Living off the grid at the cottage for the past 6 seasons has been fine and made possible thanks to our propane fridge and stove, as well as the gas water pump used to fill the raised rain barrels with lake water. Gravity then delivered water to the taps and the toilet. It all worked okay, but the water pressure was very low and required some patience. We have also made do without hot water from the taps. Hot water could be possible with a propane water heater but it would only work if we found a way to increase the water pressure significantly. This would require power to run a pressure pump.
This year, we decided to go for it. We would need to run a pressure pump somewhere between the water source of the raised rain barrels and a new hot water heater. To power this new pump, I would need electricity. I could run the pump off a generator, but that would mean going outside to start a noisy exhaust emitting generator every time we wanted hot water, and the need to bring in gas to power the generator. That would defeat the convenience of having hot water simply by turning on the tap. What I needed was a constant standby source of electricity that would power a pressure pump that would be activated whenever we opened the tap.
The solar power source:
I installed a 100 watt solar panel on the roof of the screened porch, which faces south (Tip: apply roof patch with a caulking gun where you screw the mounting brackets through the shingles to prevent leaks in your roof). The cables (AWG 4 that I ordered with the panel) runs from the panel to a 20 amp PWM charge controller (I bought these online with 30 foot cables from S.A.W. Technology online) http://www.sawtechnology.com/
The charge controller's main function is to protect your battery from overcharging if the sun is shining and your panel is producing more energy than it can store. There are two types of charge controllers. PWM (Pulse width modulation) is cheaper than the MPPT (maximum power point tracking) type. Although the MPPT is more efficient in charging your battery generally, my research suggested that the advantage is very limited in a small scale system. So for this basic project for a seasonal cottage, I decided the PWM should work fine.
Two cables, one positive and one negative, run from the solar panel to the charge controller and two more run from the charge controller to the battery.
Deep cycle batteries are required to store the electricity generated by the solar panel. These are marine batteries or golf cart batteries. They look like large car batteries. Deep cycle batteries are designed to be able to withstand having the charge run down before being recharged, unlike regular car batteries, which are recharging every time you start the engine and never get too low.
Ventilation: The battery should not be indoors as they do off gas some potentially dangerous fumes when being charged or used so it should be in a well ventilated area. You can put them indoors but you have to build a box that is properly sealed and vented with a pipe directly outside.
A solar power company representative in Ottawa recommended I buy at least a group 27 or 31 deep cycle marine battery. That number indicates how much power you can draw from the battery without it having to be recharged. You have to remember that if we get a few cloudy days, the battery has to keep up with the demand for power without much recharging. I chose a Motomaster Eliminator group 27 battery from Canadian Tire. It only cost $149.00.
Inverters: These gizmos convert the power from your battery, which is direct current (DC) electricity like that provided by your car, to alternate current (AC) electricity, which is what you have in your home. You can't run AC appliances off a DC power source without an inverter. I thought I would need to obtain an inverter to power a water pump, but I discovered that they make DC pumps. This means I could connect the pressure pump directly to the battery without using an inverter. An added benefit is that a DC pump uses a lot less power than an alternate current (AC) pump, optimizing the battery power.
http://www.canadiantire.ca/en/pdp/group-27-starting-and-deep-cycle-battery-0102799p.html#.VYseMGfbL5o
The pressure pump:
From the battery, I ran one positive and one negative (black)10 gauge wire purchased at Home Depot to the pressure pump. The pump's manual says to use 10 gauge if the distance is more than 20 feet and less than 50. If it is less than 20 feet, you can use 12 gauge. The positive wire is connected to a Littelfuse and a 12 volt on/off switch before on its way to being connected to the pump, as recommended in the pumps owner's manual. I found the Littelfuse in the automotive section of Canadian Tire and the 12 volt on off switch in the marine section of Canadian Tire. For the pump, I chose a Flojet 04406-143A. http://www.amazon.ca/Flojet-04406-143A-Multi-Fixture-Water-Pump/dp/B0000AXDOY/ref=sr_1_2?s=automotive&ie=UTF8&qid=1435181142&sr=1-2
You can buy it on Amazon, but I bought it from the Pumphouse in Ottawa, and I paid about $50.00 more. It is nice to be able to call them with post sales questions, but I think I would have figured out the answers on my own. For example, I didn't know where I could buy a lintel fuse and 12 volt on-off switch - Canadian Tire is the answer. The switch is in the marine section.
