powering up the portable freezer

I've had an evakool for 8 years now and it has been excellent.

I did an exercise a bit like what you want a while back and was going to buy 2 X 80 watt panels. Currently have a Sealed lead Acid 100 AH battery but can't afford the panels yet.

I can get about 3 days out of the battery before it needs charging. Even if you do buy the panels there are times when you won't get any sun, or enough sun so would have to be prepared to top up your battery some other way if needed.

I use a cheap genny with a charger at the moment but find I hardly ever use it as I seldom camp up for more than a couple of days without power.

I had a Waeco 45 abd sold it as the battery management and costs of solar were going to be too much. Am organising a 3 way fridge and will camp in the bush using gas. Easier, cheaper and works the same. Have the dual battery in the truck so can keep the temp up while travelling.

We are doing what you intend to do right now. We run a 50l Waeco as a fridge and a 40l as a freezer. We have no generator to run as backup. The last couple of months have been a good test for our setup as we have been at NE NSW and SE Queensland while all of this this rain has been falling.

We run two 123W Sharp solar panels and 300A/H of storage. Under sunny conditions we can run the fridges and a couple of 12V fans, lights and two laptops day in and day out. Generally our State of Charge of our batteries drops by about 18% overnight. This means that we could run the two fridges and not much else for about three days without any sun. (I don't want to discharge more than 50% as the wear and tear on the batteries is too great.)

What I've found is that even on cloudy days we get some current out of the panels. It varies but often as not, over the whole day we at least make enough power to cover the freezer operation. The end result is that once only did the state of charge of the batteries drop to my arbitrary cutoff point. We then got a couple of good days where there was plenty of sun and our solar regulator went into Boost mode and we got back to 100% capacity.

Worst case is that I could charge the batteries with the vehicle but we never got to the stage where I thought I should do it. If you are like us and will being travelling Oz in such a way that you will hopefully have good weather most of the time, then a setup like ours could be OK for you.

The catch: we are going to be travelling indefinitely, so we though that the expense was justified when spread over a long time. If you only intend to travel for a year or so, it might be a lot of dough that you'll outlay and then either have to sit on the goods or try and sell later to recoup.

To give you an idea, the two solar panels were about a grand each. The regulator was $300.00, the batteries are AGM and were nearly $500.00 for the lot. We purchased a three-stage battery charger for when we do have mains power available and it was all-but $500.00 as well. I also used very heavy cables for everything - the largest size that would fit into 50Amp Anderson plugs for the solar panels and even heavier for connecting the batteries together and to the solar regulator. You could buy a lot of gas with that kind of money.

The benefits of doing it our way are that we have no ongoing operating costs and we don't need to carry a generator, fuel, oil, spares etc. Solar is also totally quiet. The drawback is the initial outlay. You would not have to go to the extremes that we did but from experience I know that you would need at least two 80W panels and to be safe, at least two 100A/H batteries. Remember that the more deeply you discharge batteries, the shorter their life expectancy becomes. I'm aiming the get about seven years out of ours by limiting the depth of discharge to no more than 20%. You can't avoid buying a solar regulator but there are cheaper ones than the one we got.

It's up to you but at least you have a case-study now to give you a starting point.

Cheers,

Russ.

hi again, while we are on the subject when joining up the deep cycle batteries do they have to be the same amps? as we have already got a 40a/h and wondered if we can buy say an 80 a/h and connect them together.
thanks a lot for the import so far it's certainly food for thought and now getting our brain thinking of the 3 way again.
thanks again Chris.

Chescold, green ($1000) or blue ($1300). Unless you are prepared to spend lots of cash on batteries (which wear out and/or fail) and solar panels or are prepared to run a gen for some time each day then 3 way fridges are unbeatable for stays of more than a few days in the one spot.

My blue Chescold is currently sitting at -19C (26C ambient in my garage) and held -12C and better on the 40C+ days we had last month.

