Charge your phone (and everything else) when camping with these pointers from Steve Bain

In today’s world even when we escape from it all, we like the option to remain connected. Additionally some of the comforts of home can make your time away even more enjoyable. Fortunately the modern campsite has the option of being ‘electrically powered’.

Do we need a bigger charge?

Just to see if it could be done, I set out to run an Engel fridge and charge my mobile phone using the power from a car with a single cranking battery and no other power inputs. For the entire weekend the fridge was connected to a cigarette lighter socket while camping. The fridge has a cut off that attempts to halt power drain should the car’s battery become too low.

The phone was charged each time it went flat. The phone remained connected to the internet all weekend and internet use was quite high. At the end of the three-day long weekend, you could have predicted it ‑ the car wouldn’t start. Its cranking battery was ‘a flattery’. That is, the car’s battery was flat. I concluded that we needed more charge.

Basic power

There are three chief power sources ‑ the car battery system (with a dual battery system), a solar panel with regulator and a fuel driven generator. Luckily they can all work together.

Smart solenoid isolator

In a vehicle’s dual battery system, a solenoid isolator switches the current from your engine’s alternator to one battery or the other. A smart solenoid priority charges the main battery and determines when the cranking (starting) battery is full and it then switches the charging into the auxiliary (deep cycle) battery. Some set-ups allow you to link both batteries for high-draw situations. They may also give you the option of jump-starting should your starting battery fail to turn the engine over.

DC-DC charger

A DC-DC charger is used in multiple-battery systems (dual batteries, but think ‘three batteries or more’). The DC-DC charger monitors each battery’s charge, voltage, construction type as well as the engine’s alternator output and ‘tops-up’ the batteries while maintaining priority to the main battery. A big advantage of the DC-DC charger is that they generally afford quicker charging especially when your engine is idle. They can also accept solar panel inputs into their charging system.

Portable solar panel

More than 20 years ago our camp had a fold-out hard-framed double solar panel that we set up by day to charge a deep cycle battery. By night we hooked up this battery to run our lights. Another solar panel topped up the battery that ran our portable 12V fridge. Solar power systems have come a long way since then.

As a general guide, a 200-Watt solar panel will keep a 100Ah to 120Ah 12V battery (deep cycle) going if the solar panel receives six hours or more of sunlight per day. This will be enough to run a large 60-litre Engel fridge for a week. The caveat being that the more lights and other draw that you take from the system at night, then the greater the risk that your battery will struggle and your fridge may cut out. When using a basic system I employ a triple panel fold out 100-Watt model and I tend to keep the fridge circuit independent from any other items that draw current/power.

It is worth noting that any charging spikes will destroy your storage battery. Hence a regulator is incorporated into the system to control the flow of electricity from the solar panel to the storage battery. Some DC-DC chargers have built-in regulators for the solar input. As you can see, designing your system when you purchase components to allow for growth/expansion will allow you to add input and storage options as your budget permits.

Somewhere along the way, the battery became a ‘powerpack’. Essentially a powerpack is a battery box with outlets for 12V, USB and in some cases 240V connectivity. An advanced powerpack may even have a built-in charging system that connects to either solar or a vehicle DC 12V socket. These powerpacks have proved to be entirely satisfactory for long weekend trips. Provided of course the storage battery in the powerpack was pre-charged via AC 240V before leaving home base.

Storage batteries

Deep Cycle ‘wet cell’ (wet lead acid)

At a price point of $300, wet cell deep cycle batteries are the base level option for storage systems.

There are also ‘Gel’ batteries, but they are an option for specific circumstances.

AGM (absorbed glass mat)

At a price point of $500, AGM batteries charge faster than ‘old school’ lead-acid and AGMs don’t give off harmful gases. It is generally accepted that the most economic and practical depth of discharge (DoD) for an AGM battery is 50 per cent. In comparison, Lithium-iron-phosphate (LiFePO4 or LFP) can tolerate a much greater DoD.

Lithium

At a cost that enters into the thousands of dollars, large lithium batteries last the longest (all other things being equal) and are considered the top shelf option for storage in an electrical power system.

Solar charge your phone (and everything else)

Some say the latest and greatest solar panels coupled to an intelligent control management system almost make the noisy generator obsolete. While solar power is another matter, let’s briefly look at an example of a top shelf system set up in an off-road trailer (or van/4WD).

