Personal Finance

MicroFIT solar plan: is there any way to also use it as Battery Backup?

  • Last Updated:
  • Sep 16th, 2014 9:30 pm
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Deal Fanatic
Jun 11, 2005
7238 posts
1632 upvotes
Mississauga
dani_toronto wrote:
Jan 17th, 2014 1:48 pm
Hmm... how to combine incoming Hydro with battery power? I assume sparks would fly (in a bad way) if those 2 touch each other.
Should I have some house circuits off-grid, fed exclusively by the batteries? Or are there controllers that can somehow use as much battery power as possible, and get from the grid the rest that the house may need?
This is not my expertise but i found this site should answer all your questions.

http://www.wsetech.com/battery.php
Deal Guru
User avatar
Nov 18, 2005
10812 posts
2155 upvotes
Kingston
dani_toronto wrote:
Jan 17th, 2014 1:48 pm
Hmm... how to combine incoming Hydro with battery power? I assume sparks would fly (in a bad way) if those 2 touch each other.
Should I have some house circuits off-grid, fed exclusively by the batteries? Or are there controllers that can somehow use as much battery power as possible, and get from the grid the rest that the house may need?
The microFIT sponsored part of your system provides power to grid and you get paid the microFIT rate ($0.396 currently) for 100% of this power. Conceptually you don't use any of this power. You use "regular" power that you purchase from your hydro provider at the regular rate.

If you had a separate system that powered batteries this would minimize your hydro costs. My hydro panel is set up so that part of it can be switched to generator powered in the case of a power outage. I expect it could be set up to have that part of the panel powered by batteries instead.

FYI for a 10kw microFIT system you are looking at about $30K. Battery fed systems are more expensive.

If you are looking for something to cover power outages a standby generator would be a WAY better way to go than solar and batteries.
[OP]
Sr. Member
Jul 10, 2005
754 posts
121 upvotes
Toronto
JWL wrote:
Jan 18th, 2014 9:40 am
The microFIT sponsored part of your system provides power to grid and you get paid the microFIT rate ($0.396 currently) for 100% of this power. Conceptually you don't use any of this power. You use "regular" power that you purchase from your hydro provider at the regular rate.

If you had a separate system that powered batteries this would minimize your hydro costs. My hydro panel is set up so that part of it can be switched to generator powered in the case of a power outage. I expect it could be set up to have that part of the panel powered by batteries instead.

FYI for a 10kw microFIT system you are looking at about $30K. Battery fed systems are more expensive.

If you are looking for something to cover power outages a standby generator would be a WAY better way to go than solar and batteries.
Yes, looking at the numbers, even if I was using batteries, it would be better to sell my solar to the grid and re-buy it to charge my batteries from the grid. The downside is that if the outage is long, Id' have no way to keep recharging the batteries.

The current status of this technology (and its economics and rules) makes for some silly situations. I'd feel so stupid if I was powerless during an outage with a roof full of panels. Having to burn fossil fuel for backup power doesn't make me feel too 'green' either.

Thanks for your input.
Deal Guru
User avatar
Nov 18, 2005
10812 posts
2155 upvotes
Kingston
dani_toronto wrote:
Jan 18th, 2014 1:33 pm
Yes, looking at the numbers, even if I was using batteries, it would be better to sell my solar to the grid and re-buy it to charge my batteries from the grid. The downside is that if the outage is long, Id' have no way to keep recharging the batteries.
Even if you could get it set up to be able to switch over your panel generation to charge your batteries you'd have issues with effectiveness in the winter which is the time you would want the battery backup the most (for heat). Winter is the worst time for solar power generation between short days, low angle, snow/ice on the panels and seems to be more cloud cover.
Deal Addict
Jul 4, 2004
4594 posts
756 upvotes
Ottawa
The first and biggest problem with what you are proposing is that it's against micro-Fit rules. Their rules are very specific that you need to be connected directly to the grid and cannot have battery backup (otherwise you could just recharge your batteries from another source and sell that power back into the grid).

If you want a backup system, you'll have to do as others have suggested and get a second solar system separate from the micro-Fit one but as others have suggested, it would be WAY cheaper, easier to simply have a generator for backup power.
Deal Addict
Feb 24, 2007
1371 posts
55 upvotes
JWL wrote:
Jan 18th, 2014 9:40 am
The microFIT sponsored part of your system provides power to grid and you get paid the microFIT rate ($0.396 currently) for 100% of this power. Conceptually you don't use any of this power. You use "regular" power that you purchase from your hydro provider at the regular rate.

If you had a separate system that powered batteries this would minimize your hydro costs. My hydro panel is set up so that part of it can be switched to generator powered in the case of a power outage. I expect it could be set up to have that part of the panel powered by batteries instead.

FYI for a 10kw microFIT system you are looking at about $30K. Battery fed systems are more expensive.

If you are looking for something to cover power outages a standby generator would be a WAY better way to go than solar and batteries.
Have you ever calculated the cost differences between the two, solar as a backup source vs. a standby generator, especially for a generator that may never be used, you have that large upfront cost. I know solar is more expensive, but at least you can use it everyday in addition to charging batteries. Assuming a generator only gets used once or twice in its life, would it have been better to go solar?
Newbie
User avatar
Apr 5, 2010
93 posts
31 upvotes
Waterdown
I do know you can combine Net-metering with Microfit. With Net-Metering, the AC generated by the Panels goes directly into your main Service panel. Excess electricity not used by your house would then cause the Load meter to spin in reverse and you can build up credits. And depending on the type of Inverter, it should work during a power outage. Not sure if you have to disconnect from the grid, by flipping a switch, in that situation or not. Also since there are no batteries, you'd be without any generation at night.

There are already installers selling combo systems, especially in rural areas. You earn the full micro fit income on one side, and reduce or almost wipeout your Hydro bill on the other.
Another plus, is the cost is cheaper having both done at the same time, as there is allot of duplication in the install.
[OP]
Sr. Member
Jul 10, 2005
754 posts
121 upvotes
Toronto
dominik wrote:
Jan 21st, 2014 8:42 pm
I do know you can combine Net-metering with Microfit. With Net-Metering, the AC generated by the Panels goes directly into your main Service panel. Excess electricity not used by your house would then cause the Load meter to spin in reverse and you can build up credits. And depending on the type of Inverter, it should work during a power outage. Not sure if you have to disconnect from the grid, by flipping a switch, in that situation or not. Also since there are no batteries, you'd be without any generation at night.

There are already installers selling combo systems, especially in rural areas. You earn the full micro fit income on one side, and reduce or almost wipeout your Hydro bill on the other.
Another plus, is the cost is cheaper having both done at the same time, as there is allot of duplication in the install.
That sounds closer to my original idea. Do you know if Microfit directly forbids backup batteries? With net metering I could use the feed that goes to my service panel to do whatever I want... including charging batteries.

Will keep researching. Thanks
Member
User avatar
Feb 21, 2009
214 posts
East Coast
michelb wrote:
Jan 20th, 2014 7:00 am
The first and biggest problem with what you are proposing is that it's against micro-Fit rules. Their rules are very specific that you need to be connected directly to the grid and cannot have battery backup (otherwise you could just recharge your batteries from another source and sell that power back into the grid).
Very true, I've researched this & was told same thing over phone. Good info!

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