New guy from NYC with a few questions and TIA's:)

downtown NYC
downtown NYC Registered Users Posts: 11
Hello and thank you for your help. Went through Sandy last year and realized I was in a bad situation... I have since been messing around with solar panels 4 100 watt renogy loaded on my 19th floor terrace. In the summer I do ok, but in the winter- IE presently, not so good. Realizing this, I have two sets of battery banks- grown over time and paranoia of course: 1150 ah's battery bank number one and 900 ah battery bank number two. I figure 7 days worth of emergency lighting, 12 volt tele, cell phone, etc.

I face NW. I am heavily reliant upon secondary or reflective light off of the many buildings surrounding me such as the world trade center for example. I recently purchased a 50 watt vertical wind turbine with hopes of hiding that on the terrace as well.

So here are the questions I have:

1. How should I be measuring what I have coming in? It seems very low to me. Using a renogy 40amp mppt CC, I see 12-20 volt, 0.2 amps and perhaps one amp hour for the day. I understand my lack of direct sunlight is the cause, but perhaps ideas such as using mirrors such as in this isolated situation?

2. In order to bump up the power in. I was thinking of either creating a 48 volt solar array in or a 24 volt series/ parralel array in. This would then feed my 12 volt battery bank(s). Does this make sense?

2a. I was thinking of experimenting with 95 watts worth of Freight Harbors amorphous solar panels. I am thinking experimentation because of my lack of sun situation. I have read that although less efficient, these panels actually work much better in low light conditions.

3. Can anyone recommend so tried and true 12 volt light bulbs that I can wire into a lamp thus to maintain the illusion of normalcy. My kids lost it last time the lights went out.

To the future, thanks in advance,

Andrew

Comments

  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New guy from NYC with a few questions and TIA's:)

    Welcome to the forum Andrew.

    I think your throwing away money trying to get solar or wind to work in your location.

    Solar panels aren't very efficient to begin with, but yours aren't even pointed directly at the sun which will greatly decrease their output. Before you could have enough PV to recharge those huge battery banks you will run out of terrace space.

    For example: 400 Watts of PV on an MPPT controller and a 12 Volt system should be capable of 25 Amps of current. You are seeing about 1/10 that. This is definitely due to the lack of direct sun.

    Can you use mirrors? Mirrors don't reflect 100%, and the angle would have to change repeatedly throughout the day in order to keep the sun pointed to the panels. An expensive experiment without much hope for success, I'm afraid.

    50 Watt vertical wind turbine: even under the best of circumstances these are not efficient. The vertical design even worse than horizontal because half the energy is lost turning the blades back into the wind. Out on the terrace ... is there really a 20 mph steady breeze through there? It would be very unpleasant living space if there were, and you won't realize much power if there isn't.

    In short, you can't harvest power that isn't there and for you there's no power to harvest.

    So let's look at the problem differently: you want back-up power for outages. A generator is usually the best bet, but that's probably out of the question on the 19th floor (gasoline and such).

    You have 1150 Amp hours (12 Volt?) and 900 Amp hours (12 Volt?) of battery. If these are 12 Volt banks you'd be better off reconfiguring them to higher Voltage, lower current. Improves efficiency and makes current handling easier. The first bank would be 6.9 kW hours of stored power which is massive really. It would also require 115 Amps of charge current or about 1800 Watts of PVin direct sun to recharge. See the problem? Chances are your batteries are already sulphated from insufficient charging.

    Reduce the power need would be the first step. Figure out the minimum amount of power you need on hand to see you through the emergencies (length and frequency come into play). Batteries are going to die over time whether they are used or not, even if charged properly. Keeping a large bank viable "just in case" is money down the tubes if the outages don't justify the investment.

    So let's say you've worked out how much power you need. Size the battery bank accordingly. Example: need 2 kW hours per day for 4 days = 8 kW hours stored energy. That's 334 Amp hours @ 48 Volts. Notice the change in Voltage: charging now requires 34 Amps, which is easier to deal with than 115. A nice inverter-charger will keep them up when you have grid and supply AC when you don't.

