Introduction!

[Mark Ross]

Hi All,

My wife and I will be building a small (1024sq.ft.) ranch-style bungalow just outside Merrickville, ON. We are going to go for an off-grid setup instead of having hydro run to the lot. We will get an external propane tank for gas supply.

Right now in the process of getting building permit and the inspector has told me to get the permit, I need specs for the furnace and hrv that I would be installing.

I was wondering if anyone had any specific recommendations for lower power / more electrically efficient units? So far considering the Venmar EKO for the HRV but not sure about the furnace, if there are recommended unit, etc

Any and all advice appreciated!

Thanks,
mark

[Rob Beckers]

Hi Mark,

Taking this from an off-grid job we're in the process of installing; we have nothing to do with the furnace/HRV, but I did look at them to make sure they are reasonably efficient (and they were), and to take their load into account for the system sizing calculations. Ultimately they need to be sized properly for your house though, in terms of heat output and air-exchanges. This is what the house has:

The Furnace is a Continental C96.
http://continentalheatingandcooling.com/products/9600-series/
The nice part about this furnace (for off-grid use) is that it comes with an ECM blower motor; those are DC, variable speed, motors, and an air-flow sensor runs it as-needed to get the desired air flow, as opposed to always running flat-out.

The HRV is a Lifebreath 195 ECM.
http://www.lifebreath.com/line.php?line_id=8 (scroll down for the "195 ECM" version)
Again, this has an ECM motor, running at the speed needed instead of flat-out. DC motors are also a bit more efficient vs. AC motors.

Despite the efficiency of the appliances, these are very large loads when it comes to off-grid! That furnace blower motor is the largest load in the house in winter, bar none, by a wide margin! You may want to give some thought to a pellet or wood stove, with the propane furnace relegated to 'backup'.

The HRV is no small load either, and we plan to put that on a timer, and run it 10 minutes every hour (to start with, if humidity becomes a problem we'll increase that). Running it 24x7 would put a very large strain on the system, or require a larger system, and it's expensive enough as it is.

If you are going to do the install yourself, please keep us in mind for supplies. We have good prices for off-grid supplies (and help you size things, with install advise etc.).

-RoB-

[Mark Ross]

Hi Rob,

Thanks a lot for your prompt and informative response! We are looking to have a 24,000btu Napolean fireplace (no electrical requirements) in our living room. I am not sure how well this will work in the darkest days of a "near-Ottawa" winter (if you know what I mean). Even if we had to bring a generator online to bulk up the batteries during the worst of furnace use/winter I don't think this is the end of the world.

We will be at least well insulated with double-stud 12" exterior walls and a ton of insulation!

That is interesting info about the HRV - prob a good idea on my side as well to just run on a timer in the same fashion, and find the right balance.

I am hoping to do as much of the installation as I can! I like your price list and your Canadian Solar 300W panels are looking pretty attractive!

At this point I am considering about 8KW of panel on a 48VDC bank @ 800 or 1200Ah. I favour Surrette batteries since they are made in Canada.

I see most of the inverters you list are for grid-tie - do you deal with off-grid inverters as well?

Thanks,
mark

[Rob Beckers]

Mark, almost everything on the price list is grid-tie, simply because that is what we stock at this time. I've been selling lots of off-grid supplies as well though, despite the lack of advertising we acquired a bit of a reputation for this, even a number of other installers are buying off-grid items from us.

Once we have the new warehouse/office up and running I will start stocking off-grid items as well. There just isn't enough space right now.

For panels the best deal at this time are the Chinese-made CSI 250W panels for 78 ct/W. Same quality and warranty as the Ontario-made ones. We just received 25kW of them, with some already spoken for. They will be available again, but because it's a container-at-a-time coming in at CSI there will be a number of weeks between allocations.

We can supply Surrettes as well; it's the brand I most often use and sell to others (usually their mid-line such as the S-530 and such).

For the large off-grid we're working on now we are installing 8kW of panels and 24x Surrette S-1725 to make a 48V battery bank. Sounds much like what you have in mind. It's designed to produce an honest 300 kWh per month, using seasonably adjustable racking from FabRack, even in the dark of winter.

Feel free to contact me by E-mail to discuss further.

-RoB-

[Mark Ross]

For panels the best deal at this time are the Chinese-made CSI 250W panels for 78 ct/W. Same quality and warranty as the Ontario-made ones. We just received 25kW of them, with some already spoken for. They will be available again, but because it's a container-at-a-time coming in at CSI there will be a number of weeks between allocations.

There are some places I choose to save, this would not be one of them. I would prefer to spend on Ontario made panels, even if it's not the absolute best deal...the prices are edging under a dollar a watt so I can live with that.

For the large off-grid we're working on now we are installing 8kW of panels and 24x Surrette S-1725 to make a 48V battery bank. Sounds much like what you have in mind. It's designed to produce an honest 300 kWh per month, using seasonably adjustable racking from FabRack, even in the dark of winter.

This sounds like what we want, pretty much! Love it!

I'll contact you via email to discuss some pricing and so forth!