fridge consumption

[Pennie]

I know this time of year solar power is very limited but I thought "that's OK, my consumption of 12v power is also low." However, in a prime south facing mooring with little interrupted sun light during the useful period and a 300w solar system able to reach 328w during spring, my batteries are almost running flat now.

 

I keep my panels clean and angled during the day to be in prime position. I think just having 2 leisure batteriesare running flat despite just running my fridge 24/7; very occasional water pump; and only the bathroom light 4/5 times an evening means that either my fridge (or something) is using more than it should or I must increase the number of batteries?

 

What would those more knowledgeable than I suggest?

 

Ps (my fridge is one of the newest wacco brand, not certain on the specific model without digging out my receipt or manual, but it's a fairly modern, eco, low energy use model)

 

Pps (it's quite likely I will need more batteries. Currently they are boxed in a metal battery box. How safety should I increase the number of batteries?)

[Richard10002]

With the fridge, my boat uses about 100Ah per day. I'd guess your solar panels are giving you almost nothing at this time of year... Fitting more batteries wont charge them up any better It will just mean they will last a day or so longer before they are flat as well

 

How else are you charging the batteries, other than solar? Engine? Generator? Shore Power? Wind? Nothing?

[MtB]

I know this time of year solar power is very limited but I thought "that's OK, my consumption of 12v power is also low." However, in a prime south facing mooring with little interrupted sun light during the useful period and a 300w solar system able to reach 328w during spring, my batteries are almost running flat now.

 

I keep my panels clean and angled during the day to be in prime position. I think just having 2 leisure batteriesare running flat despite just running my fridge 24/7; very occasional water pump; and only the bathroom light 4/5 times an evening means that either my fridge (or something) is using more than it should or I must increase the number of batteries?

 

What would those more knowledgeable than I suggest?

 

Ps (my fridge is one of the newest wacco brand, not certain on the specific model without digging out my receipt or manual, but it's a fairly modern, eco, low energy use model)

 

Pps (it's quite likely I will need more batteries. Currently they are boxed in a metal battery box. How safety should I increase the number of batteries?)

 

 

I'd say this is to be expected. My solar panels keep the fridge going 24/7 much of the year too, but at this time of year they are useless. The 'rule of thumb' is they give 10% of their summer output in winter, but my personal experience is more like 2.5%. I typically get between 0.1A on a dull afternoon now. Effectively useless.

 

But more batteries won't fix it for you. You need to find another way of charging those you have because you are taking more energy from them than you are putting back. OR a load more solar panels. OR stop using the fridge and keep perishable food outside in the cold...

Or all of the above!

[Tiggs]

 

 

But more batteries won't fix it for you. You need to find another way of charging those you have because you are taking more energy from them than you are putting back. OR a load more solar panels. OR stop using the fridge and keep perishable food outside in the cold...

 

 

Agree with all this. People didn't always have fridges. All your stuff will keep nearly as long outside now anyway. Need to keep it safe from foxes etc though.

[Phil Ambrose]

Agree with all of the above, apart from turning off the fridge, we may live on a boat but we ain't camping. The sensible solution is to have a battery charger run by a small Genny, the 240v supply from that can also be utilized to charge phone and lappy etc . Sound of s Genny buzzing is to me far less obtrusive than a big diesel lump droning away.

Phil

[Alan de Enfield]

I think that every one should accept that Solar Panel output is 'seasonal', and if the output for 6 or 8 months of the year is sufficient, the output for the rest of the year will not be and alternative sources of generation are needed.

 

Its a bit like " In the Summer I fill my car with petrol once a week and I have never run out, now its Winter, I only fill it every 5 or 6 weeks, why have I run out of petrol ?"

[Martin Megson]

I agree with all the above. I have 200 w of solar but in winter I run a small Honda genny for a couple of hours every other day if I'm not cruising. As Phil says it's quieter than running the engine and more economical as it only uses around .25 litres an hour

[Happy Bachelor]

Agree all above. I have 470 watts of solar 3x110 amp batteries and this time of year run the Lump for at least an hour a day and generator for two hours to charge the batts. My daily energy consumption with the fridge is about 80 amps. Don't forget depending on how old your batteries are they do lose their capacity.

last month the solar produced about 10kw this month I doubt I will get 2kw out of them as there has been very little sun.

[MtB]

Agree with all of the above, apart from turning off the fridge, we may live on a boat but we ain't camping. The sensible solution is to have a battery charger run by a small Genny, the 240v supply from that can also be utilized to charge phone and lappy etc . Sound of s Genny buzzing is to me far less obtrusive than a big diesel lump droning away.

Phil

 

 

Very true. My thoughts too.

 

Unless the 'big diesel lump' happens to be a vintage Kelvin. They sound wonderful and I get complaints from neighbours when I turn mine OFF!!

 

Edited November 8, 2015 by Mike the Boilerman

[b0atman]

I remember at my Great grandparents a wooden framed cupboard outside with metal sides full of small holes that they kept food in during the winter, the milk was in a bucket of water under the sink and in the pantry was a marble slab for butter etc.

