C. West wrote:I was wondering if anyone is running some normal appliances on nothing but solar. By normal I mean fridge, freezer, dishwasher, computer. Is it even possible with current solar and battery tech to run a "normal" house?
Cristo Balete wrote:C. West, "normal" depends on where you are. Solar is about location, location, location. There are a lot of threads here to look at, we've discussed this a lot. If you mean completely off grid, there's a lot to know beyond whether it's sunny or not.
Solar equipment is expensive, and it needs to be maintained. Deep cycle batteries are very expensive, and if you know what you are doing you might....might make the best ones, the most expensive ones last 8-10 years, then they have to be bought again, all at once, because one battery that isn't new will drag the others down to its level, that's a tragic waste of money. 10 years ago we spent $2500 on 8 batteries for a small system. We just replaced the same batteries for $3500. So that's $1,000 more than we paid the first time. It's an expense that won't be the same, and it's quite high for a repetitive household expense.
At some point everyone using battery power, including electric vehicles, will find out that nobody actually recycles batteries. Batteries have a few of the internal parts that can be recycled, but there are only a few places that do that, and it takes freight to get them there, which is expensive. The last time I looked there was only one company in Germany that dealt with the other, more toxic components of a dead battery, and shipping it there by dirty, diesel-spewing fuel doesn't seem very green, and I don't think other countries do that. Maybe this will change when the world has a lot more batteries to recycle, but as of now, when we hand off 8, 10, 12 old batteries, or large electric vehicle batteries for recycling, odds are the worst parts of them are just dumped somewhere very unfortunate.
It's very important to understand DC and AC electricity, the difference, and what to do when things go wrong. Birds cling to wires with their feet and damage the wire coating, or rodents eat wires coming from the panels if the wires aren't in something protective. If the panels are on your roof, you have to go up there and clean them, wash off pollen, leaves, pine needles, tip them at different seasonal times into the sun as it lowers and raises off the horizon. I prefer to have them on the ground, but they have to be in the sun for a minimum of 6-8 hours a day, no trees, no building shade during those hours at any time of year.
Knowing the difference between a 12 volt, 24 volt, 48 volt system is important. If it's just installed and they walk away, you will need to know how many circuits you have, how many appliances can be on at one time, and what to do if the alarm goes off on the inverter. We have yet to find an electric company that wants to work on a solar system that has a problem. We just had a really good inverter break down, and there's no one to fix it. I really, really don't want it to go into a landfill somewhere, so I'll probably end up shipping it, expensively, somewhere, if I can find a place.
It's very important to know the wattages of all appliances and how much they will use on a daily basis, including all of the high-wattage appliances like a vacuum, coffeemaker, dishwashers use heaters to dry, printers running for any length of time, hot water pots. An electrical hot water heater did not work for us in our situation, it just took the batteries down too much when it had been overcast. We had to have a backup system for hot water, and what's the point of two hot water systems? An electric dryer runs on 220 volts, instead of the regular 125 volts, and that's huge for a solar system with a special 220V circuit. I wouldn't even attempt it.
Most appliances these days look like they are off, or turn themselves off, but there is something called phantom power, they are taking trickles out of the system to be up and running sooner when you push a button. This is not good for a solar setup. Trickling power out of batteries when there's been overcast is just using up very expensive batteries. All of our appliances are on power strips and everything is off overnight, except the refrigerator. They also act as breakers and protection.
Companies that sell the panels want to tell you about your yearly solar number of hours, and that that somehow fits on a chart for what works. We live day by day in the real world. In the winter there are fewer hours that can have sun on panels, yet it's the time of year when we need more power, lights are on sooner, we cook more inside and for holidays. So the kinds of solar totals they try to sell you on may be questionable, unless you live in San Diego where it rains something like 3 days a year and is sunny the rest.
Two shed expenses... there has to be a shed for the batteries separate from a shed that has the controlling equipment in it because the batteries off-gas hydrogen and sulfur dioxide, which can eat the wires inside very expensive electrical components. The batteries need distilled water once every 1 month to 6 weeks, and should be added in a dry location, not with rain blowing into them, or snow or dust, blowing sand....a real shed you can stand up in to work on them, and several gallons of distilled water on hand. You'll need of storage space for corrosion spray, broom, paint brush for dusting them off, a funnel for the water, paper/pen to keep track on, manuals, tooth brush to clean off corrosion....
Cristo Balete wrote:The saltwater batteries are pretty new, and apparently the company is going bankrupt. From their website....
"Thanks for reaching out to Aquion Energy. As a former customer of the company we are sure that you read in the press release dated July 21, 2017 that Aquion has “emerged” from Chapter 11 restructuring and bankruptcy. We have prepared this short FAQ in hopes of providing a clearer picture to our former customers.
"When can I buy Aquion batteries again?
"Rebuilding after a chapter 11 filing can be difficult and time consuming. There will be a period of time needed in order to regroup, rehire, and requalify the manufacturing process, supply chain, and sales pipeline. There are also improvements to chemistry and form factor of the battery which will take time and effort. All of these efforts will result in a better product for a future market."