    AGM batteries are more resistant to self-discharge so will last "in storage" longer. But they are more expensive and harder to check.

    That's a start on it.
  • downtown NYC
    downtown NYC Registered Users Posts: 11
    Re: New guy from NYC with a few questions and TIA's:)
    Welcome to the forum Andrew.

    I think your throwing away money trying to get solar or wind to work in your location.

    My hopes are to learn here. I plan on moving to a more solar friendly location in the next few years.

    Solar panels aren't very efficient to begin with, but yours aren't even pointed directly at the sun which will greatly decrease their output. Before you could have enough PV to recharge those huge battery banks you will run out of terrace space.

    For example: 400 Watts of PV on an MPPT controller and a 12 Volt system should be capable of 25 Amps of current. You are seeing about 1/10 that. This is definitely due to the lack of direct sun.

    Can you use mirrors? Mirrors don't reflect 100%, and the angle would have to change repeatedly throughout the day in order to keep the sun pointed to the panels. An expensive experiment without much hope for success, I'm afraid.

    50 Watt vertical wind turbine: even under the best of circumstances these are not efficient. The vertical design even worse than horizontal because half the energy is lost turning the blades back into the wind. Out on the terrace ... is there really a 20 mph steady breeze through there? It would be very unpleasant living space if there were, and you won't realize much power if there isn't.

    In short, you can't harvest power that isn't there and for you there's no power to harvest.

    OUCH. I no I no pipe dream...

    So let's look at the problem differently: you want back-up power for outages. A generator is usually the best bet, but that's probably out of the question on the 19th floor (gasoline and such).

    I have a Yamaha 2000. I am looking into converting this to a propane system with a 20 gallon tank. I feel a lot safer with that sitting on a terrace.

    You have 1150 Amp hours (12 Volt?) and 900 Amp hours (12 Volt?) of battery. If these are 12 Volt banks you'd be better off reconfiguring them to higher Voltage, lower current. Improves efficiency and makes current handling easier. The first bank would be 6.9 kW hours of stored power which is massive really. It would also require 115 Amps of charge current or about 1800 Watts of PVin direct sun to recharge. See the problem?

    So your suggesting that I convert my battery banks over to 48 volts as well as the panels?


    Chances are your batteries are already sulphated from insufficient charging.

    I was looking at the BLS battery saver to combat this issue. One for each bank.



    Reduce the power need would be the first step. Figure out the minimum amount of power you need on hand to see you through the emergencies (length and frequency come into play). Batteries are going to die over time whether they are used or not, even if charged properly. Keeping a large bank viable "just in case" is money down the tubes if the outages don't justify the investment.

    Investment already made...

    So let's say you've worked out how much power you need. Size the battery bank accordingly. Example: need 2 kW hours per day for 4 days = 8 kW hours stored energy. That's 334 Amp hours @ 48 Volts. Notice the change in Voltage: charging now requires 34 Amps, which is easier to deal with than 115. A nice inverter-charger will keep them up when you have grid and supply AC when you don't.

    Which inverter-charger would you recommend? Can you recommend a site that explains this a little better. I'm ignorate:)

    AGM batteries are more resistant to self-discharge so will last "in storage" longer. But they are more expensive and harder to check.

    That's a start on it.

    Thanks for your time
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New guy from NYC with a few questions and TIA's:)

    If you're going to move that will change everything. Back-up power or solar, what's right for one location won't necessarily be right for another. This stuff is highly site-specific.

    A propane powered Yamaha is probably the best solution for outages where you are. No worse than having a BBQ on the terrace and those inverter-generators are very quiet.

    If you need a lot of stored energy, it is better to use a higher Voltage battery bank. Some further explanation here: http://forum.solar-electric.com/showthread.php?15989-Battery-System-Voltages-and-equivalent-power

    As the battery bank goes so goes the array: you need about 70 Vmp to recharge a 48 Volt system. Even if you can't get full charge rate from your array you may get some power that will extend the run time. The worst problem is that the longer the batteries are at <75% SOC the faster the sulphation sets in, reducing their capacity and lifespan.

