Michael Qulek

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since Oct 22, 2013
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Recent posts by Michael Qulek

large off-grid system that supplies all the power we can use, at both 120 & 240VAC.
1 week ago
I got around this issue completely by buying lamps with multiple switches, that turn on one, two, three, or four bulbs.  I utilize compact florescents, that I believe can not be dimmed.  So, with two of these lamps in different locations, I can maximize or minimize the light level simply by the number of bulbs that are fully on.

This works especially well for the middle of the night if I need to get up to go to the toilet, but don't want to be exposed to bright light.  The first of the bulbs is a little 7W CFL, whereas the rest are 25W, so the dim light helps enough with navigation that I am not tripping over anything, but doesn't ruin my night vision.
1 month ago

Tyronne Grey wrote:What are the advantages and disadvantages for this? I'm still planning to go solar


I could suggest that you do NOT buy a kit.  Typically what I see is stuff being bundled together that wouldn't get sold if they were all separate.  The single item that has gotten drasticly cheaper recently is large high-voltage residential solar panels.  Typically in my area, I'm seeing 30-37V 250-300W panels going for 75-85$ each.  You get the very best deals with local cash&carry purchases.  Look on local venues like Craigslist or FaceBookMarketplace for the best deals.  

Going with higher system voltage, and higher voltage solar arrays helps reduce very expensive copper costs.  Here's a budget 24V system you can put together yourself that produces enough power for lights, TV, a computer, and running a frig or freezer full-time, 24/7.

Four 250W residential panels 75$ each, 300$ total
40A MPPT charge controller:  Entry-level model is Epever's Tracer 4210AN.  On Ebay for 120$.  Can handle up to 40A up to 100V.  Wire those four residential panels 2S2P to stay safely below the 100V limit.
Four 6V golf-cart batteries wired in series for 24V.  CostCo has a 210Ah golf-cart for 110$ right now.  Four would be 440$.
1500-2000W sine-wave inverter.  Take a look at Samlex, they are UL-listed, not like the cheap imported junk. 650-850$.  Do NOT get a modified wave inverter if you power anything with an electric motor.
10 gauge copper wire for solar panels:  8 gauge wire between the controller and batteries: 4 gauge between the batteries and the inverter.  Look for cut remnents at HomeDepot/Lowes.  You can usually get the lengths you need at 1/2 price.  For wire, fuses, breakers, connectors, ect, throw in another 100$

Call that 1600$ for a system that can keep a frig running 24/7.  Expect a system like this to make between 2kWh and 6kWh anywhere in the continental US between December to June.
1 month ago
My homestead land is right in the middle of free-range cattle ranches.  Most of my neighbors are generational cattle raisers, with me being one of the exceptions.  Raising cattle has it's pluses and minuses.  If you want to look at it from a land-use point of view, it allows lots of food production on land that would be otherwise uncultivatable, ie: too steep/rocky/dry, ect for farming.  In the arid West, it also helps reduce fire danger, because large amounts of dry grass are being removed.

On the negative side, there's environmental damage do to trampling, soil compaction, and damage to natural water sources, where the cattle all crowd in to drink.

We eat meat, and are not about to give up things like beef, but we attempt to limit consumption to reasonable amounts.  We don't grill big steaks, or make large roasts.  We tend to favor stir-fries, with the addition of some beef, or other meats.

The neighbors down the hill from me are Native American, and one idea I thought worth discussing is whether or not importing bison into our area would be something they would be interested in.  Their status as Native Americans might give them greater pull in terms of getting live bison stock, which I assume has a high price premium attached to it.  They would almost certainly want them for hunting, rather than religious activites, so that might not go well with the groups that could potentually supply livestock.
1 month ago

Nancy Reading wrote:
1) To introduce a simple battery back up system that will power "essentials" such as lights and computer for a few hours. We've done this already at our shop which seems to be successful in keeping us able to sell things over the till for a few hours if we lose power there.


This is easy.  A small 12V system will supply this.  Let's say you consume 125W watts of light electricity for about 8 hours in the winter.  That's five highly efficient compact floursceent bulbs.  That's 125W X 8hr = 1000Wh of power.  Say your TV consumes 50W, and you watch 2 hr per day.  Another 100W.  It takes at least 25Wh of power keeping the inverter turned on.  For 8hr, that's another 200Wh.  Total for an on/off 12V system, 1300Wh.  You don't want to drain your batteries less than 50%.  So, you need (1300Wh X 2)/12V = 216Ah battery.  Two 6V golf-cart batteries, such as a Trojan T-105 fit this size.  Let's say you only get 2.0sunhours (sh) of light in the winter.  That might be optimistic?  To get 1300Wh of power with only 2.0sh you should install 1300Wh/2.0sh = 650W of solar panels.  Maybe three 240W grid-tie panels.