Mike Harding

hi again, I've done a bit of checking up in previous post about the chescold and kept seeing that they can run for around a month on a 9kg gas bottle the today i found a few that said they last 2 weeks and 2 days as there is quite a difference can anyone tell me how long a 9 kg gas bottle lasts using as a freezer.
thanks again Chris.

Chris,
first things first... the FRIDGE
Best "performance" results come from a fridge with full length and full width cooling plate area, this will cool down much quicker than a smaller plate which is set in one end or one side and end only because the refrigerant is cooling the entire area at the same time, not from just one end or side.

Solar and Batteries
You need to know the total Amps you will use in a 24 hr day.

I don't have to guess at the size and capacity for Solar panels and Batteries, as I use 2 x 100+ ah AGM batteries and 200+ Watt Solar system, the battery system * never * gets below 12 Volts running a fridge that draws 8 Amps.

That's a starting point, you will get away with lower capacities if using a fridge with a smaller power draw.

Solar REGULATOR
get the best - forget the rest lol

Mainey . . .

Gday Chris,
Theres plenty of good fridges out there. My view is:
- The only reason to get a 3-way is if you plan on staying camped in the one spot for a week or two at a time, and not be using your vehicle. They are finicky, don't work well in hot South Australian weather, have to be dead level (need spirit level) etc On 12volts they will use a minimum of 10amps per hour.

- You left Engel off your list, but I use two of them - sometimes one as a freezer, but mostly use them as 2 fridges (since I bought my own vacuum packing machine). I monitor the temp inside each, and like the way the Engels are so well regulated - you have infinite adjustment of the temperature, so the one with meat gets set to exactly 2 degrees, while the one I use as a cooler gets set to 5-8 degrees. If I use one as a freezer, it sits on about -18degrees. I have used it as a freezer in desert country in 45 degree heat and it kept freezing at about -8degrees. Snowys have the 40l Engels on special at $1050 for the 40litre with inbuilt temp gauge. Max power consumption is 2.5 amps per hour. Any compressor fridge will use heaps less power than a chescold 3way.

G'day Chris

I don't know about your circumstances but do you need a freezer at all? We go to Cape Leveque each year for a month and stay in a beach shelter without power. We get a fair bit of meat cryovaced in Broome before we go up and sometimes there is some left when we get back and still ok. There is only 2 of us to cater for. We use a 40 litre Engel, dual battery 50 amp hr and 2 x 40 watt solar panels. We never run out of power and can have a couple of cold beers and a bottle of bubbly each day.

You should look at the Engels also before you make your decision on a fridge. Most people we encounter seem to be abandoning other brands and most now have Engels in the back. One particularly irate gentleman at C L had two units of one of the brands you have mentioned and both broke down. It was good for us because he was a good fisherman and had to give his catch away each day. Another guy, also at CL couldn't beleive how much longer he could get out of his battery when he replaced his same brand fridge which broke down with an Engel.

I know there is a lot of hoo/ha on this forum about fridge brands but my opinion is based on the experience of 6 trips since 2001 and no fridge problems.

Cheers

Peter

hi again, we did think about an Engel but in searching out advice on all the different fridges we were told by someone that has a great deal of knowledge not to go near a new Engel with a 20 foot barge pole but if lucky enough to find on older one to grab it and never let go. the reason for this is now they seem to be made with less insulation and that not to leave the cover on to long because of condention is causing them to rust out, ie- one was returned less than 12 months old and totally rusted out. I'm not going to say who this was that told us but they had no reason to lie or stretch the truth, but as I'm sure you can understand it's a lot of money to us and we are trying very hard to get it right the first time, hence all the questions- experience is worth it's weight in gold.
and to answer do we need a freezer, well we are planning to do quite a lot of travelling and this would allow us to stockup were suitable, we have bought a vacuum sealer (not quite as good as cryovacing i know) but it still helps aswell as saving heaps of room.
Chris