Mono electrical upgrades - how to proceed ?

[Loggo]

A friend an I have very similar boats with a very similar problem. Although we leave our moorings with fully charged batteries during the recent warm weather our cruising pattern of less than two hours motoring and a day mooring is not sufficient to meet the electrical demands of the fridge (light and tv use are minimal) Our problem is in which order should we add enhancements to the electrical system ?
Currently (get it !) we have 60 a alternator and two 105/110a/h domestic batteries .Engine and thruster batteries are separate and not an issue

We are considering :-

Higher output alternator -say 90 a
Larger capacity battery bank - say 2 x140ah
One of mr Sinclairs alternator enhancement jobbies
A largish solar panel

My present reserve is a portable generator but I feel guilty using it near other boats.

Any thoughts would be most welcome as we would like to get the largest benefit first.

 

[David2452]

An alternator booster would obviously be the most appropriate as even if you increase your reserve capacity your cruising pattern does not allow for replenishment. However, why not try to reduce your consumption instead? A few freezer blocks in the ice compartment whilst on shore power and cruising will help keep the inside cool if you turn the fridge off overnight when it will not be opened.

 

[halcyon]

Currently (get it !) we have 60 a alternator and two 105/110a/h domestic batteries .Engine and thruster batteries are separate and not an issue


Any thoughts would be most welcome as we would like to get the largest benefit first.

Check the alternator and battery voltage when charging, how are you splitting the charge to service and thruster battery ? you may well not be fully charging batteries hence limited fridge power.

Brian

 

[superheat6k]

A solar panel approx 1/4 to 1/3 sq mtr will easily top off your domestic set after a few days. Had one on my last boat with no shore power, and always found them well topped up next time to boat.

To reduce night draw install LED lamps in every fitting. As mentioned some eutectic blocks will reduce the fridge load.

 

[Loggo]

Thanks to all those who replied. I do not think the ice pack idea would have much of an effect. My wife never sets off without the 'fridge being packed to bursting and we (mostly) have a night on mains before setting off to lower the temperature of the contents. We generally have low wattage bulbs in place but this is not a big deal at this time of year as we are normally in bed around dark. More important in spring and Autumn but the 'fridge is under far less pressure at those cooler times.
Hakyon - Good point but I do not have the skill to do this. How would I set about it ?

I think the way I will go forward is :-

1.Upgrade alternator (Prestolite seems the budget choice)
2.Alternator booster.
3.Upgrade battery bank to 140 a/h (The batteries will need replacement soon anyway)

4. Next year try a medium sized solar panel it the foregoing has not done the trick.



Have I missed anything ?

 

[halcyon]

Thanks to all those who replied. I do not think the ice pack idea would have much of an effect. My wife never sets off without the 'fridge being packed to bursting and we (mostly) have a night on mains before setting off to lower the temperature of the contents. We generally have low wattage bulbs in place but this is not a big deal at this time of year as we are normally in bed around dark. More important in spring and Autumn but the 'fridge is under far less pressure at those cooler times.
Hakyon - Good point but I do not have the skill to do this. How would I set about it ?

I think the way I will go forward is :-

1.Upgrade alternator (Prestolite seems the budget choice)
2.Alternator booster.
3.Upgrade battery bank to 140 a/h (The batteries will need replacement soon anyway)

4. Next year try a medium sized solar panel it the foregoing has not done the trick.



Have I missed anything ?

You could have a blocking diodes system that is dropping voltage from the alternator, thus reducing the battery recharge level, thus giving you your battery problem. If this is the case you could correct it for £50 - £100 by fitting a VSR, but you need to check voltages, find the problem first.

Brian.