Nancy Reading wrote:
2) Introduce a renewable system that will provide some power to direct use when available. At the moment we're actually leaning to a very simple waterwheel generator rather than solar, mainly because we already have bits to do it (other than the smart inverter, which could be that purchased for #1). The disadvantage is that this is unlikely to give us surplus power for water heating in summer. Solar would give us more in summer (we get a good 20 hours of some sort of daylight in June/July) meaning we wouldn't have to run the stove for hot water for baths or pots of tea.


Keep in mind that 20 hours of daylight does NOT mean 20 sunhours.  A sunhour is the amount of sunlight that keeps the panel at FULL POWER.  A 6am the sun may have risen, but the sun might actually be shinning on the back side of your panels if the panels are facing South, and the sun has risen at East-Northeast.  Maybe by 7-8am, the sun has shifted far enough South to actually be shining on the front of the panels, but at almost a right angle, solar output is only 5%.  Let's say that maybe you get 7-8 sunhours of power in summer.  As your system grows, 12V becomes more and more problematic.  Just too many amps flowing through the wires to get substantial power.  Practical limit is maybe 1000-1500W.  After that the current draw could potentially start getting dangerous.  At this point you are better off switching to 24V.  With a 24V system, loads up to able 3kW are easy to manage

Nancy Reading wrote:
3) Introduce further renewables - solar and/or wind. The surplus from this would be dumped into water heating. The aim is to have a system that keeps a days supply in reserve (currently (if I remember correctly) we use about 10kWhr a day).



Solar by far is going to be the easiest to implement.  I personally would start with solar, and once you have a system up and running, then start to experiment with hydro or wind.  I honestly don't have any practical experience with either, but I don't see many success stories with either.  With solar, the success stories are everywhere.

Nancy Reading wrote:
4) if 3) is successful, consider going off grid. It seems crazy, but most of our electricity charge at the moment is standing charge for our connection, we pay slightly more than most in the UK due to our highlands location. If we have sufficient internal redundancy, then this final stage is the only one that would actually give us a quick payback financially.



With what I've got planned out in section two, I'd say you'd be ready to go off-grid.  Your single biggest problem is going to be switching electronics.  Going from 12V to 24V means at least swapping out a new inverter, and buying more batteries.  Maybe it might be more cost-effective in the long run to start out in section 1 at 24V instead of 12?  Most MPPT charge controllers can handle at least 12 and 24V, but the better quality ones can be used for 12V, 24V, 36V, and 48V systems.  An entry level charge controller that can work at either 12V or 24V is Epever's Tracer 4210AN.  It can handle up to 40A at either 12V or 24V.  That means as much as 1000W if you chose 24V.  A somewhat better choice would be their 6420AN, or even their 8420AN controller.  More amps and more volts for future expansion.  24V inverters cost about the same in side by side comparisions with 12V ones, but you would need two more 6V batteries, and maybe two more 240V panels.

So, in the short-term, you'd need to spend more money to buy two more batteries, and two more panels, but in the long run, you'd save money because you can grow the system without having to replace all the electronics.  Over time, you can upgrade to a larger battery size/number, or upgrade the number of panels.  With the 8420 controller you are likely to expand up to 2400W of solar.  I would say that was money well spent.
1 month ago
Hello Cam

Most likely, your battery is already physically damage from being totally drained, so it's continued usability is questionable.  Lead-acid batteries that get totally drained get sulfinated, which over time permanantly reduces battery capacity.

Does your battery have caps for adding water?  If yes, you can check the acid density with a battery hydrometer.  First, fully charge the battery.  If your charger also has a desulfination setting, run that to.  After finishing, pop off the caps and measure the specific gravity of the acid.  A new battery in good shape will have a density of ~1.260 to 1.275.  Density drops the further down the capacity scale you go.  Anything less than 1.100 after full charging is not likely worth saving.

Chronic undercharging is the typical way that most batteries die, so if you want to add solar, you need to add enough.  You determine how much current you need by battery size.  An off-grid battery designed for slow discharge will be rated for Amphours.  Ignore cranking amps or other automotive parameters.  They are not useful for off-grid.

