Rolling.
Are we ready?
M-hm.
OK.
So this is actually a topic that I've
wanted to talk about for a long time because I think it's cool.
Hopefully, other people do as well.
But there was a patron named Steve.
Steven the other day sent an email through and said,
hey, Brian, can you explain to me what an amp hour is,
like what does it mean.
What is the definition.
And I think it's a very common question that
relates to boating and power systems,
so it's a cool opportunity to talk about.
So this is the house battery bank for Delos.
Each one of these is 100 amp hours.
So we have 1, 2, 3, 4 5, 6, 7, 8 batteries.
8 times 100 would be 800 amp hours.
So an amp hour.
What the hell is an amp hour.
It's basically a measurement of charge taken out
of the battery over time.
So imagine if you had our water tank on Delos
is 1,000 liters of water.
If we used 100 liters of water for an hour,
how long would it be before we run out of water?
Would be like 10 hours.
100 times 10 is 1,000.
Well, this is exactly the same.
So if we have 800 amp hours of storage capacity
in these batteries, if we used 800 amps,
we would kill the batteries in one hour.
If we used 80 amps, it would take
10 hours and so on and so on.
So you just do the math.
So what we're trying to figure out here is, of all the things
that we have on the boat, what is the consumption of amp
hours of each device.
So what are some things that we use on Delos?
The refrigerator.
So we have--
I'm just going to put a fridge.
I got that one right.
Good job.
What else do we have?
Toilet.
because that's electric.
We have Mac, and then we have PCs.
So we have Macs, and we have PCs.
For the next part, I got to introduce you
to a really simple equation.
Power, which is measured in watts,
equals current times volts.
If you can figure out the current that everything uses
and multiply that by the time we use it,
we'll end up with the number of amp hours
that we consume every day on Delos.
And this sensor right here is monitoring our DC power.
So it gives us our battery voltage.
It gives us the amount of power we're currently using.
It gives us the amount of the DC current we're using
and the battery state of charge.
So what it's saying right now is pretty much the only thing
that we have on is the navigation system for the boat.
And it's using 2.7 amps.
And we're not running anything else.
I've turned off all the fridges.
I've turned off the freezers.
We have some lights on.
Maybe I'll turn those off too.
So lights and fans are now off.
So now we're sitting at about 2 amps,
which makes sense because it says
we're using 52 watts of power.
2 amps times 26, 2 times 26 should be 52.
So our equation is good.
Because now that we know that we're using 2 amps just
with this turned on, we're going to have Karen flushed
the toilet in the back, and we're
going to see how many amps the toilet uses when we flush it.
Guess-- with the power being put out there.
35.
Volts?
I don't know.
How am I supposed to know?
Trying to explain the equation.
But we won't know until we see the thing.
OK, good.
You can stop.
So it uses 6 amps, just the toilet flushing.
6 times 26.
From 54.
So that's 156 watts.
Now, the whole purpose of this is
to actually figure out the amount of amp hours
that we're using.
How often do we use the toilet?
We say we flush it for five seconds, to flush the bowl out.
Let's say 10.
10 times.
So that's for four people.
That's 40 toilet flushes a day.
Oh, 10 per person.
Wow.
Now, you tell me.
Let's say [INAUDIBLE].
I probably use it like four.
Cans once an hour.
Once an hour?
No.
Between all of us.
Not just me.
No, let's just round up to 30 flushes a day.
30 flushes a day.
Is everybody happy with that, for four people on a boat.
That's a lot, but a family of four dudes.
So 30 flushes times 5 seconds each is 150 seconds.
So if we use 6 amps when we flush it, for 0.042 hours,
we just multiply that.
And so the amp hours for the toilet is to 0.25 amp hours.
The fridge uses 1.8 amps, and we're
guessing, probably that it's running for about half the day
or maybe a little bit less because, at night it's
a little cooler.
So maybe the fridge is running 10 hours a day.
So if it uses 1.8 amps and you run it for 10 hours,
that means it uses 1.8 times 10 or 18 amp hours.
A day.
Right.
So it uses 6.2 amps.
So if we use 80 liters of water today,
this pump puts out 5 liters per minute.
1.64 for the water pump.
So we use significantly more power
on the water pump than the toilet.
Every light on the boat, turn them on.
Yeah, the freezer is off.
On.
Ah.
So each one is like 0.1--
Yeah.
--or so.
I think that's all of them.
All right.
Negative 5.3.
So we're using 3.3 amps for every light on the boat.
