Solar Upgrade Part 3: a 12 volt audit

When one gets a new gizmo, there is a strong tendency to gravitate towards using it all the time...it's only natural. I would have to say that the Trimetric has had a bit of this effect on me...I just have to press that little button to open up the new world of information it has to offer. This is not a bad thing mind you, I have a much better understanding of what is going on with the state of our solar/battery setup than I ever did before.

Once I got past the fascination with the raw data, it was time to put it to use to figure out exactly what each 12 volt device in the Alto costs, in terms of impact to the battery. Energy conservation while off grid is a bit of a pursuit of ours, so knowing what the real loads are will be great. So I began an energy audit, and along the way, learned a little bit more about how some devices actually work.

First I put together a list of the devices that run on 12 volts, or have a 12 volt component in their operation, such as the 2-way fridge. It may be propane and electric, but the overall operation is controlled by a 12 volt circuit board. Same goes for the water heater. There are a surprising number on board, 19 unique devices in our Alto, not double counting any of the similar light fixtures.  Once I had the list, I then set about to determine the amp hour draw of each one.  This involved turning devices on one at a time, and recording the draw as measured by the Trimetric.

With the display off, the draw of the Trimetric is .01 amps. This came right from the spec sheet, as with no display, how would you get this info? With the display on, the draw is .03 amp/hr. This became the phantom draw to be removed from each reading taken. Next up were the detectors, of which our Alto has the two separate units, LP & CO. As they are both on the same circuit, it was easy to find the combined draw. I might add that all this detective work was done well after darkness had fallen. I wanted to completely eliminate any residual power generation from the solar panels.  The amp/hr calculations done by the Trimetric are based on what is going in & out of the battery. If there is a bit of solar amps going in, then the reading of a device’s draw will be skewed by this positive value. This also fluctuates, as the Trimetric is sensitive enough to pick up the solar output changes caused by even a tiny little cloud.  After dark, I know the readings are truly for the device draw, with no other influences.

From there, it was just a matter of putting the various devices into use one at a time, and watching the Trimetric calculate the negative impact on the battery. Pretty straight forward stuff, or so I thought. I had assumed that once the detectors were on, that was the draw. Not so. While I was finding the draw for one of the LED lights, I saw the amp display move from a stable value, and jump up a fair bit.  There was nothing else on, other than the detectors, so it was a tad puzzling. A bit later, the draw dropped back down to what it was when the light went on.  I turned the light on and off, and monitored the draw further...sure enough, up it jumped again. I timed the on/off cycles. It was soon clear that one of the detectors was "sniffing" the air on a regular 1 minute on, 1 minute off cycle. Based on this, the phantom draw of the detectors was certainly more than I first recorded, and you would be surprised how this changes the calculations over a 24 hour period. The fridge has a cycle as well. There is the control board, and then when the fridge is called upon to cool, there is a little solenoid that opens to allow the propane to flow for the cycle. Holding that solenoid opens makes up the bulk of the draw, and needs to be factored into the amp/hr cost.

Once everything was mapped, I created a little spreadsheet (of course) that would calculate the draw of each device, over different periods of time. Anything with a phantom draw as well as a functioning draw is calculated over a 24  hour period, and this required some adjustments to blend the amp/hr rate. Yes...this is all very geeky.

The chart is pretty interesting, especially when you start to play with the amount of time that a device is running in a day. Take the water pump, a huge amp hog, but then look at how long it actually runs in a day. Even including the possibility of a Dale outdoor shower, would that pump run 10 minutes, 15 perhaps, in a day. This works out to about 1 amp a day. Now look at those little detectors, no motor in them, yet over the 24 hours they are on, they eat over 3 amps! Now who is the power hog??? But that's not to say those are not worthwhile amps, and certainly not going to try to save any there.

When trying to figure out just how many amps were being used in a day, I think there are a couple of groups, what I call the driveway and camping core draws. These are consumptions that are just simply going to be there, regardless. The driveway consists of the Trimetric and the detectors, and over a 24 hour period, adds up to over 3 amps. I've heard some people pull the fuse on their detectors at times, but I'm just not comfortable with that, even if it is just simply sitting there, waiting for the next adventure.  The core camping draw are the same devices, but adds in the fridge and water pump. If you are out, you are pretty much using these, and they are pulling amps out of the battery. I'm sure you could find some savings if you are able to adjust the temp of the fridge, or even turn it off, but for the sake of not getting too crazy with the calculations, I'm assuming a relatively normal manner of operations.

From there, I used this core group and came up with a couple of scenarios, to try and estimate just how much we may be using. These definitely lean towards conservative consumption. You can see how it could be very easy to use up all your available amp hours, as devices go on, it add up quickly. If you are out for a while off grid, you also have to keep in mind that you need to replace the amps you take out, and this requires good solar conditions...which means lots of sunlight. As well, from what I have read, the amp hours come out of a battery a lot easier than they get replaced, which is probably the main reason I upgraded the solar controller, to make sure this process was as effective as it could be.