    There are several inverter-chargers that may work for you. Exactly which one depends on the number of features you need, such as whether or not 240 VAC is required and what the total Wattage load at any time would be. None of them are cheap: expect to pay near $2,000 for one. Sometimes you can find used ones on a good deal. And of course if you up the battery bank to 48 Volts the inverter will need to be at that Voltage as well.

    One other thing I will mention although it may not apply since you have a pending change of location: LiFePo batteries could be a good back-up power choice for someone in an apartment. They are much more expensive, but take up less space and are resistant to problems of low SOC (no sulphation) as well as having slightly higher stored power capacity. They are somewhat more finicky to manage in terms of charging/discharging and you really have to study a lot to understand how to use them properly (and get the right ones to begin with). For most off-grid installs they are not worth it, but an apartment may make the advantages worth the extra cost and hassle.
  • downtown NYC
    downtown NYC Registered Users Posts: 11
    Re: New guy from NYC with a few questions and TIA's:)

    So for the time being, you suggest-say a magnum, 48 volt charger/ inverter. It will allow a 120volt plug via wall outlet to keep the batteries topped off in the good times and provide 120 volt ac usage as well in the bad times from the batteries. My concern with just leaving the batteries hooked up to a charger is this: in the past I originally did this with a schumocker charger. I began to hear off gassing in a sealed AGM. No good. Will this problem continue?

    Andrew
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New guy from NYC with a few questions and TIA's:)
    So for the time being, you suggest-say a magnum, 48 volt charger/ inverter. It will allow a 120volt plug via wall outlet to keep the batteries topped off in the good times and provide 120 volt ac usage as well in the bad times from the batteries. My concern with just leaving the batteries hooked up to a charger is this: in the past I originally did this with a schumocker charger. I began to hear off gassing in a sealed AGM. No good. Will this problem continue?

    Andrew

    Well the Schumacher was probably not a 3-stage charger and did not have settings for Absorb Voltage suitable for AGM's or some combination thereof. The chargers built in to units like the Magnum or Outback are programmable. AGM's require lower Absorb Voltage than flooded cells do, and you don't want to hear any gas escaping from an AGM!

    So with the right settings (varies with the particular battery) the I-C will take the batteries through Bulk, Absorb, and then hold them in Float as long as AC power is available. About once a month you want to disconnect the grid power and run the batteries down 25% or so then recharge them again. This will make sure everything is working for when the power goes out and you have no choice; you don't want to find the batteries have died while plugged in.
  • KenZ71
    KenZ71 Solar Expert Posts: 58 ✭✭
    Re: New guy from NYC with a few questions and TIA's:)

    Gotta ask what are you planning to power in an outage? Are you looking to provide heating, cooking & lighting?

    All those could be accomplished with a camp stove & lantern.

    Sandy was labeled a once in a hundred years storm so most likely that won't happen again. Although it is good to be prepared. How about prep for getting out of the city. Get a decent size frame pack, sleeping bag, foam pad and a small white gas stove. In a pinch you can burn kerosene in those too. This way if Sandy's evil sister comes to town again you can load your pack and catch the next outbound train. Go about 2 to 3 hours and you will find a relatively affordable hotel to hangout for a few days.

    A few of my neighbors took off to Disney when Sandy hit, also an option. Might be about the same cost as batteries & solar panels.
  • downtown NYC
    downtown NYC Registered Users Posts: 11
    Re: New guy from NYC with a few questions and TIA's:)

    Not preparing for the end of times. I am trying to slowly build a system here and learn so that I can just adapt it to when I move. Not so much a prepper. Truth is above 42nd Street. the city was powered.

    Andrew
  • downtown NYC
    downtown NYC Registered Users Posts: 11
    Re: New guy from NYC with a few questions and TIA's:)

    The Schumacher stated it was a three stage charger with AGM settings. A POS never the less. So to sum up here. Panels and batteries wired in a 48 volt configuration. A magnum or Outback inverter/ charger wired to the wall outlet and batteries. Run the batteries down once a month and recharge. So now this leads to a 5500 dollar investment with say a flex charge power center. Can I hook up the inverter with a charge controller from the 4 panels without the 5500 dollar expense and instead just the 2000 dollar investment inverter/ charger?