[MtB]

I remember at my Great grandparents a wooden framed cupboard outside with metal sides full of small holes that they kept food in during the winter, the milk was in a bucket of water under the sink and in the pantry was a marble slab for butter etc.

 

 

Yes I remember that too, and it was woefully inadequate compared to a fridge!

 

The thermal mass of the marble and the water simply stopped the milk, butter etc warming up so much in the heat of the day. Didn't lower the average temperature of the food at all.

 

Another idea to reduce leccy consumption is to put the fridge outside under the cratch cover, if the OP has one. The lower ambient temperature means less heat will penetrate into the fridge and it will need less electricity to stay cool inside.

[Sea Dog]

No doubt the advice you have received is entirely correct. However, you can't quantify it or know even roughly how much you need to supplement your solar with engine/generator running without a battery monitor. Insufficient charging will goose your batteries, too much will waste fuel (and bother your neighbours). Either way, you'll recoup the BM's cost over time as well as gain a warm and fluffy feeling.

[MtB]

No doubt the advice you have received is entirely correct. However, you can't quantify it or know even roughly how much you need to supplement your solar with engine/generator running without a battery monitor. Insufficient charging will goose your batteries, too much will waste fuel (and bother your neighbours). Either way, you'll recoup the BM's cost over time as well as gain a warm and fluffy feeling.

 

 

Excellent advice.

 

The Smartgauge is widely regarded as the best to get and costs £140 (ish). I must get one myself!

 

Where does the board recommend the OP and I buy them? The few chandlers I've tried seem not to have them.

Edited November 8, 2015 by Mike the Boilerman

[b0atman]

putting fridges out side has one draw back in that if the thermostat sensor line is exposed to cold ambient air it can think fridge is at required temperature and not run .

[ditchcrawler]

With the fridge, my boat uses about 100Ah per day. I'd guess your solar panels are giving you almost nothing at this time of year... Fitting more batteries wont charge them up any better It will just mean they will last a day or so longer before they are flat as well

 

How else are you charging the batteries, other than solar? Engine? Generator? Shore Power? Wind? Nothing?

Which of course would be just about 50% of 2 batteries

[Richard10002]

 

 

Excellent advice.

 

The Smartgauge is widely regarded as the best to get and costs £140 (ish). I must get one myself!

 

Where does the board recommend the OP and I buy them? The few chandlers I've tried seem not to have them.

Cactus Navigation

 

http://www.cactusnav.com/merlin-smartguage-battery-monitor-p-11874.html

[furnessvale]

putting fridges out side has one draw back in that if the thermostat sensor line is exposed to cold ambient air it can think fridge is at required temperature and not run .

Other than any potential problems with the freezer side of things (lets talk larder fridges only), surely if the whole fridge is down to the desired temperature, it doesn't NEED to run?

 

Or am I missing something?

 

George ex nb Alton retired

[ditchcrawler]

Cactus Navigation

 

http://www.cactusnav.com/merlin-smartguage-battery-monitor-p-11874.html

Note its + VAT

[bottle]

Fridges and freezers have a designated ambient temperature range that they require to be in, to work correctly.

 

For instance one designed to work in the average kitchen will not work correctly in an unheated garage.

 

The ambient temperature range can be found in the specifications.

[magictime]

I think it's going to boil down to a choice between generating more power through non-solar means (engine, generator), and finding a less power-hungry way of keeping your food and milk cold during the winter months.

 

For what it's worth, the outboard engine on our old boat never generated enough electricity to run a fridge at the best of times and so we made do with a good quality ('Icey Tek' brand) coolbox. This was mainly for spring/summer cruising and used to need a fresh bag of ice cubes from the supermarket every few days, but would no doubt have been a lot 'lower maintenance' through the winter if kept somewhere cool. Obviously it's not as convenient as a proper fridge, but it might be worth considering.

[Richard10002]

Note its + VAT

£126 delivered.

[dor]

Other than any potential problems with the freezer side of things (lets talk larder fridges only), surely if the whole fridge is down to the desired temperature, it doesn't NEED to run?

 

Or am I missing something?

 

George ex nb Alton retired

 

Many fridges do not operate with a thermostat. The temperature control is just a timer thing - turn it up and it runs for more of the time. So if installed somehere that is 15 degrees below what it is designed for, it will possibly get too cold (i.e. freeze the contents).

[furnessvale]

 

Many fridges do not operate with a thermostat. The temperature control is just a timer thing - turn it up and it runs for more of the time. So if installed somehere that is 15 degrees below what it is designed for, it will possibly get too cold (i.e. freeze the contents).

In which case, in cold weather I would switch it off and use it as a posh cupboard.

 

George ex nb Alton retired

[ditchcrawler]

 

Many fridges do not operate with a thermostat. The temperature control is just a timer thing - turn it up and it runs for more of the time. So if installed somehere that is 15 degrees below what it is designed for, it will possibly get too cold (i.e. freeze the contents).

This is something I have thought for several years but never heard anyone else say it.

[Pennie]

Think I will turn off the fridge for the winter and keep everything in a cool box outside. Thank you for the advice and clarification, I knew it was a silly thing to ask about as I knew solar input was going to be low