A growing number of those around here. Kyle (member here = KyleInCowichan IIRC) installs them.
dave
dave
Ok, battery lifespan. Some manufacturers are providing a 10 year warranty, so I'd say that's the absolute minimum lifespan for a well maintained battery in a bank sized appropriately to discharge no more than 20 percent. Solar-One is one brand offering 10 year warranties.
If you look on the Trojan for lifespan charge discharge info, you will see that some of these batteries can be cycled over 5000 times if the depth of discharge is no more than 20 percent. Some products are rated for more some are rated for less. Here's one example.
About sunlight hours - I'm not planning any solar power so sunlight makes no difference. I've got unlimited smoke from my outdoor boiler which could be used to power a generator via gasification (if the smoke is properly filtered).
All the off grid inverters allow you to plug a generator right into them. Then they can directly pass through the generator power instead of draining the batteries. The inverters also have a battery charge controller, so when demand is not high the inverter will charge the batteries from the generator power. The good inverters also have a on/off generator trigger, so if your generator can accept the trigger it's completely automated. Or you can run the generator 24/7/365, the fuel is free. Running like that will require some regular maintenance but that's expected.
If you look at power consumption for central air conditioning, it's about 3500 watts. A fully operating oven/stove is also in that range and a clothes dryer is up there too. A modest 4kw system can power ALL these big ticket items, just not all at once. Off grid requires a bit of planning and common sense and conservation.
So a modest 4kw system requires a power source (take your pick, solar, wind, gasification, fuel powered generator, etc). It requires an inverter, these are about $2000. The inverter has everything you need (battery charge controller, etc) except breakers and wiring. You need a battery bank. That's maybe $2000 - $4000 to power a small household without giving up any luxuries and without having to drain the batteries past 20 percent (assuming a constant power input from a generator).
I'm still in early planning stages but this seems more than doable, it seems like a fantastic investment that will pay for itself quickly and pay out big.
If you are not familiar with generators powered via gasification this is a good primer - https://www.youtube.com/watch?v=a6e3CprVTi8
This system is based on the decades old FEMA plans for emergency power, this system is a lot smaller than I am capable of since I have a lot more wood fuel and smoke generated from my home heating and water heating boiler anyway.
This system is based on the decades old FEMA plans for emergency power, this system is a lot smaller than I am capable of since I have a lot more wood fuel and smoke generated from my home heating and water heating boiler anyway.
Wood gas was big in the Commonwealth during the war years rationing. You can see olden photos of civilian cars with a huge bladder mounted on top or towing it on a big trailer.
a 20% depth of Discharge DoD is a luxury, most designers target 50-60% so you really need to baby the cells to get 10 years. All it takes is one bad cell and then you have to start from scratch.
BTW If you make the investment in storage batts it would be a crime not to have any solar panels. Run the gen set in the winter or on laundry day.
a 20% depth of Discharge DoD is a luxury, most designers target 50-60% so you really need to baby the cells to get 10 years. All it takes is one bad cell and then you have to start from scratch.
BTW If you make the investment in storage batts it would be a crime not to have any solar panels. Run the gen set in the winter or on laundry day.
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Yes, better think of 6 to 8 years. 8 Years only if the batteries are stored in a room that has climate control/airco.
As far as I'm concerned 50 - 60 percent discharge means the whole idea is a non starter. If I can't design it for less than 20 percent discharge I'm not going to bother. Most designers are dealing with intermittent power sources, with a generator I will have no extended down periods and that helps a lot with DoD.
I agree, one bad cell and you have to replace the whole bank. From my perspective, that's not really a problem. The "old" but still functional batteries will be put to use in other non critical applications. Our family business requires a lot of batteries, some of the bigger diesel stuff requires two heavy duty 12 volt batteries in parallel, so I always have a use for extra batteries.
I'm looking into that as a possibility. But if the cost of the panels and the cost of a stand alone charge converter get out of hand this option is out. I'd rather just get a bigger battery bank. (The inverter charge controller is for the generator input only I think, not for solar which requires another charge controller.) Adding solar isn't simple, it's a big cost and a lot of different parts.
Batteries will be in a climate controlled and ventilated storage room in my house with the inverter wall mounted directly above about 12 inches away from the electrical panel (on the other side of the wall).
> Some manufacturers are providing a 10 year warranty
Full pay-off?
When I put a 3-month battry in the plow-truck, and it fails in 24 months, they pay-off the 12 months I didn't get. And generally only apply it to purchase of another battry at the same store, often same-brand.
(As it happens I'm now on month 71 of my 36-month buy, and it seems to take/hold charge, so I'm ahead for now.)
Full pay-off?
When I put a 3-month battry in the plow-truck, and it fails in 24 months, they pay-off the 12 months I didn't get. And generally only apply it to purchase of another battry at the same store, often same-brand.
(As it happens I'm now on month 71 of my 36-month buy, and it seems to take/hold charge, so I'm ahead for now.)
agreed a non-starter, what is the property anyway a summer lake house? Do a proper cost analysis before deciding to cut the cord. IMO it would pay to have an experienced designer review your assumptions. Your proposed system sounds like a high maintenance affair in light that the chief complaint was paying for access to grid electricity even tho the house was empty or low consumption. I think 100 /mo is not near the break even point. I wonder about insurance and local permits with 80% combustion power. I have a feeling the villagers may burn the place down due to noise & pollution if it doesn't blow up by itself.