While I'm not a expert on estimating wattage consumption and amps times volts etc... I was advised that this DC pump could easily be powered by a 100 watt panel and a single 12 volt battery. And that indeed proved to be the case.
The Hot Water Tank:
After much research and deliberation I decided to go with a conventional water tank as opposed to the on demand variety. Many modest priced on- demand units had very mixed reviews online. Also, I understand it can be trickier to drain them for the winter which is an important consideration for a seasonal property. I heard of one cottager who thought he had drained it but evidently hadn't done so properly and a part broke. It took several months to get the part so he went an entire season without hot water.
I know there are energy savings to be had with on-demand heaters, but the number of days a year that we have the tank turned is so small that the difference in propane consumption and associated cost wouldn't amount to very much anyway.
One challenge I face was that most propane hot water tanks have to be vented straight up and cannot have an elbow in the vent.
I wanted to install the tank in the basement of the cottage - I built a basement in part so that all the mechanical business could be neatly tucked away and not take up space on the main floor. To vent it straight up would have meant major work to build in a chimney box from the basement through the cottage and through the roof, and significant labour costs to do it. Also it would take up precious space in the cottage. One alternative would have been to build a small shed beside the cottage and have the plumbing run in and out of it for hot water but this would mean more holes running water in and out of the cottage and an outbuilding that would require construction and maintenance. The solution: you can pay for a more expensive model that can be vented through the sidewall using an elbow in the vent pipe. I figured the cost of building a chimney or an outbuilding would probably have offset the savings of avoiding the more expensive model in any event. So we have a Bradfordwhite 40 gallon (the smallest you can get with sidewall venting)
http://www.bradfordwhite.com/sites/default/files/product_literature/103-B_ICON.pdf
The propane model comes in at $1,300.00. It doesn't require electricity to start or operate, which was another key consideration.
Plumbing connections
The plumbing in the cottage is half inch PEX pipes. To tie in the new pressure pump and hot water heater, I would need to add about ten fittings (Tees and elbows) and about 10 to 15 feet of pipe. The first option was to use the Sharkbite fittings available at Home Depot. With these, you just shove the pipe into and it and it locks in place. No need for special tools or soldering. http://www.sharkbite.com/ . The other option was to buy the special crimping tool to install the much cheaper standard PEX fittings.
I saw the crimping tool was on sale at Canadian Tire for $20 off the usual price of $80.00 and given the number of fittings I would have to install, it was economical to buy the tool for this project. You also have to buy the rings that you crimp the pipe over the fittings with.
I also installed a fitting with a shut off valve on the cold water line leading to the hot water tank.
For the connections to the hot water tank, Sharkbite makes steel flexible 18 inch hoses with female connections that screw onto the tank's in and out fittings. The other end of these hoses have the Sharkbite feature that allows you to shove the end of the PEX pipe you want to connect to into the fitting. My hot water tank installer recommended I have steel hose for the first foot or so to and from the tank.
The system is up and running and on Friday, June 20th, 2015, I took my first hot shower at the cottage. It's a really nice addition to the cottage and will make longer stays much more enjoyable. Below is where the picture of me taking the first shower at the cottage was to be posted. Fortunately for readers, the camera steadfastly refused to participate.
Ah, but it can'\t be that easy! After just a couple of weeks, the pump started acting strange. It would kick on and off intermittently when we weren't using water. We checked for leaks throughout the plumbing system but couldn't detect any. I was advised to check inside the pump for debris that could be causing the valve to stay open, even just a tiny bit. I did that and rinsed out one or to tiny particles. I was also advised to install a strainer and a check valve on the intake line. The strainer is just a washer with a steel mesh across the opening. I installed it in the garden hose on the intake side. The check valve is just a small part that I connected in the intake line where the garden hose met the Pex pipe that leads to the pump in the basement. This seemed to fix the problem for the time being.
UPDATE September 2016: After two seasons, I am pleased to report the system is running very smoothly. I stored the battery in my basement, plugging it into a trickle charger, over the winter. It's important not to let the battery charge get too low and sit for an extended period, As I wouldn't be clearing the snow off the solar panel in the winter, I wasn't sure if the battery would be able to continue charging all winter. So I just brought it home. And we haven't had any problems with the pressure pump starting intermittently since I installed the check valve. It's great to not have to boil water every time we want some hot. And having strong water pressure, whether hot or cold, if also appreciated.
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