A general rule of thumb is that lead-acid batteries like charging in the range of 1/10th of C to 1/8th of C, with 1/8th being the better choice.  C is the Amphour rating of the battery.  Most 12V batteries for off-grid use have an Amphour rating of the range of 100-120Ah.  Let's say the battery you have right now is 120Ah.  You divide 120Ah/8 to get a charging rate of 15A.  To get at least 15A of current while charging with at least 12.5V you need at least 15A X 12.5V = 187.5W of solar.

Couple of problems though with real-world applications.  First, is that panels are tested in an artificial test chamber with artificial light, at exactly 1000W/square meter, at exactly 77 degree F.  In the real-world, sunlight is more variable, and the panels are hotter than room temperature.  So the power goes down.  I like to de-rate panels to 85% for real-world production.  So, that 187.5W becomes 187.5W/85% = 220W.

Second variable is the electronics you employ to control the panels.  Yes, absolutely, you MUST have a charge controller when connecting solar to the battery, unless you want to stand there all day with a voltmeter, deciding yourself when the panels need to be disconnected.

Older, cheaper PWM controllers only operate by shutting current off.  They let the battery drag the charging voltage down to battery voltage.  So, the typical 100W solar panel that puts out 5A at 20V, will only produce 5A at 12.5V.  So, that 100W panel becomes a 62.5W panel.  That means to get an honest 15A into the battery, you need three of those 100W panels.  Does that make sense?

New MPPT controllers act like a transformer, taking raw high-voltage solar and transforming down to battery-charging voltage.  The extra amps gets transformed into extra charging amps.  MPPT controllers are more expensive, but so are extra panels.  The break-even point seems to be around 200-300W, depending on what kinds of deals you can get.  So, with greater than 300W, MPPT is the cheaper way to go, whereas an application that needs only 100W is better served with the lower-budget PWM controller.  You decide, but I'd go with MPPT.

Here is a controller that might work well for you, Epever's Tracer 2210AN.  Don't spend extra money on 12V automotive panels.  You pay a price premium for 12V products.  You get more bang for your buck with large, high-voltage residential panels.  The kind they use for grid-tie solar.  You first connect your MPPT controller to the battery, and after it boots up on 12V battery power, you connect the solar panel.   The controller knows already that the battery is 12V, so it takes the 30-37V of the residential panel and transforms it down to battery charging voltage.

Let's say you buy a 30V 240W grid-tie panel.  I see them on Craigslist for ~75-80$ right now.  The incoming 30V gets transformed down to 12.5V for charging the battery.  So, what you get is 240W/12.5Vcharging = 19.2A.  With 85% de-rating, you are actually likely to see 19.2A X 85% = 16.2A.  Your battery will be very happy getting charged that rate.  So, with the 2210 controller going for 77$, and a grid-tie panel for 75$, for a total cost of 152$ you get a fully functional charging system.
1 month ago
Here in the US, my own Schneider XW+ 6848 provides split-phase 120/240V AC, which I need to power my submerged well-pump.  120VAC goes to the standard wall outlets.

I also have their smaller Conext SW4024 inverter for the workshop system.  It also provides 120/240VAC, though all of my power tools so far consume only 120V.

Have you come up with an itemized list yet of what it is you need to power.  At my own homestead, with lights, TV, computer, and the refrigerator running 24/7, I find I need ~3.5kWh of power per day.  More if there are construction projects or whatever.

I could suggest that as a starting point.  You'll need to come up with a system that will provide enough power for the winter months, which will be far dimmer than the summer months.  How many gloomy, cloudy days do you get between sunny ones in the winter?  That will be your breaking point.  I could suggest to you two alternatives.  First, design a solar-only system that can provide your needed power over the winter, or Second, a smaller solar array with a generator backup.

I went with the former, because solar panels are now dirt-cheap in the western US.  We have a local seller's venue here called "Craigslist" that I routinely shop for panels.  Typically you get the best deals on high-voltage residential sized panels (grid-tie style).  With a MPPT charge controller, you can wire strings of grid-tie panels together, run the raw high voltage solar electricity back to your home, and let the MPPT controller transform the high-voltage down to battery charging voltage.  The extra voltage gets transformed into extra charging amps.  At my own cabin, I'm running arrays of four 30V panels in series to get 120VDC.  This gets transformed down to 50-something volts to charge my 48V battery bank.