So after a few outings with the new solar components, am I satisfied it has been a good investment?Most definitely! Not only do I know exactly what is coming and going from the battery, I know that the battery is being charged as effectively as possible. Can I quantify this. I think so. The battery recovers its charge a little faster, from the parameters programmed in it is certainly fully charged, and when I initiate an equalization phase, I know I am prolonging the overall battery life as per Trojan specs. Sounds pretty good to me.

I would certainly recommend the additional of a Trimetric monitor for those planning on a lot of off grid camping. It really helps you know exactly what the battery state of charge is.

Have a look over the chart, and although some of the equipment in the Alto has changed over the years, it will give you a high level picture of how amp hour usage can accumulate over the course of a day, and how your own camping style will impact this.  The raw numbers are there to help you calculate your own scenarios. Pretty interesting stuff.


Item Device Phantom
Draw
A/hr
Draw
Approx
Mins
Day
Approx
Hrs
Day
Daily
A/hrs
Notes
1Trimetric
(display off)
0.0100.010144024.000.240
2Trimetric
(display on)
0.030300.500.015
3LP/CO detectors
(individual units,
same circuit)
0.09
(0.18 sniffing)
0.135144024.003.240- one detector sniffs for
1 minute,
then phantom for
1 minute
- amp/hr prorated
over 24 hrs
4Fridge
(Dometic
2-way propane)
0.07
(0.32 cooling)
0.284144024.006.816- estimates fridge cools approx. 40 min/hr
 -amp/hr prorated
over 24hrs
5Fridge Vent Fan
(single 50CFM fan)
0.1703005.000.850- only used during
hot weather
6Water Heater
(Suburban propane)
0.750300.500.375- morning/evening
cycles
7Furnace
(Propex propane)
2.1701803.006.510- morning/evening
occasional cycles
8Water Pump5.630100.170.938
9Roof fan
(setting 1)
0.9601803.002.880
10Roof fan
(setting 2)
1.4901202.002.980
11Roof fan
(setting 3)
2.240000- rarely used
12Roof lifts6.03010.020.101
13Bench lift1.16010.020.019
14Light fixture
(single LED
tube retrofit)
0.420601.000.420- Luci lights factor
into all lighting estimations
15Light fixture
(double LED
tube retrofit)
0.910- rarely used
16LED strip
(front cabinet,
dimmer low)
0.030601.000.030
17LED strip
(front cabinet, dimmer high)
0.270
18LED strip
(sink)
0.150300.500.075
19LED strip
(ceiling ambient)
0.220601.000.220
20Exterior light
(incandescent)
0.930- rarely used
21TV
(tv mode)
0.050- no channels,
no data
22TV
(dvd mode)
0.0501.7501202.003.50
23Levels monitor0.13020.030.004
24Fantastic fan
(portable,
setting 1)
1.3301803.003.990
25Fantastic fan
(portable,
setting 2)
1.980
26Fantastic fan
(portable,
setting 3)
2.760
27Tivoli
(radio charging)

28Core draw
(driveway)
0.145144024.003.480- items: 1, 3
- amp/hrs prorated
over 24hrs
29Core draw
(camping)
0.429144024.0011.234- items: 1, 3, 4, 8
- amp/hrs prorated
over 24hrs
Cool day scenario18.644- items: 6, 7, 14,
16, 18, 29
Hot day scenario22.834- items: 5, 6, 9, 10,
14, 16, 18, 24,
25, 29
Conserving day scenario 14.114- items: 9, 29

2016 Trip 8: The Hip...Canada's band

Sharbot Lake PP - Aug 2016

Let's just start by saying that our little blurb about camping this weekend pales in comparison to what happened Saturday evening in Kingston...the end of The Tragically Hip's tour, and the last concert they will ever play.  An emotional tour for both the band and its fans, who were stunned by the announcement  in May that Gord Downie has terminal brain cancer. A poignant end to a 30 year musical journey that over the years created a soundtrack of Canadiana. It was an amazing and emotionally charged evening, the entire country watching, enjoying, and saying thanks for being Canada's band for so many years.

Headed out after work, the traffic is surprisingly light for a summer Friday evening. Made great time to the Park, got registered and then made our way to the site. We were able to reserve what may be the nicest waterfront site in the Park. It is a good size, level, and with lots of privacy. Well tucked in from the road, and although a bit of a challenge with a sharp downward turn from the road, once again, going slow and taking your time proves we can place the Alto pretty much anywhere.




2016 Trip 7: a beach bum vacation

Sandbanks PP - Aug 2016

Friday
Headed down to Sandbanks this morning to start one week of vacation. One of our favourite locations, Sandbanks is apparently the largest freshwater sandbar and dunes in the world!  The hot weather has continued in Ottawa, so we figure Lake Ontario should be nice and warm for swimming.