Emergency backup generator?
Andrea — January 21, 2012
Update: We didn't get the upgraded panel. Thanks for everyone's advice!
Ted and I need some advice in a hurry: The electrician is about to install our electrical panel, and we need to decide whether to pay an extra $2,350 for a panel that's compatible with a backup generator.
We have no immediate plans to install a backup generator, and we hope the grid stays reliable enough that we wouldn't need one. But if we do want a generator one day, it would be a lot cheaper if our panel is ready for it.
Note that our house is run entirely on electricity. No wood stove, no gas range. Our water comes from a well, which requires a pump, and our sewer hookup requires a pump as well.
The idea of burning propane to power our house gives me the willies, but if there's an extended power failure I'd rather burn propane than abandon ship altogether.
Thoughts?
[I should add that the solar panels won't work in the event of a power failure. There's an automatic shutoff if the grid supply goes down, in order to protect line-workers.]
Random Bits
Before installing solar panels, get a home energy audit to find out where you're wasting the most energy. Your house will be more comfortable if you seal leaks and add more insulation, so don't just slap solar panels on the roof without curbing energy use.
Re: Emergency backup generator?
Anonymous — February 8, 2012If you get time check out this link:
http://www.youtube.com/watch?v=GbtRxcb-cmA
Interlock vs Transfer Switch Uploaded by panchohughes
An interlock is around $100, outside 30A generator inlet about $50
Add about $100 for some 10/3 wire and breaker
Hope this helps
Dao
Re: Emergency backup generator?
Electrician — September 24, 2012you are talking about manual (portable) generators here...not automatic (standby) generators
Re: Emergency backup generator?
Danny — May 15, 2012Thanks for link to this video, its been really useful to me.
I also like the way you are documenting your Passive house progress here. Nice one.
Re: Emergency backup generator?
Larry — January 31, 2012We opted out of the upgraded panel, we have an all electric house as well. But we did include an underground conduit to run a wire to our outdoor meter pole away from the house where we might install a generator in the future. I'd rather fire up the generator as needed rather than have a fancy automatic cut-over whole house backup. Keep up the good work, you're making good time on the house. It's great to watch your progress.
Re: Emergency backup generator?
Andrew — January 29, 2012Many of the commercial buildings I work on have emergency backup, but always for a limited selection of critical systems wired to once or more specific panels. Once the genset kicks in, the building has to be disconnected from the grid for safety, so your electrician must surely be able to do the same trick with PV? Might be worth a conversation.
Had a quick look at homed depot and for $2,800 you get the transfer switch, 12 circuit panel AND 10kw backup generator....
http://www.homedepot.com/Electrical-Alternative-Energy-Solutions-Generat...
Andrew
Re: Emergency backup generator?
Melissa — January 24, 2012I would agree with Terry's suggestion above. I lost power at my house in Connecticut for 9 days during the Halloween storm this past year and I would have loved to have a generator. A lot of people I spoke with had the plug-in generator set-up that Terry describes, at least to run their well pump and refrigerator, and possibly their boiler depending on the size of the generator. That seemed to work out fine for them.
At the same time, I would consider the contribution of a whole-house generator to the re-sale value of your home, since it seems like something people are looking for more and more, particularly in the northeast. I know I am considering that as an option as well.
I'd like to add that this is a great blog and as someone who is hoping to build a "passive house" someday, it is great to hear the process.
Re: Emergency backup generator?
Jerome Lisuzzo — January 22, 2012Hi Andrea - I'm currently working with a local architect to build a new Passive House residence for me and my wife here in Kennett Square, PA. We have the land, and we're currently working on finalizing the design details for the house, which will be a relatively modest 28'x38' two-story footprint (a strict rectangle). I've been reading everything the net has to offer on passive houses, and your blog has been very helpful and inspiring. In my estimation, you've done an incredible job with both the house and the blog! But on to the primary reason for this reply...
After several prolonged power outages in our current home, this fall I finally decided that we needed a generator. After a lot of thought, research, and discussion (much of it with my nephew, who is a master electrician in Michigan), I purchased a portable 6800 watt Rigid generator from Home Depot (which ran just under $1000). I then hired an electrician to install a Reliance Protran 10 circuit transfer panel (http://www.reliancecontrols.com/ProductDetail.aspx?30310A). He also charged me just under $1000 (parts and labor). We had him hook up the 10 most important circuits to the panel (some appliances, like the water heater and the well pump, took up two circuits each), and the installation included a 25 foot cord that he hard-wired in our garage. The installation only took him a couple of hours.
Now, if we have a power outage, I can plug the generator in (keeping it outside of the garage, of course), and simply throw the switch for whichever circuits we want to use. With 6800 watts, we can't use them all at once. But, for instance, we can turn on the well pump and charge up the expansion tank. Then we can turn on the (electric) water heater and heat the water for a while, or we can turn on the TV, internet, and refrigerator.