    Andrew
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: New guy from NYC with a few questions and TIA's:)
    The Schumacher stated it was a three stage charger with AGM settings. A POS never the less. So to sum up here. Panels and batteries wired in a 48 volt configuration. A magnum or Outback inverter/ charger wired to the wall outlet and batteries. Run the batteries down once a month and recharge. So now this leads to a 5500 dollar investment with say a flex charge power center. Can I hook up the inverter with a charge controller from the 4 panels without the 5500 dollar expense and instead just the 2000 dollar investment inverter/ charger?

    What you need minimally is the inverter-charger and its programming interface, the battery bank, the wires, and over-current protection for the DC and AC connections.

    PV & charge controller are optional. Code-compliant installation may require other things (all wire in conduit, accessible disconnect, etc) depending on local application. No real need for the Flexcharge power center.
    Also What I don't understand is this. Since this is for emergency situations, wouldn't I do better leaving the batteries in a 12 volt configuration- since we are now in essence removing the poor solar output and are now replacing it with a guaranteed charger thus having more reserve amp hours in a 12 volt configuration?

    Andrew

    No.
    12 Volt systems are inherently less efficient than 24 or 48 Volts. More of the power (Watts) is Amps when less of the power is Volts, and more Amps means more heat; power lost. Higher Voltage systems can use smaller wiring for the same power because of this (you need larger wire to handle greater Amps).

    Whether you configure batteries as 12 Volts or 48 Volts the stored power remains the same:
    12 Volts; Eight 6 Volt 220 Amp hour GC2's as four parallel strings of two in series = 880 Amp hours * 12 Volts = 5280 Watt hours.
    24 Volts; Eight 6 Volt 220 Amp hour GC2's as two parallel strings of four in series = 440 Amp hours * 24 Volts = 5280 Watt hours.
    48 Volts; Eight 6 Volt 220 Amp hour GC2's as one string of eight in series = 220 Amp hours * 48 Volts = 5280 Watt hours.
    (All at 50% DOD.)
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: New guy from NYC with a few questions and TIA's:)

    I would be surprised if your building would allow a genset or a BBQ on a balcony.

    And I would be very afraid of getting CO (carbon monoxide) into your neighbors' (and your) units. If it was not "illegal" in my building, I would work to make it illegal.

    Between CO and fire issues (propane tanks get hot and vent, liquid fuel spills) and lack of ability to fight a fire ~200+ feet up a building during a power failure... I would not do it.

    Did the building have emergency power after the storm (elevators, local water pressure, etc.)? Can't imagine 19 flights of stairs are much fun after a few days of outages (carrying food+water+waste, etc.).

    If the building is a condo--Perhaps wiring up for low power LED lighting, reviewing amount of stored fuel on hand, ability to manage flooding (much of building support is in basement--did it flood/at risk of flood?) all are big issues.

    If you where going to "camp" in the unit. Then you can look at very small/efficient DC lighting. Even small flashlights that can last for days to weeks at low power output on a pair of CR123 or AA batteries would be a big help (just keep a brick of batteries for use in lights, small radio, etc.).

    http://www.foursevens.com/products/flashlights/Pro (2x AA flashlight and 2x CR123A flashlight)

    https://www.foursevens.com/manuals/Manual_Quark%20Pro%20Series_20120323.pdf

    "low" is enough to walk around and read something (very bright moon light)... The high is pretty much like a hand held spot light with 1-2 hours of run time.

    For cooking--The "solution" for marine use was alcohol. Common, clean burning fuel (still recommend a battery powered CO and Smoke detectors) fuel, that also can be put out with plain water (gasoline, kerosene, etc. all float on water).

    Today--A large apartment building/condo is not a great shelter in place if there is loss of power/water.

