REBrueckner
Legendary Member
- Joined
- Apr 24, 2005
- Messages
- 4,168
- Status
- OWNER - I own a Hatteras Yacht
- Hatteras Model
- 48' YACHT FISHERMAN (1972 - 1975)
When your charging source ( amps) is properly matched to your battery bank capacity (amp hours), and your battery bank capacity to your daily load in amp hours, you can reduce genny run time to a minimum. This is VERY valuable for long term cruising away from shorepower because a balanced dc (battery) system reduces genny run time (and wear and tear), limits noise periods, and extends battery life. It pays for itself in marina fee savings.
Design steps are NOT rocket science:
(1) Determine your daily amp hour load, (say, 150 amp hours, is typical).
(2) Pick batteries (amp hour capacity) of your choice at least three or four times the capacity of your daily load, or more, (This limits daily discharge cycle depth resulting in longer battery cycle life, permits more rapid charging, and daily charging reduces sulphation.) (4 x 150 is about 600 AH, about three 8D's. Four or five is even better.)
(3) Size your charging source to about 25% of the battery amp hour capacity for wet cell, 40% for gel, 100% for AGM. (If well cell, you should charge at about 25% of 600 or 150 amps. AGM's will take close to 600 AH!)
You should be able to recharge from, say 50% to 85% or so in a hour.
Poof: you have a well balanced dc system! Of course you need the genny power to charge at this level, and perhaps power AC loads at the same time (such as a water heater and microwave) if so desired.
One way to help this along: perhaps eliminate electric cooking (a heavy draw) and convert to propane. If you run your genny all day anyway, as for air conditioning, the above accomplishes little.
Design steps are NOT rocket science:
(1) Determine your daily amp hour load, (say, 150 amp hours, is typical).
(2) Pick batteries (amp hour capacity) of your choice at least three or four times the capacity of your daily load, or more, (This limits daily discharge cycle depth resulting in longer battery cycle life, permits more rapid charging, and daily charging reduces sulphation.) (4 x 150 is about 600 AH, about three 8D's. Four or five is even better.)
(3) Size your charging source to about 25% of the battery amp hour capacity for wet cell, 40% for gel, 100% for AGM. (If well cell, you should charge at about 25% of 600 or 150 amps. AGM's will take close to 600 AH!)
You should be able to recharge from, say 50% to 85% or so in a hour.
Poof: you have a well balanced dc system! Of course you need the genny power to charge at this level, and perhaps power AC loads at the same time (such as a water heater and microwave) if so desired.
One way to help this along: perhaps eliminate electric cooking (a heavy draw) and convert to propane. If you run your genny all day anyway, as for air conditioning, the above accomplishes little.