Inputs into the solar power system include:

1. A bank of solar panels; to charge from the sun.
2. An Armstrong Plug; to charge from the car as the trailer is towed along.
3. Optional 240V input; which can be from a generator. Use 240V to fully charge the storage batteries before you leave home. As well you can use the 240V option at van parks and the like as you make your way along on your travels.

These inputs charge the storage battery/batteries via the system’s control unit. Lithium batteries are the ultimate ‘power’ storage unit, but they do come at a price. Expect to pay a few grand for your lithium batteries. At about half the price, AGM batteries are a popular alternative. The big advantage of lithium batteries is that you can run them down to about 20 per cent remaining capacity. Typically you wouldn’t run your AGM batteries down further than 50 per cent. In fact, being even more conservative will give your AGMs longer life expectancy.

The ‘intelligent’ set-up may include a control panel that reports on the status of all items connected into the system. The control panel can be used to manage items such as a fridge and the control can be used to remotely turn them off and on. You can even acquire an app that allows you to wirelessly drive all the functions of this control panel from your phone.

Such a system can run your fridge, LED lights, USB charging ports, cigarette lighter sockets and you can charge your phone via either the sockets or USB outlets. Yep, that’s the same phone that you will use to control the entire system.

These systems can be built into your vehicle and/or your off-road camper trailer. If creating such a system into your vehicle, consider having the battery and controller built into a sliding drawer system. I’ve seen solar panels permanently mounted to vehicles and trailers. Alternatively the panels can be portable. Expect to pay $300 to $400 for a ‘flexible’ 100W solar panel. Ingeniously, some boats and bull bars have them removably mounted into rod holders.

Generators

The subject of fuel-powered generators is a broad topic when you consider the major types and choices. And that’s before you work out the size of generator that you need. This calculation is based on the continuous/running power requirement of each item as well as start-up requirements. A fridge may run at 200 Watts, but require a max load of 600 Watts surge to start up. A small 2.5 kVA inverter generator is typically suitable for running lights, a fridge and a heating/cooking appliance.

The traditional question has always been petrol versus diesel versus lpg. The modern question is whether or not to plumb for an inverter generator model or a silenced option or just the conventional version. If it’s a small lightweight package that you want to use around camp, especially if you wish to run home appliances and/or items with microprocessors like computers and phones, then an inverter generator is probably the preferred option. If it’s worksite type power that you want then a conventional generator is likely to fit your needs. You can even ‘piggyback’ two generators together (for example, yours and a mates) in parallel using factory accessory ‘Parallel Cables’ that are sold separately.

The engine of an inverter generator is connected to an AC electricity producing alternator. Then a rectifier is used to convert the AC power to DC and capacitors are used to smooth it out a little. The DC power is then ‘inverted’ back into microprocessor friendly AC power at the desired frequency and voltage. They produce a pure sine wave which is perfect for use with sensitive electrical equipment such as TVs, laptops, tool battery chargers and other consumer electronics. Silent type inverter generators are specifically designed to keep noise to a minimum. Fuel efficiency and run time per litre is also better.

These days the consumer also has the choice between budget ‘home-brand’ models to top of the range products from motorcycle, outboard and mower engine companies. At my local hardware store the budget brands offer 12-month warranties, Ryobi models have a two-year warranty while Yamaha as well as Briggs & Stratton have three-year warranties on their ‘camper’ sized models.

It’s a tough choice to determine if you wish to pay for the warranty peace-of-mind. We’ve all heard of the expensive item that failed a week after the warranty expired. And there’s a similar number of urban myths of less expensive models that never lasted the 12-month warranty period and the customer kept getting a replacement model before the holidays.

Back in my product testing days, there were some good and bad batches of the cheaper models in most lines. My advice is to give the cheaper option a go, but make sure that you purchase from a store known for customer support. If the cheap model fails you (and your usage regime), then try for a store credit and upgrade to a top shelf model.

Choosing a generator

Selecting a generator that’s best suited to your needs is an easy process that just requires following these measures:

Step 1: Determine the combination of equipment and/or appliances that you will want to power/charge at the same time.

Step 2: Table the start-up power use and running power usage (Watts) for each product.

Step 3: Add the total power usage for the start-up and the running, then add an extra 10 per cent as a safety buffer to both figures.

Step 4: Choose a generator with rated (running) and maximum (start-up) power levels that equals or exceeds your two totals.