Any time we turn on one of the 10 circuits, the panel automatically shuts off that circuit from the electric company's incoming supply line to prevent any issues. The system is, in my opinion, requires only a bit more thought than a fully automated system, but I consider it pretty much idiot proof. At worst, if you run too many of the 10 circuits at one time (and draw too many amps), it will pop the breaker on the generator. But the big potential problem (of having the generator and the electric company "connect" is automatically prevented by the panel. Our generator can handle up to 30 amps at one time.
So the bottom line is we feel we're now adequately protected, and it cost us about $2000 for the generator, panel, and installation. Hope that helps!
Re: Emergency backup generator?
Terry D Davenport — January 22, 2012Hellow to you guys.
I think I would save the money on the extra electrical costs. I use a Honda 3500 generator and I have some extra plug ins to go directly from the generator to my refrigerator and also the well pump. I have to unplung the appliance and re plug it into the generator. This keeps it simple and also safe. I would take the saved money and invest it in more energy saving things for your beautiful home. Like insulating curtains could save lots of energy. I assume you have a heat recovery ventilator in your home. I would construct a drying closet for your laundry and hang the wet clothes up and then run the heat recovery ventilator to dry your clothes. The exhaust on the drying closet would make the room go slightly negitive on air pressure so no moisture would be driven into the walls. My dryer uses so much energy that I zeroed out my cottage by hanging up my clothes in the main house and running my HRV. Some ideas for you guys. Just keep it simple.
Re: Emergency backup generator?
Curtis Jackson — January 22, 2012We have a couple of Xantrex portable battery packs we keep plugged in and charged at all times. We figure one can run fridge + standalone freezer, and the other we can use to power our CPAP machines so we can safely sleep at night without power, and charge laptops/phones/etc during the day.
This doesn't keep you warm, but I'm guessing in your house that is less of an issue.
These battery packs can also be used to jump-start a car (I've done it), and they can be recharged from a car's battery.
If the likelihood of the grid going down is remote, I think this is a much cheaper solution. I'll bet one of these battery packs has enough juice to power a mattress pad heater. Did I mention that mattress pad heaters are awesome? We can keep the house very chilly because the bed itself is warm.
Re: Emergency backup generator?
Ed D. — January 22, 2012I'm guessing that that $2,350 must be for automatic switching of the whole house electrics to a generator. Anything else has got to be a lot cheaper, hasn't it?
What some people do is have a separate "AC essentials" circuit (fridge, CH pump, well pump, that sort of thing) which is on a plug. In the case of a power cut they manually unplug it from the mains and plug into the output of a generator (or off-grid type PV inverter). You lose heavy current non-essentials in a power cut (kitchen particularly) but the house stays safe and basically habitable. You can always plug a kettle or slow cooker or something directly in to the generator.
Perhaps the way to go would be to have two smaller panels with a plug between. One for the heavy stuff you lose, one for the lighter stuff you'd want to run from the generator. Sounds a lot cheaper than $2,350.
Re: Emergency backup generator?
Donald B. — January 21, 2012"[I should add that the solar panels won't work in the event of a power failure. There's an automatic shutoff if the grid supply goes down, in order to protect line-workers.]"
I certainly agree about the auto disconnect from grid, but shouldn't there be a way to run your PV system separately after disconnecting it from the grid? It might have to be a manual system and that manual system might (probably will?) require a manual reconnect when power returns, but it would sure beat:
1) Paying an extra $2,350 PLUS the cost of a generator (and fuel)
2) Having 4.76 kW of PV goodness go to waste during a power outage!
3) The $$$ of an upgrade to the PV system that would allow it to automatically take over and disconnect from the grid without creating a risk for line-workers.
Could the backup generator compatible panel be wired to the PV giving a super combo option1 and 3 combined?
Re: Emergency backup generator?
Andrea — January 21, 2012Actually that's 3.96 kW of PV goodness (the page you got the number from was out of date). But yes, I sure wish we could tap into those.
There is no way to run the PV system off the grid. From what I understand, we'd either need a less-efficient hybrid inverter with some kind of battery backup, or we'd have to go dangerously off-label with a MacGyver-esque workaround (and details on such a workaround are scant). Otherwise I'd have no objection to a daytime-only PV backup.
If battery prices plummet and hybrid inverter efficiency improves, we could just swap out the inverter and use the batteries in case of emergency. A tempting scenario -- I'd certainly like to save the $2,350 now and avoid the prospect of a propane tank on our property.
Re: Emergency backup generator?
dad — January 21, 2012Ours (cost $4200 installed - 8kw) came with the switching panel. We had to provide a concrete base and the line for propane. Total, $5000.
Re: Emergency backup generator?
Andrea — January 21, 2012Thanks for the details — Ted and I were wondering about that.