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The property is my house. I live here 365 days a year and don't often leave for more than 24 hours because I have several daily responsibilities like filling up my wood boiler to heat my house and water. One more responsibility (energy system maintenance) isn't a big deal. My annual electric bills are somewhere around $2500 - $4000, I'd have to check to be more specific. The boiler is already running all day everyday with no complaints, you can't even see the boiler or the smoke from the road. The boiler is over 50 feet from the house to comply with insurance regulations. A generator in an insulated hut very near the boiler wouldn't make enough noise to hear in my own house, let alone at my nearest neighbour's house 1/4 mile down the road. There's nothing that could possibly blow up except the generator. Even if it slips a piston it's not going to cause any damage to anything but itself. All the off grid inverters come with all the safety regulation certifications for home installation. And while I'm sure the insurance company may be very interested in the inverter itself and all the wiring inside the house, I doubt they will care at all about the generator powering the system.
The property you are referring to is not viable for alternative energy. While power is not used for 8 months of the year, when we do use power we use a LOT. For example there's a 15 hp electric motor and a couple of other motors that are maybe 10 hp. It's not often that all 3 are running at the same time but there's no way to power that with any off grid alternative. It's an industrial business property, not a lake house.
I agree my plans should be proofed by a pro. As I said I'm in the early planning stages and a big part of my dealer choice for these products is going to be professional level customer support and advice. I won't need much hand holding after my purchases but in the product selection and system planning phase customer support is very important to me. If anything they are going to advise me to severely oversize the system, they make more money with more sales. They certainly won't advise anything less than I need.
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I haven't read the warranty conditions. But like you I am fairly lucky with vehicle batteries even though they are not deep cycle, they are often fully discharged (dead) and they are subject to all the temperature fluctuations of Canada (freezing cold or boiling hot, not much in between). I'd guess I usually get 6 - 10 years out of my car batteries. I would expect more than that out of a big bank of deep cycle batteries that are carefully maintained and never discharged much.
the Pro-rated warrantee is common with batteries, and that's why I will never buy another Die Hard if they still make them. They all die in the third year.
Walmart has a 3 year free swap, 3 years and one day, you lose, kind of warrantee. Make sure it dies in the third year.....It has to be really dead, depending on the tech that checks it. They have some kind of gizmo that they take as gospel. I think it puts a fast charge on it for about 5 minutes and then load tests it to see what they get back.
My lawn tractor battery got run down before winter two years ago, and it froze solid. It would not hold a charge after thawing it out and recharging it......they gave me a new one free, despite one of the caps being split from the freeze.
My trolling motor battery that kept the computer system, Comcast box, and one light running for 4.5 hours last night is a 114 Ah monster (about 70 pounds) from Walmart with a 2/11 date on it, nearly 6 years old. Does it still have all 114 Ah left in it? I doubt it, but I haven't really tested it. It was still at 12.1 volts when the lights came back on.
The WM battery in my Honda will likely fail this winter if it goes much below zero. Two winters ago it wouldn't start below about -10F, last year it started reluctantly at -2 (the coldest we had). It, unfortunately is about 5 years old.
Some closer photos of the batteries and interconnection wiring. The table, and compare cables with 13mm screw head, and the fuse in the cable of the charger..
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CORRECTION
Fresh electric bill in my hand.
last month -- $133.63 for 703KWh == $0.19/KWh
this month -- $139.07 for 734KWh == $0.19/KWh
This is several cents higher than I remembered.
North coastal Maine USA.
Did I miss Osvaldo posting his electric rates?
Fresh electric bill in my hand.
last month -- $133.63 for 703KWh == $0.19/KWh
this month -- $139.07 for 734KWh == $0.19/KWh
This is several cents higher than I remembered.
North coastal Maine USA.
Did I miss Osvaldo posting his electric rates?
0.10979 per KW-Hr
If you sell power back to the grid, you will be lucky to get 20% of that charge back. The system is set up so they can claim they are "Green" and buy energy, but in reality is going to make money on someone selling power to them.
If you sell power back to the grid, you will be lucky to get 20% of that charge back. The system is set up so they can claim they are "Green" and buy energy, but in reality is going to make money on someone selling power to them.
Particularly, I don't think to sell neither 1mW to the electricity companies. They are a big disaster.
Here in Minnesota:
my monthly electric bill is approx $17.4 + 0.110374 * kW.hr
my gas bill is approx $11.46 + 0.581246 * Therms
Local government here takes taxes on it, so the fixed portion is actually somewhat variable.
my monthly electric bill is approx $17.4 + 0.110374 * kW.hr
my gas bill is approx $11.46 + 0.581246 * Therms
Local government here takes taxes on it, so the fixed portion is actually somewhat variable.
$0.11/KWH! That hurts for us in California. However I just heard that Quebec's rate is closer to $.05/KWH. The difference between $.05 KWH and $.35 KWH would make a big difference in how many aspects of ones life would be addressed.
Despite many recruiting efforts to get me to consider california, I did some calcs and one would have to make at least 3x the money to have similar disposable income. A "median" house in silicon valley area would be $10000/month for mortgage+taxes+insurance. This is roughly 8x what it costs for the same in MN. Energy usage would be similar in summer and less (san jose has roughly 1/3 to 1/4 the heating degree days as central MN) in winter.
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