I've been thinking about batteries and electrical use. I'm starting an energy audit, that is a list of my 12 volt power users and their amp/hour draw.
Has anyone done an energy audit? If so please share and please share how you arrived at your numbers.
As I'm most concerned about use at anchor my list will include LED anchor light, fridge, Keurig coffee maker, cabin fans, possibly Engel freezer and more as I think about it.
Thanks,
Jim
Jim
These links may help you develop a budget
https://c34.org/bbs/index.php/topic,9361.msg69541.html#msg69541
https://c34.org/bbs/index.php/topic,2199.0.html
but basically just start a spreadsheet of every usage you have, amperages, hours on-time during one day.
For each use
Amp x on-hours = amp-hours usage for one day. Sum them all.
The other side of the budget is more involved; e.g., anticipated engine run time per day, alt output. # days between shore power charging (cruising or on a hook), solar, etc.
You're probably not going to change your alternator (or maybe you are considering that?) but the key to balancing your budget is meeting the amp-hrs demand by balancing that against the variables on the supply side of
- Shore charging
- Engine hours
- Alt output
- Solar charging
- Bank capacity
Demand A-Hs = AHs replaced by
Daily Engine supplied AH
+
Daily Solar AHs (if any)
+
Daily Shore AHs (if any)
The Bank capacity has be enough to either/both:
Provide the demand before the daily replenishment is complete
OR
Provide enough to make up any deficit in replenishment until back on shore power.
Jim, Here's a copy of what Stu did once upon a time. I did one also, but can't find it :shock:
Jon's right, that the one I did. It's in the 101 Topics, Electrical Systems, Energy Budget.
Here are a few sample spreadsheets I uploaded -- from simple to complicated, that one can modify to suit oneself:
https://c34.org/wiki/images/c/c4/Energyplan_0.xls
https://c34.org/wiki/images/b/bb/2012_Sample_Energy_Budget_0.xls
https://c34.org/wiki/images/8/8f/Energy-Calculator-4.xlsx
Thanks to everyone. I should have know that information would be here. Good information and a fine start for me.
Jim