The 6848 inverter then takes the 48V battery power and converts that to US standard 120/240V 60Hz AC.

I'm at 35 degrees North, and I'm finding that in the winter, in the rain, I get about 0.5 sunhours (sh) of power in December.  On sunny days I'll get 3.0sh. I'd suspect you get at bit less if you North of 55 degrees, and you'll need ~6000W of panels to make 3+kWh of power in winter.   Won't know for sure until you actually have the system wired together.  I'd suggest starting at 6000W of solar, but plan on upgrading if your production lags behind what I've experienced.

Alternatively, go with a smaller 48V system with 3000+ Watts of solar, but incorporating a backup generator that charges the batteries in the winter time.  Both my 6848 and 4024 inverters have ACin terminals to accept 240VAC directly from the generator to charge the batteries.  So, no separate charger is needed.  With a 5000-8000W generator, you can start that up on gloomy winter days and top off the batteries that can't be fully charged.
1 month ago
Just looking at the volume of water, I'd express an unexperienced opinion of not very much at all.  I'd be surprised if it could make 100W.

I think you would be far ahead going with solar instead, even in a cloudy area.

In terms of power, you store the electricity made in batteries, either 12V, 24V, or 48V.  Most likely you'll want to go for 48V for powering a full house, though you could get by with 24V.  Please forget about 12V completely unless all you want to power is some lights, and maybe a TV.

Here are some generalities for you to think about....

12V system: lights, computer, TV
24V system: above, and a refrigerator or freezer, power tools
48V system: above and 240VAC items like big air-conditioners, well-pumps, ect.

I've built all three, and have abandoned 12V completely.  What I tell people is to stick with 12V only if your application has wheels.

The very first thing you need to do is make an itemized list of what you want to power, and how many watthours per day you expect to consume.  I would not even bother with a project without starting here first.  Most new people I've interacted with grossly overestimate the power they can make, and grossly underestimate the power they would consume.  I really hate having to help people fix their mistakes.  So, plan first.

What I myself am consuming on a daily basis is in the range of 3.0-3.5kWh of power.  You could also write that as 3000-3500Wh.  That's for what I mentioned above, with the lights on, a couple of hours of TV and computer time, and keeping the refrigerator/freezer running 24/7.  On irrigation days though, when I'm running the 240V well-pump, that number jumps up to 20-25kWh of power.

One thing to comprehend is the concept of the sunhour.  That is the amount of time the sun can power the panels at FULL power.  Typically for my area, that's 3.0sh in winter, and 6.0sh in summer.  In cloudy, rainy weather it drops down to ~0.5sh per day.  Plan for you winter lows, not your summer highs.

So, to get a realistic estimate of what you can make, divide your total consumption per day by your sunhours.  So, if you need 3.0kWh of power in December, and you get 0.5sh of light, that works out 3000Wh/0.5sh of solar panels = 6000W of panels.  You might find it more economical to scale the solar back to 1000-2000W of solar, and charge the batteries with a generator when a winter storm blows through.

Shop on Craigslist, or Facebook MarketPlace to shop for panels locally.  Shipping is the killer.  Don't order panels through the mail.  You will get far better deals with a cash and carry purchase.  Recently I've gotten four 250W residential panels for 160$ total.  I'd suggest starting at 2000W and working up from there with upgrades as finances allow.

You scale the batteries to your expected load, and the length of time they need to supply power.  Let's say you need 3000Wh per day.  You want two days of power before you start a generator.  You don't want to drain the batteries more than 50%.  You have a 48V battery bank.  The math becomes.... (3000Wh X 2 days X 2 fold capacity)/48V = 250Ah battery.  You could wire eight 6V Trojan T-105 batteries in series to get a 250Ah battery bank at 48V.  At 150$ per battery, that's ~ 1200$ for the batteries.

Lastly, you need a charge controller, and an inverter.  The charge controller takes the raw DC from either your solar, or your waterwheel, and transforms the voltage DOWN to what the battery bank wants.  The inverter takes the DC power out of the batteries and converts it into the 120VAC the wall sockets want.  You want to buy a sine-wave inverter if you want to run anything with an electric motor, like the frig, window fans, power tools, ect.  A square-wave or modified sine-wave will fairly quickly burn out anything running a motor.  Good brands are Samlex, Outback, MorningStar, Schneider, and Victron.  The quality inverters start at ~1200$.
2 months ago