    Ideally, you want to find a place that you can shelter in place for 3 days minimum. I try for 2 weeks at my home minimum.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: New guy from NYC with a few questions and TIA's:)

    Even if you have power for cell phones and computers--Many times, there are hand full of hours to a couple of days maximum of backup power for cell/internet enabled equipment (assuming the network points have survived).

    For AC power, you will only want to run very efficient equipment. Is that 300 Watts or less for laptop, cell, a few LED lights? Or are you looking to run the refigerator for X days (~1,200 - 1,500 watt minimum AC inverter and a relatively large battery bank). You may be able to reasonably have three days of backup power--But beyond that, then what (no sun for solar power, cannot run genset, etc.).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • downtown NYC
    downtown NYC Registered Users Posts: 11
    Re: New guy from NYC with a few questions and TIA's:)
    BB. wrote: »
    I would be surprised if your building would allow a genset or a BBQ on a balcony.

    Doesn't allow, but were talking emergency.

    And I would be very afraid of getting CO (carbon monoxide) into your neighbors' (and your) units. If it was not "illegal" in my building, I would work to make it illegal.

    CO would be ventilated outside???

    Between CO and fire issues (propane tanks get hot and vent, liquid fuel spills) and lack of ability to fight a fire ~200+ feet up a building during a power failure... I would not do it.

    Did the building have emergency power after the storm (elevators, local water pressure, etc.)? Can't imagine 19 flights of stairs are much fun after a few days of outages (carrying food+water+waste, etc.).

    NONE WHATSOEVER. It was very bad particularly for the seniors. It felt like Katrina. No foresight. No help

    If the building is a condo--Perhaps wiring up for low power LED lighting, reviewing amount of stored fuel on hand, ability to manage flooding (much of building support is in basement--did it flood/at risk of flood?) all are big issues.

    If you where going to "camp" in the unit. Then you can look at very small/efficient DC lighting. Even small flashlights that can last for days to weeks at low power output on a pair of CR123 or AA batteries would be a big help (just keep a brick of batteries for use in lights, small radio, etc.).

    Naw need creature comforts. Real lighting. Small tv. Etc

    http://www.foursevens.com/products/flashlights/Pro (2x AA flashlight and 2x CR123A flashlight)

    https://www.foursevens.com/manuals/Manual_Quark%20Pro%20Series_20120323.pdf

    "low" is enough to walk around and read something (very bright moon light)... The high is pretty much like a hand held spot light with 1-2 hours of run time.

    For cooking--The "solution" for marine use was alcohol. Common, clean burning fuel (still recommend a battery powered CO and Smoke detectors) fuel, that also can be put out with plain water (gasoline, kerosene, etc. all float on water).

    Today--A large apartment building/condo is not a great shelter in place if there is loss of power/water.

    Ideally, you want to find a place that you can shelter in place for 3 days minimum. I try for 2 weeks at my home minimum.

    -Bill

    Thanks,

    Andrew
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: New guy from NYC with a few questions and TIA's:)

    Problem with CO is you don't know where it is going (or even if it is being generated without testing/monitoring the equipment).

    You vent it outside your unit, the exhaust rises or blows against the building, and into a nearby unit (who also has their windows open because they need ventilation too).

    If you where running a smokey/diesel genset, they would notice and say something. You run a quiet/clean burning genset, they may not notice the problem until it is too late. People are poisoned by Genset CO emissions quite often. It is hard to justify the risks.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • downtown NYC
    downtown NYC Registered Users Posts: 11
    Re: New guy from NYC with a few questions and TIA's:)
    BB. wrote: »
    Problem with CO is you don't know where it is going (or even if it is being generated without testing/monitoring the equipment).

    You vent it outside your unit, the exhaust rises or blows against the building, and into a nearby unit (who also has their windows open because they need ventilation too).

    If you where running a smokey/diesel genset, they would notice and say something. You run a quiet/clean burning genset, they may not notice the problem until it is too late. People are poisoned by Genset CO emissions quite often. It is hard to justify the risks.

    -Bill

    Got ya. Thank you. I just purchased a Magnum 4448PSE charger/ inverter. Amped:)