So all these things on the boat have
been running off of just DC power, straight power
off the battery.
But if we use anything that's AC, alternating current,
like you'd have in a house, you need to use a power inverter.
So that changes, in our case, 24 volts DC.
It changes it to--
on our boat we're a European boat,
so it's 230 or 220 volts AC.
So what does that mean?
That means with just the inverter turned on,
even if we're not using anything,
it's using 0.3 amps, just for the inverter.
So 3.6 amp hours just because it's not 100% efficient.
It's turned on.
It's probably generating a little bit
of heat in the engine room.
Right.
And this computer is turning on right now.
Whoa.
Power sucker.
So if we're using 4 amps times 4 hours, that's 16 amp hours.
Let me shut mine down, and we'll start passes.
It's using like 1 amp, right?
Does that look right?
Do you need another reason to [INAUDIBLE]??
[INAUDIBLE], people.
So the PC, the super brick, the supercomputer uses 4 amps.
[INAUDIBLE] Mac device is using 1 amp.
Macintosh.
It does the same thing, and it's a fraction of the size.
I don't know what the deal is.
Whatever.
Let's say you also use it four hours a day.
[INAUDIBLE] uses her computer like six.
Six hours a day.
Let's go five.
So we're going to put 5 amp hours for the Mac,
and 16 amp hours for the PC.
That's just embarrassing.
Whatever.
The fridge?
18 amp hours; the toilet, 0.25 amp hours; two Macs on board
are using 10 amp hours, so times 2 equals 10.
Two PCs are using 32 amp hours.
Water pump, 1.64; freezer, we'll just
say 24; all the lights, 13.
What else we got?
Ice machine, 24; inverter, 3.6.
So let's just add these things up real quick
and see what we come up with.
There's obviously a lot more things, and when we're sailing,
we're using more because we have the autopilot.
We have all the other instruments on, GPS
and other navigation, but that's a whole different ball game.
But we don't usually have all the lights
on during the day and all these things.
So we're doing like an add-anchor configuration
here because we can also do the furlers.
We can do the bow thruster, we can do the anchor windless,
all of these things.
You have to think of everything, but we're just doing
the normal add-anchor stuff.
130 amp hours is what we use in a normal day
if we're editing videos and stuff.
If our capacity is 400 amp hours--
Hey, wait a second there, Captain Brian,
I thought you said we had 800 amp hours on Delos.
1, 2, 3, 4, 5, 6, 7, 8 batteries.
8 times 100 would be 800 amp hours.
Delos has a 24-volt system, but the amp hour ratings
supplied by the manufacturers is for a 12-volt battery.
If we use this equation to calculate the watt hours
for the battery bank, we can show
that 400 amp hours at 24 volts is exactly the same capacity
as 800 amp hours at 12 volts.
130 divided by 400.
So we're using about 30% of our total capacity every day.
130 divided by 200.
So we're using 65% of our usable capacity every day
just based on those numbers.
So what's the difference between total capacity and usable
capacity?
Well, it turns out if you have lead acid batteries,
the total capacity and usable capacity
are two very different things.
If you have 400 amp hours of capacity like we do,
only about half of that is usable.
So if you look at this, if this scale is 400 up here,
0 here, this is 100% charged.
Right about here, we never try and take our batteries
below that.
And this graph goes like this.
It's an exponential curve leading down.
Now, the reason why that's important
is because the lower you cycle your batteries the less
cycles you get out of them.
So if you're hard on your batteries
and you're always taking them all the way flat,
they're going to last something like 200 cycles.
And if you're cycling them once a day,
it's 200 days they're going to last.
Not very long.
Whereas, if you only take them down to 50%,
you can get something like--
I don't remember what the number is.
I think it's like 1,000 cycles.
Well, actually, we'll try and grab a real chart
from a battery and show exactly what it looks like.
So that's the trade off.
So if you only let your batteries get down to 50%,
you can get them to last a lot longer.
But the nice thing is we have solar pumping in power.
We have wind pumping in power.
And so that's why some days we can
go without running a generator or most days,
we can go without running a generator.
And certainly, if we're not editing a lot,
Delos can sit here indefinitely just off solar and wind.
I think that's probably a whole other video in itself.
All right, for sure, this is going
to be one take this one time.
All right.
Hey guys.
Thanks for watching.
I sure hope you learned as much as I did.
If you'd like the video, be sure to give us a thumbs
up because it helps us to know if we should make
more of these kinds of videos.
Any questions or comments, just pop them below.
I'll do my best to answer.
Ciao.