batteries traditionally were looked at in terms of cycles. A 100AH battery
cycled between 50-80% would last for so many cycles. This was because charging
was done with the engine
, and that was kept to a minimum due to cost, noise
, vibration ect. But the question in my mind is
"is this really the way to look at it today?"
Most cruising boats will have a number of ways to charge the batteries, or to run straight off the charging
can supply most if not all of the power a typical boat would use. For instance, I have currently 2 100 watt solar panels
, but plan on adding 2 130 watt panels
for a total of 460 watts, plus a wind generator
. This combination should make our boat run off alternative energy completely, or mostly so when the wind
and sun cooperate. When they don't the alternator
on a engine
, or a generator
, either gas or diesel
will kick in to fill the gap.
So what really happens at the battery
level when talking about cycles, when this occurs? I ask because, it will mean a big difference when talking about when to change the batteries.
If most of the load is handled by the solar/wind setup, how much does the battery "CYCLE"? If one were to start with a fully charged battery, and made sure to fully charge it say once per week or month, wouldn't the battery just act as a shock absorber for the electrical system
most of the time?
What would that do to the battery's life span, either FLA or AGM
? And which type would be better to handle that load in terms of life expectancy and performance in cost vs AH vs total life expectancy?
What other factors are there to be considered ?
This is more than just a exercise to me. The savings in battery's and replacements
can be considerable. For instance, I used to have a 800 ah bank, but now expect the same performance with 500 AH or less. at what point would the system be under powered?
I don't have the real life experience, and will not be able to long term cruise
for more than 3 weeks or so for 10 more years, so mostly I will be hooked in to the dock
most of the year, where a small bank would be fine. But for those times when on vacation
for 3 weeks, and when I can cut the cord and cruise
full time, this is my question.
People that are out cruising at using a similar setup, I would be interested in hearing what you have to say about this.