 240V, eg. toaster, kettle, coffee machine etc. you will need an inverter.

The second step is to look up the wattage of these appliances. Watt (W) divided by the voltage (V) gives you the electric power in Amps (A), i.e. W/V=A. The resulting Amperage multiplied by the usage in hours gives you Ah, which is the unit of your battery capacity. For example, if you run four 10W LED lights (40W/12V=3.3A) for two hours, you will use 6.6Ah during a day. If you run 240 V appliances on your inverter, for example a toaster that uses 800W then you use 3.5A (800W/240V=3.5A). But as you would only use a toaster for a short time e.g. 5 minutes, the Ah would only be 0.3Ah during the day. Adding up just these two devices you will have taken 6.9 Ah out of your batteries.

Available battery capacity
If we assume you have a regular 80Ah Lead Acid/Gel or AGM battery, you should not ever use more than 50% of the capacity, as this would negatively affect the lifetime of the battery. This means in reality that you only have 40Ah available. If you have a LiFePo4 (Lithium Iron Phosphate) battery you can use almost the full capacity of your battery, so a 40Ah LiFePo4 battery would give you the same capacity as the regular battery in our example. LiFePo4 batteries are also much lighter than standard batteries, which can be an advantage, especially if you are close to the maximum payload of your motorhome. Unfortunately, this type of battery is still quite expensive.

Necessary battery capacity
If your daily demand is greater than your battery capacity, for example a daily demand of 45Ah and an 80Ah regular battery, you are unlikely to be self-sufficient for one day and could end up with a flat battery. To avoid this, you should invest in a higher capacity battery or an additional battery to increase your capacity. But keep in mind you can only add the same capacity battery to your existing one and ideally both should be of the same or similar age.

If your daily demand is below your battery capacity, you are fine for one day off grid – but you should always have a certain margin of security in case your demand is higher than usual. When you know an EHU may not be available at the next site, make sure your battery is charged beforehand by driving a certain distance during the day allowing the generator of your engine to charge the leisure battery. Alternatively, you can top up your battery by using a petrol/diesel generator or by having solar panels installed.

We hope this gave you a first insight into the power supply of a motorhome. For any work done on your motorhome electrics, always consult an expert!

As you all are aware, we had to cancel all our tours this year and many of our customers who had booked a tour with us instead decided, understandably, to holiday in the UK. Two groups of our customers who have now become firm friends after travelling with us used the opportunity to organise reunions in Malvern and Moreton-in-Marsh. Unfortunately, we were not able to join them but have heard that they had a great time and more memories were made. One of the couples, who have already travelled with us on 3 occasions but always in a rented motorhome were even able to surprise the others by arriving in their first own motorhome. So we can now proudly say that we have converted the first caravanners to motorhome travel :).

We are very aware that many of you cannot wait to travel again normally next year and would like to thank everyone for all the bookings we have already received for the 2021 travelling season – many of our tours are now close to being full. Unfortunately, due to the Covid-19 situation, we will not be participating in any shows this year in the UK. The next opportunity for you to meet us in person will be at the Caravan, Camping & Motorhome Show 2021 which we hope will take place as normal in Birmingham in February next year. However, if you are interested in our tours or would like to chat to us in person, we would be very happy to give you a call or talk to you via Skype or FaceTime, just send us an email and we will call you at a time convenient to you.

If you are interested in a specific tour for 2021 and would like more information visit the detailed tour pages on our website:

Springtime in Holland
Sat. 10th April – Sat. 24th April
Impressive Italian Lakes & Cities
Sun. 9th May – Sat. 22nd May
Picturesque Provence
Sun. 23rd May – Sat. 5th June
Discover Denmark
Sat. 12th June – Sat. 26th June
Stunning Norway
Sun. 27th June – Sat. 17th July
Amazing Alpine Roads
Sat. 28th August – Sat. 11th September
Captivating Croatia
Mon. 13th September – Sat. 2nd October

For an overview of all the dates and prices download the PDF: Touring Season 2021, Overview Tour Dates and Prices on the main page of our website.

If you have any questions, or require any further information, please do not hesitate to contact us by e-mail, or just give us a call!

Stay safe.

Audrey & Michael