Cristo, if you stick to the name brand manufacturers of equipment there should be no compatibility problems with nicad or NiFe batteries or lithium for that matter. The problem comes when the cheaper equipment is used without the programmable set points for absorb, float and low voltage disconnect...
Cristo Balete wrote:Sue, thanks for the info on the Nickel-Iron batteries.
The saltwater batteries, I'm glad they are working for you.
The only thing about storing batteries in a garage is if they are near a sparking type of device, like a gas heater with electronic ignition. the hydrogen gas (from lead-acid and Nickel-Iron batteries) is dangerous. It can cause an explosion. I can't imagine hydrogen gas does much good to a car paintjob.
Apparently there's some issue with compatibility with home solar equipment and nickel-iron batteries, as mentioned below.
Disadvantages of Nickel Iron Batteries
22 November 2017
By Mario Santini
Nickel-Iron (Ni-Fe) batteries, also known as Nickel-Alkaline or Edison batteries are rechargeable batteries with a long life expectancy, high Depth of Discharge (DoD) and a reputation for durability. The battery can withstand overcharge, overdischarge and short-circuiting and yet last 20 years or more.
The disadvantages however outweigh the advantages.
The initial cost is at least 30% over a high-end Lead Acid battery of comparable size (considering usable energy) and also still a lot dearer than Lithium-ion batteries.
Nickel-Iron batteries have lower energy density and lower specific power compared to lead-acid batteries (or in layman's terms are less efficient). The cells take a charge slowly, and give it up slowly (cannot supply sudden large power spikes). This means one would need more batteries and more solar panels to achieve the output of a 'standard' lead-acid based power system. In addition, Ni-Fe batteries have a significant self-discharge rate of 1% per day.
They produce a lot of hydrogen, daily gassing is required to get the expected performance. Hydrogen gas is explosive, therefore good ventilation is imperative.
The characteristics of Ni-Fe batteries are not supported by most solar equipment. The voltage window is so wide that standard inverters are likely to shut themselves down well before the battery is fully discharged. Hence claims like "100% usable capacity" are exaggerated which will further add to cost, size and maintenance.
While not as bad as Ni-Cd batteries, RPC strongly advises against Nickel Iron batteries for home solar systems. The initial cost is unlikely to pay off unless maintenance is conducted meticulously - for decades. If you need high quality deep cycle batteries, take a look at these Lead Acid or Lithium-ion batteries.
Stacy, what kind of ags system are you using? I.e. what triggers the generators? There is a lot of tricks that can be used to lower genny time. The Aquions have unconventional set points and the standard ags settings would not cut it you would have to tweak them a bit...
Stacy Witscher wrote:I also have aquion batteries, and have a stack of replacement batteries as well. My main issue right now is finding someone able to help me with the battery systems should a need arise. The solar people that I had come inspect the system and walk me through some things have no experience with these batteries. My bigger issue is the backup generators, how to keep the main one from coming on so often. I don't like the amount of diesel that we use on that generator or the amount of propane that we use on the property in general, but given how difficult things have been lately, I don't want to harp on people's habits. It's been a painful, difficult thing, I don't want to make things worse.
Sorry to hear about your loss... First off usually if its a xantrex inverter the AGS controls work through that. What model? green and white rectangle? the older SW? I know one of the problems we face in the solar industry is its growth rate. As it grows so fast the real "money" is in install. Tweaking and upgrading is finicky and time consuming. Then if you" fix" something on an older system and an equally old component fails you all of a sudden "own" the problem. It is so common the former company I consulted for stopped doing upgrades and concentrates only on full systems now. I like to tinker so its a good niche for me. If I were you I would carefully read over your Aquions manual especially about the absorb time required. Usually absorb time on the xantrex AGS has a default amount of hours that is set up for Lead acid. Lead acid requires several hours of absorb to get from say 75 percent to 90 percent"full" The Aquions do not. So right there a good solar company wanting you to get max life out of their gear sets up the generator to give maximum life to the batteries and damn the fuel usage... for lead acid, Aquions are new, not lots of experience out there so it would be easy to miss. Lots of savings there. Next comes the trigger points for the AGS. Dive in and see at what voltage it is set to turn on the generator and how long it waits to see if that voltage holds or bounces back. Aquions can take 80 percent discharge according to their literature with no problem but their max amperage draw is fairly low so something big comes on, the voltage drops fast, the Older Xantrex AGS triggers too soon and you have a wasted generator cycle. Once an AGS is triggered it runs through a full cycle it does not care if it triggered 2 minutes before the sun came out. Outback controllers are invisible to xantrex inverters and vice versa so a generator turning on 2 minutes before the solar array powers up is common since the AGS and the charge controller do not talk. The trick there is to program in a "quiet time" window in the AGS that matches the sunny parts of the day... AGS' are dumb and are a last resort failsafe that cannot match the smart human in the loop...
Stacy Witscher wrote:The off-grid solar people that I have talked to just don't have any interest in dealing with my battery system, I'm not sure that I could convince them otherwise. And they are considered by many as the best off-grid solar people in southern Oregon. I need some time to gain enough knowledge to deal with things myself.
I was looking into what was triggering the generator, but then my grandbaby died, and life has been in standstill since. Some think it is a problem between the outback charge controllers and the xantrex inverters, but I don't know.